Notice of Pre-AIA or AIA Status
The present application, filed on or after March 16, 2013, is being examined under the first inventor to file provisions of the AIA .
Allowable Subject Matter
The combination of both dependent claim 17 and 18 into claim 1 and 12 and 20 would be allowable over the prior art of record.
Response to the Applicant’s arguments
The previous rejection is withdrawn. Applicant’s amendments are entered. Applicant’s remarks are also entered into the record. A new search was made necessitated by the applicant’s amendments.
A new reference was found. A new rejection is made herein.
Applicant’s arguments are now moot in view of the new rejection of the claims.
Claims 1, 12 and 20 are amended to recite and the primary reference is silent but HUANENG teaches “...determining, by the power control unit, whether a stuck-or-obstructed-propeller
condition is present by determining whether the rotational speed of the electric
motor is at or below a first threshold selected to correspond to a rotational speed
indicative of the propeller being stuck or obstructed and the torque value is at or
above a second threshold indicative of an abnormal torque load; and
in response to determining that the stuck-or-obstructed-propeller condition is
present directing, by the power
control unit, the inverter to not supply the power to the electric motor”. (see abstract where the turbine is detected as being stuck and about to crash and the motor output is overloaded and the maximum is reached and then a warning signal is provided that the pitch motor is running very high and then a maximum allowable overload torque is reached and then a fault is detected to stop the turbine from moving for repair; A device for preventing propeller jamming of a wind turbine based on a preventive alarm, comprising:
The monitoring module is used to monitor whether the output torque of the pitch motor of the wind turbine is overloaded;
The judgment module is used to monitor the output torque overload of the pitch motor, and further judge the output torque overload of the pitch motor;
If the output torque overload of the pitch motor returns to normal before reaching the maximum allowable overload torque, the pitch system is running normally;
If the output torque overload of the pitch motor reaches the maximum allowable overload torque, and the duration of reaching the maximum allowable overload torque reaches the first threshold, the wind turbine will send an early warning signal to perform maintenance work on the wind turbine or continue to observe the operation of the pitch motor. If the maintenance operation of the wind turbine is completed, the pitch system will operate normally; if the duration of reaching the maximum allowable overload torque reaches the second threshold from the first threshold, the wind turbine will send a fault signal and stop, and the wind turbine will be registered. Machine maintenance, after the maintenance is completed, reset and restart operation.)
It would have been obvious for one of ordinary skill in the art to combine the teachings of HUANENG with the disclosure of CALVERT with a reasonable expectation of success since HUANENG teaches that a wind turbine can be detected as being past the maximum allowable torque. Then an alarm can be provided for maintenance based on the status of the pitch motor and when it goes past that level the turbine is stopped and reset to prevent it from jamming and crashing. This provides an observation improvement and better maintenance of the turbine. See abstract.
Claim Rejections - 35 USC § 103
In the event the determination of the status of the application as subject to AIA 35 U.S.C. 102 and 103 (or as subject to pre-AIA 35 U.S.C. 102 and 103) is incorrect, any correction of the statutory basis (i.e., changing from AIA to pre-AIA ) for the rejection will not be considered a new ground of rejection if the prior art relied upon, and the rationale supporting the rejection, would be the same under either status.
The following is a quotation of 35 U.S.C. 103 which forms the basis for all obviousness rejections set forth in this Office action:
A patent for a claimed invention may not be obtained, notwithstanding that the claimed invention is not identically disclosed as set forth in section 102, if the differences between the claimed invention and the prior art are such that the claimed invention as a whole would have been obvious before the effective filing date of the claimed invention to a person having ordinary skill in the art to which the claimed invention pertains. Patentability shall not be negated by the manner in which the invention was made.
The factual inquiries for establishing a background for determining obviousness under 35 U.S.C. 103 are summarized as follows:
1. Determining the scope and contents of the prior art.
2. Ascertaining the differences between the prior art and the claims at issue.
3. Resolving the level of ordinary skill in the pertinent art.
4. Considering objective evidence present in the application indicating obviousness or nonobviousness.
This application currently names joint inventors. In considering patentability of the claims the examiner presumes that the subject matter of the various claims was commonly owned as of the effective filing date of the claimed invention(s) absent any evidence to the contrary. Applicant is advised of the obligation under 37 CFR 1.56 to point out the inventor and effective filing dates of each claim that was not commonly owned as of the effective filing date of the later invention in order for the examiner to consider the applicability of 35 U.S.C. 102(b)(2)(C) for any potential 35 U.S.C. 102(a)(2) prior art against the later invention.
Claims 1-5 and 12-16 and 20 are rejected under 35 U.S.C sec. 103 as being unpatentable as obvious in view of Untied States Patent Application Pub. No.: US20120094555A1 to Calverly et al. that was filed in 2009 and in view of United States Patent Application Pub. No.: US20170373502A1 to Gjerpe filed in 2015 and in view of Japanese Patent Pub. No.: JP2009194993A to Mitsushirma that was filed in 2008 and in view of Chinese Patent Pub. No.: CN114899799A to Huaneng filed in 2022.
In regard to claim 1 and 12 and 20, Calverly discloses “1. A method of implementing a torque fuse in an electric marine propulsion system with a torque fuse, the method comprising: directing, by a power control unit (see paragraph 62-65 where the mechanical drive line includes an engine and a rotor and an all electric mode with a torque fuse)
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Calverly is silent but Gjerpe teaches “....an inverter to supply power to an electric motor of an electric marine propulsion system for a watercraft; (see claim 1 where the vessel has a first inverter and a second inverter and in a second mode the first and the second inverter provides power from the first DC bus to the first ac bus and the second inverter provides power from the second DC bus to the second AC bus)
It would have been obvious for one of ordinary skill in the art to combine the teachings of GJERPE with the disclosure of CALVERT with a reasonable expectation of success since GJERPE teaches that the ship can include a first DC bus and a first AC bus and a first inverter between the DC and AC bus and a second inverter that can be coupled between the DC and AC second bus and the device can include selectively connected and disconnecting the inverters. These can provide thrusting at a high or low voltage connection for a more efficient load sharing and responding to a short circuit current. See paragraph 1-7 and claims 1-8.
Mitsuhima teaches “...receiving, by the power control unit, sensor data indicating a rotational speed of the electric motor;
receiving from the inverter, by the power control unit, a torque value for the electric motor; (see element 9 where the speed detector can provide a rotational speed of the propulsion induction motor in the abstract)
determining, by the power control unit, whether the rotational speed of the electric motor is at or below a first threshold and the torque value is at or above a second threshold; (see claims 1-3 where the speed command signal can provide a torque limiting value as a function of the speed command signal and a torque command signal is compared with a torque limit value so it does not exceed the limit value)
and in response to....,” (see abstract that recites Inverters 4 and 5 are connected to an inboard bus 8 via circuit breakers 6 and 7, respectively. The speed detector 9 outputs the rotational speed detection signal ωr of the propulsion induction motor 1 from the pulse signal output from the pulse generator 3. The speed controller 10 calculates and amplifies an error obtained by subtracting the rotational speed detection signal ωr from the rotational speed command signal ωr * from the speed setter 11 and outputs a torque command signal τe * to the inverters 4 and 5. Current detectors 12 and 13 detect the three-phase output current values iu, iv and iw of inverters 4 and 5, respectively, and output them to inverters 4 and 5, respectively. The torque limit value setter 14 gives a torque limit value command below the rated torque to the inverters 4 and 5, and the inverters 4 and 5 operate so as to limit the torque below the torque limit value command.)
It would have been obvious for one of ordinary skill in the art to combine the teachings of MITSUHIMA with the disclosure of CALVERT with a reasonable expectation of success since MITSUSHIMA teaches that the ship can include a torque limiting device so the electric device cannot move past a torque limiting value. The device has a vector control of the inverter and motor based on the speed command. See claims 1-3 and paragraph 1-10.
Calverly is silent but Gjerpe teaches “.... directing, by the power control unit, the inverter to not supply the power to the electric motor”. (see claims 1-13 and paragraph 47-48 where the first inverter can be selectively disconnected and the second inverter can be connected where in paragraph 22 a rotational speed of the thruster may be adjusted by adjusting the frequency of the AC power stream output by the respective consumer inverter. )
It would have been obvious for one of ordinary skill in the art to combine the teachings of GJERPE with the disclosure of CALVERT with a reasonable expectation of success since GJERPE teaches that the ship can include a first DC bus and a first AC bus and a first inverter between the DC and AC bus and a second inverter that can be coupled between the DC and AC second bus and the device can include selectively connected and disconnecting the inverters. These can provide thrusting at a high or low voltage connection for a more efficient load sharing and responding to a short circuit current. See paragraph 1-7 and claims 1-8.
Claim 1 is amended to recite and the primary reference is silent but HUANENG teaches “...determining, by the power control unit, whether a stuck-or-obstructed-propeller
condition is present by determining whether the rotational speed of the electric
motor is at or below a first threshold selected to correspond to a rotational speed
indicative of the propeller being stuck or obstructed and the torque value is at or
above a second threshold indicative of an abnormal torque load; and
in response to determining that the stuck-or-obstructed-propeller condition is
present directing, by the power
control unit, the inverter to not supply the power to the electric motor”. (see abstract where the turbine is detected as being stuck and about to crash and the motor output is overloaded and the maximum is reached and then a warning signal is provided that the pitch motor is running very high and then a maximum allowable overload torque is reached and then a fault is detected to stop the turbine from moving for repair; A device for preventing propeller jamming of a wind turbine based on a preventive alarm, comprising:
The monitoring module is used to monitor whether the output torque of the pitch motor of the wind turbine is overloaded;
The judgment module is used to monitor the output torque overload of the pitch motor, and further judge the output torque overload of the pitch motor;
If the output torque overload of the pitch motor returns to normal before reaching the maximum allowable overload torque, the pitch system is running normally;
If the output torque overload of the pitch motor reaches the maximum allowable overload torque, and the duration of reaching the maximum allowable overload torque reaches the first threshold, the wind turbine will send an early warning signal to perform maintenance work on the wind turbine or continue to observe the operation of the pitch motor. If the maintenance operation of the wind turbine is completed, the pitch system will operate normally; if the duration of reaching the maximum allowable overload torque reaches the second threshold from the first threshold, the wind turbine will send a fault signal and stop, and the wind turbine will be registered. Machine maintenance, after the maintenance is completed, reset and restart operation.)
It would have been obvious for one of ordinary skill in the art to combine the teachings of HUANENG with the disclosure of CALVERT with a reasonable expectation of success since HUANENG teaches that a wind turbine can be detected as being past the maximum allowable torque. Then an alarm can be provided for maintenance based on the status of the pitch motor and when it goes past that level the turbine is stopped and reset to prevent it from jamming and crashing. This provides an observation improvement and better maintenance of the turbine. See abstract.
In regard to claim 2 and 13, Mitsuhima teaches “.. 2. The method of claim 1 further comprising: receiving from a user interface, by the power control unit, a new value for the first threshold; and storing as the first threshold, by the power control unit, the new value” . (see FIG. 7 where the torque limiting value is provided as an input based on the rated power consumption; FIG. 7 is a diagram illustrating an example of the characteristics of the torque limiter 42, where the horizontal axis represents the torque command τe * that is the input of the torque limiter, and the vertical axis is the internal torque reference τe * ′ that is the output of the torque limiter. .
The torque of the induction motor 1 for propulsion shown in FIG. 4 can be controlled in proportion to the magnetic flux command Φ2 ′ * and the internal torque reference τe * ′ by the action of the vector control described above. However, in order to control the torque at high speed. In general, a method is used in which Φ2 ′ * is constant and the motor torque is controlled by the internal torque reference τe * ′.
On the other hand, most of the power supplied to the inverters 4 and 5 is consumed by the propulsion induction motor 1. If the efficiency of the propulsion induction motor 1 and the inverters 4 and 5 is ignored, the power consumed by the electric propulsion device is P = ωr × τ (3)
It becomes. Here, P represents power consumption [W], ωr represents the rotational speed [rad / s] of the propulsion motor 1, and τ represents the generated torque [N / m] of the propulsion motor 1. In this equation (3), the power consumption P when ωr is the rated speed and τ is the rated torque is called the rated power consumption.
When the ship normally navigates, the speed command ωr * output from the speed setter 11 can take a value from 0 to the rated navigation speed. Further, the limit by the torque limiter 42 is a fixed value and is set to the rated torque. Therefore, the power consumption P can take a value from 0 to the rated power consumption.
JP 2006-166507 A Electrical Engineering Handbook, 6th edition, pages 884 and 885)
It would have been obvious for one of ordinary skill in the art to combine the teachings of MITSUHIMA with the disclosure of CALVERT with a reasonable expectation of success since MITSUSHIMA teaches that the ship can include a torque limiting device so the electric device cannot move past a torque limiting value. The device has a vector control of the inverter and motor based on the speed command. See claims 1-3 and paragraph 1-10.
In regard to claim 3 and 14, Mitsuhima teaches “..3. The method of claim | further comprising: receiving from a user interface, by the power control unit, a new value for the second threshold; and storing as the second threshold, by the power control unit, the new value”. (see FIG. 7 where the torque limiting value is provided as an input based on the rated power consumption; FIG. 7 is a diagram illustrating an example of the characteristics of the torque limiter 42, where the horizontal axis represents the torque command τe * that is the input of the torque limiter, and the vertical axis is the internal torque reference τe * ′ that is the output of the torque limiter. .
The torque of the induction motor 1 for propulsion shown in FIG. 4 can be controlled in proportion to the magnetic flux command Φ2 ′ * and the internal torque reference τe * ′ by the action of the vector control described above. However, in order to control the torque at high speed. In general, a method is used in which Φ2 ′ * is constant and the motor torque is controlled by the internal torque reference τe * ′.
On the other hand, most of the power supplied to the inverters 4 and 5 is consumed by the propulsion induction motor 1. If the efficiency of the propulsion induction motor 1 and the inverters 4 and 5 is ignored, the power consumed by the electric propulsion device is P = ωr × τ (3)
It becomes. Here, P represents power consumption [W], ωr represents the rotational speed [rad / s] of the propulsion motor 1, and τ represents the generated torque [N / m] of the propulsion motor 1. In this equation (3), the power consumption P when ωr is the rated speed and τ is the rated torque is called the rated power consumption.
When the ship normally navigates, the speed command ωr * output from the speed setter 11 can take a value from 0 to the rated navigation speed. Further, the limit by the torque limiter 42 is a fixed value and is set to the rated torque. Therefore, the power consumption P can take a value from 0 to the rated power consumption.
JP 2006-166507 A Electrical Engineering Handbook, 6th edition, pages 884 and 885)
It would have been obvious for one of ordinary skill in the art to combine the teachings of MITSUHIMA with the disclosure of CALVERT with a reasonable expectation of success since MITSUSHIMA teaches that the ship can include a torque limiting device so the electric device cannot move past a torque limiting value. The device has a vector control of the inverter and motor based on the speed command. See claims 1-3 and paragraph 1-10.
In regard to claim 4 and 15, Mitsuhima teaches “..4. The method of claim 1 further comprising: monitoring, by the power control unit, a duration during which the rotational speed of the electric motor is at or below the first threshold and the torque value is at or above a second threshold; wherein determining, by the power control unit, whether the rotational speed of the electric motor is at or below the first threshold and the torque value is at or above the second threshold includes determining, by the power control unit, whether the rotational speed of the electric motor is at or below the first threshold, the torque value is at or above the second threshold, ( In order to solve the above-mentioned problems, the invention described in claim 1 is directed to a propulsion induction motor having one or more windings for driving a propeller of a ship, connected to each winding of the induction motor, and according to vector control. An inverter provided for each winding for converting the power supplied from the inboard bus to the induction motor and supplying the primary current of the induction motor; a speed setter for supplying a speed command signal to the inverter; and the induction motor A speed detector that detects the rotational speed of the inverter, and a speed controller that computes and amplifies an error signal obtained by subtracting the speed detection signal of the speed detector from the speed command signal, and outputs it as a torque command signal for vector control of the inverter; A current detector for detecting a primary current of each winding of the induction motor, and the torque command signal is compared with the torque limit value by comparing the torque command signal with the torque limit value. And a torque limit value setter for outputting a torque limit value to the torque limiter, wherein the inverter performs vector control based on a speed detection signal, a current detection signal, and a torque command signal. It is characterized by performing an operation.
According to a second aspect of the present invention, in the marine inverter system according to the first aspect, the torque limit value command signal output from the torque limit value setting device is provided by a function generator that generates an arbitrary function. And
According to a third aspect of the present invention, in the marine inverter system according to the first or second aspect, the torque limit value command signal output from the torque limit value setter is given by a function of the speed detection signal. Features.
According to a fourth aspect of the present invention, in the marine inverter system according to the first or second aspect, the torque limit value command signal output from the torque limit value setter is given by a function of the speed command signal. Features.
According to the present invention, in a marine inverter system provided with a propulsion induction motor driven by an inverter, it is possible to appropriately suppress the power consumption of the inverter, and the number of operating diesel generators can be minimized. Become.)
and the duration exceeds a third threshold; and wherein in response to determining that the rotational speed of the electric motor 1s at or below the first threshold and the torque value is at or above the second threshold, directing, by the power control unit, the inverter to not supply the power to the electric motor includes in response to determining that the rotational speed of the electric motor is at or below the first threshold, the torque value is at or above the second threshold, and the duration exceeds the third threshold, directing, by the power control unit, the inverter to not supply the power to the electric motor. (see FIG. 4-7 where The inverters 4 and 5 perform vector control calculation based on the torque command signal τe * , the rotational speed detection signal ωr of the propulsion induction motor 1 and the three-phase output current values iu, iv, iw detected by the current detector, The voltage applied to the induction motor 1 is manipulated to control the current flowing through the winding of the propulsion induction motor 1. Electric power consumed by the inverters 4 and 5 is supplied from the inboard bus 8.
In the above description, the number of inverters is two. However, the number of inverters is not limited to two, and the number of inverter induction motors 1 is 1, and the number of inverters is one. The same function is obtained. Further, even if the number of windings of the propulsion induction motor 1 is increased and an inverter is installed for each winding in the same manner as described above, the same function as described above can be obtained. In addition, when such a multi-winding motor is driven by a plurality of inverters, there is an advantage that a degenerate operation is possible when the inverter fails (see Patent Document 1).
In the conventional electric propulsion apparatus shown in FIG. 4, when the inverters 4 and 5 drive the induction motor 1 for propulsion, the inverters 4 and 5 perform vector control. For example, the vector control performs the control calculation and the inverter control of the vector control calculation block diagram of the inverters 4 and 5 shown in FIG. 5 based on the T-type equivalent circuit of the induction motor shown in FIG. The torque can be controlled in proportion to the torque component of the current while maintaining a constant control, and torque control similar to that of a DC motor can be performed (see Non-Patent Document 1).
In the T-type equivalent circuit of the induction motor shown in FIG. 6, V1 is a terminal voltage, I1 is a primary current, R1 is a primary resistance component, α is excitation reactance / (secondary leakage reactance + excitation reactance), and Lσ is primary leakage. Reactance + α × secondary leakage reactance, M ′ is α × excitation reactance, R2 ′ is α × α × secondary resistance component, I2 ′ is secondary current / α, and s is slip.
5, 30 and 31 are proportional elements, 32 is an integral element, 33 and 34 are dividers, 35 and 36 are subtractors, 37 are adders, and 38 and 40 are coordinate converters. , 39 is a current controller, 41 is a power converter, and 42 is a torque limiter.
In the vector control calculation block diagram of the inverters 4 and 5 in FIG. 5, the proportional element 30 multiplies the magnetic flux command Φ2 ′ * by the reciprocal of the M ′ and outputs the primary component magnetization component current command i1d * . The torque limiter 42 limits the torque command τe * to be equal to or less than a predetermined torque limit value, and creates an internal torque reference τe * ′. Divider 33 outputs an internal torque reference .tau.e * 'the magnetic flux command .phi.2' * by dividing by the primary current of the torque component current instruction i1q *. The proportional element 31 'multiplied by the divider 34 output signal magnetic flux command Φ2 the proportional element 31' the R2 in the i1q * and outputs a divided by * slip frequency command .omega.s *. The adder 37 adds the the speed detection signal ωr of the induction motor .omega.s * outputs primary frequency .omega.1 *, the integrator 32 outputs a magnetic flux phase theta * by integrating the .omega.1 *. The coordinate converter 38 is a well-known coordinate converter that converts the detected three-phase output current values iu, iv, and iw of the inverter from the stator coordinate system to the rotating magnetic field coordinate system based on the θ *. The secondary component magnetization component current detection signal i1d and torque component current detection signal i1q are output. Subtracter 35 outputs the error by subtracting i1d from the i1d *, the subtracter 36 outputs the error obtained by subtracting i1q from the i1q *, the current controller 39 is carried out respectively for example a PI control calculation for these errors Voltage commands v1d * and v1q * in the rotating magnetic field coordinate system are output.
The coordinate converter 40 is a well-known coordinate converter for converting v1d * and v1q * from the rotating magnetic field coordinate system to the stator coordinate system based on the θ * , and is a three-phase voltage command Vu for the voltage applied to the induction motor. * , Vv * , Vw * are output. The power converter 41 is, for example, a voltage type PWM inverter, and after converting an AC input voltage to a DC voltage, the DC voltage is converted to an AC voltage and output so that the output voltage becomes the Vu * , Vv * , Vw *. To do.
FIG. 7 is a diagram illustrating an example of the characteristics of the torque limiter 42, where the horizontal axis represents the torque command τe * that is the input of the torque limiter, and the vertical axis is the internal torque reference τe * ′ that is the output of the torque limiter. .
The torque of the induction motor 1 for propulsion shown in FIG. 4 can be controlled in proportion to the magnetic flux command Φ2 ′ * and the internal torque reference τe * ′ by the action of the vector control described above. However, in order to control the torque at high speed. In general, a method is used in which Φ2 ′ * is constant and the motor torque is controlled by the internal torque reference τe * ′.
On the other hand, most of the power supplied to the inverters 4 and 5 is consumed by the propulsion induction motor 1. If the efficiency of the propulsion induction motor 1 and the inverters 4 and 5 is ignored, the power consumed by the electric propulsion device is P = ωr × τ (3)
It becomes. Here, P represents power consumption [W], ωr represents the rotational speed [rad / s] of the propulsion motor 1, and τ represents the generated torque [N / m] of the propulsion motor 1. In this equation (3), the power consumption P when ωr is the rated speed and τ is the rated torque is called the rated power consumption.
When the ship normally navigates, the speed command ωr * output from the speed setter 11 can take a value from 0 to the rated navigation speed. Further, the limit by the torque limiter 42 is a fixed value and is set to the rated torque. Therefore, the power consumption P can take a value from 0 to the rated power consumption.
JP 2006-166507 A Electrical Engineering Handbook, 6th edition, pages 884 and 885
As described above, in the conventional marine inverter system shown in FIGS. 4 and 5, the power consumption takes a value of 0 to the rated power consumption. Therefore, in the inboard electric system shown in FIG. 3, the diesel generators must be operated in a number that can meet the rated power consumption of the electric propulsion unit and other inboard loads. For example, the power generation amount per generator unit is A [kW], the load factor is 80% at maximum, the rated power consumption of the electric propulsion device is B ′ [kW], and the power consumption of other inboard loads is C [kW]. When
A × 0.8 <(B ′ + C) <2 × A × 0.8 (4))
It would have been obvious for one of ordinary skill in the art to combine the teachings of MITSUHIMA with the disclosure of CALVERT with a reasonable expectation of success since MITSUSHIMA teaches that the ship can include a torque limiting device so the electric device cannot move past a torque limiting value. The device has a vector control of the inverter and motor based on the speed command. See claims 1-3 and paragraph 1-10.
Claims 4 and 15 are amended to recite and the primary reference is silent but HUANENG teaches “...determining, by the power control unit, whether a stuck-or-obstructed-propeller
condition is present by determining whether the rotational speed of the electric
motor is at or below a first threshold selected to correspond to a rotational speed
indicative of the propeller being stuck or obstructed and the torque value is at or
above a second threshold indicative of an abnormal torque load; the stuck condition is present”. (see abstract where the turbine is detected as being stuck and about to crash and the motor output is overloaded and the maximum is reached and then a warning signal is provided that the pitch motor is running very high and then a maximum allowable overload torque is reached and then a fault is detected to stop the turbine from moving for repair; A device for preventing propeller jamming of a wind turbine based on a preventive alarm, comprising:
The monitoring module is used to monitor whether the output torque of the pitch motor of the wind turbine is overloaded;
The judgment module is used to monitor the output torque overload of the pitch motor, and further judge the output torque overload of the pitch motor;
If the output torque overload of the pitch motor returns to normal before reaching the maximum allowable overload torque, the pitch system is running normally;
If the output torque overload of the pitch motor reaches the maximum allowable overload torque, and the duration of reaching the maximum allowable overload torque reaches the first threshold, the wind turbine will send an early warning signal to perform maintenance work on the wind turbine or continue to observe the operation of the pitch motor. If the maintenance operation of the wind turbine is completed, the pitch system will operate normally; if the duration of reaching the maximum allowable overload torque reaches the second threshold from the first threshold, the wind turbine will send a fault signal and stop, and the wind turbine will be registered. Machine maintenance, after the maintenance is completed, reset and restart operation.)
It would have been obvious for one of ordinary skill in the art to combine the teachings of HUANENG with the disclosure of CALVERT with a reasonable expectation of success since HUANENG teaches that a wind turbine can be detected as being past the maximum allowable torque. Then an alarm can be provided for maintenance based on the status of the pitch motor and when it goes past that level the turbine is stopped and reset to prevent it from jamming and crashing. This provides an observation improvement and better maintenance of the turbine. See abstract.
In regard to claim 5 and 16, Mitsushima teaches “..5. The method of claim 4 further comprising: receiving from a user interface, by the power control unit, a new value for the third threshold; and storing as the third threshold, by the power control unit, the new value. (The inverters 4 and 5 perform vector control calculation based on the torque command signal τe * , the rotational speed detection signal ωr of the propulsion induction motor 1 and the three-phase output current values iu, iv, iw detected by the current detector, The voltage applied to the induction motor 1 is manipulated to control the current flowing through the winding of the propulsion induction motor 1. Electric power consumed by the inverters 4 and 5 is supplied from the inboard bus 8.
In the above description, the number of inverters is two. However, the number of inverters is not limited to two, and the number of inverter induction motors 1 is 1, and the number of inverters is one. The same function is obtained. Further, even if the number of windings of the propulsion induction motor 1 is increased and an inverter is installed for each winding in the same manner as described above, the same function as described above can be obtained. In addition, when such a multi-winding motor is driven by a plurality of inverters, there is an advantage that a degenerate operation is possible when the inverter fails (see Patent Document 1).
In the conventional electric propulsion apparatus shown in FIG. 4, when the inverters 4 and 5 drive the induction motor 1 for propulsion, the inverters 4 and 5 perform vector control. For example, the vector control performs the control calculation and the inverter control of the vector control calculation block diagram of the inverters 4 and 5 shown in FIG. 5 based on the T-type equivalent circuit of the induction motor shown in FIG. The torque can be controlled in proportion to the torque component of the current while maintaining a constant control, and torque control similar to that of a DC motor can be performed (see Non-Patent Document 1).
In the T-type equivalent circuit of the induction motor shown in FIG. 6, V1 is a terminal voltage, I1 is a primary current, R1 is a primary resistance component, α is excitation reactance / (secondary leakage reactance + excitation reactance), and Lσ is primary leakage. Reactance + α × secondary leakage reactance, M ′ is α × excitation reactance, R2 ′ is α × α × secondary resistance component, I2 ′ is secondary current / α, and s is slip.
5, 30 and 31 are proportional elements, 32 is an integral element, 33 and 34 are dividers, 35 and 36 are subtractors, 37 are adders, and 38 and 40 are coordinate converters. , 39 is a current controller, 41 is a power converter, and 42 is a torque limiter.
In the vector control calculation block diagram of the inverters 4 and 5 in FIG. 5, the proportional element 30 multiplies the magnetic flux command Φ2 ′ * by the reciprocal of the M ′ and outputs the primary component magnetization component current command i1d * . The torque limiter 42 limits the torque command τe * to be equal to or less than a predetermined torque limit value, and creates an internal torque reference τe * ′. Divider 33 outputs an internal torque reference .tau.e * 'the magnetic flux command .phi.2' * by dividing by the primary current of the torque component current instruction i1q *. The proportional element 31 'multiplied by the divider 34 output signal magnetic flux command Φ2 the proportional element 31' the R2 in the i1q * and outputs a divided by * slip frequency command .omega.s *. The adder 37 adds the the speed detection signal ωr of the induction motor .omega.s * outputs primary frequency .omega.1 *, the integrator 32 outputs a magnetic flux phase theta * by integrating the .omega.1 *. The coordinate converter 38 is a well-known coordinate converter that converts the detected three-phase output current values iu, iv, and iw of the inverter from the stator coordinate system to the rotating magnetic field coordinate system based on the θ *. The secondary component magnetization component current detection signal i1d and torque component current detection signal i1q are output. Subtracter 35 outputs the error by subtracting i1d from the i1d *, the subtracter 36 outputs the error obtained by subtracting i1q from the i1q *, the current controller 39 is carried out respectively for example a PI control calculation for these errors Voltage commands v1d * and v1q * in the rotating magnetic field coordinate system are output.
The coordinate converter 40 is a well-known coordinate converter for converting v1d * and v1q * from the rotating magnetic field coordinate system to the stator coordinate system based on the θ * , and is a three-phase voltage command Vu for the voltage applied to the induction motor. * , Vv * , Vw * are output. The power converter 41 is, for example, a voltage type PWM inverter, and after converting an AC input voltage to a DC voltage, the DC voltage is converted to an AC voltage and output so that the output voltage becomes the Vu * , Vv * , Vw *. To do.
FIG. 7 is a diagram illustrating an example of the characteristics of the torque limiter 42, where the horizontal axis represents the torque command τe * that is the input of the torque limiter, and the vertical axis is the internal torque reference τe * ′ that is the output of the torque limiter. .
The torque of the induction motor 1 for propulsion shown in FIG. 4 can be controlled in proportion to the magnetic flux command Φ2 ′ * and the internal torque reference τe * ′ by the action of the vector control described above. However, in order to control the torque at high speed. In general, a method is used in which Φ2 ′ * is constant and the motor torque is controlled by the internal torque reference τe * ′.
On the other hand, most of the power supplied to the inverters 4 and 5 is consumed by the propulsion induction motor 1. If the efficiency of the propulsion induction motor 1 and the inverters 4 and 5 is ignored, the power consumed by the electric propulsion device is P = ωr × τ (3)
It becomes. Here, P represents power consumption [W], ωr represents the rotational speed [rad / s] of the propulsion motor 1, and τ represents the generated torque [N / m] of the propulsion motor 1. In this equation (3), the power consumption P when ωr is the rated speed and τ is the rated torque is called the rated power consumption.
When the ship normally navigates, the speed command ωr * output from the speed setter 11 can take a value from 0 to the rated navigation speed. Further, the limit by the torque limiter 42 is a fixed value and is set to the rated torque. Therefore, the power consumption P can take a value from 0 to the rated power consumption.
JP 2006-166507 A Electrical Engineering Handbook, 6th edition, pages 884 and 885
As described above, in the conventional marine inverter system shown in FIGS. 4 and 5, the power consumption takes a value of 0 to the rated power consumption. Therefore, in the inboard electric system shown in FIG. 3, the diesel generators must be operated in a number that can meet the rated power consumption of the electric propulsion unit and other inboard loads. For example, the power generation amount per generator unit is A [kW], the load factor is 80% at maximum, the rated power consumption of the electric propulsion device is B ′ [kW], and the power consumption of other inboard loads is C [kW]. When
A × 0.8 <(B ′ + C) <2 × A × 0.8 (4))
It would have been obvious for one of ordinary skill in the art to combine the teachings of MITSUHIMA with the disclosure of CALVERT with a reasonable expectation of success since MITSUSHIMA teaches that the ship can include a torque limiting device so the electric device cannot move past a torque limiting value. The device has a vector control of the inverter and motor based on the speed command. See claims 1-3 and paragraph 1-10.
Claims 6-12 and 17-19 are rejected under 35 U.S.C sec. 103 as being unpatentable as obvious in view of Untied States Patent Application Pub. No.: US20120094555A1 to Calverly et al. that was filed in 2009 and in view of United States Patent Application Pub. No.: US20170373502A1 to Gjerpe filed in 2015 and in view of Japanese Patent Pub. No.: JP2009194993A to Mitsushirma that was filed in 2008 and in view of Japanese Patent Pub. No.: JP 5496388 B2 to Anderson assigned to Siemens (US20130270902A1) and in view of Chinese Patent Pub. No.: CN114899799A to Huaneng filed in 202.
In regard to claim 6 and 17, Anderson teaches “...6. The method of claim 1 further comprising: subsequent to determining that the rotational speed of the electric motor is at or below the first threshold and the torque value is at or above the second threshold, setting, by the power control unit, a fuse parameter to indicate a torque fuse is tripped”. (See abstract that recites each bus section includes a connection to a generator and a connection to a thruster drive of the dynamically positioned vessel. The fault protection system includes a fault isolation system which includes for each power system section a bus tie circuit breaker for breaking the connection provided by the bus tie.)
It would have been obvious for one of ordinary skill in the art to combine the teachings of ANDERSON with the disclosure of CALVERT with a reasonable expectation of success since ANDERSON teaches that the ship can include a fault detection system to detect a fault and then open the circuit breakers to isolate a component and if the fault is not present then a reduced power mode can be provided for a generator ride through to prevent a DC voltage drop and a AVR post fault control to prevent the voltage overshoot. See blocks 101-110. However, if it is still present then all breakers are opened and a ride through operation is provided. A second generator may be started and used to provide power with an engine in blocks 112. In this manner, the fault can be isolated.
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In regard to claim 7 and 18, Anderson teaches “...7. The method of claim 6 further comprising: determining, by the power control unit, whether the fuse parameter is set to indicate the torque fuse is tripped; in response to determining that the fuse parameter is set to indicate the torque fuse is tripped, continuing, by the power control unit, to direct the inverter to not supply the power to the electric motor; and in response to determining that the fuse parameter is not set to indicate the torque fuse is tripped, directing, by the power control unit, the inverter to supply power to the electric motor in accordance with a subsequently received indication of throttle level”. (se FIG. 4 where a fault is determined and then a fault has occurred and a circuit breaker is opened and if the fault is still present then all circuit breakers are opened in blocks 101-107; however if the fault is not present the torque is allowed to be provided in a limited manner to prevent overshooting of the voltage in blocks 101-110)
It would have been obvious for one of ordinary skill in the art to combine the teachings of ANDERSON with the disclosure of CALVERT with a reasonable expectation of success since ANDERSON teaches that the ship can include a fault detection system to detect a fault and then open the circuit breakers to isolate a component and if the fault is not present then a reduced power mode can be provided for a generator ride through to prevent a DC voltage drop and a AVR post fault control to prevent the voltage overshoot. See blocks 101-110. However, if it is still present then all breakers are opened and a ride through operation is provided. A second generator may be started and used to provide power with an engine in blocks 112. In this manner, the fault can be isolated.
In regard to claim 8 and 19, Anderson teaches “...8. The method of claim 7 further comprising: receiving from a user interface, by the power control unit, a command indicating a user’s desire to reset the fuse parameter to indicate the torque fuse is not tripped”. (see paragraph 109-112)
It would have been obvious for one of ordinary skill in the art to combine the teachings of ANDERSON with the disclosure of CALVERT with a reasonable expectation of success since ANDERSON teaches that the ship can include a fault detection system to detect a fault and then open the circuit breakers to isolate a component and if the fault is not present then a reduced power mode can be provided for a generator ride through to prevent a DC voltage drop and a AVR post fault control to prevent the voltage overshoot. See blocks 101-110. However, if it is still present then all breakers are opened and a ride through operation is provided. A second generator may be started and used to provide power with an engine in blocks 112. In this manner, the fault can be isolated.
Anderson teaches “9. The method of claim 1 further comprising: receiving from a throttle controller, by the power control unit, an indication of throttle level; and based on the received indication of throttle level, determining, by the power control unit, power supply parameters corresponding to the indication of throttle level; and wherein directing, by a power control unit, an inverter to supply power to an electric motor that drives an electric marine propulsion system of a watercraft includes supplying the power in accordance with the power supply parameters”. (see claim 1-8 where the controller is a variable frequency drive controller to provide the increased thruster drive from the electric motor based on the fault and a drop of the voltage to maintain the voltage above the threshold)
It would have been obvious for one of ordinary skill in the art to combine the teachings of ANDERSON with the disclosure of CALVERT with a reasonable expectation of success since ANDERSON teaches that the ship can include a fault detection system to detect a fault and then open the circuit breakers to isolate a component and if the fault is not present then a reduced power mode can be provided for a generator ride through to prevent a DC voltage drop and a AVR post fault control to prevent the voltage overshoot. See blocks 101-110. However, if it is still present then all breakers are opened and a ride through operation is provided. A second generator may be started and used to provide power with an engine in blocks 112. In this manner, the fault can be isolated.
Anderson teaches “...10. The method of claim 1 further comprising: subsequent to determining that the rotational speed of the electric motor is at or below the first threshold and the torque value is at or above the second threshold, starting, by the power control unit, a timer; determining, by the power control unit, whether a value of the timer exceeds a fourth threshold; in response to determining that the value of the timer does not exceed the fourth threshold, continuing, by the power control unit, to direct the inverter to not supply the power to the electric motor; and in response to determining that the value of the timer exceeds the fourth threshold, directing, by the power control unit, the inverter to supply power to the electric motor in accordance with a subsequently received indication of throttle level”. (see claims 1-14 and paragraph 105-110 where the inverters can be controlled to be off as a fault is present and then the generator may perform a ride through operation in block 118; Parallel to the isolation of the fault by the above measures, steps 108 to 110 are performed, which ensure that the power system 10 stays operational. In step 108, generator ride through protection is performed by preventing excess excitation field currents to be caused by the AVR of the generator that is currently operational. In step 109, thruster drive ride through protection is performed by preventing a voltage drop on the DC bus of the thruster VFD in any of the manners described further above. Consequently, both the running generators as well as the thruster drives stay operational. Furthermore, step 110 provides voltage overshoot limitation after the fault is cleared by reducing the voltage setpoint for the generator in the above described manner. High inrush currents, high torque variations on the prime mover and the tripping of further loads can thus be prevented.
[0111]
The circuit breakers in the remaining power system subsections 11 remain closed during the fault and after clearance of the fault (step 111). Operation is continued. If necessary, additional generators and associated engines are started to provide enough electric power on the power distribution bus 15 (step 112). This may for example be necessary if a running generator is located within the power system subsection 11 that became isolated when clearing the fault.
[0112]
As can be seen from the above description, the disclosed power system and fault protection system may provide an operational safety and protection against faults that makes the system capable of operating with closed bus ties even during high risk operations. The occurrence of a single fault in the power system will not lead to a blackout of the power system, and both, generators and thrusters, remain operational, so that position keeping of the dynamically positioned vessel is maintained. Certain embodiments may thus provide enhanced power system integrity to faults and a reduced risk of blackout of a whole section, since sections are subdivided into subsections. The risk of a total blackout can also be reduced due to the protection scheme and the use of control functionalities by the fault protection system. The enhanced vessel integrity to faults which affect the position keeping enable the operation with closed bus tie breakers in all operational modes, such as DP2 and DP3. This results in reduced fuel costs and a reduced emission of combustion gasses, such as CO2. Furthermore, fewer generators need to be run, resulting in reduced operating hours and maintenance costs for engines and generators. Also, servicing is facilitated, since it is possible to completely shut down the engines and generators of a particular section, and thus perform service without having engines operating in the same engine room. Voltage overshoot prevention and the UPS furthermore result in a reduced risk to loose essential consumers after the occurrence of a fault.)
It would have been obvious for one of ordinary skill in the art to combine the teachings of ANDERSON with the disclosure of CALVERT with a reasonable expectation of success since ANDERSON teaches that the ship can include a fault detection system to detect a fault and then open the circuit breakers to isolate a component and if the fault is not present then a reduced power mode can be provided for a generator ride through to prevent a DC voltage drop and a AVR post fault control to prevent the voltage overshoot. See blocks 101-110. However, if it is still present then all breakers are opened and a ride through operation is provided. A second generator may be started and used to provide power with an engine in blocks 112. In this manner, the fault can be isolated.
Anderson teaches “...11. The method of claim 10 further comprising: receiving from a user interface, by the power control unit, a new value for the fourth threshold; and storing as the fourth threshold, by the power control unit, the new value.( Parallel to the isolation of the fault by the above measures, steps 108 to 110 are performed, which ensure that the power system 10 stays operational. In step 108, generator ride through protection is performed by preventing excess excitation field currents to be caused by the AVR of the generator that is currently operational. In step 109, thruster drive ride through protection is performed by preventing a voltage drop on the DC bus of the thruster VFD in any of the manners described further above. Consequently, both the running generators as well as the thruster drives stay operational. Furthermore, step 110 provides voltage overshoot limitation after the fault is cleared by reducing the voltage setpoint for the generator in the above described manner. High inrush currents, high torque variations on the prime mover and the tripping of further loads can thus be prevented.
[0111]
The circuit breakers in the remaining power system subsections 11 remain closed during the fault and after clearance of the fault (step 111). Operation is continued. If necessary, additional generators and associated engines are started to provide enough electric power on the power distribution bus 15 (step 112). This may for example be necessary if a running generator is located within the power system subsection 11 that became isolated when clearing the fault.
[0112]
As can be seen from the above description, the disclosed power system and fault protection system may provide an operational safety and protection against faults that makes the system capable of operating with closed bus ties even during high risk operations. The occurrence of a single fault in the power system will not lead to a blackout of the power system, and both, generators and thrusters, remain operational, so that position keeping of the dynamically positioned vessel is maintained. Certain embodiments may thus provide enhanced power system integrity to faults and a reduced risk of blackout of a whole section, since sections are subdivided into subsections. The risk of a total blackout can also be reduced due to the protection scheme and the use of control functionalities by the fault protection system. The enhanced vessel integrity to faults which affect the position keeping enable the operation with closed bus tie breakers in all operational modes, such as DP2 and DP3. This results in reduced fuel costs and a reduced emission of combustion gasses, such as CO2. Furthermore, fewer generators need to be run, resulting in reduced operating hours and maintenance costs for engines and generators. Also, servicing is facilitated, since it is possible to completely shut down the engines and generators of a particular section, and thus perform service without having engines operating in the same engine room. Voltage overshoot prevention and the UPS furthermore result in a reduced risk to loose essential consumers after the occurrence of a fault.)
It would have been obvious for one of ordinary skill in the art to combine the teachings of ANDERSON with the disclosure of CALVERT with a reasonable expectation of success since ANDERSON teaches that the ship can include a fault detection system to detect a fault and then open the circuit breakers to isolate a component and if the fault is not present then a reduced power mode can be provided for a generator ride through to prevent a DC voltage drop and a AVR post fault control to prevent the voltage overshoot. See blocks 101-110. However, if it is still present then all breakers are opened and a ride through operation is provided. A second generator may be started and used to provide power with an engine in blocks 112. In this manner, the fault can be isolated.
Applicant's amendment necessitated the new ground(s) of rejection presented in this Office action. Accordingly, THIS ACTION IS MADE FINAL. See MPEP § 706.07(a). Applicant is reminded of the extension of time policy as set forth in 37 CFR 1.136(a).
A shortened statutory period for reply to this final action is set to expire THREE MONTHS from the mailing date of this action. In the event a first reply is filed within TWO MONTHS of the mailing date of this final action and the advisory action is not mailed until after the end of the THREE-MONTH shortened statutory period, then the shortened statutory period will expire on the date the advisory action is mailed, and any nonprovisional extension fee (37 CFR 1.17(a)) pursuant to 37 CFR 1.136(a) will be calculated from the mailing date of the advisory action. In no event, however, will the statutory period for reply expire later than SIX MONTHS from the mailing date of this final action.
Any inquiry concerning this communication or earlier communications from the examiner should be directed to JEAN PAUL CASS whose telephone number is (571)270-1934. The examiner can normally be reached Monday to Friday 7 am to 7 pm; Saturday 10 am to 12 noon.
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/JEAN PAUL CASS/Primary Examiner, Art Unit 3666