DETAILED ACTION
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 .
This action is in response to an application filed on 01/12/2023.
Claims 1-20 are pending for examination.
Claim Rejections - 35 USC § 102
The following is a quotation of the appropriate paragraphs of 35 U.S.C. 102 that form the basis for the rejections under this section made in this Office action:
A person shall be entitled to a patent unless –
(a)(2) the claimed invention was described in a patent issued under section 151, or in an application for patent published or deemed published under section 122(b), in which the patent or application, as the case may be, names another inventor and was effectively filed before the effective filing date of the claimed invention.
Claims 1-3 and 8-13 are rejected under 35 U.S.C. 102 (a) (2) as being anticipated by Anderson et al. (US 2023/0244257 A1 and Anderson hereinafter).
As to Claims 1 and 10, Anderson in its teachings as shown in Fig.1-6 disclose an electric drive system/ a method for use with an electric drive system, the method comprising: comprising:
a direct current (24) power supply;
a rotary electric machine (14) connectable to a load;
a power inverter module (60) comprising:
a bulk capacitor (62) connected to the DC power supply; and
a plurality of power switches (64 of 60) having an output side connected to the rotary electric machine (14) and an input side connected to the bulk capacitor (62); and
a controller (63) programmed, in response to an enabling condition, to estimate (thermal model) an internal temperature of the bulk capacitor as an estimated internal temperature, and to selectively derate the rotary electric machine in response to the estimated internal temperature (the DC-link capacitor thermal model is intended to enable the electric drive system to be de-rated only when DC-link capacitor 62 and components of inverter 60 overheat – see [0046]).
As to Claim 2, Anderson disclose the electric drive system of claim 1, wherein: the DC power supply includes a traction battery pack (24) for use aboard a motor vehicle (12); the electric machine includes an electric traction motor (14); and the load includes one or more road wheels (22) of the motor vehicle (see [0029] – [0030]).
As to Claim 3 and 13, Anderson disclose the electric drive system of claim 2 and the method of claim 12, wherein the enabling condition is a key-on event of the motor vehicle, and wherein the controller is configured to: record the estimated internal temperature as a recorded key-off temperature in response to a key-off event of the motor vehicle, wherein the key-off event places the motor vehicle into an OFF operating state; and temporarily estimate the internal temperature of the PIM using the recorded key-off temperature while the motor vehicle is in an OFF operating state (see [0058]-[0070]).
As to Claim 8, Anderson disclose the electric drive system of claim 1, wherein the controller includes a thermal model of the bulk capacitor, the thermal model including a cross-coupled network of temperature nodes of the bulk capacitor and the PIM, and wherein the controller is configured to estimate the internal temperature of the bulk capacitor using the thermal model (see [0046] - [0053]).
As to Claim 9, Anderson disclose the electric drive system of claim 1, wherein the PIM includes a plurality of PIMs and the rotary electric machine includes a plurality of rotary electric machines each connected to a corresponding one of the PIMs, and wherein the controller is configured to allocate an output torque from each respective one of the rotary electric machines to at least one load based at least in part on the estimated internal temperature of the bulk capacitor (see [0046] and [0066] – [0067]).
As to Claim 11, Anderson disclose the method of claim 10, wherein selectively derating the rotary electric machine includes limiting a maximum output torque and/or speed of the rotary electric machine (see [0046]).
As to Claim 12, Anderson disclose the method of claim 11, wherein the rotary electric machine includes an electric traction motor (14) and the load includes one or more road wheels (22) of a motor vehicle (see [0029]).
Allowable Subject Matter
Claim 19-20 is allowed.
The following is an examiner’s statement of reasons for allowance:
As to Claim 19: In view of the limitations the closest prior art (US 2023/0244257 A1) including the prior works of the assignee/inventor does not explicitly describe or reasonably suggest or render obvious in combination with all the given limitations a method for use with an electric drive system of a motor vehicle, the method comprising: selectively derating a maximum torque and/or speed of the polyphase rotary electric machine, via switching control a plurality of power switches of the PIM, in response to the estimated internal temperature, wherein estimating the internal temperature of the bulk capacitor includes: extracting a capacitor current ratio from a two-dimensional lookup table that relates a modulation index of the PIM and a power factor of the PIM to the capacitor current ratio; calculating a root mean square (RMS) current of the capacitor using the capacitor current ratio; determining a power loss value of the bulk capacitor using a thermal model of the bulk capacitor and a power loss model of the bulk capacitor, the power loss model having a set of input signals including a switching frequency of the power switches, a modulation index of the PIM, a power factor of the PIM, a d-axis current command, a q-axis current command, a DC voltage from the DC traction battery pack, and a predetermined pulse width modulation (PWM) strategy; and estimating the internal temperature of the bulk capacitor using the RMS current and the power loss value as claimed by the applicant. In the examiner’s opinion, the claims are now deemed to be directed to a non-obvious improvement over selective motor derating using estimated internal temperature of inverter bulk capacitor.
Claims 4-7 and 14-18 are objected to as being dependent upon a rejected base claim, but would be allowable if rewritten in independent form including all of the limitations of the base claim and any intervening claims.
As to Claims 4 and 14, in view of the limitations the closest prior art including the prior works of the assignee/inventor does not explicitly describe or reasonably suggest or render obvious in combination with all the given limitations the electric drive system/method: wherein the controller is programmed with a two-dimensional lookup table that relates a modulation index of the PIM and a power factor of the PIM to a capacitor current ratio, and the controller is configured to estimate a root mean square (RMS) current of the capacitor using the capacitor current ratio, and to estimate the internal temperature of the bulk capacitor using the RMS current of the capacitor.
As to Claims 5-7 and 15-18, in view of the limitations the closest prior art including the prior works of the assignee/inventor does not explicitly describe or reasonably suggest or render obvious in combination with all the given limitations the electric drive system/method: wherein the controller is programmed to control an ON/OFF switching state of the power switches using a predetermined pulse width modulation (PWM) strategy, and to estimate the internal temperature of the PIM using a scalar factor selected from a one-dimensional lookup table based on the predetermined PWM strategy.
Conclusion
The prior art made of record and not relied upon is considered pertinent to applicant's disclosure (US 2024/0109434 A1: After start of an electric drive system, a controller reduces power output of an inverter responsive to sensed temperature of a power switch of the inverter, sensed current of a power electronics module, sensed DC-link voltage, and thermal impedance parameters of a DC-link capacitor being indicative of an estimated temperature of the DC-link capacitor that is greater than a threshold to maintain DC-link capacitor temperature lower than the threshold – see [Abstract]).
Any inquiry concerning this communication or earlier communications from the examiner should be directed to GABRIEL T AGARED whose telephone number is (571)270-1981. The examiner can normally be reached 8-5 (Mon- Thur).
Examiner interviews are available via telephone, in-person, and video conferencing using a USPTO supplied web-based collaboration tool. To schedule an interview, applicant is encouraged to use the USPTO Automated Interview Request (AIR) at http://www.uspto.gov/interviewpractice.
If attempts to reach the examiner by telephone are unsuccessful, the examiner’s supervisor, Eduardo Colon-Santana can be reached at 5712722060. The fax phone number for the organization where this application or proceeding is assigned is 571-273-8300.
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/GABRIEL AGARED/Primary Examiner, Art Unit 2846
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