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 .
Priority
Receipt is acknowledged of certified copies of papers required by 37 CFR 1.55.
Information Disclosure Statement
The information disclosure statement submitted on 20 Dec 2024 is in compliance with the provisions of 37 CFR 1.97. Accordingly, the information disclosure statement is being considered by the examiner.
Specification
The lengthy specification has not been checked to the extent necessary to determine the presence of all possible minor errors. Applicant’s cooperation is requested in correcting any errors of which applicant may become aware in the specification.
Claim Objections
Claims 1-12 are objected to because of the following informalities:
Claim 1: recites the limitation “the reference vectors”. There is insufficient antecedent basis for this limitation in the claim.
Claims 7-8 suffer from the same deficiency.
Claim 8: recites the limitation “the reference vector” (singular). There is insufficient antecedent basis for this limitation in the claim.
Claims 2-12 are objected to on the basis of their dependency to Claim 1.
Claim 2: recites the limitation “the bridge arms”. There is insufficient antecedent basis for this limitation as it is not consistent with “four bridge arms” recited in claim 1.
Claim 10 recites “each bridge arm” and suffers from the same deficiency.
Claim 11 & 12 recite “the bridge arms” and suffer from the same deficiency.
Claim 12 recites “four bridge arms” without the definite article “the” despite the antecedent basis already established in claim 1.
Claim 3 depends from Claim 2, Claim 12 depends from Claim 11, and thus each at least have the same defect(s).
Claim 2: restates a limitation from claim 1 (“the determining a voltage vector corresponding to a three-phase voltage”) using the same indefinite articles (“a”) originally used to introduce that limitation in claim 1, rather than switching to definite articles (“the”) for limitations that already have antecedent basis (i.e. “the voltage vector”).
Claims 4, 7, 9, 10, 11, & 12 suffer from the same type of deficiency.
Claim 3 depends from Claim 2, Claim 5 depends from Claim 4, Claims 8-9 depend from Claim 7, Claim 12 depends from Claim 11, and thus each at least have the same defect(s).
Claim 3: recites “an A bridge arm”, “an N bridge arm”, “a B bridge arm”, and “a C bridge arm” without reciting that these are the “four bridge arms” of claim 1.
Claim 5 recites “the A bridge arm”, “the N bridge arm”, “the B bridge arm”, and “the C bridge arm”. There is insufficient antecedent basis for this limitation as it is not consistent with “four bridge arms” recited in claim 1. Additionally, these elements were introduced in claim 3, which does not fall within the dependency chain of claim 5.
Claim 3: recites the limitation “a voltage vector” three times, which is not consistent with “the voltage vector” of claims 1-3, and does not clarify whether UAN, UBN, and UCN are three newly-introduced component vectors or repeated recitations of the single, previously-claimed voltage vector.
Claim 4: recites the limitation “the standardized voltage vectors”. There is insufficient antecedent basis for this limitation in the claim.
Claim 5: recites “a standardized voltage vector of the A bridge arm”, “a standardized voltage vector of the B bridge arm”, “a standardized voltage vector of the C bridge arm”, without reciting that these are the “the standardized voltage vectors” of claim 4.
Claim 5 is objected to on the basis of its dependency to Claim 4.
Claim 4: recites the limitation “the voltage vectors” (plural). There is insufficient antecedent basis for this limitation in the claim.
Claim 5 is objected to on the basis of its dependency to Claim 4.
Claim 6: recites the limitation “imagery”, which appears to be a typographical error for “imaginary”.
Claim 9: depends from claim 7, which recites “positioning the preset reference vectors in the cubic regions”, which places vectors inside of regions that are cube-shaped but does not select or position a cube itself as a discrete claimed entity. Claim 9 then refers to “a positioned target cube”, but neither claim 7 nor claim 1 establishes that a cube is identified, selected, or positioned as such. Claim 8 has a cube-selection step that would allow Claim 9 to naturally follow it by either including those limitations in Claim 9 or having Claim 9 be dependent on Claim 8.
Claim 11: recites the limitations “determining a duty ratio” (singular) and “multiplying the duty ratio” (singular), but the formula defines “d1-4” (plural, four values) as “the duty ratios” (plural), which is an inconsistent singular/plural use of “duty ratio(s)”.
Claim 12 is objected to on the basis of its dependency to Claim 11.
Appropriate correction is required.
Claim Rejections - 35 USC § 112
The following is a quotation of 35 U.S.C. 112(b):
(b) CONCLUSION.—The specification shall conclude with one or more claims particularly pointing out and distinctly claiming the subject matter which the inventor or a joint inventor regards as the invention.
The following is a quotation of 35 U.S.C. 112 (pre-AIA ), second paragraph:
The specification shall conclude with one or more claims particularly pointing out and distinctly claiming the subject matter which the applicant regards as his invention.
Claim 9 is rejected under 35 U.S.C. 112(b) or 35 U.S.C. 112 (pre-AIA ), second paragraph, as being indefinite for failing to particularly point out and distinctly claim the subject matter which the inventor or a joint inventor (or for applications subject to pre-AIA 35 U.S.C. 112, the applicant), regards as the invention.
Claim 9: recites the limitations ”origin coordinates”, “the reference origin coordinates”, and “an origin”. The limitation “reference origin coordinates” is first introduced in Claim 8, but Claim 8 is not in Claim 9’s dependency chain. It is unclear as to whether “origin coordinates”, “the reference origin coordinates”, and “origin” are referring to the same origin. For the purposes of examination, the examiner interprets the above limitations to refer to the same origin point.
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.
Claims 1-11 are rejected under 35 U.S.C. 103 as being unpatentable over Franquelo ("Three-dimensional space-vector modulation algorithm for four-leg multilevel converters using abc coordinates") in view of Rojas ("A New Space-Vector-Modulation Algorithm for a Three-Level Four-Leg NPC Inverter").
Regarding Claim 1, Franquelo discloses a voltage regulation method for a three-phase four-bridge-arm three-level inverter (Fig 1), comprising: determining a voltage vector corresponding to a three-phase voltage ("SVM is used to approximate a reference voltage vector uref", "three-phase coordinates (uan, ubn, ucn)", section II. A. column 1 lines 2-3 and column 2 lines 3-4); constructing a controllable spatial polyhedral region on the basis of an abc three-dimensional coordinate system and the voltage vector ("The space vectors of a four-leg multilevel converter form a dodecahedron in a 3-D space. This space can be decomposed into several cubes, where six tetrahedrons generate the total volume of each cube. The 3-D dodecahedron containing the state vectors that generate the reference vector in four-leg three-level converter", section II. A. column 1 last 7 lines); positioning preset reference vectors in a plurality of sub-regions of the controllable spatial polyhedral region ("The space vectors of a four-leg multilevel converter form a dodecahedron in a 3-D space. This space can be decomposed into several cubes, where six tetrahedrons generate the total volume of each cube.", "Six tetrahedrons are considered in each subcube. Therefore, it is necessary to define the tetrahedron where the reference vector is pointing to. This tetrahedron is easily found using comparisons with three 45◦ planes into the 3-D space, which define the six tetrahedrons inside the subcube.", Fig 2, section II. A. Steps 1-2), so as to generate reference voltage vectors corresponding to the reference vectors ("the main step of the algorithm consists in calculating the four space vectors corresponding to the four vertices of a tetrahedron into the selected subcube...", section II. A. Step 3), wherein the reference voltage vectors are used for controlling output states of corresponding four bridge arms ("These vectors will generate the reference vector.", section II. A. Step 3).
Franquelo does not disclose sorting the reference voltage vectors with a modulation strategy in which a zero-level output state is reduced; and generating a switching pulse sequence of the bridge arms according to the sorted reference voltage vectors and a corresponding action time, so as to regulate a midpoint voltage of the three- phase four-bridge-arm three-level inverter.
Rojas teaches a conventional SVM algorithm for use in a three-phase four-bridge-arm three-level inverter (see Fig 1) including sorting the reference voltage vectors with a modulation strategy in which a zero-level output state is reduced ("The redundant vectors are those formed by two different switching combinations … For each pair of redundant vectors, the current io … has the same magnitude but opposite direction, this allows the voltage balance on the dc-link capacitors to be controlled.", section II. B. last 5 lines of p24-first line of p25); and generating a switching pulse sequence of the bridge arms according to the sorted reference voltage vectors ("a pulse width modulation technique is applied, at each sample time, to the redundant vectors" section II. G. lines 8-9) and a corresponding action time (Equations 8-9 & 11 calculate the duty cycles and sub-duty cycles, section II. E. & G.), so as to regulate a midpoint voltage of the three-phase four-bridge-arm three-level inverter ("in order to modulate the neutral point current io to track a reference current (i∗o) and balance the voltages on the dc-link capacitors VC1 and VC2 ." , Fig 1, section II. G. lines 9-11).
It would have been obvious to a person of ordinary skill in the art before the effective filing date of the claimed invention to have optionally included the SVM algorithm in Franquelo, as taught by Rojas, as it provides the advantage of actively balancing the dc-link capacitor voltages using the redundancies of the converter states, without additional hardware (abstract of Rojas).
Regarding Claim 4, the combination of Franquelo and Rojas discloses all of the limitations of claim 1, and further discloses wherein the constructing a controllable spatial polyhedral region on the basis of an abc three-dimensional coordinate system and the voltage vector comprises: standardizing the voltage vector ("The modulation algorithm input is the normalized voltage vector. The normalization only depends on the number of levels of the multilevel converter n and the voltage level value of the dclink capacitors, Vdc [5]. In general, the reference vector must be scaled by the normalization constant: Vdc/(n − 1)", section II. A. of Franquelo); and introducing the standardized voltage vectors into the abc three-dimensional coordinate system to construct the controllable spatial polyhedral region ("The space vectors of a four-leg multilevel converter form a dodecahedron in a 3-D space…For a certain reference vector in three-phase coordinates (uan, ubn, ucn), the integer part of each component (a, b, c) is calculated…", section II. A. Step 1 of Franquelo).
Regarding Claim 6, the combination of Franquelo and Rojas discloses all of the limitations of claim 1, and further discloses wherein the controllable spatial polyhedral region is a controllable dodecahedral region ("The proposed 3-D-SVM algorithm easily calculates the four state vectors that generate the reference vector in four-leg multilevel power converter systems. In this way, it is necessary to use a switching sequence with four state vectors. Thus, the reference vector will be pointing to a volume, which is a tetrahedron, into a cube of the dodecahedron.", section II. A. p459 of Franquelo), the controllable dodecahedral region comprising three cubic regions constructed by standardized voltage vectors (the normalized voltage vector is the input to the modulation algorithm and three cubes of the controllable dodecahedron are shown in Fig 2, Fig 2, section II. A. p459 of Franquelo) and six imagery cubic regions attached to the outer sides of the three cubic regions ("there are another subcubes located between the cubes and each plane dodecahedron that also belong to the control space. They must be taken into account in the modulation algorithm.", Fig 2, section II. A. Step 1 of Franquelo).
Regarding Claim 7, the combination of Franquelo and Rojas discloses all of the limitations of claim 1, and further discloses wherein the positioning preset reference vectors in a plurality of sub-regions of the controllable spatial polyhedral region, so as to generate reference voltage vectors corresponding to the reference vectors comprises: positioning the preset reference vectors in the cubic regions of the plurality of sub-regions of the controllable spatial polyhedral region ("Calculate the coordinates of the subcube reference vertex where the reference vector is found. The space vectors of a four-leg multilevel converter form a dodecahedron in a 3-D space. This space can be decomposed into several cubes, where six tetrahedrons generate the total volume of each cube.", section II. A. Step 1 of Franquelo); positioning the preset reference vectors in tetrahedral regions of the plurality of sub-regions of the controllable spatial polyhedral region ("Six tetrahedrons are considered in each subcube. Therefore, it is necessary to define the tetrahedron where the reference vector is pointing to. This tetrahedron is easily found using comparisons with three 45◦ planes into the 3-D space, which define the six tetrahedrons inside the subcube.", section II. A. Step 2 of Franquelo); and generating reference voltage vectors corresponding to the reference vectors according to a final positioning result ("Once (a, b, c) coordinates are known, the main step of the algorithm consists in calculating the four space vectors corresponding to the four vertices of a tetrahedron into the selected subcube... These vectors will generate the reference vector." and "Thus, the reference vector will be pointing to a volume, which is a tetrahedron, into a cube of the dodecahedron.", section II. A. p459-460 of Franquelo).
Regarding Claim 8, the combination of Franquelo and Rojas discloses all of the limitations of claim 7, and further discloses wherein the positioning the preset reference vectors in the cubic regions of the plurality of sub-regions of the controllable spatial polyhedral region comprises: selecting a cube where reference origin coordinates are located from the controllable spatial polyhedral region based on the reference origin coordinates after rounding of the reference vectors ("Calculate the coordinates of the subcube reference vertex where the reference vector is found. The space vectors of a four-leg multilevel converter form a dodecahedron in a 3-D space. This space can be decomposed into several cubes, where six tetrahedrons generate the total volume of each cube.", section II. A. Step 1 of Franquelo), wherein the reference origin coordinates are:
PNG
media_image1.png
101
200
media_image1.png
Greyscale
in which: u*ran represents a-axis coordinates of the reference vector; u*rbn represents b-axis coordinates of the reference vector; and u*crn represents c-axis coordinates of the reference vector ("For a certain reference vector in three-phase coordinates (uan, ubn, ucn), the integer part of each component (a, b, c) is calculated, where a =integer(uan) b =integer(ubn) c =integer(ucn)" and "The coordinates (a, b, c) are the origin coordinates corresponding to the reference system of the subcube where the reference vector is pointing to.", section II. A. p459-460 of Franquelo).
Regarding Claim 9, the combination of Franquelo and Rojas discloses all of the limitations of claim 7, and further discloses wherein the positioning the preset reference vectors in the tetrahedral regions of the plurality of sub-regions of the controllable spatial polyhedral region comprises: a positioned target cube is divided by three 45 degree sections by taking origin coordinates corresponding to the reference vectors as a reference point; distances among the three sections are calculated with the reference origin coordinates as a center to determine a tetrahedron position where the reference vector is located ("Six tetrahedrons are considered in each subcube. Therefore, it is necessary to define the tetrahedron where the reference vector is pointing to. This tetrahedron is easily found using comparisons with three 45◦ planes into the 3-D space, which define the six tetrahedrons inside the subcube. The three planes that define the six tetrahedrons are shown in Fig. 5. Notice that only a maximum of three comparisons are needed regardless the converter number of levels.", section II. A. Step 2 of Franquelo); and the three 45 degree sections comprise an a-b-axis 45 degree section, a c-b-axis 45 degree section and an a-c-axis 45 degree section that pass through an origin ("Planes used for selecting the tetrahedron where the reference vector is pointing to.", Fig 5, section II. A. p460 of Franquelo).
Regarding Claim 10, the combination of Franquelo and Rojas discloses all of the limitations of claim 1, and further discloses wherein the sorting the reference voltage vectors with a modulation strategy in which a zero-level output state is reduced comprises: determining a synthesis sequence of the reference voltage vectors in the controllable spatial polyhedral region ("Once the vectors are selected, the sequence can be chosen to minimize the number of commutations.", p461 of Franquelo); and adjusting a sequence of the reference voltage vectors with a goal of reducing a midpoint current into each bridge arm ("an active control methodology, embedded into the utilisation and selection of the SVM redundant vectors, is proposed to balance the capacitor voltages. According to this, a pulse width modulation technique is applied, at each sample time, to the redundant vectors in order to modulate the neutral point current io to track a reference current (i∗o ) and balance the voltages on the dc-link capacitors VC1 and VC2 .", p28 Section G. of Rojas).
Regarding Claim 11, the combination of Franquelo and Rojas discloses all of the limitations of claim 1, and further discloses wherein the generating a switching pulse sequence of the bridge arms according to the sorted reference voltage vectors and a corresponding action time comprises: determining a duty ratio corresponding to the reference voltage vectors according to the following formula:
PNG
media_image2.png
129
414
media_image2.png
Greyscale
(Equation 3, p461 of Franquelo) multiplying the duty ratio by a switching period to obtain the action time corresponding to the reference voltage vectors ("ti = diTm, i= 1, . . . , 4 where Tm is the sample time.", p460 of Franquelo); in which, (S1an, S1bn, S1cn), (S2an, S2bn, S2cn), (S3an, S3bn, S3cn), and (S4an, S4bn, S4cn) are tetrahedral fixed-point coordinates where the reference voltage vectors are located, and d1-4 are the duty ratios of the reference voltage vectors (see Equation 2 where the S matrix contains the coordinates of each state vector and di is the corresponding duty cycle, p460 of Franquelo); and generating the switching pulse sequence of the bridge arms according to the sorted reference voltage vectors and the corresponding action time ("The algorithm generates a matrix S with four state vectors and the corresponding switching times ti.", p460 of Franquelo).
Claim 2 is rejected under 35 U.S.C. 103 as being unpatentable over Franquelo ("Three-dimensional space-vector modulation algorithm for four-leg multilevel converters using abc coordinates") in view of Rojas ("A New Space-Vector-Modulation Algorithm for a Three-Level Four-Leg NPC Inverter"), and further in view of Wang (CN 104377977 A).
Regarding Claim 2, the combination of Franquelo and Rojas discloses all of the limitations of claim 1.
The combination of Franquelo and Rojas does not disclose wherein the determining a voltage vector corresponding to a three-phase voltage comprises: determining the voltage vector corresponding to the three-phase voltage according to output states of the bridge arms, the output states comprising a high level, a zero level and a low level.
Wang teaches a conventional three-level switching state function for use in a three-phase four-bridge-arm three-level inverter (see Fig 1) including wherein the determining a voltage vector corresponding to a three-phase voltage comprises: determining the voltage vector corresponding to the three-phase voltage according to output states of the bridge arms (switching states are 1, 0, and -1, Equation 1), the output states comprising a high level, a zero level and a low level ("After removing redundant vectors, each phase arm has three different vectors, corresponding to three different voltage levels: Vc, 0, and -Vc.", [0072]).
It would have been obvious to a person of ordinary skill in the art before the effective filing date of the claimed invention to have optionally included the three-level switching state function in Franquelo, as taught by Wang, as it provides the advantage of being a simple and direct definition of the abc-coordinate voltage vector (abstract of Wang).
Claim 3 is rejected under 35 U.S.C. 103 as being unpatentable over Franquelo ("Three-dimensional space-vector modulation algorithm for four-leg multilevel converters using abc coordinates") in view of Rojas ("A New Space-Vector-Modulation Algorithm for a Three-Level Four-Leg NPC Inverter"), and further in view of Wang (CN 104377977 A) and Yao ("Three-Dimensional Space Vector Modulation for a Four-Leg Three-Level Inverter").
Regarding Claim 3, the combination of Franquelo, Rojas, and Wang discloses all of the limitations of claim 2.
The combination of Franquelo, Rojas, and Wang does not disclose wherein the determining the voltage vector corresponding to the three-phase voltage according to output states of the bridge arms comprises: determining the voltage vector corresponding to the three-phase voltage according to the following formula:
PNG
media_image3.png
141
187
media_image3.png
Greyscale
in which: UAN represents a voltage vector of an A bridge arm relative to an N bridge arm; UBN represents a voltage vector of a B bridge arm relative to the N bridge arm; UCN represents a voltage vector of a C bridge arm relative to the N bridge arm; Si(i=a,b,c,n) =
PNG
media_image4.png
80
166
media_image4.png
Greyscale
Sa, Sb, Sc and Sn are output states of A, B, C and N bridge arms of the three-phase four-bridge-arm three-level inverter respectively; and Udc represents a DC-side power voltage.
It would have been obvious to a person of ordinary skill in the art before the effective filing date of the claimed invention to have optionally included the phase-to-N-bridge-arm voltage formula in Franquelo, as taught by Yao, as it provides the advantage of fully utilizing the dc link voltage, reducing voltage ripple, and improved balance of the dc link capacitors
Yao teaches a conventional phase-to-N-bridge-arm voltage formula for use in a three-phase four-bridge-arm three-level inverter (see Fig 2) including wherein the determining the voltage vector corresponding to the three-phase voltage according to output states of the bridge arms comprises: determining the voltage vector corresponding to the three-phase voltage according to the following formula:
PNG
media_image3.png
141
187
media_image3.png
Greyscale
in which: UAN represents a voltage vector of an A bridge arm relative to an N bridge arm (vad=Sa-Sd * Vdc/2, Equation 1); UBN represents a voltage vector of a B bridge arm relative to the N bridge arm (vbd=Sb-Sd * Vdc/2, Equation 1); UCN represents a voltage vector of a C bridge arm relative to the N bridge arm (vcd=Sc-Sd * Vdc/2, Equation 1); Si(i=a,b,c,n) =
PNG
media_image4.png
80
166
media_image4.png
Greyscale
Sa, Sb, Sc and Sn are output states of A, B, C and N bridge arms of the three-phase four-bridge-arm three-level inverter respectively (levels 2 [high], 1 [zero], and 0 [low], Equation 2); and Udc represents a DC-side power voltage (Vdc is the DC link voltage, p3 lines 9-10).
It would have been obvious to a person of ordinary skill in the art before the effective filing date of the claimed invention to have optionally included the phase-to-N-bridge-arm voltage formula in Franquelo, as taught by Yao, as it provides the advantage of fully utilizing the dc link voltage, reducing voltage ripple, and improved balance of the dc link capacitors (p3 lines 1-7 of Yao).
Claim 5 is rejected under 35 U.S.C. 103 as being unpatentable over Franquelo ("Three-dimensional space-vector modulation algorithm for four-leg multilevel converters using abc coordinates") in view of Rojas ("A New Space-Vector-Modulation Algorithm for a Three-Level Four-Leg NPC Inverter"), and further in view of Yao ("Three-Dimensional Space Vector Modulation for a Four-Leg Three-Level Inverter").
Regarding Claim 5, the combination of Franquelo and Rojas discloses all of the limitations of claim 4, and further discloses a standardized voltage vector for each arm ("the reference vector must be scaled by the normalization constant: Vdc/(n − 1)", section II. A. of Franquelo).
The combination of Franquelo and Rojas does not disclose wherein the standardizing the voltage vectors comprises: standardizing the voltage vectors according to the following formula:
PNG
media_image5.png
143
365
media_image5.png
Greyscale
U*AN represents a standardized voltage vector of the A bridge arm relative to the N bridge arm; U*BN represents a standardized voltage vector of the B bridge arm relative to the N bridge arm; and U*CN represents a standardized voltage vector of the C bridge arm relative to the N bridge arm.
Yao teaches a conventional phase-to-N-bridge-arm voltage formula for use in a three-phase four-bridge-arm three-level inverter (see Fig 2) including wherein the standardizing the voltage vectors comprises: standardizing the voltage vectors according to the following formula:
PNG
media_image5.png
143
365
media_image5.png
Greyscale
U*AN represents a standardized voltage vector of the A bridge arm relative to the N bridge arm; U*BN represents a standardized voltage vector of the B bridge arm relative to the N bridge arm; and U*CN represents a standardized voltage vector of the C bridge arm relative to the N bridge arm (when Equation 1 is scaled by the normalization constant of Franquelo it becomes vad/(Vdc/2)=Sa-Sd, vbd/(Vdc/2)=Sb-Sd, and vcd/(Vdc/2)=Sc-Sd, Equation 1).
It would have been obvious to a person of ordinary skill in the art before the effective filing date of the claimed invention to have optionally included the phase-to-N-bridge-arm voltage formula in Franquelo, as taught by Yao, as it provides the advantage of fully utilizing the dc link voltage, reducing voltage ripple, and improved balance of the dc link capacitors (p3 lines 1-7 of Yao).
Allowable Subject Matter
Claim 12 is 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.
Conclusion
The prior art made of record and not relied upon is considered pertinent to applicant's disclosure.
Li (CN 104038091 A) discloses a SVPWM-based DC-side midpoint-voltage-balance control method for a three-level converter with 7-segment symmetric vector-sending order.
Any inquiry concerning this communication or earlier communications from the examiner should be directed to JENNIFER C CAULK whose telephone number is (571)270-0623. The examiner can normally be reached M-F 8:30-5:30, every other Fri off.
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, Crystal Hammond can be reached at (571) 270-1682. The fax phone number for the organization where this application or proceeding is assigned is 571-273-8300.
Information regarding the status of published or unpublished applications may be obtained from Patent Center. Unpublished application information in Patent Center is available to registered users. To file and manage patent submissions in Patent Center, visit: https://patentcenter.uspto.gov. Visit https://www.uspto.gov/patents/apply/patent-center for more information about Patent Center and https://www.uspto.gov/patents/docx for information about filing in DOCX format. For additional questions, contact the Electronic Business Center (EBC) at 866-217-9197 (toll-free). If you would like assistance from a USPTO Customer Service Representative, call 800-786-9199 (IN USA OR CANADA) or 571-272-1000.
J.C.C./Examiner, Art Unit 2838
/GARY L LAXTON/Primary Examiner, Art Unit 2838 7/30/2026
Prosecution Insights