Prosecution Insights
Last updated: April 19, 2026
Application No. 18/579,327

THREE-LEVEL CONTROL CIRCUIT, POWER CONVERSION DEVICE, AND CONTROL METHOD THEREOF

Non-Final OA §102§112
Filed
Jan 12, 2024
Examiner
LAXTON, GARY L
Art Unit
2838
Tech Center
2800 — Semiconductors & Electrical Systems
Assignee
Ace Power And Technology Co. Ltd.
OA Round
1 (Non-Final)
86%
Grant Probability
Favorable
1-2
OA Rounds
2y 4m
To Grant
93%
With Interview

Examiner Intelligence

Grants 86% — above average
86%
Career Allow Rate
943 granted / 1090 resolved
+18.5% vs TC avg
Moderate +7% lift
Without
With
+6.6%
Interview Lift
resolved cases with interview
Typical timeline
2y 4m
Avg Prosecution
26 currently pending
Career history
1116
Total Applications
across all art units

Statute-Specific Performance

§101
0.7%
-39.3% vs TC avg
§103
34.8%
-5.2% vs TC avg
§102
40.3%
+0.3% vs TC avg
§112
16.1%
-23.9% vs TC avg
Black line = Tech Center average estimate • Based on career data from 1090 resolved cases

Office Action

§102 §112
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 . Information Disclosure Statement The information disclosure statements submitted are in compliance with the provisions of 37 CFR 1.97. Accordingly, the information disclosure statements are being considered by the examiner. Drawings Figures 1 and 2 should be designated by a legend such as --Prior Art-- because only that which is old is illustrated. See MPEP § 608.02(g). Corrected drawings in compliance with 37 CFR 1.121(d) are required in reply to the Office action to avoid abandonment of the application. The replacement sheet(s) should be labeled “Replacement Sheet” in the page header (as per 37 CFR 1.84(c)) so as not to obstruct any portion of the drawing figures. If the changes are not accepted by the examiner, the applicant will be notified and informed of any required corrective action in the next Office action. The objection to the drawings will not be held in abeyance. The drawings are objected to under 37 CFR 1.83(a). The drawings must show every feature of the invention specified in the claims. Therefore, the inductors connected in series of claim 3 and 12 must be shown or the feature(s) canceled from the claim(s). No new matter should be entered. Corrected drawing sheets in compliance with 37 CFR 1.121(d) are required in reply to the Office action to avoid abandonment of the application. Any amended replacement drawing sheet should include all of the figures appearing on the immediate prior version of the sheet, even if only one figure is being amended. The figure or figure number of an amended drawing should not be labeled as “amended.” If a drawing figure is to be canceled, the appropriate figure must be removed from the replacement sheet, and where necessary, the remaining figures must be renumbered and appropriate changes made to the brief description of the several views of the drawings for consistency. Additional replacement sheets may be necessary to show the renumbering of the remaining figures. Each drawing sheet submitted after the filing date of an application must be labeled in the top margin as either “Replacement Sheet” or “New Sheet” pursuant to 37 CFR 1.121(d). If the changes are not accepted by the examiner, the applicant will be notified and informed of any required corrective action in the next Office action. The objection to the drawings will not be held in abeyance. None of the figures show inductors connected in series. Specification Applicant is reminded of the proper language and format for an abstract of the disclosure. The abstract should be in narrative form and generally limited to a single paragraph on a separate sheet within the range of 50 to 150 words in length. The abstract should describe the disclosure sufficiently to assist readers in deciding whether there is a need for consulting the full patent text for details. The language should be clear and concise and should not repeat information given in the title. It should avoid using phrases which can be implied, such as, “The disclosure concerns,” “The disclosure defined by this invention,” “The disclosure describes,” “The present application provides,” etc. In addition, the form and legal phraseology often used in patent claims, such as “means” and “said,” should be avoided. 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. Claims 1-14 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 1 recites the limitation "the first main line" in line 4. There is insufficient antecedent basis for this limitation in the claim. The applicant claimed two, it is unclear which one is being referenced. Claim 1 recites the limitation "the second main line" in line 4. There is insufficient antecedent basis for this limitation in the claim. The applicant claimed two, it is unclear which one is being referenced. Claim 1 line 7, the phrase "interleaving technology" renders the claim(s) indefinite because the claim(s) include(s) elements not actually disclosed (those encompassed by "technology"), thereby rendering the scope of the claim(s) unascertainable. Claim 1 recites the limitation "the first conversion branches of each of the first main lines" in line 9. There is insufficient antecedent basis for this limitation in the claim. Claim 1 recites the limitation "the capacitor branch" in line 10. There is insufficient antecedent basis for this limitation in the claim. Claim 1 recites the limitation "the third capacitor" in line 11. There is insufficient antecedent basis for this limitation in the claim. Which one? Claim 1 recites the limitation "the fourth capacitor" in line 11. There is insufficient antecedent basis for this limitation in the claim. Which one? Claim 3 recites the limitation "inductors are connected in series" in line 2. This is vague and definite. Does the applicant mean the inductors are in series with each other or each inductor is in series between the branch and line? Claim 3 recites the limitation "the first conversion branch" in line 2. There is insufficient antecedent basis for this limitation in the claim. Claim 3 recites the limitation "the second conversion branch" in line 6. There is insufficient antecedent basis for this limitation in the claim. Claim 4 recites the limitation "T-type or I-type" in lines 2 and 3. T and I are undefined. Claim 5 recites the limitation "a T-type" in line 2. There is insufficient antecedent basis for this limitation in the claim. This was already claimed in claim 4. Claim 5 recites the limitation "at least two controllable semiconductor devices" in line 4. There is insufficient antecedent basis for this limitation in the claim. At least two controllable semiconductor devices were claimed in line 2, are these the same or different two controllable devices? Claims 2-5 inherit the same from claim 1. Claim 6 recites the limitation "the three level control circuit" in line 1. There is insufficient antecedent basis for this limitation in the claim. Claim 6 recites the limitation "the first main line" in line 5. There is insufficient antecedent basis for this limitation in the claim. The applicant claimed two, it is unclear which one is being referenced. Claim 6 recites the limitation "the second main line" in line 5. There is insufficient antecedent basis for this limitation in the claim. The applicant claimed two, it is unclear which one is being referenced. Claim 6 line 8, the phrase "interleaving technology" renders the claim(s) indefinite because the claim(s) include(s) elements not actually disclosed (those encompassed by "technology"), thereby rendering the scope of the claim(s) unascertainable. Claim 6 recites the limitation "the first conversion branches of each of the first main lines" in line 10. There is insufficient antecedent basis for this limitation in the claim. Claim 6 recites the limitation "the capacitor branch" in line 11. There is insufficient antecedent basis for this limitation in the claim. Claim 6 recites the limitation "the other end" in line 15. There is insufficient antecedent basis for this limitation in the claim. Claim 6 recites the limitation "the third capacitor" in line 16. There is insufficient antecedent basis for this limitation in the claim. Which one? Claim 6 recites the limitation "the fourth capacitor" in line 17. There is insufficient antecedent basis for this limitation in the claim. Which one? Claim 6 recites the limitation "the first capacitor" in line 16. There is insufficient antecedent basis for this limitation in the claim. Claim 6 recites the limitation "the second capacitor" in line 16. There is insufficient antecedent basis for this limitation in the claim. Claim 7 recites the limitation "the currents" in line 4. There is insufficient antecedent basis for this limitation in the claim. Claim 8 recites the limitation "the voltage loop" in line 2. There is insufficient antecedent basis for this limitation in the claim. Claim 8 recites the limitation "the charging process" in line 2. There is insufficient antecedent basis for this limitation in the claim. Claim 8 recites the limitation "the discharging process" in line 3. There is insufficient antecedent basis for this limitation in the claim. Claim 9 recites the limitation "the degree difference" in line 2. There is insufficient antecedent basis for this limitation in the claim. Claim 9 recites the limitation "the inverter" in line 2. There is insufficient antecedent basis for this limitation in the claim. Claim 9 recites the limitation "the number" in line 3. There is insufficient antecedent basis for this limitation in the claim. Claim 10 recites the limitation "the low frequency operating state" in line 2. There is insufficient antecedent basis for this limitation in the claim. Claim 10 recites the limitation "the driving level" in line 2. There is insufficient antecedent basis for this limitation in the claim. Claim 10 recites the limitation "the inverters" in line 2. There is insufficient antecedent basis for this limitation in the claim. Claim 12 recites the limitation "an inductor" in line 5. There is insufficient antecedent basis for this limitation in the claim. Line 2 claimed inductors (plural) is this inductor one of the plural inductors or a separate inductor? Claim 12 recites the limitation "the capacitor branch" in line 6. There is insufficient antecedent basis for this limitation in the claim. Claim 12 recites the limitation "the first DC terminal" in line 7. There is insufficient antecedent basis for this limitation in the claim. Claim 12 recites the limitation "the second DC terminal" in line 8. There is insufficient antecedent basis for this limitation in the claim. Claims 13 and 14 recite the limitation "T-type or I-type" in lines 2 and 3. T-type and I-type are undefined. Claim 14 recites the limitation "at least two controllable semiconductor devices" in line 5. There is insufficient antecedent basis for this limitation in the claim. At least two controllable semiconductor devices were claimed in line 4, are these the same or different two controllable devices? 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)(1) the claimed invention was patented, described in a printed publication, or in public use, on sale, or otherwise available to the public before the effective filing date of the claimed invention. (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. Claim(s) 1, 4-6, 13 and 14 is/are rejected under 35 U.S.C. 102a1/a2 as being anticipated by Lai et al. (US 20210281164). As best as the claim language is understood, Claims 1 and 6; Lai et al. fig. 5 disclose a three-level control circuit (VDC+, N, VDC-), characterized in that, the three-level control circuit includes two first main lines (e.g. L_A, L_B) and two second main lines (VDC+/VDC-) between a three-phase port (LA/LB/LC, N) and a two-phase terminal (VDC+, VDC-); the first main line includes a plurality of first conversion branches (L1, Q3/Q4, L2, Q7/Q8), the second main line includes two capacitor branches (C1, C2) and a plurality of second conversion branches (Q1/Q2, Q5/Q6), and the first conversion branches and the second conversion branches are in interleaved; each of the capacitor branches has a third capacitor (C1) and a fourth capacitor (C2) connected in series, the plurality of the first conversion branches of each of the first main lines are respectively connected to correspond to the capacitor branch (C1/C2), and a connection point (N) is located between the third capacitor (C1) and the fourth capacitor (C2). Claim 4; t-type. Claim 5; fig. 2; two controllable switches Q3/Q4 and/or Q7/Q8; intersection at N. Claim 13; t-type. Claim 14; Q3/Q4 or Q7/Q8; intersection at N. Claim(s) 1-7 and 11-14 is/are rejected under 35 U.S.C. 102a1/a2 as being anticipated by (HU et al. (CN 103475248 – IDS). Claim 1; Hu et al. disclose a three-level control circuit and a power conversion device (see description, paragraphs 44-59, 80-89 and 114-123, and figures 2-12): in the three-phase power converter 1100 disclosed in figure 11, A-phase, B-phase and C-phase multi-level power conversion circuits (equivalent to comprising three first main lines and three second main lines) are contained between a right-side three-phase port and a left-side direct-current voltage 1110 (equivalent to the two-phase terminal); each phase multi-level power conversion circuit is as shown in figure 1, and figure 6 is a specific embodiment of figure 1; the power conversion circuit 600 is a three-level bridge arm and comprises three first conversion branches (equivalent to the first main line containing a plurality of first conversion branches); a voltage division circuit 620 (equivalent to the capacitor branch) is connected in series to capacitors C1 and C2 (equivalent to the third and fourth capacitors); three second conversion branches (equivalent to the second main line containing a plurality of second conversion branches); the first conversion branches and the second conversion branches work by means of interleaving parallel connection; the power conversion circuit 600 may be a rectifier circuit or an inverter circuit (equivalent to being connected in an interleaving manner by means of an inverter interleaving technology); and the three first conversion branches are respectively connected to the midpoint of the voltage division circuit. Claim 2; capacitors C2, C3 of figure 13. Claim 3; inductors 640. Claim 4; t-type. Claim 5; e.g. Q2/Q3. Claims 6, 7 and 13; Hu et al. disclose (see figures 6 and 11): the three-phase power converter 1100 comprises a three-phase filter circuit 1160, the three-phase filter circuit 1160 comprising a three-phase filter capacitor; one end of each capacitor is connected to a three-phase alternating-current voltage V_a, V_b and V_c, and the other end is connected to the midpoint of the voltage division circuit; a direct-current bus 610 comprises a first terminal Bus+ and a second terminal Bus-; one end of the three first conversion branches is connected to the lines in parallel by means of an inductor 640, and the three second conversion branches are connected to a direct-current bus 610 in parallel with the voltage division circuit 620; the three-level control circuit is a T-type three-level control circuit; two switch transistors are connected in series on each of the first conversion branches, two switch transistors are connected in series on each of the second conversion branches, and the first conversion branches and the second conversion branches intersect on a one-to one basis to form an intersection node which is located between the switch transistors connected in series on the second conversion branches; the power conversion circuit comprises a drive circuit (equivalent to the control module) for controlling N multi-level bridge arms to operate in a phase interleaved 360/N degree; and the interleaving parallel connection technology can implement automatic current-equalizing of a converter. Claim 11; capacitors C2, C3 of figure 13. Claim 12; inductors 640. Claim 14; switches Q2/Q3; intersection point N. Allowable Subject Matter Claims 8-10 would be allowable if rewritten to overcome the rejection(s) under 35 U.S.C. 112(b) or 35 U.S.C. 112 (pre-AIA ), 2nd paragraph, set forth in this Office action and to include all of the limitations of the base claim and any intervening claims. Conclusion Any inquiry concerning this communication or earlier communications from the examiner should be directed to GARY L LAXTON whose telephone number is (571)272-2079. The examiner can normally be reached Monday-Friday, 8 am-4 pm. 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. /GARY L LAXTON/Primary Examiner, Art Unit 2838 2/05/2026
Read full office action

Prosecution Timeline

Jan 12, 2024
Application Filed
Feb 05, 2026
Non-Final Rejection — §102, §112 (current)

Precedent Cases

Applications granted by this same examiner with similar technology

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POWER CONVERSION CIRCUIT, AND METHOD FOR PRODUCING POWER CONVERTER
2y 5m to grant Granted Apr 14, 2026
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2y 5m to grant Granted Mar 31, 2026
Patent 12592647
MULTIPLE-PORT BIDIRECTIONAL DC-DC CONVERTERS AND CONTROL METHODS THEROF
2y 5m to grant Granted Mar 31, 2026
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2y 5m to grant Granted Mar 24, 2026
Patent 12580472
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2y 5m to grant Granted Mar 17, 2026
Study what changed to get past this examiner. Based on 5 most recent grants.

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Prosecution Projections

1-2
Expected OA Rounds
86%
Grant Probability
93%
With Interview (+6.6%)
2y 4m
Median Time to Grant
Low
PTA Risk
Based on 1090 resolved cases by this examiner. Grant probability derived from career allow rate.

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