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 (IDS) submitted on 03/11/2024 and 01/08/2026 are in compliance with the provisions of 37 CFR 1.97. Accordingly, the information disclosure statement is being considered by the examiner.
Claim Objections
Claims 1-7 are objected to because of the following informalities:
In claim 1, line 3, delete “rectifier, ,” and replace with “rectifier,”
Appropriate correction is required.
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.
Claim(s) 1-4, 7-11 is/are rejected under 35 U.S.C. 103 as being unpatentable over Li et al. US 2018/0076723 (hereinafter Li) in view of Cittanti et al. High-Performance Digital Multiloop Control of LLC Resonant Converters for EV Fast Charging With LUT-Based Feedforward and Adaptive Gain (hereinafter Cittanti).
Regarding claims 1 and 8, Li discloses an on-board charger control system for an on-board charger (¶ 0033; the battery charger circuit 20) configured to charge an on-board battery (¶ 0032; for charging a battery) including a rectifier (¶ 0033; the first AC/DC stage/rectifier) and a CLLC resonant converter (¶ 0035; for DC/DC converters, whether it is resonant type (e.g., LLC, CLLC, SRC, etc.)) connected in series with the rectifier (see fig. 5; the AC/DC stage is connected in series with the DC/DC stage), wherein the on-board charger control system comprises:
a rectification control device (fig. 8, element 114; the control loops include a critical conduction mode (CRM) power factor correction (PFC) control loop 110 in ¶ 0050) configured to perform switching control on the rectifier (¶ 0053; The output of the CRM/PFC controller 114 of the control loop 110 is used to drive the switching transistors of the AC/DC stage of the converter circuit 50),
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so that an output voltage
V
d
c
the rectifier is near or equal to a desired output voltage
V
d
c
_
r
e
f
of the rectifier (¶ 0053; The control loop 120 is configured to regulate the
DC-link voltage between the AC/DC stage and the DC/DC stage in the converter circuit 50. To do so, the control loop 120 senses the voltage of the DC-link and the battery 102, and those voltages are used as reference inputs to the compensator 122 to regulate the input power);
a resonance control device configured to perform switching control on the CLLC resonant converter (¶ 0035, 0054; the compensator 134 in the control loop 130 is configured to sense the charging current, Ibat, of the battery 102 and develop a control signal to regulate the gain of the DC/DC stage through the VCO 136); and
an additional control device configured to:
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determine the desired output voltage
V
d
c
_
r
e
f
for the rectifier based on a battery voltage
V
d
c
_
o
u
t
(Claim 1: a control system comprising: an intermediate link voltage regulation control loop configured, in a first mode of operation, to regulate the intermediate link voltage (desired output voltage) through the first converter stage based on a voltage of the battery;), and
provide the determined desired output voltage
V
d
c
_
r
e
f
to the rectification control device (
V
D
C
-
L
i
n
k
voltage can track the charging voltage of the battery over a range from 250V to 420V; the intermediate link voltage in the proposed concepts can change over time according to the voltage of the battery 102 as it is being charged in ¶¶ 0044-0045);
determine a desired output current
I
d
c
_
o
u
t
_
r
e
f
for the CLLC resonant converter based on the battery voltage
V
d
c
_
o
u
t
(see fig. 9;
I
b
a
t
_
r
e
f
is based on
V
b
a
t
and
V
D
C
_
L
i
n
k
), and provide the determined desired output current
I
d
c
_
o
u
t
_
r
e
f
to the resonance control device (¶ 0054; The compensator 134 in the control loop 130 is configured to sense the charging current, Ibat, of the battery 102 and develop a control signal to regulate the gain of the DC/DC stage through the VCO 136. Therefore, the current); and
provide, to the resonance control device, a switching frequency f of the CLLC resonant converter (¶ 0054; the compensator 134 in the control loop 130 is configured to sense the charging current, Ibat, of the battery 102 and develop a control signal to regulate the gain of the DC/DC stage through the VCO 136 by changing the frequency), so that the resonance control device performs switching control on the CLLC resonant converter based on the switching frequency f of the CLLC resonant converter (¶¶ 0046, 0054; by changing the frequency).
Li fails to teach wherein the switching frequency f is determined based on a voltage gain M and a quality factor Q of the CLLC resonant converter.
However, Cittanti further discloses wherein the switching frequency f is determined based on a voltage gain M and a quality factor Q of the CLLC resonant converter (pages 6 and 10; Cittanti discloses the simplest way to extract the fsw (M,Q) LUT is by numerically inverting the FHA gain expression [18] as shown below).
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It would have been obvious to one skilled in the art before the effective filing date of the claimed invention to modify Li to incorporate with the teaching of Cittanti by calculating the switching frequency based on gain and quality factor, because it would be advantageous to accurately tune the current control loop performance and decrease the closed-loop stability margin.
Regarding claims 2 and 9, Li in view of Cittanti discloses the on-board charger control system wherein, the additional control device is further configured to:
determine the desired output voltage
V
d
c
_
r
e
f
for the rectifier based on the battery voltage
V
d
c
_
o
u
t
so that the voltage gain M of the CLLC resonant converter is less than 1 (Li, ¶ 0045 and fig. 3A; the DC-Link voltage can track the charging voltage of the battery 102 over a range from 250V to 420V. Over that range, the gain the DC/DC stage can be substantially maintained at a constant value of about 1 [the constant value could be less than 1]. For example, when the gain is 0.71, and the corresponding voltage is 250V); and
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determine the desired output current
I
d
c
_
o
u
t
_
r
e
f
for the CLLC resonant converter based on the battery voltage
V
d
c
_
o
u
t
(Li, ¶ 0054; the compensator 134 in the control loop 130 is configured to sense the charging current, Ibat, of the battery 102 and develop a control signal to regulate the gain of the DC/DC stage through the VCO 136 by changing the frequency. Furthermore, the charging current, Ibat, of the battery is based on the gain of the DC/DC stage), to determine the quality factor Q of the CLLC resonant converter (Cittanti, page 12: Quality factor Q can be obtained with FHA),
wherein the switching frequency f of the CLLC resonant converter determined based on the voltage gain M and quality factor Q of the CLLC resonant converter is greater than or equal to a resonant frequency f1 of the CLLC resonant converter and wherein the resonant frequency f1 is based on an inductance and capacitance on a primary side of a fundamental wave equivalent circuit of the CLLC resonant converter (Cittanti, pages 6 and 10; Cittanti discloses the simplest way to extract the fsw(M,Q) LUT is by numerically inverting the FHA gain expression [18]; The
L
e
q
variation is illustrated in Fig. 6 as a function of the normalized switching frequency fsw/fr and the inductance ratio λ).
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Regarding claim 3, Li fails to disclose wherein the additional control device further comprises: a storage device for storing a correspondence of the voltage gain M, the quality factor Q to a per-unit switching frequency fn of the CLLC resonant converter, wherein the per-unit switching frequency fn is a ratio of the switching frequency to the resonant frequency fi; and a frequency determining device configured to determine, based on the correspondence stored in the storage device, the switching frequency f of the CLLC resonant converter corresponding to the determined voltage gain M and quality factor Q of the CLLC resonant converter.
However, Cittanti discloses wherein the additional control device further comprises:
a storage device for storing a correspondence of the voltage gain M (pages 9-10; the LUT inherently stores the information regarding ∂M/∂fsw and ∂Q/∂fsw, which can be exploited for the controller gain adaptation in (26) and (27) in place of the
analytical FHA expressions (20) and (21)…The steady-state fsw values,
obtained as function of the operating voltage gain M and quality factor Q, are stored in an LUT, and the desired feedforward value is extracted from the LUT by linear interpolation),
the quality factor Q to a per-unit switching frequency fn of the CLLC resonant converter, wherein the per-unit switching frequency fn is a ratio of the switching frequency to the resonant frequency fi (Cittanti, pages 6 and 10; Cittanti discloses the simplest way to extract the fsw(M,Q) LUT is by numerically inverting the FHA gain expression [18]); and
a frequency determining device configured to determine, based on the correspondence stored in the storage device, the switching frequency f of the CLLC resonant converter corresponding to the determined voltage gain M and quality factor Q of the CLLC resonant converter (page 10; the exploitation of M and Q allows us to normalize the converter operating conditions and uniquely identify a working point
in the inductive region (i.e., the stable region) with only two parameters, thus requiring a simple 2-D LUT).
It would have been obvious to one skilled in the art before the effective filing date of the claimed invention to modify Li to incorporate with the teaching of Cittanti by including a look-up table (LUT) in the system, because it would be advantageous to increase overall accuracy with respect to each operating mode and further optimize battery charging process.
Regarding claims 4 and 11, Li in view of Cittanti further discloses wherein the resonance control device is further configured to:
perform switching control on the CLLC resonant converter at the switching frequency f of the CLLC resonant converter (¶ 0054; the compensator 134 in the control loop 130 is configured to sense the charging current, Ibat, of the battery 102 and develop a control signal to regulate the gain of the DC/DC stage through the VCO 136 by changing the frequency);
acquire an output current Id_out of the CLLC resonant converter (¶ 0054; the control loop 130 is configured to sense the charging current, Ibat, of the battery
102);
adjust, in response to a difference DIFF between the acquired output current Id_out of the CLLC resonant converter and the desired output current Id_outref of the CLLC resonant converter being greater than a pre-determined threshold TDIFF (see fig. 8; difference between Ibat and Ibat_ref), the switching frequency f of the CLLC resonant converter to an adjusted switching frequency fa (¶ 0054; The SOTC 132 of the control loop 130 is configured to control certain transient, startup, and burst conditions for the converter circuit 50 based on the current reference Ibat) by:
searching the storage device for the stored correspondence of the voltage gain M, the quality factor Q to the per-unit switching frequency fn of the CLLC resonant converter, to determine a possible value for the adjusted switching frequency fa, or
increasing or decreasing, heuristically one or more times, the switching frequency f applied to the CLLC resonant converter in a vicinity of the switching frequency f of the CLLC resonant converter based on the difference DIFF (see fig. 8; difference between Ibat and Ibat_ref), until the difference DIFF is less than the threshold TDIFF (¶ 0054; develop a control signal to regulate the gain of the DC/DC stage through the VCO 136 by changing the frequency); and
perform switching control on the CLLC resonant converter at the adjusted switching frequency fa (¶ 0054; by changing the frequency).
Regarding claim 7, Li further discloses an on-board charger system, comprising: an on-board charger (Fig. 8: AC/DC stage and DC/DC stage) comprising a rectifier (fig. 8, element AC/DC stage) and a CLLC resonant converter (¶ 0035; DC/DC converters and it is resonant type (e.g., LLC, CLLC, SRC, etc.)) connected in series with the rectifier (see fig. 8); and the on-board charger control system of claim 1, wherein the on-board charger control system (see fig. 8, element 114) is coupled to the on-board charger.
Regarding claim 10, Li in view of Cittanti discloses the on-board charger control method further comprising:
determining, based on a pre-stored correspondence of the voltage gain M (Cittanti, pages 9-10; the steady-state fsw values, obtained as function of the operating voltage gain M and quality factor Q, are stored in an LUT), the quality factor Q to a per-unit switching frequency fn of the CLLC resonant converter (Cittanti, pages 6 and 10; Cittanti discloses the simplest way to extract the fsw (M,Q) LUT is by numerically inverting the FHA gain expression [18]), the switching frequency f of the CLLC resonant converter corresponding to the determined voltage gain M and quality factor Q of the CLLC resonant converter (Cittanti, pages 6 and 10; Cittanti discloses the simplest way to extract the fsw (M,Q) LUT is by numerically inverting the FHA gain expression [18] as shown above).
Allowable Subject Matter
Claims 5-6, 12 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.
The following is a statement of reasons for the indication of allowable subject matter:
Regarding claims 5 and 12, Li further discloses wherein the battery voltage Vdc_out has a desired voltage range in operation, the desired voltage range being [Vmin, Vmax] (¶ 0032; from 250V to 400V and see fig. 3A above). However, the prior art fails to teach or suggest further inclusion of the additional control device is further configured to: determine the desired output voltage Vdc_ref to be Vmin, and the desired output current Idc_out_ref to be (Pmax/Vdc_out)*k1, if the battery voltage Vdc_out satisfies (Vdc_out*N+Vcompen)≤Vmin, determine the desired output voltage Vdc_ref to be (Vdc_out*N+Vcompen) and the desired output current Idc_out_ref to be (Pmax/Vdc_out), if the battery voltage Vdc_out satisfies Vmin < (Vdc_out*N+Vcompen) ≤Vmax, or determine the desired output voltage Vdc_ref to be Vmax, and the desired output current Idc_out_ref to be (Pmax/Vdc_out)*k2, if the battery voltage Vdc_out satisfies (Vdc_out*N+Vcompen)>Vmax, wherein N refers to a voltage ratio of a primary side voltage to a secondary side voltage of a transformer in the CLLC resonant converter, Vcompen refers to an empirical compensation value associated with the desired voltage range and harmonic factors of the CLLC resonant converter, Pmax refers to a specified value of a maximum power given by a vehicle control unit (VCU) according to conditions of the on-board battery, and k1 and k2 refer to predetermined design derating factors and are both less than 1.
Conclusion
Any inquiry concerning this communication or earlier communications from the examiner should be directed to ZIXUAN ZHOU whose telephone number is (571)272-6739. The examiner can normally be reached 9:00 am to 5:00 pm.
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If attempts to reach the examiner by telephone are unsuccessful, the examiner’s supervisor, Julian Huffman can be reached at (571) 272-2147. The fax phone number for the organization where this application or proceeding is assigned is 571-273-8300.
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/ZIXUAN ZHOU/Primary Examiner, Art Unit 2859 09/24/2026
