CN112217381B - Single-phase converter direct-current bus voltage secondary ripple suppression circuit and method - Google Patents

Single-phase converter direct-current bus voltage secondary ripple suppression circuit and method Download PDF

Info

Publication number
CN112217381B
CN112217381B CN202010980927.1A CN202010980927A CN112217381B CN 112217381 B CN112217381 B CN 112217381B CN 202010980927 A CN202010980927 A CN 202010980927A CN 112217381 B CN112217381 B CN 112217381B
Authority
CN
China
Prior art keywords
voltage
controller
current
filter capacitor
filter
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Active
Application number
CN202010980927.1A
Other languages
Chinese (zh)
Other versions
CN112217381A (en
Inventor
刘普
梁燕
申永鹏
杨小亮
王延峰
赵俊
刘胜
胡四全
甘江华
刘刚
石伟
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Xi'an Yuneng Power Equipment Co ltd
Original Assignee
Zhengzhou University of Light Industry
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Zhengzhou University of Light Industry filed Critical Zhengzhou University of Light Industry
Priority to CN202010980927.1A priority Critical patent/CN112217381B/en
Publication of CN112217381A publication Critical patent/CN112217381A/en
Application granted granted Critical
Publication of CN112217381B publication Critical patent/CN112217381B/en
Active legal-status Critical Current
Anticipated expiration legal-status Critical

Links

Images

Classifications

    • HELECTRICITY
    • H02GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02MAPPARATUS FOR CONVERSION BETWEEN AC AND AC, BETWEEN AC AND DC, OR BETWEEN DC AND DC, AND FOR USE WITH MAINS OR SIMILAR POWER SUPPLY SYSTEMS; CONVERSION OF DC OR AC INPUT POWER INTO SURGE OUTPUT POWER; CONTROL OR REGULATION THEREOF
    • H02M1/00Details of apparatus for conversion
    • H02M1/14Arrangements for reducing ripples from dc input or output
    • H02M1/15Arrangements for reducing ripples from dc input or output using active elements

Abstract

The invention discloses a circuit and a method for inhibiting secondary ripples of direct-current bus voltage of a single-phase converter, which are an optimized Active Power Filter (APF) circuit and a method.A secondary harmonic auxiliary absorption circuit is built on the converter and comprises two power switching devices, a switching device control unit, a filter inductor and a filter capacitor, wherein the switching device control unit comprises a sampling circuit, a conditioning circuit, a calculation circuit and a voltage control circuit.

Description

Single-phase converter direct-current bus voltage secondary ripple suppression circuit and method
Technical Field
The invention belongs to the technical field of converter control, and particularly relates to a secondary ripple suppression circuit and a secondary ripple suppression method for a direct-current bus voltage of a single-phase converter.
Background
The existing methods for inhibiting double-frequency fluctuation of a direct-current bus of a single-phase converter are divided into a passive filtering method and an active filtering (APF) method, and three major categories of low-order harmonic of grid-connected current caused by voltage fluctuation of the direct-current bus are inhibited through a control strategy. The traditional passive filtering method directly connects a large capacitor or an LC resonance circuit in parallel at two ends of a direct current bus to inhibit direct current voltage pulsation, and the method needs very large capacitors and inductance values, so that the whole equipment has large volume, low power density and high manufacturing cost; the active filtering (APF) method is mainly characterized in that two or more fully-controlled power devices are added on the basis of the original single-phase PWM circuit, the complexity of the system is increased, the method needs to be further optimized, the cost is reduced, and the performance and the system stability are improved.
Disclosure of Invention
Aiming at the problem of secondary component fluctuation of the direct current power of the single-phase converter, the invention provides a secondary ripple suppression method of the direct current bus voltage of the single-phase converter, which is based on the establishment of a secondary harmonic auxiliary absorption circuit and comprises a first power switch device, a second power switch device, a control unit, a filter inductor and a filter capacitor, wherein the filter inductor is connected with the filter capacitor in parallel with the second power switch device, and the method is characterized by comprising the following steps:
step 1: voltage U to filter inductanceL2And current I of filter inductorL2Sampling, conditioning and transmitting to a control unit;
step 2: calculating and controlling the terminal voltage of the filter capacitor;
and step 3: outputting a PWM control signal by using the terminal voltage of the filter capacitor, the sampling voltage value of the filter capacitor and the sampling current value of the filter capacitor calculated in the step 2, and controlling a first power switch device and a second power switch device in the harmonic auxiliary absorption loop;
wherein the step 2 further comprises the following steps:
step 201: collecting AC voltage UsAnd calculating the phase angle w;
step 202: setting proper filter capacitor voltage direct-current component instruction value Uc-dc
Step 203: calculating the effective values of the alternating input voltage and the current of the converter;
step 204: according to the AC voltage phase angle w, the preset DC component U of the filter capacitor voltagec-dcInstruction value and Irms、UrmsSolving the double frequency component U in the filter capacitor terminal voltagec-2nd
Figure GDA0003242647130000021
Wherein and Irms、UrmsAre respectively a crossEffective values of instantaneous values of the current and alternating voltage;
the terminal voltage expression of the filter capacitor in the secondary harmonic auxiliary absorption circuit is as follows:
Figure GDA0003242647130000022
and step 3: design C2Voltage controller to realize UcAnd (5) controlling.
Step 301: the U calculated in step 204cTheoretical calculation value as U for system controlc2Command value U of voltagec2_refWill U isc2The difference is made between the instruction value and the actual sampling value;
step 302: will Uc2The difference between the instruction value and the actual sampling value is used as the input of the first PI controller and the first PR controller, and the sum of the output of the first PI controller and the output of the second PR controller is used as a capacitance current instruction Ic2_ref
Step 303: the capacitor current is commanded toc2_refAnd the actual capacitance current Ic2Taking the difference as the input of a second PI controller and a second PR controller, and summing the output of the second PI controller and the output of the second PR controller;
step 304: and the sum of the outputs of the second PI controller and the second PR controller is used as a modulation wave generated by the PWM pulse to finally generate the PWM pulse, and a first power switch device and a second power switch device in the second harmonic auxiliary absorption circuit are controlled.
The invention also relates to a single-phase converter direct-current bus voltage secondary ripple suppression circuit, which comprises a secondary harmonic auxiliary absorption circuit, a first power switch device, a second power switch device, a control unit, a filter inductor and a filter capacitor, wherein the first power switch device and the second power switch device are respectively connected with the first power switch device and the second power switch device; the first power switch device is connected with the second power switch device in series, the other end of the first power switch device is connected with one end of the direct-current bus capacitor, the other end of the direct-current bus capacitor is connected with the other end of the second power switch device in series, and the filter inductor is connected with the filter capacitor in parallel after being connected with the second power switch device in series.
Further, the control unit comprises a first PI controller, a second PI controller, a first PR controller, a second PR controller, and a PWM generation module, wherein the first PI controller and the first PR controller are connected in parallel to form a first parallel circuit, the second PI controller and the second PR controller are connected in parallel to form a second parallel circuit, the first parallel circuit and the second parallel circuit are connected in series, the second parallel circuit is connected with the PWM generation module, and the PWM generation module is configured to generate PWM pulses for controlling the first power tube and the second power tube.
The invention realizes the following technical effects:
1. the invention can effectively inhibit the double frequency fluctuation of the DC bus voltage of the converter;
2. the invention only adds two power devices, one filter inductor and one filter capacitor, and has simple structure, simple system control method and easy engineering application compared with the traditional active filter circuit.
Drawings
FIG. 1 is a typical H-bridge PWM converter circuit;
fig. 2 is a prior art secondary ripple rejection circuit;
FIG. 3 illustrates a single-phase PWM converter and a double-frequency ripple suppression circuit thereof according to the present invention;
FIG. 4 is a block diagram of the converter double frequency ripple rejection control of the present invention;
fig. 5 shows a totem-pole converter and a circuit diagram for suppressing double frequency ripple of the totem-pole converter.
Detailed Description
The invention will be described in further detail below with reference to the following figures and specific examples:
fig. 1 shows a typical H-bridge PWM rectifier circuit in the prior art. When the voltage and current on the alternating current side of the single-phase converter fluctuate sinusoidally at the same frequency, secondary pulsating power with the same magnitude as the system power is generated, and the secondary pulsating power appears as a secondary voltage ripple on the direct current side. The sine variation expression of the alternating-current side voltage and current is as follows:
when the converter operates under an ideal unit power factor, the frequency of the switching tube is far greater than the frequency of a power grid, the loss and the on-off time of the switching tube are ignored, and the voltage and waveform expressions are assumed as follows:
Figure GDA0003242647130000041
in the formula of Urms,IrmsIs us,isEffective value of us,isFor ac voltage-current instantaneous value
The energy stored on the ac inductor is represented as:
Figure GDA0003242647130000042
the derivation yields the power on the inductor as:
PL=-LIrms 2sin (2 ω t) (type 3)
Due to the instantaneous total power balance, the dc side instantaneous power can be expressed as:
Figure GDA0003242647130000043
from the above formula, when the single-phase converter operates at unity power factor, the dc power thereof consists of a dc component and a frequency-doubled component. The second harmonic component will reduce device lifetime and additionally cause low order harmonics in the ac current. Therefore, a suitable algorithm and topology need to be constructed to solve the problem.
The existing methods for secondary ripples of a direct-current bus of a single-phase converter are roughly classified into a passive filtering method and an active filtering (APF) method, and an energy storage element for compensating secondary ripple power can be a capacitor or an inductor.
FIG. 2 shows a prior art topology-secondary ripple rejection circuit of an active filter with two fully-controlled switch transistors S5And S6And two diodes D1And D2The circuit absorbing and compensating the converter input by an inductor as an energy storage elementSecondary pulsating power. In the circuit, the current in the inductor can only flow in a single direction, the magnetic core loss is large, the inductor current can sharply rise at the minimum value of the inductor current in the circuit, the value of the energy storage inductor cannot be too large in order to ensure that the inductor current has a large enough change rate to track the command current of the inductor current, but the value of the inductor cannot be too small, the amplitude of the inductor current can be increased due to the too small inductor current, the ripple of the inductor current can also be increased, and the current stress of the switching tube can also be large.
In order to solve the above problems, the present invention provides a circuit and a method for suppressing the second ripple of the dc bus voltage of a single-phase converter, as shown in fig. 3, a second harmonic auxiliary absorption circuit is built on the existing converter, and the absorption circuit includes a first power switch device S5And a second power switch device S6A control unit, a filter inductor L2A filter capacitor C2
Wherein the first power switch device S5And a second power switch device S6Series, first power switching device S5The other end of the capacitor (C) and a DC bus capacitor (C)1Is connected to a DC bus capacitor C1And the other end of the first power switch device S6The other end of the series connection is connected with a filter inductor L2And a filter capacitor C2Connected in series with a second power switch device S6And (4) connecting in parallel.
The invention applies a Proportional Integral (PI) controller, because the PI regulator can not realize zero error tracking of an alternating current signal, and also applies a Proportional Resonance (PR) controller, and the system is controlled according to the proportion P and the resonance R of a feedback signal and a given deviation. Since the PR regulator has infinite gain at the corresponding resonance point, the dc-side voltage can be made to have no steady-state error with respect to a given voltage at the corresponding frequency.
Furthermore, the method for inhibiting the secondary ripple of the direct current bus voltage of the single-phase converter provided by the invention is characterized in that the filtering inductance voltage U in the circuit is filtered by building a sampling circuit for controlling a secondary harmonic auxiliary absorption circuitL2And filtering the inductor current IL2After sampling and conditioning, transmitting to controlA machine;
collecting AC voltage UsAnd calculating the phase angle w;
set the appropriate Uc-dcAn instruction value;
calculating the effective values of the alternating input voltage and the current of the converter;
according to the phase angle w of the AC voltage, preset C2Voltage dc component Uc-dcInstruction value and Irms、UrmsSolving for C2Double frequency component U in end voltagec-2nd
Figure GDA0003242647130000061
In auxiliary circuit C2The end pressure expression of (1) is as follows:
Figure GDA0003242647130000062
u calculated in the above formulacTheoretical calculation value as U for system controlc2Command value U of voltagec2_refWill U isc2The difference is taken as the input of the first PI controller and the first PR controller, and the sum of the output of the first PI controller and the output of the first PR controller is taken as a capacitance current instruction Ic2_refThe composite controller is constructed to realize the outer loop control function of the auxiliary loop voltage, wherein the direct current component in the first PI controller control instruction and the alternating current component in the first PR controller control instruction;
the capacitor current is commanded toc2_refAnd the actual capacitance current Ic2After difference is made, the difference is used as the input of a second PI controller and a second PR controller, the sum of the outputs of the second PI controller and the second PR controller is used as a modulation wave generated by a PWM pulse to finally generate the PWM pulse, and a first power switching device and a second power switching device in a secondary harmonic auxiliary absorption circuit are controlled to realize UcAnd (5) controlling.
The invention also relates to a single-phase converter direct-current bus voltage secondary ripple suppression circuit which comprises a secondary harmonic auxiliary absorption circuit, specifically comprises a first power switch device, a second power switch device, a control unit, a filter inductor and a filter capacitor.
Further, the control unit comprises a first PI controller, a second PI controller, a first PR controller, a second PR controller, and a PWM generation module, wherein the first PI controller and the first PR controller are connected in parallel to form a first parallel circuit, the second PI controller and the second PR controller are connected in parallel to form a second parallel circuit, the first parallel circuit and the second parallel circuit are connected in series, the second parallel circuit is connected with the PWM generation module, and the PWM generation module is configured to generate PWM pulses for controlling the first power tube and the second power tube.
To make the DC bus capacitor c1The upper voltage is stable without double frequency fluctuation, i.e. double frequency power, so that the auxiliary L of the structure2C2The loop absorbs double frequency power input by the alternating current side. When C is present2Voltage at both ends is Uc-dc+Uc-2ndWhen the current includes DC component and two frequency multiplication component, the current only contains two frequency multiplication component, so that the inductor L2On the filter capacitor C with quadruple frequency power2The upper current is the quadruple frequency power and the double frequency power. By setting appropriate filter capacitors C2The voltage value at both ends can ensure the filter capacitor C2And a filter inductor L2The quadruple frequency component is very small, and the harmonic requirement of the system is met.
The circuit and the method for suppressing the secondary ripple of the direct-current bus voltage of the single-phase converter are also applicable to single-phase converters with other topologies, such as totem-pole topology, and as shown in fig. 5, the circuit and the method for suppressing the secondary ripple of the direct-current bus voltage are applied to a circuit diagram of the totem-pole converter. The design of the DC bus voltage secondary ripple suppression controller is shown in FIG. 4.
Finally, it should be noted that the above-mentioned embodiments are only used for illustrating the technical solutions of the present invention and not for limiting the same, and those skilled in the art who read the present application can make various modifications or alterations of the present invention by referring to the above-mentioned embodiments within the scope of the claims of the present application.

Claims (1)

1. The utility model provides a single-phase converter direct current busbar voltage secondary ripple suppression method, based on setting up the supplementary absorption circuit of second harmonic, including first power switching device and second power switching device, a control unit, a filter inductance, a filter capacitance, wherein first power switching device and second power switching device are established ties, the other end of first power switching device is connected with the one end of direct current busbar capacitance, the other end of direct current busbar capacitance is connected with the other end that second power switching device establishes ties, filter inductance and filter capacitance establish ties the back and connect in parallel with second power switching device, its characterized in that, including following step:
step 1: voltage U to filter inductanceL2And current I of filter inductorL2Sampling, conditioning and transmitting to a control unit;
step 2: calculating and controlling the terminal voltage of the filter capacitor;
and step 3: outputting a PWM control signal by using the terminal voltage of the filter capacitor, the sampling voltage value of the filter capacitor and the sampling current value of the filter capacitor calculated in the step 2, and controlling a first power switch device and a second power switch device in the harmonic auxiliary absorption loop;
wherein the step 2 further comprises the following steps:
step 201: collecting AC voltage UsAnd calculating the phase angle w;
step 202: setting proper filter capacitor voltage direct-current component instruction value Uc-dc
Step 203: calculating the effective values of the alternating input voltage and the current of the converter;
step 204: according to the AC voltage phase angle w, the preset DC component U of the filter capacitor voltagec-dcInstruction value and Irms、UrmsSolving the double frequency component U in the filter capacitor terminal voltagec-2nd
Figure FDA0003452203160000011
Wherein and Irms、UrmsEffective values of instantaneous values of the alternating current and the alternating voltage respectively; c2Is the filter capacitor, L1Is an alternating current side inductor;
the terminal voltage expression of the filter capacitor in the secondary harmonic auxiliary absorption circuit is as follows:
Figure FDA0003452203160000012
wherein the step 3 further comprises the following steps:
step 301: the U calculated in step 204cThe theoretical calculation value is used as an instruction value for controlling the terminal voltage of the filter capacitor by the system, and the instruction value of the terminal voltage of the filter capacitor is subtracted from the actual sampling value;
step 302: filtering capacitor voltage Uc2The difference between the instruction value and the actual sampling value is used as the input of a first PI controller and a first PR controller, and the sum of the output of the first PI controller and the output of the first PR controller is used as a capacitance current instruction;
step 303: taking the difference between the current instruction of the filter capacitor and the actual capacitor current as the input of a second PI controller and a second PR controller, and taking the sum of the output of the second PI controller and the output of the second PR controller;
step 304: and the sum of the outputs of the second PI controller and the second PR controller is used as a modulation wave generated by the PWM pulse to finally generate the PWM pulse, and a first power switch device and a second power switch device in the second harmonic auxiliary absorption circuit are controlled.
CN202010980927.1A 2020-09-17 2020-09-17 Single-phase converter direct-current bus voltage secondary ripple suppression circuit and method Active CN112217381B (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN202010980927.1A CN112217381B (en) 2020-09-17 2020-09-17 Single-phase converter direct-current bus voltage secondary ripple suppression circuit and method

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN202010980927.1A CN112217381B (en) 2020-09-17 2020-09-17 Single-phase converter direct-current bus voltage secondary ripple suppression circuit and method

Publications (2)

Publication Number Publication Date
CN112217381A CN112217381A (en) 2021-01-12
CN112217381B true CN112217381B (en) 2022-03-01

Family

ID=74049536

Family Applications (1)

Application Number Title Priority Date Filing Date
CN202010980927.1A Active CN112217381B (en) 2020-09-17 2020-09-17 Single-phase converter direct-current bus voltage secondary ripple suppression circuit and method

Country Status (1)

Country Link
CN (1) CN112217381B (en)

Families Citing this family (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN113098421A (en) * 2021-04-01 2021-07-09 中国矿业大学 Method for suppressing low-frequency ripple of direct-current side voltage of parallel active power filter
CN113726199B (en) * 2021-09-03 2023-09-22 安徽工业大学 Low-output ripple boost rectifier and control method thereof

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN103746550A (en) * 2013-12-24 2014-04-23 青海能高新能源有限公司 Harmonic suppression method applied to grid-connected photovoltaic inverter
CN106411161A (en) * 2016-08-06 2017-02-15 太原理工大学 Three-phase PWM converter in voltage unbalance condition and optimal control method of three-phase PWM converter
CN207603216U (en) * 2017-11-28 2018-07-10 嘉兴伏尔电子科技有限公司 A kind of more proportional integration resonant controllers
CN109067154A (en) * 2018-08-31 2018-12-21 北京交通大学 A kind of active filter and the method for eliminating train DC bus secondary resonance
CN110829563A (en) * 2019-10-22 2020-02-21 合肥巨一动力系统有限公司 Proportion resonance control-based secondary harmonic suppression method for multiplexing charger

Family Cites Families (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP2313966B1 (en) * 2008-07-30 2019-07-03 Rolls-Royce Corporation Electrical power system with high-density pulse width modulated (pwm) rectifier
JP5332621B2 (en) * 2009-01-07 2013-11-06 富士電機株式会社 Uninterruptible power system
CN103023360B (en) * 2012-07-03 2014-11-05 中南大学 Single-phase alternating current (AC)/ direct current (DC) converter with secondary fluctuating power decoupling and control method thereof
JP2015053833A (en) * 2013-09-09 2015-03-19 ローム株式会社 Dc/dc converter and its control circuit, and electronic apparatus
CA2960663C (en) * 2014-09-12 2022-01-18 Queen's University At Kingston High-power single-stage led driver with bipolar ripple cancellation
CN104836426B (en) * 2015-06-08 2017-08-29 南京航空航天大学 A kind of second harmonic current compensator and its control method
CN105429448B (en) * 2015-11-11 2018-10-02 阳光电源股份有限公司 A kind of single-phase inverter and its DC bus Ripple Suppression method

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN103746550A (en) * 2013-12-24 2014-04-23 青海能高新能源有限公司 Harmonic suppression method applied to grid-connected photovoltaic inverter
CN106411161A (en) * 2016-08-06 2017-02-15 太原理工大学 Three-phase PWM converter in voltage unbalance condition and optimal control method of three-phase PWM converter
CN207603216U (en) * 2017-11-28 2018-07-10 嘉兴伏尔电子科技有限公司 A kind of more proportional integration resonant controllers
CN109067154A (en) * 2018-08-31 2018-12-21 北京交通大学 A kind of active filter and the method for eliminating train DC bus secondary resonance
CN110829563A (en) * 2019-10-22 2020-02-21 合肥巨一动力系统有限公司 Proportion resonance control-based secondary harmonic suppression method for multiplexing charger

Also Published As

Publication number Publication date
CN112217381A (en) 2021-01-12

Similar Documents

Publication Publication Date Title
US11621651B2 (en) High-power density, single-phase cascaded H-bridge rectifier, control method, and control system
CN111064359A (en) Wide-range bidirectional conversion circuit and control method
CN112165267B (en) High-transformation-ratio bidirectional AC/DC converter, control method thereof and pre-charging method thereof
CN111245010B (en) Double closed-loop control method based on LLCL type three-phase grid-connected inverter
CN112234808B (en) Double-frequency ripple suppression circuit and suppression method of single-phase inverter
CN112217381B (en) Single-phase converter direct-current bus voltage secondary ripple suppression circuit and method
CN111953218B (en) Active power decoupling control method and controller for cascaded H-bridge rectifier and rectifier
Li et al. Active DC-link power filter for single phase PWM rectifiers
CN111740455A (en) Bus interface converter control method for uniformly compensating alternating-current unbalanced voltage and direct-current pulsating voltage
Sosa et al. Comparative evaluation of L and LCL filters in transformerless grid tied converters for active power injection
Lee et al. Design methodology of passive damped LCL filter using current controller for grid-connected three-phase voltage-source inverters
Chaudhary et al. Front-end buck rectifier with reduced filter size and single-loop control
WO2024016749A1 (en) Flexible dc-to-dc converter capable of multi-port dc power flow control and control method thereof
CN102769291A (en) Active power filter based on multiphase converter structure
CN103929084A (en) Modular multilevel converter low-frequency control method based on resonant filter circuit
CN113904570A (en) Three-phase controllable pulse power supply rectifier topology and rectification method
Arulkumar et al. Design of optimal LLCL filter with an improved control strategy for single phase grid connected PV inverter
CN116073356A (en) Secondary harmonic current suppression method for bipolar direct current system
CN112117925B (en) DCM single-bridge-arm integrated split-source inverter control method for photovoltaic grid-connected occasions
CN115242065A (en) Topology for reducing uncontrolled rectified voltage ripple and control method thereof
CN113114033A (en) Direct-current-side secondary ripple suppression device for traction transmission system and control method
Terada et al. Control of a three-phase grid-tied inverter designed for discontinuous current mode operation
Yang et al. Modelling and Controller Design for Three-Phase Four-Leg Three-Level T-Type Inverter
Pho et al. Discrete-Time Quasi Sliding Mode Control of Single-phase T-type Inverters for Residential PV Applications
Li et al. A selective order voltage ripple suppression control strategy for DC-DC converter

Legal Events

Date Code Title Description
PB01 Publication
PB01 Publication
SE01 Entry into force of request for substantive examination
SE01 Entry into force of request for substantive examination
GR01 Patent grant
GR01 Patent grant
TR01 Transfer of patent right

Effective date of registration: 20240318

Address after: Room B4, 9 / F, Cuiting building, No.1, middle section of Xingqing Road, Beilin District, Xi'an, Shaanxi 710000

Patentee after: Xi'an Yuneng Power Equipment Co.,Ltd.

Country or region after: China

Address before: No.5 Dongfeng Road, Jinshui District, Zhengzhou City, Henan Province

Patentee before: Zhengzhou University of light industry

Country or region before: China

TR01 Transfer of patent right