CN103595262A - Frequency adjusting circuit for wireless charging system - Google Patents

Frequency adjusting circuit for wireless charging system Download PDF

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Publication number
CN103595262A
CN103595262A CN201310536884.8A CN201310536884A CN103595262A CN 103595262 A CN103595262 A CN 103595262A CN 201310536884 A CN201310536884 A CN 201310536884A CN 103595262 A CN103595262 A CN 103595262A
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CN
China
Prior art keywords
frequency
circuit
resonant
capacitance
controller
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Pending
Application number
CN201310536884.8A
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Chinese (zh)
Inventor
孙跃
王智慧
崔金泽
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JIANGSU KEYIDA MACHINE CO Ltd
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JIANGSU KEYIDA MACHINE CO Ltd
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Priority to CN201310536884.8A priority Critical patent/CN103595262A/en
Publication of CN103595262A publication Critical patent/CN103595262A/en
Pending legal-status Critical Current

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    • HELECTRICITY
    • H02GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02JCIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY
    • H02J50/00Circuit arrangements or systems for wireless supply or distribution of electric power
    • H02J50/10Circuit arrangements or systems for wireless supply or distribution of electric power using inductive coupling
    • H02J50/12Circuit arrangements or systems for wireless supply or distribution of electric power using inductive coupling of the resonant type
    • 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
    • H02M3/00Conversion of dc power input into dc power output
    • H02M3/01Resonant DC/DC converters
    • H02M3/015Resonant DC/DC converters with means for adaptation of resonance frequency, e.g. by modification of capacitance or inductance of resonance circuit
    • 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
    • H02M7/00Conversion of ac power input into dc power output; Conversion of dc power input into ac power output
    • H02M7/42Conversion of dc power input into ac power output without possibility of reversal
    • H02M7/44Conversion of dc power input into ac power output without possibility of reversal by static converters
    • H02M7/48Conversion of dc power input into ac power output without possibility of reversal by static converters using discharge tubes with control electrode or semiconductor devices with control electrode
    • H02M7/4815Resonant converters
    • H02M7/4818Resonant converters with means for adaptation of resonance frequency, e.g. by modification of capacitance or inductance of resonance circuits
    • 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
    • H02M7/00Conversion of ac power input into dc power output; Conversion of dc power input into ac power output
    • H02M7/42Conversion of dc power input into ac power output without possibility of reversal
    • H02M7/44Conversion of dc power input into ac power output without possibility of reversal by static converters
    • H02M7/48Conversion of dc power input into ac power output without possibility of reversal by static converters using discharge tubes with control electrode or semiconductor devices with control electrode
    • H02M7/53Conversion of dc power input into ac power output without possibility of reversal by static converters using discharge tubes with control electrode or semiconductor devices with control electrode using devices of a triode or transistor type requiring continuous application of a control signal
    • H02M7/537Conversion of dc power input into ac power output without possibility of reversal by static converters using discharge tubes with control electrode or semiconductor devices with control electrode using devices of a triode or transistor type requiring continuous application of a control signal using semiconductor devices only, e.g. single switched pulse inverters
    • H02M7/5387Conversion of dc power input into ac power output without possibility of reversal by static converters using discharge tubes with control electrode or semiconductor devices with control electrode using devices of a triode or transistor type requiring continuous application of a control signal using semiconductor devices only, e.g. single switched pulse inverters in a bridge configuration
    • H02M7/53871Conversion of dc power input into ac power output without possibility of reversal by static converters using discharge tubes with control electrode or semiconductor devices with control electrode using devices of a triode or transistor type requiring continuous application of a control signal using semiconductor devices only, e.g. single switched pulse inverters in a bridge configuration with automatic control of output voltage or current
    • 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
    • H02M3/00Conversion of dc power input into dc power output
    • H02M3/22Conversion of dc power input into dc power output with intermediate conversion into ac
    • H02M3/24Conversion of dc power input into dc power output with intermediate conversion into ac by static converters
    • H02M3/28Conversion of dc power input into dc power output with intermediate conversion into ac by static converters using discharge tubes with control electrode or semiconductor devices with control electrode to produce the intermediate ac
    • H02M3/325Conversion of dc power input into dc power output with intermediate conversion into ac by static converters using discharge tubes with control electrode or semiconductor devices with control electrode to produce the intermediate ac using devices of a triode or a transistor type requiring continuous application of a control signal
    • H02M3/335Conversion of dc power input into dc power output with intermediate conversion into ac by static converters using discharge tubes with control electrode or semiconductor devices with control electrode to produce the intermediate ac using devices of a triode or a transistor type requiring continuous application of a control signal using semiconductor devices only
    • H02M3/33569Conversion of dc power input into dc power output with intermediate conversion into ac by static converters using discharge tubes with control electrode or semiconductor devices with control electrode to produce the intermediate ac using devices of a triode or a transistor type requiring continuous application of a control signal using semiconductor devices only having several active switching elements
    • H02M3/33573Full-bridge at primary side of an isolation transformer
    • YGENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02BCLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO BUILDINGS, e.g. HOUSING, HOUSE APPLIANCES OR RELATED END-USER APPLICATIONS
    • Y02B70/00Technologies for an efficient end-user side electric power management and consumption
    • Y02B70/10Technologies improving the efficiency by using switched-mode power supplies [SMPS], i.e. efficient power electronics conversion e.g. power factor correction or reduction of losses in power supplies or efficient standby modes

Abstract

The invention discloses a frequency adjusting circuit for a wireless charging system. The frequency adjusting circuit comprises an inverter, a primary side resonance circuit, a secondary side resonance circuit and a power adjusting circuit, wherein the input end of the inverter is connected with a direct-current power supply, the output end of the power adjusting circuit is connected with a variable load, a frequency detector is connected to the primary side resonance circuit, the input end of the frequency detector is connected between the primary side resonance circuit and an excitation coil, the output end of the frequency detector can output a primary side resonance frequency value f1 to the first input end of a controller, the second input end of the controller is used for inputting a system set resonance frequency f0, the output control end of the controller is connected with a parallel-connection capacitor array, the parallel-connection capacitor array is in parallel connection to the primary side resonance capacitor, and the controller can control a capacitance value of the parallel-connection capacitor array according to the difference between the primary side resonance frequency value f1 and the secondary side resonance frequency value f0. The circuit is simple in structure, a control algorithm is easy to achieve, and the maximum system energy transfer is achieved.

Description

A kind of wireless charging system frequency adjustment circuit
Technical field
The invention belongs to charging circuit technical field, be specifically related to a kind of wireless charging system frequency adjustment circuit.
background method
As shown in Figure 1, contactless energy transmission system is mainly comprised of primary return and secondary loop.Wherein primary return is fixed, and mainly high-frequency inverter 1 and LC resonant circuit, consists of, and secondary loop is mainly by pick-up winding, compensating circuit, power conditioning circuitry 3 and variable load form, and can move within the specific limits, do not have electrical connection between primary return and secondary loop.Primary return mainly completes conversion and the transmission of electric energy, and secondary loop mainly completes picking up with power of energy and adjusts, and realizes the transmission of energy between system by space electromagnetic coupled.
Along with scientific and technical development, non-contact type energy transmission technology is used widely, non-contact power of the electric equipment of working such as the non-contact power of high-power electrical equipment, under the non-contact charge of low power portable electronic installation, particular surroundings etc.This technology is because of its contactless spark,, low noise good without device wearing and tearing, easy care, security performance, automaticity advantages of higher, thus have broad application prospects.
But owing to being subject to the impact of load variations and secondary loop displacement, the resonance frequency of system will change, particularly for load, switch, when load hour, system resonance frequency along with increase and increase rapidly; When increasing to a certain degree, resonance frequency tends towards stability; When increasing to infinity, be equivalent to load open circuit, now with resonance in a certain fixed frequency.Therefore, mechanism for picking in parallel can carry large resistance load under more stable frequency.But when load is excessive, the resonance of system shows as transmission reactive power, and efficiency of transmission is low, load cisco unity malfunction.
As shown in Figure 2, the relation curve of system through-put power and system resonance frequency is a parabola, system works frequency between time, through-put power is larger; At natural resonance frequency point place, get maximum.This frequency is the complete resonance frequency of picking up end, and its value is by determining.
Therefore, in contactless energy transmission system, usually need to adopt frequency stabilization control strategy.
Summary of the invention
Goal of the invention: for the deficiencies in the prior art, the object of the present invention is to provide a kind of wireless charging system frequency adjustment circuit, can guarantee the stability of primary return resonance frequency, realize the maximum power transfer of energy, meet user demand.
Technical scheme: in order to realize foregoing invention object, the technical solution adopted in the present invention is:
A frequency adjustment circuit, comprises inverter, former limit resonant circuit, and secondary resonant circuit, power conditioning circuitry, the input of described inverter is connected with DC power supply, and the output of described power conditioning circuitry is connected with variable load, on the resonant circuit of described former limit, be connected with frequency detector, the input of this frequency detector is connected between former limit resonant capacitance and excitation coil, the output of this frequency detector is exported former limit resonant frequency value f1 to the first input end of controller, the second input input system of this controller is set resonant frequency value f0, the output control terminal of described controller is connected with shunt capacitance array, this shunt capacitance array is connected in parallel on the resonant capacitance of described former limit, described controller is controlled the capacitance of described shunt capacitance array according to the difference of described former limit resonant frequency value f1 and secondary resonant frequency value f0.
In certain loading range, former limit resonant frequency value f1 increases with the increase of load RL.The actual operating frequency f1 of the resonance current detecting by frequency detector, utilize controller 4 by actual frequency f1 and pick up end natural frequency f0 and make comparisons, by gained difference, the break-make of control capacitance array switch, thereby effectively change capacitance size, when load RL increases, operating frequency f1 is greater than natural resonance frequency f0, while being △ f=f1-f0>0, by controller, control the suitable effective value that increases former limit resonant capacitance of shunt capacitance array to reduce operating frequency; When △ f=f1-f0<0, by controller, control effective value that shunt capacitance array suitably reduces former limit resonant capacitance to increase operating frequency, finally guarantee system stability and work in natural resonance frequency.
Described shunt capacitance array is by 9 0.1 nF, and the Capacitance parallel connection of 91 nF and 9 10 nF forms, and each capacitance series has a control switch, and the variable range of this shunt capacitance array is 0~99.9 nF.
By controller, control the on off operating mode of corresponding control switch, can realize shunt capacitance array effective capacitance value and change between 0~99.9 nF, adjusting step-length is 0.1nF.
Described former limit resonant circuit is tandem resonant tank, and described secondary resonant circuit is parallel resonant tank.
Under resonance frequency, when secondary loop adopts series resonance structure, secondary capacitance pressure drop and pick-up winding pressure drop offset, and system is voltage source to load output equivalent.While adopting parallel resonance structure, the electric current in inflow secondary capacitance and the idle component of the electric current in pick-up winding offset, and system is current source to load output equivalent.
And primary return, for series resonant circuit, when input voltage is square wave, series loop electric current is sinusoidal wave.Antiresonant circuit, when transmission of electricity stream is square wave, the both end voltage waveform of antiresonant circuit is sinusoidal wave.
For improving system power transmittability and efficiency, native system adopts soft switch series connection-parallel resonance pattern.
Beneficial effect: compared with prior art, remarkable advantage of the present invention comprises: circuit structure is simple, and control algolithm easily realizes, system has good dynamic responding speed, stability and anti-interference, in load variations process, can guarantee frequency stabilization, realize the transmission of system ceiling capacity.
Accompanying drawing explanation
Fig. 1 is the schematic block circuit diagram of contactless energy transmission system;
Fig. 2 is contactless energy transmission system power and frequency relation curve chart;
Fig. 3 is schematic block circuit diagram of the present invention;
Fig. 4 is the circuit theory diagrams of shunt capacitance array in Fig. 3.
Embodiment
Below in conjunction with accompanying drawing, the present invention is further described, it should be pointed out that the commonsense method personnel for this area, under the premise without departing from the principles of the invention, can also make some modification and improvement, and these also should be considered as belonging to protection scope of the present invention.
As Fig. 1, shown in Fig. 3, wireless charging system frequency adjustment circuit, comprises inverter 1, former limit resonant circuit L p, C p, secondary resonant circuit L s, C s, power conditioning circuitry 3; Inverter 1 is the first switching tube S 1, second switch pipe S 2, the 3rd switching tube S 3and the 4th switching tube S 4the bridge inverter main circuit forming, is connected with DC power supply Edc at the input of inverter 1.Former limit resonant circuit L p, C pby excitation coil L pwith former limit resonant capacitance C pthe tandem resonant tank forming, described secondary resonant circuit L s, C sby pick-up winding L swith secondary resonant capacitance C sthe parallel resonant tank forming, at excitation coil L pwith pick-up winding L sbetween produce magnetic Field Coupling, thereby realize former limit to the non-contact type energy transmission of secondary, at the output of power conditioning circuitry 3, be connected with variable load RL.
Former limit resonant circuit Lp, on Cp, be also connected with frequency detector 4, the input of this frequency detector 4 is connected between former limit resonant capacitance Cp and excitation coil Lp, the output of this frequency detector 4 is exported former limit resonant frequency value f1 to the first input end of controller 5, the second input of this controller 5 has also been inputted secondary resonant frequency value f0, the output control terminal of controller 5 is connected with shunt capacitance array 2, this shunt capacitance array 2 is connected in parallel on described former limit resonant capacitance Cp, controller 5 is controlled the capacitance of described shunt capacitance array 2 according to former limit resonant frequency value f1 and secondary resonant frequency value f0.
As shown in Figure 4, shunt capacitance array 2 is by 9 0.1 nF, the Capacitance parallel connection of 91 nF and 9 10 nF forms, be respectively C1-0.1nF~C9-0.1nF, C1-1nF~C9-1nF and C1-10nF~C9-10nF, each capacitance series has a control switch, be respectively K1-0.1nF~K9-0.1nF, K1-1nF~K9-1nF and K1-10nF~K9-10nF, by 27 switches, control respectively 27 electric capacity access states, this shunt capacitance array 2 is changed within the scope of 0~99.9 nF.
During such as the electric capacity of a 56.7nF of needs, by controller 4 turn on-switch K1-0.1nF~K7-0.1nF, K1-1nF~K6-1nF and K1-10nF~K5-10nF, the capacitance at shunt capacitance array 2 two ends is 56.7nF.
Operation principle of the present invention is: when load changes, cause resonance frequency f1 to change, the actual operating frequency f1 of the resonance current detecting by frequency detector 4, utilize controller 4 by actual frequency f1 and pick up end natural frequency f0 and make comparisons, by gained difference, the break-make of control capacitance array switch, thereby effectively change capacitance size, when load RL increases, operating frequency f1 is greater than natural resonance frequency f0, while being △ f=f1-f0>0, by controller, control the suitable effective value that increases former limit resonant capacitance of shunt capacitance array to reduce operating frequency, when △ f=f1-f0<0, by controller, control effective value that shunt capacitance array suitably reduces former limit resonant capacitance to increase operating frequency, finally guarantee system stability and work in natural resonance frequency.
Visible, circuit structure is simple, and control algolithm easily realizes, and system has good dynamic responding speed, stability and anti-interference, in load variations process, can guarantee frequency stabilization, realizes the transmission of system ceiling capacity.

Claims (3)

1. a wireless charging system frequency adjustment circuit, comprises inverter (1), former limit resonant circuit (L p, C p), secondary resonant circuit (L s, C s), power conditioning circuitry (3), the input of described inverter (1) is connected with DC power supply (Edc), the output of described power conditioning circuitry (3) is connected with variable load (RL), it is characterized in that: described former limit resonant circuit (Lp, Cp) on, be connected with frequency detector (4), the input of this frequency detector (4) is connected between former limit resonant capacitance (Cp) and excitation coil (Lp), the output of this frequency detector (4) is exported former limit resonant frequency value f1 to the first input end of controller (5), the second input input system of this controller (5) is set resonant frequency value f0, the output control terminal of described controller (5) is connected with shunt capacitance array (2), this shunt capacitance array (2) is connected in parallel on described former limit resonant capacitance (Cp), described controller (5) is controlled the capacitance of described shunt capacitance array (2) according to the difference of described former limit resonant frequency value f1 and secondary resonant frequency value f0.
2. a wireless charging system frequency adjustment circuit according to claim 1, it is characterized in that: described shunt capacitance array (2) is by 9 0.1 nF, the Capacitance parallel connection of 91 nF and 9 10 nF forms, each capacitance series has a control switch, and the variable range of this shunt capacitance array (2) effective capacitance value is 0~99.9 nF.
3. wireless charging system frequency adjustment circuit according to claim 1, is characterized in that: described former limit resonant circuit (L p, C p) be tandem resonant tank, described secondary resonant circuit (L s, C s) be parallel resonant tank.
CN201310536884.8A 2013-11-04 2013-11-04 Frequency adjusting circuit for wireless charging system Pending CN103595262A (en)

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Application Number Priority Date Filing Date Title
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Cited By (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN104300698A (en) * 2014-11-06 2015-01-21 哈尔滨工业大学 Resonance enhanced wireless power transmission structure with high resonance frequency stability
CN104868322A (en) * 2014-02-24 2015-08-26 苏州瑛日电子科技有限公司 Multifunctional electric energy output device
CN105245035A (en) * 2015-11-04 2016-01-13 华东交通大学 Frequency changer circuit based on magnetic resonance coupling wireless power transmission
WO2016181186A1 (en) * 2015-05-11 2016-11-17 Sia "Transfoelectric" A resonator for a wireless transfer system
CN107636935A (en) * 2015-05-15 2018-01-26 英特尔公司 For extended power ability and the reconfigurable charging station of active region
CN107959357A (en) * 2017-11-29 2018-04-24 歌尔科技有限公司 A kind of wireless charging receiving circuit, frequency adjusting method and smart machine
CN108242826A (en) * 2016-12-27 2018-07-03 全亿大科技(佛山)有限公司 Wireless charging transmitter and wireless charging method
WO2019076365A1 (en) * 2017-10-20 2019-04-25 Tian Jianlong Power conversion system and applications thereof
WO2020220174A1 (en) * 2019-04-28 2020-11-05 Oppo广东移动通信有限公司 Power matching method and apparatus for wireless charging, and wireless charging apparatus
CN115079069A (en) * 2022-07-25 2022-09-20 国仪量子(合肥)技术有限公司 Frequency-variable modulation field system, control method thereof and EPR spectrometer

Cited By (14)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN104868322B (en) * 2014-02-24 2017-10-10 苏州瑛日电子科技有限公司 A kind of multifunctional electric energy output device
CN104868322A (en) * 2014-02-24 2015-08-26 苏州瑛日电子科技有限公司 Multifunctional electric energy output device
CN104300698A (en) * 2014-11-06 2015-01-21 哈尔滨工业大学 Resonance enhanced wireless power transmission structure with high resonance frequency stability
CN104300698B (en) * 2014-11-06 2016-03-23 哈尔滨工业大学 There is the harmonic intensified wireless power transmission structure of high resonance frequency stability
WO2016181186A1 (en) * 2015-05-11 2016-11-17 Sia "Transfoelectric" A resonator for a wireless transfer system
CN107636935A (en) * 2015-05-15 2018-01-26 英特尔公司 For extended power ability and the reconfigurable charging station of active region
CN105245035A (en) * 2015-11-04 2016-01-13 华东交通大学 Frequency changer circuit based on magnetic resonance coupling wireless power transmission
CN108242826A (en) * 2016-12-27 2018-07-03 全亿大科技(佛山)有限公司 Wireless charging transmitter and wireless charging method
WO2019076365A1 (en) * 2017-10-20 2019-04-25 Tian Jianlong Power conversion system and applications thereof
CN107959357A (en) * 2017-11-29 2018-04-24 歌尔科技有限公司 A kind of wireless charging receiving circuit, frequency adjusting method and smart machine
WO2020220174A1 (en) * 2019-04-28 2020-11-05 Oppo广东移动通信有限公司 Power matching method and apparatus for wireless charging, and wireless charging apparatus
CN113615035A (en) * 2019-04-28 2021-11-05 Oppo广东移动通信有限公司 Power matching method and device for wireless charging and wireless charging device
EP3955417A4 (en) * 2019-04-28 2022-04-27 Guangdong Oppo Mobile Telecommunications Corp., Ltd. Power matching method and apparatus for wireless charging, and wireless charging apparatus
CN115079069A (en) * 2022-07-25 2022-09-20 国仪量子(合肥)技术有限公司 Frequency-variable modulation field system, control method thereof and EPR spectrometer

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