A strong anti-deviation wireless power transmission system based on topology parameter reconstruction and its control method

Abstract

The present invention discloses a strong anti-offset wireless power transmission system based on topological parameter reconstruction and a control method thereof. The system includes: a voltage sampling circuit, a driving circuit, a power transmitting end and a power receiving end; the voltage sampling circuit is used to receive a charging instruction issued by the power receiving end, and output a voltage sampling, and then generate PWM based on the voltage sampling; the driving circuit controls the power transmitting end to perform a charging operation based on PWM; the power transmitting end is used to charge the power receiving end; and the power receiving end is used to receive the electric energy emitted by the power transmitting end. In the present invention, when the coupling coefficient between coils changes in a wide range (0.1~0.4), the fluctuation of the system output is less than 1.6%, and the system efficiency can be maintained at more than 80%. The additional period is all located on the power transmitting side, which is conducive to the miniaturization and lightweight of the power receiving side.

Description

Technical Field

[0001] The present invention relates to the technical field of wireless power transmission, and in particular to a highly anti-deviation wireless power transmission system based on topology parameter reconstruction and a control method thereof. Background Art

[0002] Wireless power transmission technology has attracted much attention in many fields such as electric vehicles, underwater vehicles and implantable medical devices due to its advantages such as safety, reliability and convenience. However, in the actual application of wireless power transmission systems, the change of coupling coefficient caused by the position offset of the coupling coil will cause drastic fluctuations in the system output. How to ensure the stability of the system output when the coupling coefficient changes is one of the key issues in the research of wireless power technology.

[0003] In related wireless power transmission technologies, the system output fluctuation caused by coil offset is often alleviated from the perspective of magnetic coupler design and topology design. The anti-offset technology of wireless power transmission system based on magnetic coupler design can effectively alleviate the change of coupling coefficient caused by coil misalignment, thereby reducing output fluctuation. However, from the perspective of coupler design alone, it is impossible to avoid the deviation of system output from normal working state when the coil position is extremely offset. The parameter design process of wireless power transmission anti-offset technology based on topology design is complex, the number of components is large, and the offset range and direction are limited by the magnetic coupler. Summary of the invention

[0004] The present invention aims to solve the deficiencies of the prior art and provides the following solutions:

[0005] A highly anti-offset wireless power transmission system based on topology parameter reconstruction, comprising: a voltage sampling circuit, a driving circuit, a power transmitting end and a power receiving end;

[0006] The voltage sampling circuit is used to receive the charging instruction sent by the power receiving end, and output the voltage sampling, and then generate PWM based on the voltage sampling;

[0007] The driving circuit controls the power sending end to perform a charging operation based on PWM;

[0008] The power transmitting end is used to charge the power receiving end;

[0009] The power receiving end is used to receive the power sent by the power sending end.

[0010] Preferably, the power transmitting end is composed of a full-bridge inverter, a transmitting side compensation inductor, a first transmitting side compensation capacitor, a second transmitting side compensation capacitor and a power transmitting coil;

[0011] The full-bridge inverter is composed of four MOSFET diodes connected;

[0012] The transmitting side compensation inductor is composed of a switch, an inductor, two capacitors and a MOSFET diode connected;

[0013] The first transmitting side compensation capacitor is composed of a switch, two capacitors and a MOSFET diode connected together.

[0014] Preferably, the power receiving end is composed of a power receiving coil, a receiving side compensation network, an uncontrolled rectifier and a filter capacitor;

[0015] The receiving side compensation network is composed of two capacitors and one inductor connected;

[0016] The uncontrolled rectifier is composed of four diodes.

[0017] The present invention also provides a control method for a highly anti-deviation wireless power transmission system based on topology parameter reconstruction, the control method being used to control any of the above-mentioned power transmission systems, comprising the following steps:

[0018] After the power receiving end enters the charging area and sends a charging signal, the system starts working;

[0019] After receiving the charging signal, the voltage sampling circuit collects the voltage across the load and compares the sampled voltage with the reference voltage U ref The size of the power transmitting coil and the power receiving coil is determined to determine whether there is an offset;

[0020] Under the initial conditions of the system, when an offset occurs between the coils, the system output voltage U out will be less than the reference voltage U ref , and then adjust the duty cycle to make U out Increase until U is satisfied out ≥U ref After that, a PWM driving signal is generated;

[0021] The driving circuit controls the values ​​of the transmission-side compensation inductor and the first transmission-side compensation capacitor based on PWM to perform a charging operation.

[0022] Compared with the prior art, the present invention has the following beneficial effects:

[0023] The wireless power transmission system proposed in the present invention has the following advantages: (1) when the inter-coil coupling coefficient varies in a wide range (0.1-0.4), the fluctuation of the system output is less than 1.6%, and the system efficiency can be maintained above 80%; (2) the anti-offset method is applicable to wireless power transmission systems using different magnetic coupler structures; (3) the additional periods are all located on the power transmitting side, which is conducive to the miniaturization and lightweight of the power receiving side. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] In order to more clearly illustrate the technical solution of the present invention, the following briefly introduces the drawings required for use in the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

[0025] Figure 1 is a schematic diagram of a system circuit according to an embodiment of the present invention;

[0026] Figure 2 Schematic diagram of system control flow of an embodiment of the present invention. DETAILED DESCRIPTION

[0027] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0028] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the present invention is further described in detail below with reference to the accompanying drawings and specific embodiments.

[0029] Example

[0030] In this embodiment, if Figure 1 As shown, a strong anti-offset wireless power transmission system based on topology parameter reconstruction includes: a voltage sampling circuit, a driving circuit, a power transmitting end and a power receiving end. L is the resistance value of the load.

[0031] The voltage sampling circuit is used to receive the charging instruction issued by the power receiving end and output the voltage sampling, and then generate PWM based on the voltage sampling; the driving circuit controls the power sending end to perform the charging operation based on PWM; the power sending end is used to charge the power receiving end; the power receiving end is used to receive the electric energy sent by the power sending end.

[0032] The electric energy sending end is composed of a full-bridge inverter, a sending side compensation inductor, a first sending side compensation capacitor, a second sending side compensation capacitor and an electric energy sending coil; the full-bridge inverter is composed of four MOSFET diodes; the sending side compensation inductor is composed of a switch, an inductor, two capacitors and a MOSFET diode; the first sending side compensation capacitor is composed of a switch, two capacitors and a MOSFET diode.

[0033] In this embodiment, if Figure 1 As shown in FIG. 1 , the full-bridge inverter is composed of four MOSFET diodes S1, S2, S3 and S4 connected together; the supplementary inductance on the sending side is composed of switch G1, inductor L s1 , capacitor C s1 , capacitor C s2 and MOSFET diode; the first transmission side compensation capacitor is composed of switch G2, capacitor C s3 , capacitor C s4 and a MOSFET diode are connected; the second sending side compensation capacitor is C2; and the internal resistance of the power sending coil L2 is R1.

[0034] The power receiving end is composed of a power receiving coil, a receiving side compensation network, an uncontrolled rectifier and a filter capacitor; the receiving side compensation network is composed of two capacitors and one inductor; and the uncontrolled rectifier is composed of four diodes.

[0035] In this embodiment, if Figure 1 As shown, the receiving side compensation network is composed of capacitors C3, C4 and inductor L4; the uncontrolled rectifier is composed of four diodes D1, D2, D3 and D4; the filter capacitor is C5; and the internal resistance of the power receiving coil L3 is R2.

[0036] In this embodiment, a control method for a highly anti-deviation wireless power transmission system based on topology parameter reconstruction is also provided. Figure 2 As shown, the following steps are included:

[0037] After the power receiving end enters the charging area and sends a charging signal, the system starts working; after the voltage sampling circuit receives the charging signal, it collects the voltage across the load and compares the sampled voltage with the reference voltage U ref The size of determines whether the power sending coil and the power receiving coil are offset; under the initial conditions of the system, when the coils are offset, the system output voltage U out will be less than the reference voltage U ref , and then by adjusting the duty cycle D a and D b make U out Increase until U is satisfied out ≥U ref (Considering the sampling error, U out =U ref The extreme case is difficult to implement, so through U out ≥U ref After determining whether the system is working in a preset state, a PWM driving signal is generated; the driving circuit controls the values ​​of the sending side compensation inductor and the first sending side compensation capacitor based on PWM to perform a charging operation.

[0038] The embodiments described above are only descriptions of the preferred embodiments of the present invention and are not intended to limit the scope of the present invention. Without departing from the design spirit of the present invention, various modifications and improvements made to the technical solutions of the present invention by ordinary technicians in this field should all fall within the protection scope determined by the claims of the present invention.

Claims

1. A highly anti-deviation wireless power transmission system based on topology parameter reconstruction, characterized in that: include: Voltage sampling circuit, driving circuit, power transmitting end and power receiving end; The voltage sampling circuit is used to receive the charging instruction sent by the power receiving end, and output the voltage sampling, and then generate PWM based on the voltage sampling; The driving circuit controls the power sending end to perform a charging operation based on PWM; The power transmitting end is used to charge the power receiving end; The power receiving end is used to receive the power sent by the power sending end; The power sending end is composed of a full-bridge inverter, a sending side compensation inductor, a first sending side compensation capacitor, a second sending side compensation capacitor and a power sending coil; The full-bridge inverter is composed of four MOSFET diodes connected; The transmitting side compensation inductor is composed of a switch, an inductor, two capacitors and a MOSFET diode connected; The first transmitting side compensation capacitor is composed of a switch, two capacitors and a MOSFET diode connected; The power receiving end is composed of a power receiving coil, a receiving side compensation network, an uncontrolled rectifier and a filter capacitor; The receiving side compensation network is composed of two capacitors and one inductor connected; The uncontrolled rectifier is composed of 4 diodes; After the power receiving end enters the charging area and sends a charging signal, the system starts working; After receiving the charging signal, the voltage sampling circuit collects the voltage across the load and compares the sampled voltage with the reference voltage. U ref The size of the power transmitting coil and the power receiving coil is determined to determine whether there is an offset; Under the initial conditions of the system, when an offset occurs between the coils, the system output voltage U out will be less than the reference voltage U ref , and then by adjusting the duty cycle U out Increase until satisfied U out ≥ U ref After that, a PWM driving signal is generated; The driving circuit controls the values ​​of the transmission-side compensation inductor and the first transmission-side compensation capacitor based on PWM to perform a charging operation.

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