WO2018129961A1

WO2018129961A1 - Magnetic coupling resonant power emission end having multiple resonant circuits connected in parallel, receiving end, and system

Info

Publication number: WO2018129961A1
Application number: PCT/CN2017/104460
Authority: WO
Inventors: 范金焰
Original assignee: 上海蔚来汽车有限公司
Priority date: 2017-01-13
Filing date: 2017-09-29
Publication date: 2018-07-19
Also published as: CN106602733A; CN106602733B

Abstract

A magnetic coupling resonant power emission end (02) having multiple resonant circuits connected in parallel, a receiving end (03), and a system (01), comprising: an emission end (02), which accesses a direct current voltage power supply, and a receiving end (03), which is connected to an output voltage; the emission end (02) comprises therein two or more emission circuit units (04), each emission circuit unit (04) comprising an emission resonant circuit (05) and an inverting circuit (06), which is used for driving the emission resonant circuit (05), and an input end of each inverting circuit (06) being connected in parallel; the number of receiving circuit units (07) is the same as the number of the emission circuit units (04) in the emission end (02), and each receiving circuit unit (07) comprises a receiving resonant circuit (08), which is provided in correspondence with the emission resonant circuit (05) in the emission circuit unit (04), and a rectifying and outputting circuit (09), an output end of each rectifying and outputting circuit (09) being connected in parallel. Said solution solves the problem wherein a high current may not pass through a MOS tube, and relative to existing solutions, lowers the operating voltage of a resonant capacitor when transmitting the same power, thereby lowering costs and promoting the wide application of wireless charging in the field of electric vehicle charging.

Description

Magnetically coupled resonance energy transmitting end, receiving end and system with multiple resonant circuits connected in parallel

Technical field

The present invention relates to the field of wireless charging technologies, and in particular, to a magnetically coupled resonant power transmitting end, a receiving end and a system in which multiple resonant circuits are connected in parallel.

Background technique

In the wireless charging system based on the principle of magnetic coupling resonance, the resonant current is very large. Currently, the MOSFET (Metal-Oxide-Semiconductor Field-Effect Transistor) has the same meaning, and all of the following appear. MOSFETs are replaced by MOS transistors.) The on-state current capability is limited, and multiple MOS transistors are connected in parallel to reduce reliability. When high-power transmission power is required, the resonant capacitor voltage is very high; this leads to high manufacturing cost.

Facing the above problems, in the prior art, the following solutions are proposed. As shown in FIG. 1 , although this solution theoretically solves the problem of the on-state current limit of the MOS tube, a large transmission power can be realized, but the actual The resonant voltage of the upper resonant capacitor will be very high. If the power above 10KW is transmitted, the resonant voltage will be as high as 10KV. At present, the manufacturing process of this high-voltage capacitor is still immature and the manufacturing cost is high, and the resonant cavity needs high voltage operation. The characteristics also bring security problems; the current MOS tube parallel application has a series of reliability problems due to the change of temperature coefficient in its conduction mode.

Summary of the invention

In order to solve the above problems in the prior art, in order to solve the problem that the MOS tube cannot be excessively current, how to reduce the working voltage of the resonant capacitor, thereby reducing the cost, and promoting the popularization and application of wireless charging in the field of electric vehicle charging, the present invention provides A multi-resonant circuit in parallel with a magnetically coupled resonant power transmitting end, the transmitting end is connected with a DC voltage power supply, the transmitting end includes two or more transmitting circuit units, and each transmitting circuit unit includes a transmitting resonance The circuit and the inverter circuit for driving the transmitting resonant circuit are connected in parallel with each input end of the inverter circuit.

Preferably, the resonant coils in all of the transmit resonant circuits form an array of transmit coils.

Preferably, each of the resonant coils constituting the array of transmitting coils is disposed in a plane.

Preferably, each of the resonant coils constituting the array of the transmitting coils is a planar coil.

Preferably, a compensation capacitor is connected in series in the transmission resonant circuit.

Preferably, the emission resonant circuit is a CLC resonant circuit.

Preferably, the inverter circuit is a full bridge inverter circuit.

Preferably, the PWM switching frequency of the full bridge inverter circuit is 85 kHz.

The invention also provides a magnetic resonance resonant power receiving end of a multi-resonant circuit connected in parallel, the receiving end is connected with an output voltage, the receiving end comprises a receiving circuit unit, and the number of the receiving circuit unit is parallel with the multi-resonant circuit The number of transmitting circuit units in the transmitting end is the same, and each receiving circuit unit includes a receiving resonant circuit corresponding to the transmitting resonant circuit in the transmitting circuit unit, and a rectifying output circuit, and the output ends of the respective rectified output circuits are connected in parallel.

Preferably, the resonant coils in all of the receiving resonant circuits form an array of receiving coils.

Preferably, each of the resonant coils constituting the array of receiving coils is disposed in a plane.

Preferably, a compensation capacitor is connected in series in the receiving resonant circuit.

Preferably, the receiving resonant circuit is a CLC resonant circuit.

Preferably, the rectified output circuit is a bridge rectifier circuit.

The invention also provides a magnetically coupled resonance electrical energy system in which multiple resonant circuits are connected in parallel, comprising a transmitting end and a receiving end.

Preferably, the inductance values of the resonant coils in the transmitting resonant circuit and the receiving resonant circuit are equal, and the capacitance values of the compensation capacitors in the transmitting resonant circuit and the receiving resonant circuit are equal.

Compared with the prior art, the present invention has at least the following advantages:

Through the design of the magnetic coupling resonance electric energy system in parallel with the multi-resonance circuit of the invention, the problem that the MOS tube can not be excessively large is solved, and under the condition of transmitting the same power, the working voltage of the resonant capacitor is lowered compared with the existing scheme, thereby reducing The cost has promoted the popularization of wireless charging in the field of electric vehicle charging.

DRAWINGS

1 is a schematic diagram of wiring provided in the prior art for solving the problem of the on-state current limit of a power tube;

2 is a schematic diagram showing the connection of a magnetically coupled resonant power system in which multiple resonant circuits are connected in parallel according to the present invention;

3 is a schematic diagram showing the specific wiring of a magnetically coupled resonant power system in which two resonant circuits are connected in parallel according to the present invention;

4 is a schematic diagram of a resonant coil in a transmitting end of the same plane provided by the present invention.

detailed description

Preferred embodiments of the present invention are described below with reference to the accompanying drawings. Those skilled in the art should understand that these embodiments are only used to explain the technical principles of the present invention, and are not intended to limit the scope of the present invention.

The invention solves the contradiction between the high-power wireless charging resonant current and the MOS tube not being too large, and solves the contradiction between the high-power wireless charging resonant current and the MOS tube not exceeding the current, and promotes the wireless charging in the electric vehicle charging field. Universal application.

The invention provides a magnetic resonance resonant power transmitting end of a multi-resonant circuit in parallel, and a magnetic coupling resonant power receiving end of a multi-resonant circuit in parallel, and a multi-resonant circuit composed of the transmitting end and the receiving end are connected in parallel Magnetically coupled resonant power system. In order to more clearly describe the circuit configuration and operation principle of the present invention, the transmitting end, the receiving end, and the system will be generally described from the perspective of a magnetically coupled resonant power system in which multiple resonant circuits are connected in parallel.

In the present invention, a magnetically coupled resonant power system in which multiple resonant circuits are connected in parallel is provided. As shown in FIG. 2, the magnetically coupled resonant power system 01 includes a magnetically coupled resonant power transmitting end 02 in which multiple resonant circuits are connected in parallel, and a multi-resonant circuit. Parallel magnetically coupled resonant power receiving end 03, transmitting end 02 converts electrical energy into electromagnetic energy, receiving end 03 converts electromagnetic energy into electrical energy, and said transmitting end 02 includes two or more transmitting circuit units 04, each The transmitting circuit unit 04 includes a transmitting resonant circuit 05 and an inverter circuit 06 for driving the transmitting resonant circuit 05, and the input terminals of the respective inverter circuits 06 are connected in parallel; the receiving end 02 includes a receiving circuit unit 07, and the receiving circuit unit The number of 07 is the same as the number of transmitting circuit units 04 in the transmitting end 02 in parallel with the aforementioned multi-resonant circuit, and each receiving circuit unit 07 includes a receiving resonant circuit 08 corresponding to the transmitting resonant circuit 05 in the transmitting circuit unit 04, and rectification The output circuit 09 and the output ends of the respective rectified output circuits 09 are connected in parallel.

The resonant coils in all the transmitting resonant circuits 05 constitute an array of transmitting coils, and the resonant coils constituting the transmitting coil array are disposed in the same plane, and the resonant coils constituting the transmitting coil array are planar coils; all receiving resonant circuits 08 The resonant coils in the middle constitute a receiving coil array, and the resonant coils constituting the receiving coil array are disposed in a plane, and the resonant coils constituting the receiving coil array are planar coils; the transmitting resonant circuit 05 and the receiving resonant circuit 08 are The inductance values of the resonant coils are equal; in practical applications, the resonant coils in the array of transmitting coils and the resonant coils in the array of receiving coils are correspondingly arranged. Regardless of the respective resonant coils constituting the transmitting coil array or the respective resonant coils constituting the receiving coil array, the respective resonant coils do not overlap each other. As shown in FIG. 4, the resonant coils L ₁ and L ₂ are disposed in the same plane. In a preferred embodiment, the predetermined spacing distance between the resonant coils is preferably not less than 5 cm.

The transmitting resonant circuit 05 and the receiving resonant circuit 08 are each connected in series with a compensation capacitor, and the capacitance values of the compensation capacitors in the transmitting resonant circuit 05 and the receiving resonant circuit 08 are equal; the transmitting resonant circuit 05 and the receiving resonant circuit 08 are both It is a CLC resonant circuit.

In the transmitting end 02 of the magnetic coupling resonant power system 01 of the present invention, two or more selected radiating resonant circuits 04 are selected, which can realize that the MOS tube to be solved cannot be excessively current, and how to reduce the resonant capacitor. The working voltage, which in turn reduces the cost, promotes the popularization of wireless charging in the field of electric vehicle charging, especially the design of two resonant circuits 04 is optimal. The following description is directed to the preferred embodiment employing two resonant circuits 04 as an embodiment.

In this embodiment, as shown in FIG. 3, the DC voltage source is U, and two transmit resonant circuits (the compensation capacitor C ₁ , the resonant coil L ₁ and the compensation capacitor C ₂ form a transmit resonant circuit, and the compensation capacitor C ₃ The resonant coil L ₂ and the compensation capacitor C ₄ constitute another transmitting resonant circuit), and the corresponding two receiving resonant circuits (the compensation capacitor C ₅ , the resonant coil L ₃ and the compensation capacitor C ₆ form a receiving resonant circuit, and the compensation capacitor C _{7. The} resonant coil L ₄ and the compensation capacitor C ₈ constitute another receiving resonant circuit); wherein

C ₁ = C ₂ = C ₃ = C ₄ = C ₅ = C ₆ = C ₇ = C ₈

L ₁ = L ₂ = L ₃ = L ₄

The resonance frequency f=85000HZ, the calculation formula is:

In the above formula, L = L ₁ = L ₂ = L ₃ = L ₄

C=C ₁ +C ₂ =C ₃ +C ₄ =C ₅ +C ₆ =C ₇ +C ₈

Specifically, after the DC voltage of the DC voltage source U is output, when the PWM (Pulse Width Modulation) driving signal applied to the switching circuit of the inverter circuit is a square wave, (the PWM switching frequency is 85 kHz) The DC voltage is inverted to an AC square wave voltage of 85,000 Hz, which drives the C ₁ L ₁ C ₂ emission resonant circuit to resonate with the C ₃ L ₂ C ₄ transmit resonant circuit, generating an alternating magnetic field in space, receiving The C ₅ L ₃ C ₆ receiving resonant circuit and the C ₇ L ₄ C ₈ receiving resonant circuit resonate with the transmitting resonant circuit, and the resonant sinusoidal voltage is outputted by the rectified output circuit to become the DC voltage V _out .

The inverter circuit in the transmitting end of the magnetically coupled resonant power system is a full bridge inverter circuit, and the PWM switching frequency of the full bridge inverter circuit is 85 kHz; the rectified output circuit is a bridge rectifier circuit.

The multi-resonant circuit in parallel with the multi-resonant circuit has a multi-resonant circuit connected in parallel with the magnetically coupled resonance electric energy transmitting end 02, and the multi-resonant circuit is connected in parallel with the magnetically coupled resonant electric energy receiving end 03, and the transmitting end 02 is connected with a DC voltage power supply. The receiving end 03 is connected with an output voltage. For example, in the electric vehicle field, the transmitting end 02 is disposed at the charging station and the receiving end 03 is disposed in the vehicle body. Only when the electric vehicle is charged, the transmitting end 02 and the receiving end 03 cooperate with each other to realize electric energy. Wireless transmission.

Heretofore, the technical solutions of the present invention have been described in conjunction with the preferred embodiments shown in the drawings, but it is obvious to those skilled in the art that the scope of the present invention is obviously not limited to the specific embodiments. Those skilled in the art can make equivalent changes or substitutions to the related technical features without departing from the principles of the present invention, and the technical solutions after the modifications or replacements fall within the scope of the present invention.

Claims

A multi-resonant circuit is connected in parallel with a magnetically coupled resonant power transmitting end, and the transmitting end is connected with a DC voltage power supply, wherein the transmitting end includes two or more transmitting circuit units, and each transmitting circuit The unit includes a transmitting resonant circuit and an inverter circuit for driving the transmitting resonant circuit, and the input ends of the respective inverter circuits are connected in parallel.
The transmitting end according to claim 1, wherein the resonant coils in all of the transmitting resonant circuits form an array of transmitting coils.
The transmitting end according to claim 2, wherein each of the resonant coils constituting the array of the transmitting coils is disposed in a plane.
The transmitting end according to claim 3, wherein each of the resonant coils constituting the transmitting coil array is a planar coil.
The transmitting end according to any one of claims 1 to 4, characterized in that the transmitting resonant circuit has a compensation capacitor connected in series.
The transmitting end according to claim 5, wherein said transmitting resonant circuit is a CLC resonant circuit.
The transmitting end according to any one of claims 1 to 4, wherein the inverter circuit is a full bridge inverter circuit.
The transmitting end according to claim 7, wherein the full-bridge inverter circuit has a PWM switching frequency of 85 kHz.
A magnetically coupled resonant power receiving end connected in parallel with a multi-resonant circuit, wherein the receiving end is connected with an output voltage, wherein the receiving end comprises a receiving circuit unit, and the number of the receiving circuit unit is in any one of claims 1-8 A multi-resonant circuit has the same number of transmitting circuit units in a transmitting end in parallel, and each receiving circuit unit includes and transmits in the transmitting circuit unit The resonant circuit is provided with a receiving resonant circuit and a rectifying output circuit, and the output ends of the respective rectified output circuits are connected in parallel.
The receiving end according to claim 9, wherein the resonant coils in all of the receiving resonant circuits form an array of receiving coils.
The receiving end according to claim 10, wherein each of the resonant coils constituting the array of receiving coils is disposed in a plane.
The receiving end according to claim 11, wherein each of the resonant coils constituting the receiving coil array is a planar coil.
The receiving end according to any one of claims 9 to 12, characterized in that the receiving resonant circuit has a compensation capacitor connected in series.
The receiving end according to claim 13, wherein said receiving resonant circuit is a CLC resonant circuit.
The receiving end according to any one of claims 9 to 12, wherein the rectified output circuit is a bridge rectifying circuit.
A magnetically coupled resonant power system in which a plurality of resonant circuits are connected in parallel, comprising the transmitting end according to any one of claims 1 to 8 and the receiving end according to any one of claims 9 to 15.
A magnetically coupled resonance power system according to claim 16, wherein an inductance value of said resonant coil in said transmitting resonant circuit and said receiving resonant circuit is equal, said radiating resonant circuit and said compensating capacitor in said receiving resonant circuit The capacitance values are equal.