WO2023221263A1

WO2023221263A1 - Multi-load wireless charging system and charging method

Info

Publication number: WO2023221263A1
Application number: PCT/CN2022/103939
Authority: WO
Inventors: 龚文兰; 吴晓锐; 肖静; 陈绍南; 尹立群; 韩帅; 陈卫东; 莫宇鸿; 吴宁; 郭敏; 郭小璇; 张龙飞; 欧阳进; 陈炜智
Original assignee: 广西电网有限责任公司电力科学研究院
Priority date: 2022-05-16
Filing date: 2022-07-05
Publication date: 2023-11-23
Also published as: CN114726056B; CN114726056A

Abstract

A multi-load wireless charging system and a charging method. The charging system comprises a primary-side device and a secondary-side device. The primary-side device comprises an inverter, a selection switch, a primary-side resonant network, and a transmit coil, connected in sequence, and a primary-side control board connected to the inverter, the selection switch, the primary-side resonant network and the transmit coil. The secondary-side device comprises a receiving coil, a secondary-side resonant network, a rectifier circuit, and a battery connected in sequence, and a secondary-side control board connected to the receiving coil, the secondary-side resonant network, the rectifier circuit and the battery. Different batteries are charged by means of different transmit coils, and turn-on times of different coils are changed within a set period of time, so as to control charging speeds of the different batteries. This solves the problem of a primary-side device needing to be in different charging states due to different electricity quantities of batteries, while the primary-side device can only be in one charging state at a time.

Description

A multi-load wireless charging system and charging method

Technical field

The invention belongs to the technical field of wireless charging, and specifically relates to a multi-load wireless charging system and a charging method.

Background technique

Wireless power transmission has been widely used in consumer electronics, daily transportation, medical equipment, aerospace and other fields with its advantages of safety, convenience and space saving. Its non-contact energy transmission process has fundamentally changed all walks of life. industry’s energy use patterns. Compared with single-load systems, multi-load wireless charging systems make greater use of the transmitting coil and can power multiple devices at the same time. However, the cross-coupling problem between receiving coils in commonly used multi-load wireless charging systems and the different charging states due to different power levels are also a major problem in multi-load systems.

Contents of the invention

In order to solve the above problems, the present invention provides a multi-load wireless charging system and a charging method. The main solution is that in the multi-load wireless charging system, the primary device needs to be in different charging states due to different battery levels. However, the primary device Only one charge status issue can be provided at a time. At the same time, the problem of cross-coupling between receiving coils caused by the same type of receiving coils in a multi-load wireless charging system is solved. The specific technical solutions are as follows:

A multi-load wireless charging system includes primary-side equipment and secondary-side equipment. The primary-side equipment includes an inverter, a selection switch, a primary-side resonant network, and a transmitting coil connected in sequence. Primary control panel for switches, primary resonant network and transmitter coil;

The secondary device includes a receiving coil, a secondary resonant network, a rectifier circuit, and a battery that are connected in sequence, and a secondary control board that connects the receiving coil, the secondary resonant network, the rectifier circuit, and the battery; the transmit coil is connected to the corresponding The receiving coil is coupled; several primary-side resonant networks are set and connected to selector switches respectively; the number of the secondary-side devices matches the number of the primary-side resonant networks;

The secondary side control board is used to send the detected battery power to the primary side control board;

The primary side control board is used to judge the received battery power, select different primary side resonant networks, and calculate the opening time of each primary side resonant network to keep the primary side resonant network in an on or off state.

Preferably, the transmitting coil includes a square planar transmitting coil and a double D-shaped transmitting coil; the square planar transmitting coil overlaps with the double D-shaped transmitting coil.

Preferably, the receiving coil includes a square planar receiving coil and a double D-shaped receiving coil; the square planar receiving coil and the double D-shaped receiving coil are placed side by side on both sides of the transmitting coil.

A multi-load wireless charging method, applied to the multi-load wireless charging system, the steps include:

Step S1: The primary control board establishes communication with several secondary control boards respectively;

Step S2: Each secondary control board detects the power of the corresponding battery and transmits the detected data to the primary control board;

Step S3: The primary side control board calculates the opening time of each primary side resonant network based on the received battery power, and controls the opening and closing of the corresponding primary side resonant network based on the opening time of each primary side resonant network;

Step S4, when the primary side resonance network corresponding to the battery is opened, the primary side control board starts to control the charging of the battery;

Step S5: The primary side control board detects the received battery power and determines whether the battery is full. If it is full, it stops charging; if it is not full, it repeats S2.

Preferably, in step S3, the primary side control board calculates the opening time of each primary side resonant network based on the received battery power, specifically: the opening time of the resonant network i is ti-1~t1+t2+···+ti- 1+ti, the remaining time periods are turned off, where i=1,2,···,n;

When i=1, ti-1=0; where t1+t2+...+tn=T, T is a period; n is the number of primary resonant networks.

Preferably, there are two primary-side resonant networks, namely primary-side resonant network 1 and primary-side resonant network 2; the total opening time of the primary-side resonant network 1 and the primary-side resonant network 2 is one period T; The opening time of the primary side resonant network 1 is t1, and 0<=t1<=T, and the remaining time periods are turned off; the opening time of the primary side resonant network 2 is t2, and 0<=t2<=T, and the remaining time periods are turned off. Segment is turned off; t1+t2=T.

Preferably, the primary side control panel calculates the values of t1 and t2 according to the following conditions:

When SOC ₁ =SOC ₂ , t1/t2=1;

When 0<SOC ₁ -SOC ₂ ≤10%, t1/t2＝2/3;

When 20%<SOC ₁ -SOC ₂ ≤50%, t1/t2=1/2;

When 50%<SOC ₁ -SOC ₂ ≤90%, t1/t2=3/1;

Among them, SOC ₁ is the battery power of battery 1 corresponding to primary side resonant network 1, and SOC ₂ is the battery power of battery 2 corresponding to primary side resonant network 2.

The beneficial effects of the present invention are: the primary-side control board of the present invention determines the received battery power and controls the selection switch to select different primary-side resonant networks and opening times, so that the power of each battery reaches the same charge faster. state. The time division multiplexing method is used to regularly switch the transmitting coils connected to different primary side resonant networks, charge different batteries through different transmitting coils, and at the same time change the turn-on time of different coils within a certain period of time to control the charging speed of different batteries. This solves the problem that the primary device needs to be in different charging states due to different battery levels, but the primary device can only provide one charging state at the same time.

The transmitting coil can generate two different magnetic fields and can only couple with the corresponding receiving coil. At the same time, the decoupling characteristics of the double D-shaped coil and the planar coil are used to achieve decoupling between the secondary receiving coils and solve the problem of cross-coupling. The problem.

Description of the drawings

In order to more clearly explain the specific embodiments of the present invention or the technical solutions in the prior art, the drawings that need to be used in the description of the specific implementations or the prior art will be briefly introduced below. Throughout the drawings, similar elements or portions are generally identified by similar reference numerals. In the drawings, elements or parts are not necessarily drawn to actual scale.

Figure 1 is a schematic diagram of the system of the present invention;

Figure 2 is a schematic structural diagram of the transmitting coil and the receiving coil of the present invention;

Figure 3 is a schematic structural plan view of the transmitting coil and the receiving coil of the present invention;

Figure 4 is a flow chart of the method of the invention.

Detailed ways

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts fall within the scope of protection of the present invention.

It should be understood that, when used in this specification and the appended claims, the terms "comprises" and "comprises" indicate the presence of described features, integers, steps, operations, elements and/or components but do not exclude the presence of one or The presence or addition of multiple other features, integers, steps, operations, elements, components and/or collections thereof.

It should also be understood that the terminology used in the description of the present invention is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. As used in this specification and the appended claims, the singular forms "a", "an" and "the" are intended to include the plural forms unless the context clearly dictates otherwise.

It will be further understood that the term "and/or" as used in the specification and the appended claims refers to and includes any and all possible combinations of one or more of the associated listed items. .

As shown in Figures 1-3, the specific embodiment of the present invention provides a multi-load wireless charging system, including primary side equipment and secondary side equipment. The primary side equipment includes an inverter, a selection switch, and a primary side device connected in sequence. The side resonant network, the transmitting coil, and the primary side control board connecting the inverter, the selector switch, the primary side resonant network and the transmitting coil;

In this embodiment, there are 2 primary-side resonant networks and 2 secondary-side devices. The selector switch includes a selector switch K1 and a selector switch K2. The transmitter coil includes a square planar transmitter coil and a double D-shaped transmitter coil; The receiving coil includes a square planar receiving coil and a double D-shaped receiving coil. The square planar transmitting coil and the double D-shaped transmitting coil are placed overlappingly, and the square planar receiving coil and the double D-shaped receiving coil are placed side by side on both sides of the transmitting coil.

The primary side equipment consists of an inverter, selector switch K1, selector switch K2, primary side resonant network 1, primary side resonant network 2, flat square transmitting coil, double D transmitting coil and primary side control board; the secondary side equipment consists of a flat square It consists of receiving coil, double D receiving coil, secondary resonant network 1, secondary resonant network 2, rectifier circuit 1, rectifier circuit 2, battery 1, battery 2 and secondary control board.

The input end of the inverter is connected to the external input DC power supply; the output end of the inverter is connected in parallel to the selector switch K1 and the selector switch K2; the inverter converts the received DC power into an alternating current of a certain frequency to the selector switch 1 and the selector switch 2; Selector switch 1 and selector switch 2 control the inverter to be connected to the primary resonant network 1 and primary resonant network 2.

The selector switch K1, the primary side resonant network 1, and the planar square transmitting coil are connected in series; the mutual inductance between the planar square transmitting coil and the planar square receiving coil is the coupling mechanism 1; the planar square receiving coil, the secondary resonant network 1, the rectifier circuit 1, and the battery 1 Connect in series.

Selector switch K2, primary side resonant network 2, double D transmitting coil are connected in series in sequence; the mutual inductance between the double D transmitting coil and the double D receiving coil is coupling mechanism 2; double D receiving coil, secondary side resonant network 2, rectifier circuit 2, battery 2 Connect in series.

The primary resonant network 1 includes an inductor Lt1, a capacitor Cp1, and a capacitor Ct1; the inductor Lt1 and the capacitor Cp1 are connected in series; the capacitor Cp1 and the capacitor Ct1 are connected in parallel; one end of the inductor Lt1 is connected to the selection switch K1, and the other end is connected to one end of the capacitor Cp1 and the capacitor Ct1. One end of Ct1 is connected; the other end of the capacitor Cp1 is connected to one end of the planar square transmitting coil, and the other end of the capacitor Ct1 is connected to the other end of the planar square transmitting coil and the selection switch K2 respectively.

The primary resonant network 2 includes an inductor Lt2, a capacitor Cp2, and a capacitor Ct2; the inductor Lt2 and the capacitor Cp2 are connected in series; the capacitor Cp2 and the capacitor Ct2 are connected in parallel; one end of the inductor Lt2 is connected to the selection switch K1, and the other end is connected to one end of the capacitor Cp2 and the capacitor Ct2. One end of Ct2 is connected; the other end of the capacitor Cp2 is connected to one end of the double D-type transmitting coil, and the other end of the capacitor Ct2 is connected to the other end of the double D-type transmitting coil and the selector switch K2.

The principle of the system of the present invention is: the DC voltage outputs a high-frequency AC voltage through the inverter, and the above-mentioned high-frequency AC voltage passes through the selector switch 1 and the selector switch 2 to the primary side resonant network 1, where the selector switch 1 and the selector switch 2 are connected to The connection time of the primary side resonant network 1 is t1. The AC voltage generates a time-varying magnetic field through the square planar transmitting coil. The corresponding square planar receiving coil generates an alternating current under the time-varying magnetic field. The AC voltage passes through the secondary side resonant network 1 to Rectifier circuit 1 outputs DC power to charge battery 1;

The above-mentioned high-frequency AC voltage passes through the selector switch 1 and the selector switch 2 to the primary side resonant network 2, where the selector switch 1 and the selector switch 2 are connected to the primary side resonant network 2 for a time of t2. This alternating current generates a time-varying signal through the double D transmitting coil. Magnetic field, the corresponding double D receiving coil generates an alternating current under the time-varying magnetic field. The alternating current passes through the secondary resonant network 2 to the rectifier circuit 2 and outputs direct current to charge the battery 2; among them, t1 and t2 change according to changes in battery power.

As shown in Figure 4, the specific embodiment of the present invention also provides a multi-load wireless charging method, which is applied to the multi-load wireless charging system. The steps include:

Step S1: The primary control board establishes communication with several secondary control boards respectively.

Step S2: Each secondary control board detects the power of the corresponding battery and transmits the detected data to the primary control board.

Step S3: The primary side control board calculates the opening time of each primary side resonant network based on the received battery power, and controls the opening and closing of the corresponding primary side resonant network according to the opening time of each primary side resonant network; where, The side control board calculates the opening time of each primary side resonant network based on the received battery power, specifically: the opening time of the resonant network i is ti-1~t1+t2+···+ti-1+ti, and the other time periods are closed Break, where i=1,2,···,n;

When i=1, ti-1=0; where t1+t2+...+tn=T, T is a period; n is the number of primary resonant networks. The opening and closing time periods of each resonant network in the next cycle are performed according to the above steps.

Step S4: After the primary side resonance network corresponding to the battery is opened, the primary side control board begins to control charging of the battery.

Step S5: The primary side control board detects the received battery power and determines whether the battery is full. If it is full, it will stop charging; if it is not full, it will repeat S2.

Assume that the square planar coil is coil 1, and the double D-shaped coil is coil 2; the resonant network corresponding to the square planar coil is resonant network 1, and the resonant network corresponding to the double D coil is resonant network 2; the battery corresponding to coil 1 is battery 1, and the coil The battery corresponding to 2 is battery 2. The total opening time of the primary side resonant network 1 and the primary side resonant network 2 is one cycle T; the opening time of the primary side resonant network 1 is t1, and 0<=t1<=T, and the remaining time periods are turned off; The primary side resonant network 2 is turned on for t2, and 0<=t2<=T, and is turned off for the remaining time periods; t1+t2=T.

The selection switch 1 and the selection switch 2 are connected to the primary resonant network 1 for a time of t1. The alternating current generates a time-varying magnetic field through the square planar transmitting coil, and the corresponding square planar receiving coil generates an alternating current under the time-varying magnetic field. The alternating current Outputs DC power through the secondary resonant network 1 to the rectifier circuit 1 to charge the battery 1;

The high-frequency alternating current passes through selector switch 1 and selector switch 2 to the primary side resonant network 2. The connection time between selector switch 1 and selector switch 2 and the primary resonant network 2 is t2. The alternating current generates a time-varying magnetic field through the double D transmitting coil. The corresponding double D receiving coil generates an alternating current under the time-varying magnetic field. The alternating current passes through the secondary resonant network 2 to the rectifier circuit 2 and outputs direct current to charge the battery 2, where t1+t2=1s.

The primary side control panel calculates the values of t1 and t2 based on the following conditions:

When SOC ₁ =SOC ₂ , t1/t2=1;

When 0<SOC ₁ -SOC ₂ ≤10%, t1/t2＝2/3;

When 20%<SOC ₁ -SOC ₂ ≤50%, t1/t2=1/2;

When 50%<SOC ₁ -SOC ₂ ≤90%, t1/t2=3/1;

Those of ordinary skill in the art will appreciate that the units of each example described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, computer software, or a combination of both. In order to clearly illustrate the interchangeability of hardware and software In the above description, the composition of each example has been generally described according to its function. Whether these functions are performed in hardware or software depends on the specific application and design constraints of the technical solution. Skilled artisans may implement the described functionality using different methods for each specific application, but such implementations should not be considered to be beyond the scope of the present invention.

In the embodiments provided in this application, it should be understood that the division of units is only a logical function division. In actual implementation, there may be other division methods. For example, multiple units may be combined into one unit, and one unit may be detached. Divided into multiple units, or some features can be ignored, etc.

Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of the present invention, but not to limit it. Although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that: The technical solutions described in the foregoing embodiments can still be modified, or some or all of the technical features can be equivalently replaced; and these modifications or substitutions do not deviate from the essence of the corresponding technical solutions from the technical solutions of the embodiments of the present invention. scope, they should be covered by the claims and the scope of the description of the present invention.

Claims

A multi-load wireless charging system, characterized in that it includes primary-side equipment and secondary-side equipment. The primary-side equipment includes an inverter, a selection switch, a primary-side resonant network, a transmitting coil, and a connected inverter. primary side control panel of the inverter, selector switch, primary side resonant network and transmitting coil;

The secondary device includes a receiving coil, a secondary resonant network, a rectifier circuit, and a battery that are connected in sequence, and a secondary control board that connects the receiving coil, the secondary resonant network, the rectifier circuit, and the battery; the transmit coil is connected to the corresponding The receiving coil is coupled; several primary-side resonant networks are set and connected to selector switches respectively; the number of the secondary-side devices matches the number of the primary-side resonant networks;

The secondary side control board is used to send the detected battery power to the primary side control board;

The primary side control board is used to judge the received battery power, select different primary side resonant networks, and calculate the opening time of each primary side resonant network to keep the primary side resonant network in an on or off state.
A multi-load wireless charging system according to claim 1, wherein the transmitting coil includes a square planar transmitting coil and a double D-shaped transmitting coil; the square planar transmitting coil overlaps the double D-shaped transmitting coil place.
A multi-load wireless charging system according to claim 2, characterized in that the receiving coil includes a square planar receiving coil and a double D-shaped receiving coil; the square planar receiving coil and the double D-shaped receiving coil are placed side by side. on both sides of the transmitting coil.
A multi-load wireless charging method, characterized in that it is applied to the multi-load wireless charging system according to any one of claims 1-3, and the steps include:

Step S1: The primary control board establishes communication with several secondary control boards respectively;

Step S2: Each secondary control board detects the power of the corresponding battery and transmits the detected data to the primary control board;

Step S3, the primary side control board calculates the opening time of each primary side resonant network based on the received battery power, and controls the opening and closing of the corresponding primary side resonant network based on the opening time of each primary side resonant network;

Step S4, when the primary side resonance network corresponding to the battery is opened, the primary side control board starts to control the charging of the battery;

Step S5: The primary side control board detects the received battery power and determines whether the battery is full. If it is full, it stops charging; if it is not full, it repeats S2.
A multi-load wireless charging method according to claim 4, characterized in that in step S3, the primary side control board calculates the activation time of each primary side resonance network based on the received battery power, specifically: resonance network i The turn-on time is ti-1~t1+t2+…+ti-1+ti, and the remaining time periods are turned off, where i=1,2,…,n;

When i=1, ti-1=0; where t1+t2+...+tn=T, T is a period; n is the number of primary resonant networks.
A multi-load wireless charging method according to claim 5, characterized in that there are two primary-side resonant networks, namely primary-side resonant network 1 and primary-side resonant network 2; said primary-side resonant network 1 The sum of the opening time of the primary side resonant network 2 and the opening time of the primary side resonant network 2 is one cycle T; the opening time of the primary side resonant network 1 is t1, and 0<=t1<=T, and the remaining time periods are turned off; the primary side resonant network 2 The turn-on time is t2, and 0<=t2<=T, and it is turned off in the remaining time periods; t1+t2=T.
A multi-load wireless charging method according to claim 6, characterized in that the primary side control board calculates the values of t1 and t2 according to the following conditions:

When SOC 1 =SOC 2 , t1/t2=1;

When 0<SOC 1 -SOC 2 ≤10%, t1/t2＝2/3;

When 20%<SOC 1 -SOC 2 ≤50%, t1/t2=1/2;

When 50%<SOC 1 -SOC 2 ≤90%, t1/t2=3/1;

Among them, SOC 1 is the battery power of battery 1 corresponding to primary side resonant network 1, and SOC 2 is the battery power of battery 2 corresponding to primary side resonant network 2.