Constant-current and constant-voltage double-type load WPT system applied to AGV

Abstract

The invention relates to the technical field of wireless charging, and particularly discloses a constant-current and constant-voltage double-type load WPT system applied to an AGV, and the system comprises a transmitting end Q coil LTA which is horizontally stacked on a transmitting end ferrite, and a transmitting end solenoid coil LTB which is wound on the transmitting end Q coil LTA and the transmitting end ferrite to form a transmitting end charging disc; the receiving end Q coil LRA is horizontally stacked on the receiving end ferrite, and the receiving end solenoid coil LRB is wound on the receiving end Q coil LRA and the receiving end ferrite to form a receiving end charging disc; and the transmitting end charging disc and the receiving end charging disc are horizontally and oppositely arranged to form a systematic compact decoupling magnetic coupler. The beneficial effects are that the magnetic coupler does not have extra cross coupling, the system design is simplified, and the compactness of the system is improved; the system is composed of two transmitting ends and two receiving ends, the two receiving ends are both composed of S-shaped compensation topologies, the design cost of the system is reduced, and constant current output and constant voltage output irrelevant to loads can be provided for different power modules in the AVG at the same time.

Description

Technical Field

[0001] The present invention relates to the field of wireless charging technology, and in particular to a WPT system for constant current and constant voltage dual-type loads applied to AGVs. Background Art

[0002] Wireless Power Transfer (WPT) systems are widely used in automated guided vehicles, drones, electric vehicles and other fields due to their convenience, safety and reliability. Different types of power modules inside automated guided vehicles require different types of power supply methods, so a WPT system that can simultaneously perform two different types of outputs has become a hot topic of research; currently, traditional dual-load WPT systems have problems such as low space utilization, additional cross-coupling interference, the inability to achieve complete electrical isolation of the two output ports, and complex magnetic coupler design; therefore, it is a huge challenge to implement a constant current and constant voltage dual-type load WPT system. Summary of the invention

[0003] The present invention proposes a constant current and constant voltage dual-type load WPT system for AGV in order to solve the problems of low space utilization, additional cross-coupling, inability to achieve complete electrical isolation between the two output ports, and complex magnetic coupler design.

[0004] The technical solution of the present invention is achieved in this way:

[0005] A WPT system for AGV constant current and constant voltage dual-type loads, including a transmitting end Q coil L TA , transmitting end solenoid coil L TB 、Receiver Q coil L RA , receiving end solenoid coil L RB , transmitting end Q coil L TA Horizontally stacked on the transmitter ferrite, the transmitter solenoid coil L TB Wrapped around the transmitting end Q coil L TA The transmitting end ferrite forms a transmitting end charging plate; the receiving end Q coil L RA Horizontally stacked on the receiving end ferrite, the receiving end solenoid coil L RB Wrapped around the receiving end Q coil L RA The receiving end charging plate is formed on the receiving end ferrite; the transmitting end charging plate and the receiving end charging plate are placed horizontally and directly opposite to each other to form a system compact decoupling magnetic coupler, and the transmitting end Q coil L TA , transmitting end solenoid coil L TB Constitute two transmitting ends, the receiving end Q coil L RA , receiving end solenoid coil L RB Constitute two receiving ends, the transmitting end Q coil LTA With the receiving end Q coil L RA There is mutual inductance M1 between the transmitting end solenoid coil L TB With the receiving end solenoid coil L RB There is mutual inductance M2 between them.

[0006] Furthermore, the transmitting end Q coil L TA With the transmitting end solenoid coil L TB The mutual inductance M6 is zero; the transmitting end Q coil L TA With the receiving end solenoid coil L RB The mutual inductance M3 between them is zero; the transmitting end solenoid coil L TB With the receiving end Q coil L RA The mutual inductance M5 is zero; the solenoid coil L at the receiving end RB and the receiving end Q coil L RA The mutual inductance M4 is zero.

[0007] Furthermore, the transmitting end Q coil L TA One end is connected to the transmitter series compensation capacitor C st Connect compensation capacitor C in parallel with the transmitter pt2 The transmitter end is connected in series with a compensation capacitor C st The other end is connected to the transmitting end solenoid coil L TB One end of the transmitting end solenoid coil L TB The other end is connected to the transmitter in parallel with the compensation capacitor C pt1 The other end, the transmitting end Q coil L TA The other end is connected to the transmitter series compensation inductor L st Connect compensation capacitor C in parallel with the transmitter pt1 , transmitter series compensation inductor L st The other end is connected to one end of the high-frequency inverter H, and the other end of the high-frequency inverter H is connected to the transmitter parallel compensation capacitor C pt1 , transmitter parallel compensation capacitor C pt2 and the transmitting end solenoid coil L TB , the two ends of the high-frequency inverter H are connected to a DC voltage source U for power supply DC .

[0008] Furthermore, the receiving end Q coil L RA One end is connected to the first stage receiving end series compensation capacitor C srA One end of the first stage receiving end is connected in series with compensation capacitor C srA The other end is connected to the first stage receiving end rectifier D A One end of the input; the first stage receiving end rectifier D A The other end of the input is connected to the receiving end Q coil L RA The other end of the first-stage filter capacitor CfA and the first stage load resistor R LA Connect in parallel to the first-stage receiving rectifier D A output at both ends.

[0009] Furthermore, the receiving end solenoid coil L RB One end is connected to the second stage receiving end series compensation capacitor C srB One end of the second stage receiving end is connected in series with compensation capacitor C srB The other end is connected to the second stage receiving end rectifier D B The second-stage receiving end rectifier D B The other end of the input is connected to the receiving end spiral tube coil L RB The other end of the second-stage filter capacitor C fB and the second stage load resistor R LB Connect in parallel to the rectifier D at the second receiving end B output at both ends.

[0010] Furthermore, the resonance relationship of each compensation capacitor in the present invention is determined by the following equation:

[0011]

[0012] Where ω is the operating angular frequency of the system.

[0013] Furthermore, the receiving end Q coil L RA With the transmitting end Q coil L TA The voltage gain E of the first-stage receiving end formed by mutual inductance A , receiving end solenoid coil L RB With the transmitting end solenoid coil L TB The transconductance gain G of the second-stage receiving end formed by mutual inductance B Determined according to the following equation:

[0014]

[0015] Among them, M1 is the transmitting end coil L TA and the receiving coil L RA The mutual inductance of M2 is the transmitting coil L. TB and the receiving coil L RB The mutual inductance of st is the size of the transmitter series compensation inductor, L TA It is the self-inductance of the Q coil at the transmitting end.

[0016] By adopting the above technical solution, the beneficial effects of the present invention are as follows:

[0017] 1. Transmitter Q coil L TAHorizontally stacked on the transmitter ferrite, the transmitter solenoid coil L TB Wrapped around the transmitting end Q coil L TA The transmitting end ferrite forms a transmitting end charging plate; the receiving end Q coil L RA Horizontally stacked on the receiving end ferrite, the receiving end solenoid coil L RB Wrapped around the receiving end Q coil L RA The receiving end charging plate is formed on the receiving end ferrite; the transmitting end charging plate and the receiving end charging plate are placed horizontally and directly opposite to each other to form a compact decoupling magnetic coupler; the magnetic coupler does not have additional cross-coupling, which simplifies the system design and improves the compactness of the system;

[0018] 2. The system consists of two transmitting ends and two receiving ends. Both receiving ends are composed of S-type compensation topology, which reduces the system design cost and provides load-independent constant current output and constant voltage output for different power modules in AVG.

[0019] 3. Compared with the traditional dual-load WPT system, the compact decoupling magnetic coupler of the present invention has a solenoid coil wound around the Q coil, and the two coils are naturally decoupled. There is no additional cross-coupling between the transmitter charging disk and the receiver charging disk. The special structure of the magnetic coupler improves the space utilization of the system while reducing the complexity of the design;

[0020] 4. Compared with the same type of dual-load WPT system, the receiving end of the present invention adopts S-type compensation topology, which greatly reduces the number of compensation components and reduces the system design cost. The two output ports have electrical isolation characteristics, which is more suitable for AGV applications. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. 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.

[0022] Figure 1 It is a system architecture diagram of the present invention;

[0023] Figure 2 is an equivalent circuit diagram of the present invention;

[0024] Figure 3 It is a schematic diagram of the structure of the compact decoupling magnetic coupler of the present invention. DETAILED DESCRIPTION

[0025] 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.

[0026] like Figure 3 As shown, a WPT system for AGV constant current and constant voltage dual-type loads includes a transmitting end Q coil L TA , transmitting end solenoid coil L TB 、Receiver Q coil L RA , receiving end solenoid coil L RB , transmitting end Q coil L TA Horizontally stacked on the transmitter ferrite, the transmitter solenoid coil L TB Wrapped around the transmitting end Q coil L TA The transmitting end ferrite forms a transmitting end charging plate; the receiving end Q coil L RA Horizontally stacked on the receiving end ferrite, the receiving end solenoid coil L RB Wrapped around the receiving end Q coil L RA The receiving end charging plate is formed on the receiving end ferrite; the transmitting end charging plate and the receiving end charging plate are placed horizontally and directly opposite to each other to form a system compact decoupling magnetic coupler, and the transmitting end Q coil L TA , transmitting end solenoid coil L TB Constitute two transmitting ends, the receiving end Q coil L RA , receiving end solenoid coil L RB The transmitting end Q coil L constitutes two receiving ends. TA With the transmitting end solenoid coil L TB The mutual inductance M6 is zero; the transmitting end Q coil L TA With the receiving end solenoid coil L RB The mutual inductance M3 between them is zero; the transmitting end solenoid coil L TB With the receiving end Q coil L RA The mutual inductance M5 is zero; the solenoid coil L at the receiving end RB and the receiving end Q coil L RA The mutual inductance M4 is zero; the transmitting end Q coil L TA With the receiving end Q coil L RA There is mutual inductance M1 between the transmitting end solenoid coil L TB With the receiving end solenoid coil L RB There is mutual inductance M2 between them, and the special magnetic coupler structure eliminates additional cross-coupling interference, improving system efficiency while also improving system compactness.

[0027] like Figure 1 As shown, a WPT system for AGV constant current and constant voltage dual-type loads also includes a DC voltage source U DC , high frequency inverter H, first stage receiving end rectifier D A , the second stage receiving end rectifier D B , transmitter series compensation inductor L st , transmitter parallel compensation capacitor C pt2 , transmitter parallel compensation capacitor C pt1 , transmitter series compensation capacitor C st 、The first stage receiving end is connected in series with compensation capacitor C srA 、The second-stage receiving end is connected in series with the compensation capacitor C srB , the first filter capacitor C fA , the second filter capacitor C fB , the first load resistance R LA , the second load resistance R LB ; The transmitting end Q coil L TA One end is connected to the transmitter series compensation capacitor C st Connect compensation capacitor C in parallel with the transmitter pt2 The transmitter end is connected in series with a compensation capacitor C st The other end is connected to the transmitting end solenoid coil L TB One end of the transmitting end solenoid coil L TB The other end is connected to the transmitter in parallel with the compensation capacitor C pt1 The other end, the transmitting end Q coil L TA The other end is connected to the transmitter series compensation inductor L st Connect compensation capacitor C in parallel with the transmitter pt1 , transmitter series compensation inductor L st The other end is connected to one end of the high-frequency inverter H, and the other end of the high-frequency inverter H is connected to the transmitter parallel compensation capacitor C pt1 , transmitter parallel compensation capacitor C pt2 and the transmitting end solenoid coil L TB , the two ends of the high-frequency inverter H are connected to a DC voltage source U for power supply DC .

[0028] In this embodiment, the receiving end Q coil L RA One end is connected to the first stage receiving end series compensation capacitor C srA One end of the first stage receiving end is connected in series with compensation capacitor C srA The other end is connected to the first stage receiving end rectifier D A One end of the input; the first stage receiving end rectifier D A The other end of the input is connected to the receiving end Q coil L RA The other end of the first-stage filter capacitor C fAand the first stage load resistor R LA Connect in parallel to the first-stage receiving rectifier D A output at both ends.

[0029] In this embodiment, the receiving end solenoid coil L RB One end is connected to the second stage receiving end series compensation capacitor C srB One end of the second stage receiving end is connected in series with compensation capacitor C srB The other end is connected to the second stage receiving end rectifier D B The second-stage receiving end rectifier D B The other end of the input is connected to the receiving end spiral tube coil L RB The other end of the second-stage filter capacitor C fB and the second stage load resistor R LB Connect in parallel to the rectifier D at the second receiving end B output at both ends.

[0030] Figure 2 is the equivalent circuit diagram of the present invention, wherein, for the output voltage U of the full-bridge inverter I With DC voltage source supply voltage U DC The mathematical relationship between them can be expressed as follows:

[0031]

[0032] The output voltage U of the first stage receiving end A and the first-stage receiving rectifier input voltage U OA The relationship between the second-stage receiving end output voltage U B And the input voltage U of the second-stage receiving rectifier OB The relationship can be expressed as follows:

[0033]

[0034] In order to achieve the ZPA condition in the proposed system, the two output ports can simultaneously achieve load-independent constant current output and constant voltage output, and the resonant relationship of the compensation network can be expressed as follows:

[0035]

[0036] Where ω is the system operating angular frequency, C st The transmitter is connected in series with the compensation capacitor, C pt1 , C pt2 is the parallel compensation capacitor at the transmitter, L st The transmitter series compensation inductor, C srA The first-stage receiving end is connected in series with the compensation capacitor, C srB The second-stage receiving end is connected in series with the compensation capacitor, L TA, L TB is the self-inductance of the transmitting coil, L RA is the self-inductance of the first-stage receiving coil, L RB is the self-inductance of the second-stage receiving coil;

[0037] According to Kirchhoff's voltage law, the resonant condition of the system compensation network and ignoring the cross coupling M3, M4, M5, M6, the output current I of the high-frequency inverter H of this system is I 、First stage receiving end rectifier D A The input current I OA , the second stage receiving end rectifier D B The input current I OB It can be expressed as:

[0038]

[0039] Among them, M1 is the transmitting end coil L TA and the first-stage receiving coil L RA The mutual inductance of M2 is the transmitting coil L. TB and the second-stage receiving coil L RB Mutual inductance, R EA Indicates the equivalent resistance of the AC side corresponding to the first-stage receiving end, R EB Indicates the equivalent resistance of the AC side corresponding to the second-stage receiving end;

[0040] According to equation (4), the voltage gain E of the first-stage receiver is A , the transconductance gain of the second-stage receiving end G B It can be expressed as:

[0041]

[0042] According to the voltage gain E of the first-stage receiving end A and the transconductance gain G of the second-stage receiver B It can be seen that the output voltage gain of the first-stage receiving end and the transconductance gain of the second-stage receiving end are both independent of the corresponding equivalent resistance. Therefore, the system can simultaneously achieve load-independent constant current output and constant voltage output;

[0043] In addition, the system input impedance Z in It can be derived from equation (4) as follows:

[0044]

[0045] It can be seen from equation (6) that the system input impedance is purely resistive. The system realizes ZPA operation, eliminates the system's reactive circulating current, and improves the system transmission efficiency.

[0046] Components not described in detail herein are prior art.

[0047] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A WPT system for AGV constant current and constant voltage dual-type loads, characterized by: Including the transmitter Q coil L TA , transmitting end solenoid coil L TB 、Receiver Q coil L RA , receiving end solenoid coil L RB , transmitting end Q coil L TA Horizontally stacked on the transmitter ferrite, the transmitter solenoid coil L TB Wrapped around the transmitting end Q coil L TA The transmitting end ferrite forms a transmitting end charging plate; the receiving end Q coil L RA Horizontally stacked on the receiving end ferrite, the receiving end solenoid coil L RB Wrapped around the receiving end Q coil L RA The receiving end charging plate is formed on the receiving end ferrite; the transmitting end charging plate and the receiving end charging plate are placed horizontally and directly opposite to each other to form a system compact decoupling magnetic coupler, and the transmitting end Q coil L TA , transmitting end solenoid coil L TB Constitute two transmitting ends, the receiving end Q coil L RA , receiving end solenoid coil L RB Constitute two receiving ends, the transmitting end Q coil L TA With the receiving end Q coil L RA There is mutual inductance M1 between the transmitting end solenoid coil L TB With the receiving end solenoid coil L RB There is mutual inductance M2 between them.

2. According to claim 1, a WPT system for AGV constant current and constant voltage dual-type loads, characterized in that: The transmitting end Q coil L TA With the transmitting end solenoid coil L TB The mutual inductance M6 is zero; the transmitting end Q coil L TA With the receiving end solenoid coil L RB The mutual inductance M3 between them is zero; the transmitting end solenoid coil L TB With the receiving end Q coil L RA The mutual inductance M5 is zero; the solenoid coil L at the receiving end RB and the receiving end Q coil L RA The mutual inductance M4 is zero.

3. According to claim 2, a WPT system for AGV constant current and constant voltage dual-type loads, characterized in that: The transmitting end Q coil L TA One end is connected to the transmitter series compensation capacitor C st Connect compensation capacitor C in parallel with the transmitter pt2 The transmitter end is connected in series with a compensation capacitor C st The other end is connected to the transmitting end solenoid coil L TB One end of the transmitting end solenoid coil L TB The other end is connected to the transmitter in parallel with the compensation capacitor C pt1 The other end, the transmitting end Q coil L TA The other end is connected to the transmitter series compensation inductor L st Connect compensation capacitor C in parallel with the transmitter pt1 , transmitter series compensation inductor L st The other end is connected to one end of the high-frequency inverter H, and the other end of the high-frequency inverter H is connected to the transmitter parallel compensation capacitor C pt1 , transmitter parallel compensation capacitor C pt2 and the transmitting end solenoid coil L TB , the two ends of the high-frequency inverter H are connected to a DC voltage source U for power supply DC .

4. According to claim 3, a WPT system for AGV constant current and constant voltage dual-type loads is characterized in that: Receiving end Q coil L RA One end is connected to the first stage receiving end series compensation capacitor C srA One end of the first stage receiving end is connected in series with compensation capacitor C srA The other end is connected to the first stage receiving end rectifier D A One end of the input; the first stage receiving end rectifier D A The other end of the input is connected to the receiving end Q coil L RA The other end of the first-stage filter capacitor C fA and the first stage load resistor R LA Connect in parallel to the first-stage receiving rectifier D A output at both ends.

5. According to claim 4, a WPT system for AGV constant current and constant voltage dual-type loads, characterized in that: Receiving end solenoid coil L RB One end is connected to the second stage receiving end series compensation capacitor C srB One end of the second stage receiving end is connected in series with compensation capacitor C srB The other end is connected to the second stage receiving end rectifier D B The second-stage receiving end rectifier D B The other end of the input is connected to the receiving end spiral tube coil L RB The other end of the second-stage filter capacitor C fB and the second stage load resistor R LB Connect in parallel to the rectifier D at the second receiving end B output at both ends.

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