MC-WPT system based on transmitting terminal mode switching and mode switching method thereof

Abstract

The invention relates to the technical field of wireless power transmission, and particularly discloses an MC-WPT system based on transmitting end mode switching and a mode switching method thereof, and the MC-WPT system is provided with a mode switching inverter composed of switching tubes S1 to S6 and a primary side resonance network composed of a switching tube S7, a capacitor Crp, a capacitor Cp and a primary side compensation inductor Lrp. The mode switching inverter and the primary side resonance network are specifically connected, and the switching time sequence states of switching tubes S1-S7 are controlled, so that the mode switching inverter is switched between full-bridge inversion and half-bridge inversion, and the primary side resonance network is switched between a constant-current output LCC type compensation network and a constant-voltage output S type compensation network; therefore, the system is controlled to be switched among a constant-current output full-bridge inversion mode, a constant-current output half-bridge inversion mode, a constant-voltage output full-bridge inversion mode and a constant-voltage output half-bridge inversion mode. According to the invention, fewer devices are added, the control is simple, and different application requirements can be met.

Description

Technical Field

[0001] The present invention relates to the technical field of wireless power transmission, and in particular to a MC-WPT system based on transmitter mode switching and a mode switching method thereof. Background Art

[0002] The magnetically coupled wireless power transfer (MC-WPT) system has the advantages of safety, flexibility and convenience, and is widely used in electric vehicles, self-guided robots, drone equipment and other fields.

[0003] Magnetic coupling wireless charging usually needs to switch under constant current and constant voltage output characteristics, which is conducive to improving battery life and efficient charging. Most traditional magnetic coupling wireless constant voltage and constant current charging methods use specific compensation topologies. Specific compensation topology is a compensation topology that combines two different output characteristics. It needs to rely on multiple switch tubes and multiple capacitors to switch between two LCC-LCC and S-LCC compensation topologies with different output characteristics. For example, the utility model patent "A wireless power transmission device based on composite LCC compensation" with authorization announcement number CN212063636U sets three switch tubes, three capacitors and one inductor, and controls the on-off of the three switch tubes to control the primary compensation network to switch between S-type and LCC-type networks. However, these hybrid topologies do not combine circuit characteristics, and the number of components (switches, capacitors) is large, which will increase too many devices, increase control costs and circuit complexity.

[0004] In order to ensure the system power demand under heavy load conditions and improve the energy transmission efficiency of the system under light load conditions, the existing magnetic coupling wireless power transmission system switches the working mode of the inverter, using the full-bridge inverter mode under heavy load and the half-bridge inverter mode under light load. For example, the invention patent with the authorization announcement number CN112467891B "An IPT system efficiency optimization method based on full-bridge and half-bridge switching" discloses a relatively simple full-bridge and half-bridge switching method, which is achieved by switching the DC power supply U in Set capacitor C between the full-bridge inverter l1 , C l2 And the switch tube S realizes switching.

[0005] At present, there is a lack of an MC-WPT system that can realize both full-bridge and half-bridge inverters and constant current and constant voltage output. If the existing technologies are simply combined directly, such as combining the utility model patent "A wireless power transmission device based on composite LCC compensation" and the invention patent "An IPT system efficiency optimization method based on full-bridge and half-bridge switching", although full-bridge and half-bridge inverters and constant current and constant voltage outputs can be realized, too many devices are added, which increases the control cost and circuit complexity. Summary of the invention

[0006] The present invention provides a MC-WPT system based on transmitter mode switching and a mode switching method thereof, and solves the technical problem that there is currently a lack of an MC-WPT system that has fewer additional devices, simple control, can achieve both full-bridge and half-bridge inversion and constant current and voltage output.

[0007] In order to solve the above technical problems, the present invention provides a MC-WPT system based on transmitter mode switching, including a transmitter and a receiver, wherein the transmitter includes a DC input voltage source U DC , mode switching inverter, primary resonant network and transmitting coil L p , the receiving end includes a receiving coil L s , secondary side resonant network, rectifier circuit, output filter capacitor C o and equivalent load R L ;

[0008] The mode switching inverter is composed of switch tubes S1 to S6. The switch tubes S1 and S2 are connected in series in sequence to the DC input voltage source U DC The first bridge arm between the positive and negative electrodes, the switch tubes S3 and S4 are connected in series in sequence to the DC input voltage source U DC The second bridge arm between the positive and negative electrodes, the switch tubes S5 and S6 are connected in series in sequence to the DC input voltage source U DC The third bridge arm between the positive and negative electrodes;

[0009] The primary resonant network includes a midpoint of the first bridge arm and a transmitting coil L connected in series in sequence. p The capacitance C between the two ends rp and capacitor C p , and connected in series with the midpoint of the third bridge arm and the capacitor C rp With capacitor C p The common terminal between the switch tube S7 and the primary compensation inductor L rp , transmitting coil L p The other end of the bridge is connected to the midpoint of the second bridge arm;

[0010] By controlling the switching timing state of the switch tubes S1 to S7, the mode switching inverter is controlled to switch between full-bridge inverter and half-bridge inverter, and the primary resonant network is controlled by the capacitor C rp , capacitor C p , primary compensation inductor L rp The constant current output LCC compensation network formed by connecting the capacitor C rp , capacitor C p The constant voltage output S-type compensation network is switched in series, so that the control system switches between constant current output full-bridge inverter mode, constant current output half-bridge inverter mode, constant voltage output full-bridge inverter mode and constant voltage output half-bridge inverter mode.

[0011] Preferably, the switch tube S7 is controlled to be in a constant on state, so that the primary resonant network is a constant current output LCC type compensation network; the switch tube S7 is controlled to be in a constant off state, so that the primary resonant network is a constant voltage output S type compensation network.

[0012] Preferably, when the switch tube S7 is in a constant conduction state, by controlling the switching timing states of the switch tubes S1 to S6, the mode switching inverter is equivalent to a full-bridge inverter connected to the constant current output LCC type compensation network, and the control system switches to the constant current output full-bridge inverter mode.

[0013] Preferably, when the switch tube S7 is in a constant conduction state, by controlling the switching timing states of the switch tubes S1 to S6, the mode switching inverter is equivalent to a half-bridge inverter connected to the constant current output LCC type compensation network, and the control system switches to the constant current output half-bridge inverter mode.

[0014] Preferably, when the switch tube S7 is in a constant off state, by controlling the switching timing states of the switch tubes S1 to S6, the mode switching inverter is equivalent to a full-bridge inverter connected to the constant voltage output S-type compensation network, and the control system switches to the constant voltage output full-bridge inverter mode.

[0015] Preferably, when the switch tube S7 is in a constant off state, by controlling the switching timing states of the switch tubes S1 to S6, the mode switching inverter is equivalent to a half-bridge inverter connected to the constant voltage output S-type compensation network, and the control system switches to the constant voltage output half-bridge inverter mode.

[0016] Preferably, the switch timing states of the switch tubes S1 to S7 are represented by Lead, Lag, 1, and 0, where Lead indicates that the switch tube is in a switch state and the phase is a leading phase, Lag indicates that the switch tube is in a switch state and the phase is a lagging phase, 1 indicates that the switch tube is in a constant on state, and 0 indicates that the switch tube is in a constant off state;

[0017] The switch timing states of the control switch tubes S1 to S7 are respectively Lead, Lag, Lead, Lag, Lag, Lead, 1, and the control system is switched to the constant current output full-bridge inverter mode, and at this time, the switch tubes S1 and S3 are synchronized, and the switch tubes S2 and S4 are synchronized;

[0018] The switch timing states of the control switches S1 to S7 are respectively 0, 1, 0, 1, Lag, Lead, 1 and the control system is switched to the constant current output half-bridge inverter mode, and at this time the switch tubes S1 and S3 are synchronized, and the switch tubes S2 and S4 are synchronized;

[0019] The switch timing states of the control switch tubes S1 to S7 are respectively Lead, Lag, Lag, Lead, 0, 0, 0, and the control system is switched to the constant voltage output full-bridge inverter mode, and at this time, the switch tubes S1 and S4 are synchronized, and the switch tubes S2 and S3 are synchronized;

[0020] The switch timing states of the control switches S1 to S7 are Lead, Lag, 0, 1, 0, 0, 0 respectively, and the control system is switched to the constant voltage output half-bridge inverter mode.

[0021] Preferably, the transmitting coil L p , capacitor C rp and capacitor C p Satisfaction relationship ω represents the operating angular frequency of the system.

[0022] Preferably, the secondary side resonant network adopts an LCC type compensation network.

[0023] The present invention also provides a mode switching method of an MC-WPT system based on transmitter mode switching, the key of which is that it includes the steps of: controlling the switching timing states of switch tubes S1 to S7 according to application requirements, thereby controlling the system to switch between constant current output full-bridge inverter mode, constant current output half-bridge inverter mode, constant voltage output full-bridge inverter mode and constant voltage output half-bridge inverter mode.

[0024] The MC-WPT system based on transmitter mode switching and the mode switching method thereof provided by the present invention are provided with a mode switching inverter composed of switch tubes S1 to S6 and a switch tube S7, a capacitor C rp , capacitor C p , primary compensation inductor L rp The primary resonant network is composed of a mode switching inverter and a primary resonant network, and the mode switching inverter is switched between full-bridge inverter and half-bridge inverter by specifically connecting the mode switching inverter and the primary resonant network and controlling the switch timing state of the switch tubes S1 to S7, and the primary resonant network is switched between the constant current output LCC type compensation network and the constant voltage output S type compensation network, so that the control system switches between the constant current output full-bridge inverter mode, the constant current output half-bridge inverter mode, the constant voltage output full-bridge inverter mode and the constant voltage output half-bridge inverter mode. Compared with the general LCC-LCC type WPT system, the present invention controls the system to switch between four modes by adding three switch tubes and controlling the switch timing state of a total of 7 switch tubes, with fewer added devices and simple control, which can meet different application requirements. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 is a circuit diagram of a MC-WPT system based on transmitter mode switching provided by an embodiment of the present invention;

[0026] Figure 2 is an equivalent circuit diagram of the transmitter under the constant current output full-bridge inverter mode provided by an embodiment of the present invention;

[0027] Figure 3 is a system equivalent circuit diagram under a constant current output full-bridge inverter mode provided by an embodiment of the present invention;

[0028] Figure 4 is an equivalent circuit diagram of the transmitter under the constant current output half-bridge inverter mode provided by an embodiment of the present invention;

[0029] Figure 5 is a system equivalent circuit diagram under a constant current output half-bridge inverter mode provided by an embodiment of the present invention;

[0030] Figure 6 is an equivalent circuit diagram of the transmitter under the constant voltage output full-bridge inverter mode provided by an embodiment of the present invention;

[0031] Figure 7 is a system equivalent circuit diagram under a constant voltage output full-bridge inverter mode provided by an embodiment of the present invention;

[0032] Figure 8 is an equivalent circuit diagram of the transmitter under the constant voltage output half-bridge inverter mode provided by an embodiment of the present invention;

[0033] Fig. 9 It is a system equivalent circuit diagram under the constant voltage output half-bridge inverter mode provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0034] The following specifically illustrates the implementation mode of the present invention in conjunction with the accompanying drawings. The embodiments are provided for illustrative purposes only and cannot be understood as limiting the present invention. The accompanying drawings are provided for reference and illustration only and do not constitute a limitation on the scope of patent protection of the present invention, because many changes can be made to the present invention without departing from the spirit and scope of the present invention.

[0035] Transmitter coil L of S-LCC compensation network p Only through a series compensation capacitor C p The two are in the same resonant branch and belong to a series resonant relationship. p The series compensation capacitor C p And parallel compensation capacitor C rp For compensation, the three are in the same resonant circuit, which is also a series resonant relationship. By making a distinction at the corner mark, the parameter requirements for the compensation capacitor of the S-LCC compensation network and the LCC-LCC compensation network are as follows:

[0036]

[0037] Where ω represents the operating angular frequency of the system.

[0038] It can be seen that at the system operating frequency and the transmitting coil L p Under the condition of unchanged, the compensation capacitor C of LCC-LCC compensation network p_LCC-LCC and C rp_LCC-LCC The series equivalent capacitance value and the compensation capacitance C of the S-LCC compensation network p_S-LCC The values ​​are equal, which means that when the resonance condition is met, it is only necessary to change the primary compensation inductance L of the LCC-LCC compensation network. rp_LCC-LCC Disconnect and connect the parallel compensation capacitor C rp_LCC-LCC Connect to inverter output and transmitting coil L p The resonant branch where it is located can realize the conversion to the S-LCC type compensation network. In order to realize the switching of full-bridge and half-bridge inverters at the same time, add fewer devices, and simply realize the control of mode switching, the embodiment of the present invention realizes the switching of full-bridge and half-bridge inverters and constant current and constant voltage output by adding three switch tubes and controlling these three switch tubes, so that the system has four working modes, namely, constant current output full-bridge inverter mode, constant current output half-bridge inverter mode, constant voltage output full-bridge inverter mode and constant voltage output half-bridge inverter mode.

[0039] Specifically, the MC-WPT system based on transmitter mode switching provided in the embodiment of the present invention is as follows: Figure 1 As shown in the circuit diagram, it includes a transmitting end and a receiving end. The transmitting end includes a DC input voltage source U DC , mode switching inverter, primary resonant network and transmitting coil L p , the receiving end includes a receiving coil L s , secondary side resonant network, rectifier circuit (full bridge rectifier formed by connecting diodes D1-D4), output filter capacitor C o and equivalent load R L (Car battery, etc.).

[0040] like Figure 1 As shown, the mode switching inverter is composed of switch tubes S1 to S6 (MOSFET), wherein the switch tubes S1 and S2 are connected in series in sequence to the DC input voltage source U DC The first bridge arm between the positive and negative electrodes, the switch tubes S3 and S4 are connected in series in sequence to the DC input voltage source U DC The second bridge arm between the positive and negative electrodes, the switch tubes S5 and S6 are connected in series in sequence to the DC input voltage source U DC The third bridge arm between the positive and negative poles.

[0041] like Figure 1As shown, the primary resonant network includes a midpoint of the first bridge arm and a transmitting coil L connected in series in sequence. p The capacitance C between the two ends rp and capacitor C p , and connected in series with the midpoint of the third bridge arm and capacitor C rp With capacitor C p The bidirectional switch tube S7 (composed of two MOSFETs connected in reverse series) between the common terminals and the primary compensation inductor L rp , transmitting coil L p The other end is connected to the midpoint of the second bridge arm.

[0042] like Figure 1 As shown, the secondary side resonant network adopts a standard LCC network structure, including a secondary side series compensation capacitor C s , secondary side parallel compensation capacitor C rs and the secondary compensation inductor L rs .u a 、u b 、u c Respectively represent the output voltage of the midpoint of the three bridge arms of the inverter bridge, i rp is the primary compensation inductance L rp The current on p with i s is the transmitting coil L p With receiving coil L s The current on rs is the secondary compensation inductor L rs The current on o is the output voltage of the secondary resonant network, i L and u L are the system output current and output voltage.

[0043] Compared with the general LCC-LCC type WPT system, Figure 1 The MC-WPT system based on transmitter mode switching shown in the figure only adds three switch tubes, and a total of seven switch tubes S1~S7 are set. By controlling the switching timing state of the switch tubes S1~S7, the mode switching inverter can be switched between the full-bridge and half-bridge inverters, and the primary side resonant network can be switched between the LCC type compensation network for realizing constant current output and the S type compensation network for realizing constant voltage output, so as to realize the capacitor C in the constant current mode. rp The parallel compensation capacitor that constitutes the primary side resonant network has a capacitance C in constant voltage mode. rp With capacitor C p Together with the series compensation capacitors forming the primary side resonant network, the control system switches between a constant current output full-bridge inverter mode, a constant current output half-bridge inverter mode, a constant voltage output full-bridge inverter mode and a constant voltage output half-bridge inverter mode.

[0044] In order to facilitate the description of the switching timing state, the four types of switching timing states of the switch tubes S1 to S7 are represented by Lead, Lag, 1, and 0. Lead indicates that the switch tube is in the switching state and the phase is the leading phase, Lag indicates that the switch tube is in the switching state and the phase is the lagging phase, 1 indicates that the switch tube is in the constant on state, and 0 indicates that the switch tube is in the constant off state. By controlling the switching timing states of the switch tubes S1 to S7, the system can work in full-bridge inverter and half-bridge inverter modes under constant current output, and full-bridge inverter and half-bridge inverter modes under constant voltage output. Next, these four output modes are constructed and analyzed respectively.

[0045] In order to make the system have constant current output characteristics, it is necessary to keep the switch tube S7 open to reduce the primary compensation inductance L rp The system is put into use to build an LCC-LCC compensation network with constant current output characteristics. In the constant current output mode, by controlling the state and timing of the switch tubes S1~S6, the system can also work in the constant current full-bridge inverter mode and the constant current half-bridge inverter mode respectively. Next, the constant current full-bridge inverter mode and the constant current half-bridge inverter mode are constructed and analyzed respectively.

[0046] (1) Constant current output full-bridge inverter mode

[0047] In order to realize the constant current output and primary full-bridge inverter function of the system, the switch timing states of the switch tubes S1 to S7 are set as shown in Table 1.

[0048] Table 1 Switching timing state table of switch tubes S1~S7 in constant current output full-bridge inverter mode

[0049]

[0050] It can be seen from Table 1 that when the system operates in the constant current output full-bridge inverter mode, the switch tubes S1, S3, and S6 all operate in the leading Lead state, the switch tubes S2, S4, and S5 all operate in the lagging Lag state, and the switch tube S7 is in the constant conduction state. At this time, the switch tubes S1 and S3 are synchronized, and the switch tubes S2 and S4 are synchronized. At this time, the equivalent diagram of the transmitter is as follows Figure 2 shown.

[0051] from Figure 2 It can be seen that at this time, the switch tubes S1 and S3 are equivalent to the state of two tubes in parallel, and the switch tubes S2 and S4 are equivalent to the state of two tubes in parallel. For the convenience of analysis, the two upper bridge arms where the switch tubes S1 and S3 are located are simplified into one upper bridge arm, and the switch tube S 13 Similarly, switch tubes S2 and S4 are connected in parallel and then the switch tube S 24 Indicates that the branch where the switch tube S7 is located is replaced by a wire, and there is u a =u b , that is uab Constantly 0, capacitance C rp Equivalent to connecting in parallel with capacitor C p and inductor L p At both ends, the system resonant network parameters satisfy equation (1). At this time, by controlling the state and timing of the switch tubes S1-S7, the full-bridge inverter LCC-LCC constant current topology is constructed, and the system equivalent circuit under the constant current output full-bridge inverter mode is obtained as follows: Figure 3 shown.

[0052] (2) Constant current output half-bridge inverter mode

[0053] In order to realize the half-bridge inverter output of the primary side of the system in the constant current output mode, the switch timing states of the switch tubes S1-S7 are set as shown in Table 2.

[0054] Table 2 Switching timing state table of switch tubes S1~S7 in constant current output half-bridge inverter mode

[0055]

[0056] It can be seen from Table 2 that when the system operates in the constant current output mode of the half-bridge inverter, the switch tubes S1 and S3 are kept in the off state, the switch tubes S2 and S4 are kept in the on state, and the switch tube S5 operates in the lagging Lag state, and the switch tube S6 operates in the leading Lead state. Like the constant current output mode of the full-bridge inverter, at this time, the switch tubes S1 and S3 are still synchronized, and the switch tubes S2 and S4 are synchronized, so u ab Still always equal to 0, the equivalent circuit of the transmitter is as follows Figure 4 shown.

[0057] For the convenience of analysis, the switch tube S 13 Ignore the branch where it is located, switch tube S 24 The branch is replaced by a wire. At this time, the construction of the half-bridge inverter LCC-LCC constant current topology is realized by controlling the state and timing of the switch tubes S1-S7, and the system equivalent circuit under the constant current output half-bridge inverter mode is obtained as follows Figure 5 shown.

[0058] In order to make the system have a constant voltage output characteristic, the switch tube S7 needs to be kept off to compensate the inductor L rp Cut out from the system and construct an S-LCC compensation network with constant voltage output characteristics. In the constant voltage output mode, by controlling the state and timing of the switch tubes S1~S6, the system can also work in the constant voltage output full-bridge inverter mode and the constant voltage output half-bridge inverter mode respectively. Next, the constant voltage output full-bridge inverter mode and the constant voltage output half-bridge inverter mode are constructed and analyzed respectively.

[0059] (3) Constant voltage output full-bridge inverter mode

[0060] In order to realize the constant voltage output of the system and the primary side full-bridge inverter function, the switch timing states are set for the switch tubes S1 to S7 as shown in Table 3.

[0061] Table 3 Switching timing state table of switch tubes S1~S7 in constant voltage output full-bridge inverter mode

[0062]

[0063] It can be seen from Table 3 that when the system operates in the constant voltage output mode of the full-bridge inverter, the switch tubes S1 and S4 operate in the leading Lead state, the switch tubes S2 and S3 operate in the lagging Lag state, and the switch tubes S5, S6, and S7 are in the constant off state. At this time, the switch tubes S1 and S4 are synchronized, and the switch tubes S2 and S3 are synchronized. At this time, the equivalent circuit of the transmitter is as follows: Figure 6 shown.

[0064] from Figure 6 It can be seen that at this time, the switch tubes S5-S7 and the inductor L rp Not connected to the system, for the convenience of analysis, switch tubes S5-S7 and inductor L rp The branch where it is located is ignored, and the capacitor C rp With capacitor C p After connecting in series with the transmitting coil L p The primary resonant circuit of the S-LCC network is formed. The system resonant network parameters also satisfy equation (1). At this time, the construction of the full-bridge inverter S-LCC constant voltage topology is realized by controlling the state and timing of the switch tubes S1-S7. The system equivalent circuit under the constant voltage output full-bridge inverter mode is obtained as follows: Figure 7 shown.

[0065] (4) Constant voltage output half-bridge inverter mode

[0066] In order to realize the half-bridge inverter output of the primary side of the system in the constant voltage output mode, the switch timing states of the switch tubes S1-S7 are set as shown in Table 4.

[0067] Table 4 Switching timing status table of switch tubes S1~S7 in constant voltage output half-bridge inverter mode

[0068]

[0069] It can be seen from Table 4 that when the system operates in the constant voltage output half-bridge inverter mode, the switch tubes S3, S5-S7 are all kept in the off state, the switch tube S4 is kept in the on state, and the switch tube S1 operates in the leading Lead state, and the switch tube S2 operates in the lagging Lag state. At this time, the equivalent electrical diagram of the transmitter is as follows: Figure 8 shown.

[0070] For the convenience of analysis, the branch where the switch tube S3 is located is ignored, and the branch where the switch tube S4 is located is replaced by a wire. At this time, the construction of the half-bridge inverter S-LCC constant current topology is realized by controlling the state and timing of the switch tubes S1-S7, and the system equivalent circuit under the constant voltage output full-bridge inverter mode is obtained as follows Fig. 9 shown.

[0071] It should be noted that the control of the switching timing states of the switch tubes S1 to S7 is implemented through a controller, and the controller controls the switching timing states of the switch tubes S1 to S7 according to application requirements.

[0072] Based on the above system, the present invention also provides a mode switching method of the MC-WPT system based on the transmitter mode switching, including the steps of: controlling the switch timing state of the switch tubes S1 to S7 according to the application requirements, so as to control the system to switch between the constant current output full-bridge inverter mode, the constant current output half-bridge inverter mode, the constant voltage output full-bridge inverter mode and the constant voltage output half-bridge inverter mode. The specific control process has been described in the above system and will not be repeated in this method.

[0073] In summary, the MC-WPT system based on transmitter mode switching and the mode switching method thereof provided in the embodiment of the present invention are provided with a mode switching inverter composed of switch tubes S1 to S6 and a switch tube S7, a capacitor C rp , capacitor C p , primary compensation inductor L rp The primary resonant network is composed of a mode switching inverter and a primary resonant network, and the mode switching inverter is switched between full-bridge inverter and half-bridge inverter by specifically connecting the mode switching inverter and the primary resonant network and controlling the switch timing state of the switch tubes S1 to S7, and the primary resonant network is switched between the constant current output LCC type compensation network and the constant voltage output S type compensation network, so that the control system switches between the constant current output full-bridge inverter mode, the constant current output half-bridge inverter mode, the constant voltage output full-bridge inverter mode and the constant voltage output half-bridge inverter mode. Compared with the general LCC-LCC type WPT system, the present invention controls the system to switch between four modes by adding three switch tubes and controlling the switch timing state of a total of 7 switch tubes, with fewer added devices and simple control, which can meet different application requirements.

[0074] The above embodiments are preferred implementation modes of the present invention, but the implementation modes of the present invention are not limited to the above embodiments. Any other changes, modifications, substitutions, combinations, and simplifications that do not deviate from the spirit and principles of the present invention should be equivalent replacement methods and are included in the protection scope of the present invention.

Claims

1. The MC-WPT system based on transmitter mode switching is characterized by: It includes a transmitting end and a receiving end, wherein the transmitting end includes a DC input voltage source U DC , mode switching inverter, primary resonant network and transmitting coil L p , the receiving end includes a receiving coil L s , secondary side resonant network, rectifier circuit, output filter capacitor C o and equivalent load R L ; The mode switching inverter is composed of switch tubes S1 to S6. The switch tubes S1 and S2 are connected in series in sequence to the DC input voltage source U DC The first bridge arm between the positive and negative electrodes, the switch tubes S3 and S4 are connected in series in sequence to the DC input voltage source U DC The second bridge arm between the positive and negative electrodes, the switch tubes S5 and S6 are connected in series in sequence to the DC input voltage source U DC The third bridge arm between the positive and negative electrodes; The primary resonant network includes a midpoint of the first bridge arm and a transmitting coil L connected in series in sequence. p The capacitance C between the ends of rp and capacitor C p , and connected in series with the midpoint of the third bridge arm and the capacitor C rp With capacitor C p The common terminal between the switch tube S7 and the primary compensation inductor L rp , transmitting coil L p The other end of the bridge is connected to the midpoint of the second bridge arm; By controlling the switching timing state of the switch tubes S1 to S7, the mode switching inverter is controlled to switch between full-bridge inverter and half-bridge inverter, and the primary resonant network is controlled by the capacitor C rp , capacitor C p , primary compensation inductor L rp The constant current output LCC compensation network formed by connecting the capacitor C rp , capacitor C p The constant voltage output S-type compensation network is switched in series, so that the control system switches between constant current output full-bridge inverter mode, constant current output half-bridge inverter mode, constant voltage output full-bridge inverter mode and constant voltage output half-bridge inverter mode.

2. The MC-WPT system based on transmitter mode switching according to claim 1, characterized in that: The switch tube S7 is controlled to be in a constant on state, so that the primary resonant network is a constant current output LCC type compensation network; the switch tube S7 is controlled to be in a constant off state, so that the primary resonant network is a constant voltage output S type compensation network.

3. The MC-WPT system based on transmitter mode switching according to claim 2 is characterized in that: When the switch tube S7 is in a constant conduction state, by controlling the switching timing states of the switch tubes S1 to S6, the mode switching inverter is equivalent to a full-bridge inverter connected to the constant current output LCC type compensation network, and the control system switches to the constant current output full-bridge inverter mode.

4. The MC-WPT system based on transmitter mode switching according to claim 2, characterized in that: When the switch tube S7 is in a constant conduction state, by controlling the switching timing states of the switch tubes S1 to S6, the mode switching inverter is equivalent to a half-bridge inverter connected to the constant current output LCC type compensation network, and the control system switches to the constant current output half-bridge inverter mode.

5. The MC-WPT system based on transmitter mode switching according to claim 2, characterized in that: When the switch tube S7 is in a constant off state, by controlling the switching timing states of the switch tubes S1 to S6, the mode switching inverter is equivalent to a full-bridge inverter connected to the constant voltage output S-type compensation network, and the control system switches to the constant voltage output full-bridge inverter mode.

6. The MC-WPT system based on transmitter mode switching according to claim 2, characterized in that: When the switch tube S7 is in a constant off state, by controlling the switching timing states of the switch tubes S1 to S6, the mode switching inverter is equivalent to a half-bridge inverter connected to the constant voltage output S-type compensation network, and the control system switches to the constant voltage output half-bridge inverter mode.

7. The MC-WPT system based on transmitter mode switching according to any one of claims 1 to 6, characterized in that: The switching timing states of the switch tubes S1 to S7 are represented by Lead, Lag, 1, and 0. Lead indicates that the switch tube is in the switching state and the phase is the leading phase, Lag indicates that the switch tube is in the switching state and the phase is the lagging phase, 1 indicates that the switch tube is in the constant on state, and 0 indicates that the switch tube is in the constant off state. The switch timing states of the control switch tubes S1 to S7 are respectively Lead, Lag, Lead, Lag, Lag, Lead, 1, and the control system is switched to the constant current output full-bridge inverter mode, and at this time, the switch tubes S1 and S3 are synchronized, and the switch tubes S2 and S4 are synchronized; The switch timing states of the control switches S1 to S7 are respectively 0, 1, 0, 1, Lag, Lead, 1 and the control system is switched to the constant current output half-bridge inverter mode, and at this time the switch tubes S1 and S3 are synchronized, and the switch tubes S2 and S4 are synchronized; The switch timing states of the control switch tubes S1 to S7 are respectively Lead, Lag, Lag, Lead, 0, 0, 0, and the control system is switched to the constant voltage output full-bridge inverter mode, and at this time, the switch tubes S1 and S4 are synchronized, and the switch tubes S2 and S3 are synchronized; The switch timing states of the control switches S1 to S7 are Lead, Lag, 0, 1, 0, 0, 0 respectively, and the control system is switched to the constant voltage output half-bridge inverter mode.

8. The MC-WPT system based on transmitter mode switching according to any one of claims 1 to 6, characterized in that: The transmitting coil L p , capacitor C rp and capacitor C p Satisfaction relationship ω represents the operating angular frequency of the system.

9. The MC-WPT system based on transmitter mode switching according to claim 8, characterized in that: The secondary side resonant network adopts an LCC type compensation network.

10. The mode switching method of the MC-WPT system based on transmitter mode switching according to any one of claims 1 to 9, characterized in that: The invention comprises the steps of controlling the switching timing states of the switch tubes S1 to S7 according to the application requirements, thereby controlling the system to switch between a constant current output full-bridge inverter mode, a constant current output half-bridge inverter mode, a constant voltage output full-bridge inverter mode and a constant voltage output half-bridge inverter mode.

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