A composite half-bridge reconfigurable device and a wireless charging system based on the device

Abstract

The present invention discloses a composite half-bridge reconfigurable device and a wireless charging system based on the device, belonging to the field of wireless power transmission. The reconfigurable device is specifically connected to: a DC power supply E One end is connected to S 1 One end, DC power supply E The other end is connected to the c-phase terminal, S 3 One end and S 4 One end; S 1 The other end is connected to the a phase terminal, the A phase output terminal and the S 2 One end; S 2 The other end is connected to the b-phase terminal and the first compensator P 1 One end and S 3 The other end: the first compensator P 1 The other end is connected to the second compensator P 2 One end and the third compensator P 3 One end; S 4 The other end is connected to the second compensator P 2 The other end; the third compensator P 3 The other end is connected to the B phase output end; two wireless charging systems based on the device are also provided. The present invention uses a small number of switches, enhances the smoothness and rapidity of system mode switching, has configurable output constant current value and constant voltage value independent of the coupling mechanism, and expands the application range of the coupling mechanism.

Description

Technical Field

[0001] The present invention relates to the technical field of wireless power transmission, in particular to a composite half-bridge reconfigurable device and a wireless charging system based on the device. Background Art

[0002] Wireless power transmission technology is a non-contact way of transmitting electric energy. It is flexible in charging, highly adaptable to the environment, safe and reliable, and can avoid the safety issues such as sparks and leakage in traditional contact power transmission systems. The main transmission modes of this technology include electromagnetic induction coupling, magnetic resonance coupling and electric field coupling. At present, this technology is widely used in electric vehicles, drones, medical electronics and portable electronic products, etc., with wide applications and great development potential.

[0003] In order to achieve safe battery charging and extend the battery life and charge and discharge times, constant current and constant voltage charging methods are usually adopted. That is, the whole charging process is divided into two charging stages: constant current and constant voltage. In the initial charging stage, the constant current charging mode is adopted, and the battery voltage will increase. When the battery voltage reaches the set charging voltage, the constant voltage charging mode is adopted, and the charging current will gradually decrease until it reaches the charging cut-off current, and the charging is completed.

[0004] Generally, wireless power transmission systems charge batteries. Since the equivalent impedance of the battery is constantly changing, it is difficult for the system to output the constant current or voltage required by the battery under a certain input voltage. To solve this problem, there are usually two methods:

[0005] 1. Introduce closed-loop negative feedback control into the system, such as using phase shift or frequency conversion control on the inverter, or adding a DC-DC converter at the transmitting or receiving end; the disadvantage is that it increases the control cost and complexity and reduces the system stability.

[0006] 2. In the system, the structure or parameters of the circuit are changed by a bidirectional switch or a relay switch to realize the conversion of two circuits with different characteristics (constant current output characteristics or constant voltage output characteristics);

[0007] At present, there are three main ways to switch the charging mode using a bidirectional switch or a relay switch:

[0008] 1. Use a bidirectional switch tube to switch the charging mode of the circuit, but this method usually requires additional components and cannot ensure that the system input impedance is resistive during the entire charging process, which is not conducive to improving the system efficiency. Since a bidirectional switch tube is generally composed of two power switching devices in anti-series, this method is not conducive to improving the power density of the entire system.

[0009] 2. Use two bidirectional switch tubes to switch the circuit charging mode. This method uses a large number of switching elements.

[0010] 3. Use two relay switches to switch the circuit charging mode. This method uses a large number of switches. At the same time, the switching speed of the relay switch is slower than that of the power switch device, which is not conducive to the smoothness and speed of the system mode switching.

[0011] Since the parameters of the coupling mechanism are difficult to adjust in practice, it is generally difficult to meet the user's parameter design requirements for different output constant current values ​​and constant voltage values, which is not conducive to the expansion of the application scope of the coupling mechanism. In order to make the output constant current value and constant voltage value configurable independently of the coupling mechanism, it is necessary to increase the parameter design freedom of the entire system.

[0012] Therefore, developing a constant current / constant voltage wireless charging system with high freedom in parameter design while taking into account the advantages of no need for additional components, bidirectional switching tubes and relay switches is of great significance to the application of wireless charging systems. Summary of the invention

[0013] The technical problem to be solved by the present invention is to provide a composite half-bridge reconfigurable device and a wireless charging system based on the device, so as to meet the requirements of constant current charging of the load in the initial stage and constant voltage charging in the later stage, and retain the advantages of the prior art (the system input impedance is resistive during the entire charging process, the control is simple, the system works stably and the structure is simple, etc.), without using additional components, bidirectional switching tubes and relay switches, further reducing the amount of switching tubes, enhancing the smoothness and rapidity of system mode switching, and increasing the freedom of system parameter design at the same time, so that it has configurable output constant current value and constant voltage value independent of the coupling mechanism, further expanding the scope of application of the coupling mechanism.

[0014] In order to solve the above technical problems, the technical solution adopted by the present invention is:

[0015] A composite half-bridge reconfigurable device includes a DC power supply E, a first switch S1, a second switch S2, a third switch S3, a fourth switch S4, an a-phase terminal, a b-phase terminal, a c-phase terminal, an A-phase output terminal, a B-phase output terminal, a first compensator P1, a second compensator P2 and a third compensator P3; the specific connection method is:

[0016] One end of the DC power source E is connected to one end of the first switch S1, and the other end of the DC power source E is connected to the c-phase terminal, one end of the third switch S3 and one end of the fourth switch S4; the other end of the first switch S1 is connected to the a-phase terminal, the A-phase output terminal and one end of the second switch S2; the other end of the second switch S2 is connected to the b-phase terminal, one end of the first compensator P1 and the other end of the third switch S3; the other end of the first compensator P1 is connected to one end of the second compensator P2 and one end of the third compensator P3; the other end of the fourth switch S4 is connected to the other end of the second compensator P2; the other end of the third compensator P3 is connected to the B-phase output terminal;

[0017] The first compensator P1 and the second compensator P2 have the following three configurations:

[0018] (1) The first compensator P1 and the second compensator P2 are capacitor and capacitor respectively;

[0019] (2) The first compensator P1 and the second compensator P2 are capacitors and inductors respectively;

[0020] (3) The first compensator P1 and the second compensator P2 are inductors and capacitors respectively;

[0021] The third compensator P3 is configured as a capacitor or an inductor.

[0022] A further improvement of the technical solution of the present invention is that the first switch S1, the second switch S2, the third switch S3, and the fourth switch S4 are all power field effect transistors with body diodes.

[0023] A wireless charging system based on a composite half-bridge reconfigurable device comprises a transmitting part and a receiving part, wherein the transmitting part comprises the composite half-bridge reconfigurable device and a transmitting coil L connected in sequence p1 The receiving part includes a receiving coil L connected in sequence s1 , the first receiving end compensation capacitor C s1 , receiving end compensation inductor L 21 , rectifier filter circuit RF1 and load Ⅰ, and at the first receiving end compensation capacitor C s1 and the receiving end compensation inductor L 21 The connection point and receiving coil L s1 A second receiving end compensation capacitor C is connected between the connection point with the rectifier filter circuit RF1 21 , wherein the second compensator P2 and the second receiving end compensation capacitor C in the composite half-bridge reconfigurable device 21 These are components with adjustable impedance values.

[0024] A further improvement of the technical solution of the present invention is that: the first compensator P1, the second compensator P2, and the third compensator P3 in the composite half-bridge reconfigurable device are respectively the second transmitter compensation capacitor C 11 , transmitter compensation inductor L 11 , the first transmitting end compensation capacitor C p1 ;

[0025] By reconfiguring the composite half-bridge reconfigurable device, two configurations can be generated in combination, as follows:

[0026] set up is the output voltage value of DC power supply E, U ab is the output voltage between the a-phase terminal and the b-phase terminal, U ac is the output voltage between the a-phase terminal and the c-phase terminal;

[0027] Constant current mode configuration 1: the second switch S2 and the fourth switch S4 are normally on, the first switch S1 and the third switch S3 are controlled by complementary PWM signals with dead zones, U ac The amplitude is 0 and The device works in half-bridge mode. The first compensator P1, the second compensator P2 and the third compensator P3 are all in the energy transmission channel. The system works in constant current mode and outputs a constant current to the load I, that is, provides a set constant charging current to the load I, which is suitable for the initial charging stage.

[0028] Constant voltage mode configuration 2: the third switch S3 is normally on, the fourth switch S4 is normally off, the first switch S1 and the second switch S2 are controlled by complementary PWM signals with dead zone, U ab The amplitude is 0 and The device works in half-bridge mode, the first compensator P1 and the third compensator P3 are in the energy transmission channel, and the second compensator P2 is not in the energy transmission channel. The system works in constant voltage mode and outputs a constant voltage to load I, that is, provides a set constant charging voltage to load I, which is suitable for the late charging period when the voltage of load I reaches the charging set voltage;

[0029] The system parameters are determined as follows:

[0030] The second receiving end compensation capacitor C 21 Capacitance value Determined by formula (1):

[0031]

[0032] The transmitter compensation inductor L 11 Inductance value Determined by formula (1) and formula (2):

[0033]

[0034] The second transmitting end compensation capacitor C 11 Capacitance value Determined by formula (2) and formula (3):

[0035]

[0036] The first transmitting end compensation capacitor C p1 Capacitance value Determined by equation (2) and equation (4):

[0037]

[0038] The receiving end compensation inductor L 21 Inductance value Determined by formula (1) and formula (5):

[0039]

[0040] The first receiving end compensation capacitor C s1 Capacitance value Determined by equations (5) and (6):

[0041]

[0042] In formulas (1), (2), (3), (4), (5), and (6), is the output voltage value of the DC power supply E, π is the circumference of the circle, ω1 is the operating angular frequency of the system, I B1 To set the charging current, U B1 To set the charging voltage, M1 is the transmitting coil L p1 With receiving coil L s1 The mutual inductance between The transmitting coil L p1 The inductance value, The receiving coil L s1 The inductance value.

[0043] A wireless charging system based on a composite half-bridge reconfigurable device comprises a transmitting part and a receiving part, wherein the transmitting part comprises the composite half-bridge reconfigurable device, a first transmitting end compensation capacitor C connected in sequence p2 and the transmitting coil L p2 , and in the composite half-bridge reconfigurable device, the A phase output terminal is connected to the transmitting coil L p2 The connection point and the B-phase output terminal and the first transmitting terminal compensation capacitor C of the composite half-bridge reconfigurable device p2A second transmitter compensation capacitor C is connected between the connection points 22 The receiving part includes a receiving coil L connected in sequence s2 , receiving end compensation capacitor C s2 , a rectifier filter circuit RF2 and a load II, wherein the second compensator P2 and the second transmitter compensation capacitor C in the composite half-bridge reconfigurable device 22 All of them are components with adjustable impedance values;

[0044] By reconfiguring the composite half-bridge reconfigurable device, two configurations can be generated in combination, as follows:

[0045] set up is the output voltage value of DC power supply E, U ab is the output voltage between the a-phase terminal and the b-phase terminal, U ac is the output voltage between the a-phase terminal and the c-phase terminal;

[0046] Constant current mode configuration 1: the second switch S2 and the fourth switch S4 are normally on, the first switch S1 and the third switch S3 are controlled by complementary PWM signals with dead zones, U ac The amplitude is 0 and The device works in half-bridge mode. The first compensator P1, the second compensator P2 and the third compensator P3 are all in the energy transmission channel. The system works in constant current mode and outputs a constant current to the load II, that is, provides a set constant charging current to the load II, which is suitable for the initial charging stage.

[0047] Constant voltage mode configuration 2: the third switch S3 is normally on, the fourth switch S4 is normally off, the first switch S1 and the second switch S2 are controlled by complementary PWM signals with dead zone, U ab The amplitude is 0 and The device works in half-bridge mode. The first compensator P1 and the third compensator P3 are in the energy transmission channel, while the second compensator P2 is not in the energy transmission channel. The system works in constant voltage mode and outputs a constant voltage to the load II, that is, provides a set constant charging voltage to the load II. It is suitable for the late charging period when the voltage of the load II reaches the set charging voltage.

[0048] The system parameters are determined as follows:

[0049] The second transmitting end compensation capacitor (C 22 ) capacitance value Determined by formula (16):

[0050]

[0051] The impedance value of the second compensator P2 is Determined by equations (16) and (17):

[0052]

[0053] The impedance value of the first compensator P1 is Determined by equations (17) and (18):

[0054]

[0055] The impedance value of the third compensator P3 is Determined by equations (16), (17) and (19):

[0056]

[0057] The first transmitting end compensation capacitor (C p2 ) capacitance value Determined by equation (16) and equation (20):

[0058]

[0059] The receiving end compensation capacitor (C s2 ) capacitance value Determined by formula (21):

[0060]

[0061] In formulas (16), (17), (18), (19), (20), and (21), is the output voltage value of the DC power supply E, j is the imaginary unit, π is the circumference of a circle, ω2 is the operating angular frequency of the system, I B2 To set the charging current, U B2 To set the charging voltage, M2 is the transmitting coil L p2 With receiving coil L s2 The mutual inductance between The transmitting coil L p2 The inductance value, The receiving coil L s2 The inductance value.

[0062] A further improvement of the technical solution of the present invention is that: when the first compensator P1, the second compensator P2, and the third compensator P3 in the composite half-bridge reconfigurable device are respectively the third transmitter compensation capacitor C 12 , the first transmitting end compensation inductor L 12 , the second transmitter compensation inductor L 22 The specific system parameters are determined as follows:

[0063] Since the second compensator P2 is specifically the first transmitting end compensation inductor L 12 , so the first transmitter compensation inductor L 12 Inductance value Determined by equation (17) and equation (22):

[0064]

[0065] Since the first compensator P1 is specifically a third transmitting end compensation capacitor C 12 , so the third transmitter compensation capacitor C 12 Capacitance value Determined by equation (18) and equation (23):

[0066]

[0067] Since the third compensator P3 is specifically the second transmitting end compensation inductor L 22 , so the second transmitter compensation inductor L 22 Inductance value Determined by equation (19) and equation (24):

[0068]

[0069] A further improvement of the technical solution of the present invention is that: the first compensator P1, the second compensator P2, and the third compensator P3 in the composite half-bridge reconfigurable device are respectively the first transmitter compensation inductor L 13 , the third transmitter compensation capacitor C 13 , the second transmitter compensation inductor L 23 .

[0070] A further improvement of the technical solution of the present invention is that: the first compensator P1, the second compensator P2, and the third compensator P3 in the composite half-bridge reconfigurable device are respectively the transmitter compensation inductor L 14 , the third transmitter compensation capacitor C 14 , the fourth transmitter compensation capacitor C 34 .

[0071] Due to the adoption of the above technical solution, the technical progress achieved by the present invention is:

[0072] 1. The composite half-bridge reconfigurable device proposed in the present invention can help the wireless charging system to output both a constant current independent of load changes and a constant voltage independent of load changes at a constant operating frequency, meeting the requirements of constant current charging in the initial stage of the load and constant voltage charging in the later stage. In addition, the system works at one frequency without frequency bifurcation, ensuring stable operation of the system.

[0073] 2. While meeting the requirements of constant current charging in the initial stage of the load and constant voltage charging in the later stage, the present invention maintains the advantages of the prior art, namely: 1. The equivalent input impedance in both the constant current and constant voltage working modes is resistive, that is, the inverter output voltage and current are in phase, which effectively reduces the reactive power loss in the system and reduces the capacity requirement of the inverter; 2. The structure is simple, there is no complicated control strategy, there is no need to adjust the inverter DC input voltage or add an additional adjustment circuit, and the control is simple, convenient and reliable;

[0074] 3. Compared with the prior art, the present invention does not require additional components, bidirectional switch tubes and relay switches, and the amount of switch tubes used is less, resulting in high power density, low cost, and better smoothness and speed of system mode switching; the parameter design freedom of the wireless charging system is high, and it has configurable output constant current value and constant voltage value independent of the coupling mechanism, which is conducive to the expansion of the application scope of the coupling mechanism.

[0075] 4. The composite half-bridge reconfigurable device proposed in the present invention is not only applicable to electromagnetic induction coupling wireless charging systems, but also to other types of wireless charging systems based on topology reconstruction. BRIEF DESCRIPTION OF THE DRAWINGS

[0076] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings required for use in the embodiments are briefly introduced below. It should be understood that the following drawings are only some embodiments of the present invention and should not be regarded as limiting the scope. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0077] Figure 1 A schematic diagram of a composite half-bridge reconfigurable device provided in an embodiment of the present invention;

[0078] Figure 2 is a schematic diagram of the circuit structure of embodiment 1 of the present invention;

[0079] Figure 3 The composite half-bridge reconfigurable device in Example 1 of the present invention can be combined to produce two configuration diagrams; (a) constant current mode configuration 1; (b) constant voltage mode configuration 2;

[0080] Figure 4 It is a key waveform diagram of the composite half-bridge reconfigurable device in Example 1 of the present invention in constant voltage mode configuration 2 while working under heavy load;

[0081] Figure 5 It is a key waveform diagram of the composite half-bridge reconfigurable device in Example 1 of the present invention in constant voltage mode configuration 2 while working under light load;

[0082] Figure 6is an equivalent circuit diagram of Example 1 of the present invention in a constant current output working mode;

[0083] Figure 7 is an equivalent circuit diagram of Example 1 of the present invention in a constant voltage output working mode;

[0084] Figure 8 is a schematic diagram of a first circuit structure of Embodiment 2 of the present invention;

[0085] Fig. 9 is an equivalent circuit diagram of embodiment 2 of the present invention in a constant current output working mode;

[0086] Fig.10 is an equivalent circuit diagram of Example 2 of the present invention in a constant voltage output working mode;

[0087] Fig.11 is a schematic diagram of a second circuit structure of Embodiment 2 of the present invention;

[0088] Fig.12 This is a third circuit structure schematic diagram of Example 2 of the present invention. DETAILED DESCRIPTION

[0089] The embodiment of the present invention solves the problems existing in the prior art in that a small number of switch tubes are used, no additional components and bidirectional switch tubes and relay switches are required, the input impedance of the system is resistive during the entire charging process, and a configurable output constant current value and constant voltage value independent of the coupling mechanism are difficult to be compatible at the same time by providing a composite half-bridge reconfigurable device and a wireless charging system based on the device. By reconstructing the composite half-bridge reconfigurable device, the wireless charging system can meet the requirements of initial constant current charging and later constant voltage charging of the load, while ensuring that its equivalent input impedance in both constant current and constant voltage working modes is resistive; and the number of switches used is small, no additional components, bidirectional switch tubes and relay switches are required, the structure is simple, the power density is high, and the cost is low.

[0090] In order to make the purpose, technical solutions and advantages of the present invention clearer, the present invention will be further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described are only used to explain the present invention and are not used to limit the present invention. That is, the embodiments described 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 those skilled in the art without making creative work are within the scope of protection of the present invention.

[0091] It should be noted that relational terms such as "first", "second" and "configuration 1" are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any actual relationship or order between these entities or operations; and, the term "comprise" or any other variation thereof is intended to cover non-exclusive inclusion, so that a process, method, article or apparatus that includes a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or apparatus.

[0092] like Figure 1 As shown, a composite half-bridge reconfigurable device includes a DC power supply E, a first switch S1, a second switch S2, a third switch S3, a fourth switch S4, an a-phase terminal, a b-phase terminal, a c-phase terminal, an A-phase output terminal, a B-phase output terminal, a first compensator P1, a second compensator P2 and a third compensator P3; the specific connection method is:

[0093] One end of the DC power source E is connected to one end of the first switch S1, and the other end of the DC power source E is connected to the c-phase terminal, one end of the third switch S3 and one end of the fourth switch S4; the other end of the first switch S1 is connected to the a-phase terminal, the A-phase output terminal and one end of the second switch S2; the other end of the second switch S2 is connected to the b-phase terminal, one end of the first compensator P1 and the other end of the third switch S3; the other end of the first compensator P1 is connected to one end of the second compensator P2 and one end of the third compensator P3; the other end of the fourth switch S4 is connected to the other end of the second compensator P2; the other end of the third compensator P3 is connected to the B-phase output terminal;

[0094] The first compensator P1 and the second compensator P2 may be a capacitor and a capacitor respectively; the first compensator P1 and the second compensator P2 may be a capacitor and an inductor respectively; the first compensator P1 and the second compensator P2 may be an inductor and a capacitor respectively; the third compensator P3 may be a capacitor; the third compensator P3 may also be an inductor.

[0095] The following embodiments are described by taking an electromagnetic induction coupling type wireless charging system as an example.

[0096] Example 1

[0097] like Figure 2 As shown, the first specific embodiment of the present invention is a wireless charging system based on a composite half-bridge reconfigurable device, the wireless charging system is a constant current / constant voltage electromagnetic induction coupling type, and is composed of a transmitting part and a receiving part, the transmitting part includes a composite half-bridge reconfigurable device and a transmitting coil L connected in sequence p1 The receiving part includes a receiving coil L connected in sequence s1 , the first receiving end compensation capacitor C s1, receiving end compensation inductor L 21 , rectifier filter circuit RF1 and load Ⅰ, and at the first receiving end compensation capacitor C s1 and the receiving end compensation inductor L 21 The connection point and receiving coil L s1 A second receiving end compensation capacitor C is connected between the connection point with the rectifier filter circuit RF1 21 .

[0098] The first compensator P1, the second compensator P2, and the third compensator P3 in the composite half-bridge reconfigurable device are respectively the first transmitter compensation capacitor C 11 , transmitter compensation inductor L 11 , the second transmitter compensation capacitor C p1 The first switch S1, the second switch S2, the third switch S3, and the fourth switch S4 are all MOSFETs with body diodes. MOSFET refers to a power field effect transistor, or power MOSFET for short. Among them, the transmitter compensation inductor L 11 and the second receiving end compensation capacitor C 21 These are components with adjustable impedance values.

[0099] By reconfiguring the composite half-bridge reconfigurable device, two configurations can be combined and generated, such as Figure 3 As shown, is the output voltage value of DC power supply E, U ab is the output voltage between the a-phase terminal and the b-phase terminal, U ac is the output voltage between the a-phase terminal and the c-phase terminal;

[0100] like Figure 3 (a) shows the switching mode of constant current mode configuration 1: the second switch S2 and the fourth switch S4 are normally on, the first switch S1 and the third switch S3 are controlled by complementary PWM signals with dead zone, U ac The amplitude is 0 and The device operates in half-bridge mode, and the first transmitter compensation capacitor C 11 , transmitter compensation inductor L 11 , the second transmitter compensation capacitor C p1 All are in the energy transmission channel, the system works in constant current mode, and outputs constant current to load I;

[0101] like Figure 3 (b) shows the switching mode of constant voltage mode configuration 2: the third switch S3 is normally on, the fourth switch S4 is normally off, the first switch S1 and the second switch S2 are controlled by complementary PWM signals with dead zone, U ab The amplitude is 0 and The device operates in half-bridge mode, and the first transmitter compensation capacitor C 11 , the second transmitter compensation capacitor C p1 In the energy transmission channel, the transmitter compensation inductor L 11 When not in the energy transmission channel, the system works in constant voltage mode and outputs a constant voltage to load I;

[0102] like Figure 4 As shown, it is a key waveform diagram of Example 1 when working under heavy load in constant voltage mode;

[0103] like Figure 5 As shown, it is a key waveform diagram of Example 1 when working under light load in constant voltage mode;

[0104] Among them U ac is the output voltage between the a-phase terminal and the c-phase terminal, U S4 is the voltage across the fourth switch S4, U C11 The first transmitter compensation capacitor C 11 The voltage across the terminals, I L11 The current flowing through the transmitter compensation inductor L 11 current; see Figure 4 and Figure 5 It can be found that the first transmitting end compensation capacitor C connected in parallel with the fourth switch S4 11 The voltage on the MOSFET is charged and kept above zero voltage, causing the body diode in the fourth switch S4 to be cut off due to reverse voltage. However, due to the parasitic capacitance in the actual MOSFET, the transmitter compensation inductor L 11 The branch where the current flows is less than 5mA, which is equivalent to realizing the transmitter compensation inductance L 11 Not in the energy transfer channel.

[0105] The system parameters in this embodiment 1 are determined in the following manner:

[0106] The second receiving end compensation capacitor C 21 Capacitance value Determined by formula (1):

[0107]

[0108] The transmitter compensation inductor L 11 Inductance value Determined by formula (1) and formula (2):

[0109]

[0110] The first transmitting end compensation capacitor C 11 Capacitance value Determined by formula (2) and formula (3):

[0111]

[0112] The second transmitting end compensation capacitor (C p1 ) capacitance value Determined by formula (2) and formula (4):

[0113]

[0114] The receiving end compensation inductor L 21 Inductance value Determined by equation (1) and equation (5):

[0115]

[0116] The first receiving end compensation capacitor C s1 Capacitance value Determined by equations (5) and (6):

[0117]

[0118] In formulas (1), (2), (3), (4), (5), and (6), is the output voltage value of the DC power supply E, π is the circumference of the circle, ω1 is the operating angular frequency of the system, I B1 To set the charging current, U B1 To set the charging voltage, M1 is the transmitting coil L p1 With receiving coil L s1 The mutual inductance between The transmitting coil L p1 The inductance value, The receiving coil L s1 The inductance value.

[0119] Theoretical analysis is performed using fundamental wave analysis method for Example 1 of the present invention:

[0120] like Figure 6 As shown, this is the equivalent circuit of the system when it outputs constant current, where For U ac The AC fundamental content, Z in1 is the input impedance of the system, is the AC input current of the system, R o1 is the input equivalent AC resistance of the rectifier filter circuit (RF1), They are the input voltage and input current of the rectifier and filter circuit (RF1) respectively.

[0121] When the first transmitter compensation capacitor C 11 Capacitance value Transmitter compensation inductor L11 Inductance value The second transmitter compensation capacitor C p1 Capacitance value Transmitter coil L p1 Inductance value Receiving coil L s1 Inductance value The first receiving end compensation capacitor C s1 Capacitance value The second receiving end compensation capacitor C 21 Capacitance value and the receiving end compensation inductor L 21 Inductance value Satisfies the relationship (7):

[0122]

[0123] When the input impedance of the system is constant, the equivalent impedance of the input end of the system is derived by the principle of series and parallel connection of component impedances, and the input impedance Z of the system when the constant current output is obtained by simplifying equation (8) in combination with equation (7): in1 for:

[0124]

[0125] Formula (8) shows that in the constant current working mode, the input impedance of the system is purely resistive, which effectively reduces the reactive power loss in the system.

[0126] According to the principle of impedance parallel shunt, the input current of the rectifier filter circuit RF1 is derived The effective value of for:

[0127]

[0128] In formula (9), is the output voltage U ac AC fundamental content Valid values.

[0129] Furthermore, combined with the half-bridge inverter output voltage U ac AC fundamental content The effective value of The output voltage value of the DC power supply E The relationship between the input current of the full-bridge rectifier Effective value With the system output current I B1 Relationship between:

[0130]

[0131] Calculate the system output current IB1 for:

[0132]

[0133] Formula (11) shows that the system output current I B1 Regardless of load I, when the transmitting coil L p1 With receiving coil L s1 The mutual inductance value M1 and the output voltage value of the DC power supply E When the system operating angular frequency ω1 is fixed, the system output current I in constant current mode is B1 The value of the transmitter compensation inductor L can be adjusted 11 Inductance value and the second receiving end compensation capacitor C 21 Capacitance value To configure, the system has a configurable output constant current value independent of the coupling mechanism.

[0134] like Figure 7 As shown, this is the equivalent circuit of the system when it outputs constant voltage, where For U ab The AC fundamental content, is the AC input current of the system.

[0135] The equivalent impedance of the system input end is derived by the principle of series and parallel connection of component impedances, and the formula (12) is simplified by combining the formula (7) to obtain the input impedance Z of the system at constant voltage output. in1 for:

[0136]

[0137] Formula (12) shows that in the constant voltage working mode, the input impedance of the system is purely resistive, which effectively reduces the reactive power loss in the system.

[0138] According to the principle of impedance parallel shunt, the input voltage of the rectifier filter circuit (RF1) is derived The effective value of for:

[0139]

[0140] In formula (13), is the output voltage U ab AC fundamental content Valid values.

[0141] Furthermore, combined with the half-bridge inverter output voltage U ab AC fundamental content The effective value of The output voltage value of the DC power supply E The relationship between the input voltage of the full-bridge rectifier Effective value With the system output voltage U B1 Relationship between:

[0142]

[0143] Calculate the system output voltage U B1 for:

[0144]

[0145] Formula (15) shows that the system output voltage U B1 Regardless of load I, when the transmitting coil L p1 With receiving coil L s1 The mutual inductance value M1 and the output voltage value of the DC power supply E When the system operating angular frequency ω1 is fixed, the system output voltage U in constant voltage mode is B1 The value of the second receiving end compensation capacitor C can be adjusted 21 Capacitance value To configure, the system has a configurable output constant voltage value independent of the coupling mechanism.

[0146] Example 2

[0147] like Figure 8 As shown, the second specific embodiment of the present invention is a wireless charging system based on a composite half-bridge reconfigurable device, the wireless charging system is a constant current / constant voltage electromagnetic induction coupling type, and is composed of a transmitting part and a receiving part, the transmitting part includes a composite half-bridge reconfigurable device, a first transmitting end compensation capacitor C connected in sequence p2 and the transmitting coil L p2 , and in the composite half-bridge reconfigurable device, the A phase output terminal is connected to the transmitting coil L p2 The connection point and the B-phase output terminal and the first transmitting terminal compensation capacitor C of the composite half-bridge reconfigurable device p2 A second transmitter compensation capacitor C is connected between the connection points 22 The receiving part includes a receiving coil L connected in sequence s2 , receiving end compensation capacitor C s2 , rectifier and filter circuit RF2 and load II.

[0148] The first compensator P1, the second compensator P2, and the third compensator P3 in the composite half-bridge reconfigurable device are respectively the third transmitter compensation capacitor C 12 , the first transmitting end compensation inductor L 12 , the second transmitter compensation inductor L 22The first switch S1, the second switch S2, the third switch S3, and the fourth switch S4 are all MOSFETs with body diodes. MOSFET refers to a power field effect transistor, or power MOSFET for short. Among them, the first transmitter compensation inductor L 12 and the second transmitter compensation capacitor C 22 These are components with adjustable impedance values.

[0149] By reconfiguring the composite half-bridge reconfigurable device, two configurations can be combined and generated. is the output voltage value of DC power supply E, U ab is the output voltage between the a-phase terminal and the b-phase terminal, U ac is the output voltage between the a-phase terminal and the c-phase terminal;

[0150] Constant current mode configuration 1: the second switch S2 and the fourth switch S4 are normally on, the first switch S1 and the third switch S3 are controlled by complementary PWM signals with dead zones, U ac The amplitude is 0 and The device operates in half-bridge mode, and the third transmitter compensation capacitor C 12 , the first transmitting end compensation inductor L 12 , the second transmitter compensation inductor L 22 All are in the energy transmission channel, the system works in constant current mode, and outputs constant current to load II;

[0151] Constant voltage mode configuration 2: the third switch S3 is normally on, the fourth switch S4 is normally off, the first switch S1 and the second switch S2 are controlled by complementary PWM signals with dead zone, U ab The amplitude is 0 and The device operates in half-bridge mode, and the third transmitter compensation capacitor C 12 , the second transmitter compensation inductor L 22 In the energy transmission channel, the first transmitting end compensation inductor L 12 When not in the energy transmission channel, the system works in constant voltage mode and outputs a constant voltage to load II.

[0152] The system parameters in this embodiment 2 are determined in the following manner:

[0153] The second transmitting end compensation capacitor (C 22 ) capacitance value Determined by formula (16):

[0154]

[0155] The impedance value of the second compensator P2 is Determined by equations (16) and (17):

[0156]

[0157] The impedance value of the first compensator P1 is Determined by equations (17) and (18):

[0158]

[0159] The impedance value of the third compensator P3 is Determined by equations (16), (17) and (19):

[0160]

[0161] The first transmitting end compensation capacitor (C p2 ) capacitance value Determined by equation (16) and equation (20):

[0162]

[0163] The receiving end compensation capacitor (C s2 ) capacitance value Determined by formula (21):

[0164]

[0165] Since the second compensator P2 is specifically the first transmitting end compensation inductor L 12 , so the first transmitter compensation inductor L 12 Inductance value Determined by equation (17) and equation (22):

[0166]

[0167] Since the first compensator P1 is specifically a third transmitting end compensation capacitor C 12 , so the third transmitter compensation capacitor C 12 Capacitance value Determined by equation (18) and equation (23):

[0168]

[0169] Since the third compensator P3 is specifically the second transmitting end compensation inductor L 22 , so the second transmitter compensation inductor L 22 Inductance value Determined by equation (19) and equation (24):

[0170]

[0171] In formulas (16), (17), (18), (19), (20), (21), (22), (23), and (24), is the output voltage value of the DC power supply (E), j is the imaginary unit, π is the circumference of a circle, ω2 is the system operating angular frequency, I B2 To set the charging current, U B2 To set the charging voltage, M2 is the transmitting coil (L p2 ) and the receiving coil (L s2 ), For the transmitting coil (L p2 ) inductance value, For the receiving coil (L s2 ) inductance value.

[0172] Theoretical analysis is performed using fundamental wave analysis method for Example 2 of the present invention:

[0173] Fig. 9 is the equivalent circuit of the system when it outputs constant current, where For U ac The AC fundamental content, Z in2 is the input impedance of the system, is the AC input current of the system, R o2 is the input equivalent AC resistance of the rectifier filter circuit RF2, They are the input voltage and input current of the rectifier and filter circuit RF2 respectively.

[0174] When the first transmitter compensation capacitor C p2 Capacitance value The second transmitter compensation capacitor C 22 Capacitance value The third transmitter compensation capacitor C 12 Capacitance value The first transmitter compensation inductor L 12 Inductance value The second transmitter compensation inductor L 22 Inductance value Transmitter coil L p2 Inductance value Receiving coil L s2 Inductance value Receiving end compensation capacitor C s2 Capacitance value Satisfies the relationship (25):

[0175]

[0176] When the input impedance of the system is 1, the equivalent impedance of the input end of the system is derived by the principle of series and parallel connection of component impedances, and the input impedance Z of the system when the constant current output is obtained by simplifying equation (26) in combination with equation (25): in2 for:

[0177]

[0178] Equation (26) shows that in the constant current working mode, the input impedance of the system is purely resistive, which effectively reduces the reactive power loss in the system.

[0179] According to the principle of impedance parallel shunt, the input current of the rectifier filter circuit RF2 is derived The effective value of for:

[0180]

[0181] In formula (27), is the output voltage U ac AC fundamental content Valid values.

[0182] Furthermore, combined with the half-bridge inverter output voltage U ac AC fundamental content The effective value of The output voltage value of the DC power supply E The relationship between the input current of the full-bridge rectifier Effective value With the system output current I B2 Relationship between:

[0183]

[0184] Calculate the system output current I B2 for:

[0185]

[0186] Formula (29) shows that the system output current I B2 Regardless of load II, when the transmitting coil L p2 With receiving coil L s2 The mutual inductance value M2 and the output voltage value of the DC power supply E When the system operating angular frequency ω2 is fixed, the system output current I in constant current mode is B2 The value of the first transmitter compensation inductor L can be adjusted 12 Inductance value and the second transmitter compensation capacitor C 22 Capacitance value To configure, the system has a configurable output constant current value independent of the coupling mechanism.

[0187] like Fig.10 As shown, this is the equivalent circuit of the system when it outputs constant voltage, where For U ab The AC fundamental content, is the AC input current of the system.

[0188] The equivalent impedance of the system input end is derived by the principle of series and parallel connection of component impedances, and the formula (30) is simplified by combining formula (25) to obtain the input impedance Z of the system at constant voltage output. in2 for:

[0189]

[0190] Equation (30) shows that in the constant voltage working mode, the input impedance of the system is purely resistive, which effectively reduces the reactive power loss in the system.

[0191] According to the principle of impedance parallel shunt, the input voltage of the rectifier filter circuit RF2 is derived The effective value of for:

[0192]

[0193] In formula (31), is the output voltage U ab AC fundamental content Valid values.

[0194] Furthermore, combined with the half-bridge inverter output voltage U ab AC fundamental content The effective value of The output voltage value of the DC power supply E The relationship between the input voltage of the full-bridge rectifier Effective value With the system output voltage U B2 Relationship between:

[0195]

[0196] Calculate the system output voltage U B2 for:

[0197]

[0198] Formula (33) shows that the system output voltage U B2 Regardless of load II, when the transmitting coil L p2 With receiving coil L s2The mutual inductance value M2 and the output voltage value of the DC power supply E When the system operating angular frequency ω2 is fixed, the system output voltage U in constant voltage mode is B2 The value of the second transmitter compensation capacitor C can be adjusted 22 Capacitance value To configure, the system has a configurable output constant voltage value independent of the coupling mechanism.

[0199] like Fig.11 As shown, when the first compensator P1, the second compensator P2, and the third compensator P3 in the composite half-bridge reconfigurable device are respectively the first transmitter compensation inductor L 13 , the third transmitter compensation capacitor C 13 , the second transmitter compensation inductor L 23 When , the corresponding functions in Example 2 can also be realized. The system parameter determination method corresponds to the configured parameters. The principle is the same as formulas (16)-(21) and will not be described in detail in the present invention.

[0200] like Fig.12 As shown, when the first compensator P1, the second compensator P2, and the third compensator P3 in the composite half-bridge reconfigurable device are respectively the transmitter compensation inductor L 14 , the third transmitter compensation capacitor C 14 , the fourth transmitter compensation capacitor C 34 When , the corresponding functions in Example 2 can also be realized. The system parameter determination method corresponds to the configured parameters. The principle is the same as formulas (16)-(21) and will not be described in detail in the present invention.

[0201] The various embodiments in this specification are described in a progressive manner, and each embodiment focuses on the differences from other embodiments. Similar parts between the various embodiments can be referenced to each other.

[0202] The above description is only a preferred embodiment of the present invention and is not intended to be any formal or substantial limitation of the present invention. Any equivalent changes, modifications and evolutions made by technicians familiar with the profession without departing from the spirit and scope of the present invention by using the technical contents described above are all equivalent embodiments of the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A composite half-bridge reconfigurable device, characterized in that: It includes a DC power supply E, a first switch S1, a second switch S2, a third switch S3, a fourth switch S4, a phase terminal, a phase terminal, a phase terminal, a phase output terminal, a phase output terminal, a first compensator P1, a second compensator P2 and a third compensator P3; the specific connection method is: One end of the DC power source E is connected to one end of the first switch S1, and the other end of the DC power source E is connected to the c-phase terminal, one end of the third switch S3 and one end of the fourth switch S4; the other end of the first switch S1 is connected to the a-phase terminal, the A-phase output terminal and one end of the second switch S2; the other end of the second switch S2 is connected to the b-phase terminal, one end of the first compensator P1 and the other end of the third switch S3; the other end of the first compensator P1 is connected to one end of the second compensator P2 and one end of the third compensator P3; the other end of the fourth switch S4 is connected to the other end of the second compensator P2; the other end of the third compensator P3 is connected to the B-phase output terminal; The first compensator P1 and the second compensator P2 have the following three configurations: (1) The first compensator P1 and the second compensator P2 are capacitor and capacitor respectively; (2) The first compensator P1 and the second compensator P2 are capacitors and inductors respectively; (3) The first compensator P1 and the second compensator P2 are inductors and capacitors respectively; The third compensator P3 is configured as a capacitor or an inductor.

2. A composite half-bridge reconfigurable device according to claim 1, characterized in that: The first switch S1 , the second switch S2 , the third switch S3 , and the fourth switch S4 are all power field effect transistors with body diodes.

3. A wireless charging system based on the composite half-bridge reconfigurable device according to any one of claims 1 to 2, characterized in that: It includes a transmitting part and a receiving part, wherein the transmitting part includes the composite half-bridge reconfigurable device and the transmitting coil L connected in sequence p1 The receiving part includes a receiving coil L connected in sequence s1 , the first receiving end compensation capacitor C s1 , receiving end compensation inductor L 21 , rectifier filter circuit RF1 and load Ⅰ, and at the first receiving end compensation capacitor C s1 and the receiving end compensation inductor L 21 The connection point and receiving coil L s1 A second receiving end compensation capacitor C is connected between the connection point with the rectifier filter circuit RF1 21 , wherein the second compensator P2 and the second receiving end compensation capacitor C in the composite half-bridge reconfigurable device 21 These are components with adjustable impedance values.

4. The wireless charging system based on the composite half-bridge reconfigurable device according to claim 3 is characterized in that: The first compensator P1, the second compensator P2, and the third compensator P3 in the composite half-bridge reconfigurable device are respectively the second transmitter compensation capacitor C 11 , transmitter compensation inductor L 11 , the first transmitting end compensation capacitor C p1 ; By reconfiguring the composite half-bridge reconfigurable device, two configurations can be generated in combination, as follows: set up is the output voltage value of DC power supply E, U ab is the output voltage between the a-phase terminal and the b-phase terminal, U ac is the output voltage between the a-phase terminal and the c-phase terminal; Constant current mode configuration 1: the second switch S2 and the fourth switch S4 are normally on, the first switch S1 and the third switch S3 are controlled by complementary PWM signals with dead zones, U ac The amplitude is 0 and The device works in half-bridge mode. The first compensator P1, the second compensator P2 and the third compensator P3 are all in the energy transmission channel. The system works in constant current mode and outputs a constant current to the load I, that is, provides a set constant charging current to the load I, which is suitable for the initial charging stage. Constant voltage mode configuration 2: the third switch S3 is normally on, the fourth switch S4 is normally off, the first switch S1 and the second switch S2 are controlled by complementary PWM signals with dead zone, U ab The amplitude is 0 and The device works in half-bridge mode, the first compensator P1 and the third compensator P3 are in the energy transmission channel, and the second compensator P2 is not in the energy transmission channel. The system works in constant voltage mode and outputs a constant voltage to load I, that is, provides a set constant charging voltage to load I, which is suitable for the late charging period when the voltage of load I reaches the charging set voltage; The system parameters are determined as follows: The second receiving end compensation capacitor C 21 Capacitance value Determined by formula (1): The transmitter compensation inductor L 11 Inductance value Determined by formula (1) and formula (2): The second transmitting end compensation capacitor C 11 Capacitance value Determined by formula (2) and formula (3): The first transmitting end compensation capacitor C p1 Capacitance value Determined by equation (2) and equation (4): The receiving end compensation inductor L 21 Inductance value Determined by equation (1) and equation (5): The first receiving end compensation capacitor C s1 Capacitance value Determined by equations (5) and (6): In formulas (1), (2), (3), (4), (5), and (6), is the output voltage value of the DC power supply E, π is the circumference of the circle, ω1 is the operating angular frequency of the system, I B1 To set the charging current, U B1 To set the charging voltage, M1 is the transmitting coil L p1 With receiving coil L s1 The mutual inductance between The transmitting coil L p1 The inductance value, The receiving coil L s1 The inductance value.

5. A wireless charging system based on the composite half-bridge reconfigurable device according to any one of claims 1 to 2, characterized in that: It includes a transmitting part and a receiving part, wherein the transmitting part includes the composite half-bridge reconfigurable device, the first transmitting end compensation capacitor C connected in sequence p2 and the transmitting coil L p2 , and in the composite half-bridge reconfigurable device, the A phase output terminal is connected to the transmitting coil L p2 The connection point and the B-phase output terminal and the first transmitting terminal compensation capacitor C of the composite half-bridge reconfigurable device p2 A second transmitter compensation capacitor C is connected between the connection points 22 The receiving part includes a receiving coil L connected in sequence s2 , receiving end compensation capacitor C s2 , a rectifier filter circuit RF2 and a load II, wherein the second compensator P2 and the second transmitter compensation capacitor C in the composite half-bridge reconfigurable device 22 All of them are components with adjustable impedance values; By reconfiguring the composite half-bridge reconfigurable device, two configurations can be generated in combination, as follows: set up is the output voltage value of DC power supply E, U ab is the output voltage between the a-phase terminal and the b-phase terminal, U ac is the output voltage between the a-phase terminal and the c-phase terminal; Constant current mode configuration 1: the second switch S2 and the fourth switch S4 are normally on, the first switch S1 and the third switch S3 are controlled by complementary PWM signals with dead zones, U ac The amplitude is 0 and The device works in half-bridge mode. The first compensator P1, the second compensator P2 and the third compensator P3 are all in the energy transmission channel. The system works in constant current mode and outputs a constant current to the load II, that is, provides a set constant charging current to the load II, which is suitable for the initial charging stage. Constant voltage mode configuration 2: the third switch S3 is normally on, the fourth switch S4 is normally off, the first switch S1 and the second switch S2 are controlled by complementary PWM signals with dead zone, U ab The amplitude is 0 and The device works in half-bridge mode. The first compensator P1 and the third compensator P3 are in the energy transmission channel, while the second compensator P2 is not in the energy transmission channel. The system works in constant voltage mode and outputs a constant voltage to the load II, that is, provides a set constant charging voltage to the load II. It is suitable for the late charging period when the voltage of the load II reaches the set charging voltage. The system parameters are determined as follows: The second transmitting end compensation capacitor (C 22 ) capacitance value Determined by formula (16): The impedance value of the second compensator P2 is Determined by equations (16) and (17): The impedance value of the first compensator P1 is Determined by equations (17) and (18): The impedance value of the third compensator P3 is Determined by equations (16), (17) and (19): The first transmitting end compensation capacitor (C p2 ) capacitance value Determined by equation (16) and equation (20): The receiving end compensation capacitor (C s2 ) capacitance value Determined by formula (21): In formulas (16), (17), (18), (19), (20), and (21), is the output voltage value of the DC power supply E, j is the imaginary unit, π is the circumference of a circle, ω2 is the operating angular frequency of the system, I B2 To set the charging current, U B2 To set the charging voltage, M2 is the transmitting coil L p2 With receiving coil L s2 The mutual inductance between The transmitting coil L p2 The inductance value, The receiving coil L s2 The inductance value.

6. The wireless charging system based on the composite half-bridge reconfigurable device according to claim 5, characterized in that: When the first compensator P1, the second compensator P2, and the third compensator P3 in the composite half-bridge reconfigurable device are respectively the third transmitter compensation capacitor C 12 , the first transmitting end compensation inductor L 12 , the second transmitter compensation inductor L 22 The specific system parameters are determined as follows: Since the second compensator P2 is specifically the first transmitting end compensation inductor L 12 , so the first transmitter compensation inductor L 12 Inductance value Determined by equation (17) and equation (22): Since the first compensator P1 is specifically a third transmitting end compensation capacitor C 12 , so the third transmitter compensation capacitor C 12 Capacitance value Determined by equation (18) and equation (23): Since the third compensator P3 is specifically the second transmitting end compensation inductor L 22 , so the second transmitter compensation inductor L 22 Inductance value Determined by equation (19) and equation (24):

7. The wireless charging system based on the composite half-bridge reconfigurable device according to claim 5, characterized in that: The first compensator P1, the second compensator P2, and the third compensator P3 in the composite half-bridge reconfigurable device are respectively the first transmitting end compensation inductor L 13 , the third transmitter compensation capacitor C 13 , the second transmitter compensation inductor L 23 .

8. The wireless charging system based on the composite half-bridge reconfigurable device according to claim 5, characterized in that: The first compensator P1, the second compensator P2, and the third compensator P3 in the composite half-bridge reconfigurable device are respectively the transmitter compensation inductor L 14 , the third transmitter compensation capacitor C 14 , the fourth transmitter compensation capacitor C 34 .

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