A Design Method, Device and Equipment for Parameters of a Hybrid Compensation Network of Detuned Wireless Power Transfer with Anti-Offset

Abstract

The present application discloses a method, device and equipment for designing the parameters of a hybrid compensation network for anti-offset detuned wireless power transmission. The method is implemented based on a hybrid compensation circuit. The hybrid compensation equivalent circuit is analyzed from the hybrid compensation circuit; a detuning coefficient is introduced to perform a detuned simplification analysis on the LCC-S equivalent loop, and an expression formula for the tuning parameters of the LCC-S is constructed; by adjusting the detuning coefficient, the target detuning coefficient corresponding to the mutual inductance value of the LCC-S when the derivative of the output power of the LCC-S is 0 is selected based on the output power and the extreme mutual inductance value expression; according to the detuning parameter and the coupling coefficient, a mathematical analysis of the detuning conditions of the two equivalent loops is carried out to obtain a power fluctuation expression; with the minimum power fluctuation as the target, optimization calculation is carried out according to the power fluctuation expression to obtain the target detuning parameter. The present application can solve the technical problem that the existing hybrid topology parameter design depends on the resonance state of the system, and it is impossible to control the output fluctuation in the detuned situation, resulting in a weak anti-offset ability of the system.

Description

Technical Field

[0001] The present application relates to the technical field of circuit topology analysis, and particularly to a method, device and equipment for designing parameters of a hybrid compensation network for anti-offset detuned wireless power transmission. Background Art

[0002] As a new type of intelligent power transmission technology, wireless power transmission technology can get rid of the bondage of cables and has advantages such as high efficiency, safety and strong environmental adaptability. In particular, in the application of electric vehicle charging, the use of wireless power transmission technology can not only solve the problems of long charging time and short cruising range of electric vehicles, but also does not require precise alignment and plugging and unplugging, greatly improving the convenience of charging and using electricity, which has attracted wide attention from countries around the world. However, due to a certain transmission distance between the transmitting side and the receiving side of the magnetic coupling mechanism and no physical connection, it is one of the characteristics of the wireless power transmission system that the coils on both sides are prone to shift.

[0003] Existing wireless power transmission technologies mostly adopt a hybrid topology structure to achieve the purpose of good anti-misalignment tolerance. However, the current design of hybrid topology parameters mostly depends on the resonant state of the system. Once detuned, the output voltage and regulated current fluctuations will be very serious, resulting in a large offset of the system and weak anti-offset ability, which cannot meet the actual needs of the system. Summary of the Invention

[0004] The present application provides a method, device and equipment for designing parameters of a hybrid compensation network for anti-offset detuned wireless power transmission, which is used to solve the technical problem that the existing hybrid topology parameter design depends on the resonant state of the system and cannot control the output fluctuation under the detuned condition, resulting in weak anti-offset ability of the system.

[0005] In view of this, in the first aspect of the present application, a method for designing parameters of a hybrid compensation network for anti-offset detuned wireless power transmission is provided. The method is implemented based on a hybrid compensation circuit, and the hybrid compensation circuit includes: an inverter circuit, a hybrid compensation network and a rectifier circuit;

[0006] The inverter circuit includes two arms composed of 4 MOSFET switches;

[0007] The hybrid compensation network includes a primary compensation network and a secondary compensation network, and is divided into an LCC-S topology network and an S-LCC topology network according to the topology structure;

[0008] The rectifier circuit includes two arms composed of 4 symmetric diodes;

[0009] The hybrid compensation network is connected in parallel with the transmitting end of the inverter circuit and in series with the receiving end of the rectifier circuit;

[0010] The method includes:

[0011] The fundamental wave approximation method is adopted to analyze the hybrid compensation circuit, and a hybrid compensation equivalent circuit is obtained. The hybrid compensation equivalent circuit includes an LCC-S equivalent loop and an S-LCC equivalent loop;

[0012] A detuning coefficient is introduced to perform detuning simplification analysis on the LCC-S equivalent loop, and an LCC-S tuning parameter expression formula is constructed. The LCC-S tuning parameter expression formula includes an LCC-S output power expression and an LCC-S extreme mutual inductance value expression;

[0013] By adjusting the detuning coefficient, based on the LCC-S output power expression and the LCC-S extreme mutual inductance value expression, the detuning coefficient corresponding to the LCC-S mutual inductance value obtained when the derivative value of the LCC-S output power is 0 is selected as the target detuning coefficient;

[0014] According to the detuning parameter and the coupling coefficient, mathematical analysis of the detuning conditions for the LCC-S equivalent loop and the S-LCC equivalent loop is performed to generate a total circuit output power expression and a power fluctuation expression;

[0015] With the goal of minimizing power fluctuation, optimization calculation is performed according to the total circuit output power expression and the power fluctuation expression to obtain the target detuning parameter.

[0016] Preferably, the first MOSFET switch tube and the second MOSFET switch tube in the inverter circuit form the first bridge arm;

[0017] The third MOSFET switch tube and the fourth MOSFET switch tube form the second bridge arm.

[0018] Preferably, the primary compensation network and the secondary compensation network in the hybrid compensation network are connected in a cascaded manner of double compensation topologies, and an LCC-S topology network and an S-LCC topology network are generated in the topological structure form of primary compensation in parallel and secondary compensation in series;

[0019] The LCC-S topology network includes a first compensation inductor and three first compensation capacitors, and the output voltage of the LCC-S topology network is inversely proportional to the offset;

[0020] The S-LCC topology network includes a second compensation inductor and three second compensation capacitors, and the output voltage of the S-LCC topology network is directly proportional to the offset.

[0021] Preferably, the introduction of the detuning coefficient, the detuning simplification analysis of the LCC-S equivalent loop, and the construction of the LCC-S tuning parameter expression formula include:

[0022] Introduce the detuning coefficient, conduct detuning simplification analysis on the LCC-S equivalent circuit, and obtain the expression of the LCC-S equivalent input impedance;

[0023] Analyze the first compensation inductor when the LCC-S equivalent input impedance presents a pure resistive moment according to the LCC-S equivalent input impedance expression;

[0024] Calculate the LCC-S output power expression based on the first compensation inductor and the first mutual inductance value;

[0025] Conduct mutual inductance derivative analysis according to the LCC-S output power expression to obtain the LCC-S extreme mutual inductance value expression.

[0026] Preferably, the mathematical analysis of the detuning conditions for the LCC-S equivalent circuit and the S-LCC equivalent circuit according to the detuning parameters and the coupling coefficient generates the total circuit output power expression and the power fluctuation expression, including:

[0027] Calculate the S-LCC equivalent input impedance when the LCC-S equivalent circuit and the S-LCC equivalent circuit meet the preset resonance conditions according to the detuning parameters;

[0028] Analyze the second compensation inductor when the S-LCC equivalent input impedance presents a pure resistive moment;

[0029] Calculate the S-LCC output power expression based on the second compensation inductor and the second mutual inductance value, and the second mutual inductance value is determined according to the coupling coefficient;

[0030] Conduct topological coupling analysis according to the coupling coefficient, the LCC-S output power expression and the S-LCC output power expression to obtain the total circuit output power expression;

[0031] Conduct derivative analysis on the coupling coefficient based on the total circuit output power expression, and conduct output power fluctuation analysis according to the preset coupling range to obtain the power fluctuation expression.

[0032] The second aspect of the present application provides a device for designing the parameters of an anti-offset detuned wireless power transfer hybrid compensation network. The device is implemented based on a hybrid compensation circuit, and the hybrid compensation circuit includes: an inverter circuit, a hybrid compensation network and a rectifier circuit;

[0033] The inverter circuit includes two arms composed of 4 MOSFET switching tubes;

[0034] The hybrid compensation network includes a primary compensation network and a secondary compensation network, and is divided into an LCC-S topological network and an S-LCC topological network according to the topological structure;

[0035] The rectifier circuit includes two bridge arms composed of four symmetric diodes;

[0036] The hybrid compensation network is connected in parallel with the transmitting end of the inverter circuit and in series with the receiving end of the rectifier circuit;

[0037] The device includes:

[0038] A circuit equivalent unit for analyzing the hybrid compensation circuit by using the fundamental wave approximation method to obtain a hybrid compensation equivalent circuit, where the hybrid compensation equivalent circuit includes an LCC-S equivalent loop and an S-LCC equivalent loop;

[0039] A detuning analysis unit for introducing a detuning coefficient to perform detuning simplification analysis on the LCC-S equivalent loop and constructing an LCC-S tuning parameter expression formula, where the LCC-S tuning parameter expression formula includes an LCC-S output power expression and an LCC-S extreme mutual inductance value expression;

[0040] A coefficient design unit for selecting, by adjusting the detuning coefficient, the detuning coefficient corresponding to the LCC-S mutual inductance value obtained when the derivative of the LCC-S output power is 0 based on the LCC-S output power expression and the LCC-S extreme mutual inductance value expression as the target detuning coefficient;

[0041] A condition analysis unit for performing a mathematical analysis of the detuning conditions on the LCC-S equivalent loop and the S-LCC equivalent loop according to the detuning parameter and the coupling coefficient to generate a total circuit output power expression and a power fluctuation expression;

[0042] A parameter determination unit for performing an optimization calculation based on the total circuit output power expression and the power fluctuation expression with the goal of minimizing the power fluctuation to obtain the target detuning parameter.

[0043] Preferably, the primary compensation network and the secondary compensation network in the hybrid compensation network are connected in a cascaded manner of double compensation topology, and an LCC-S topology network and an S-LCC topology network are generated in the topological structure form of primary compensation in parallel and secondary compensation in series;

[0044] The LCC-S topology network includes a first compensation inductor and three first compensation capacitors, and the output voltage of the LCC-S topology network is inversely proportional to the offset;

[0045] The S-LCC topology network includes a second compensation inductor and three second compensation capacitors, and the output voltage of the S-LCC topology network is directly proportional to the offset.

[0046] Preferably, the detuning analysis unit is specifically used for:

[0047] Introduce the detuning coefficient, conduct detuning simplification analysis on the LCC-S equivalent circuit, and obtain the expression of the LCC-S equivalent input impedance;

[0048] Analyze the first compensation inductor at the moment when the LCC-S equivalent input impedance presents pure resistance according to the LCC-S equivalent input impedance expression;

[0049] Calculate the LCC-S output power expression based on the first compensation inductor and the first mutual inductance value;

[0050] Conduct mutual inductance derivative analysis according to the LCC-S output power expression to obtain the LCC-S extreme mutual inductance value expression.

[0051] Preferably, the condition analysis unit is specifically configured to:

[0052] Calculate the S-LCC equivalent input impedance when the LCC-S equivalent circuit and the S-LCC equivalent circuit satisfy the preset resonance condition according to the detuning parameter;

[0053] Analyze the second compensation inductor at the moment when the S-LCC equivalent input impedance presents pure resistance;

[0054] Calculate the S-LCC output power expression based on the second compensation inductor and the second mutual inductance value, and the second mutual inductance value is determined according to the coupling coefficient;

[0055] Conduct topological coupling analysis according to the coupling coefficient, the LCC-S output power expression and the S-LCC output power expression to obtain the total circuit output power expression;

[0056] Conduct derivative analysis on the coupling coefficient based on the total circuit output power expression, and conduct output power fluctuation analysis according to the preset coupling range to obtain the power fluctuation expression.

[0057] The third aspect of this application provides a device for designing parameters of an anti-offset detuned wireless power transmission hybrid compensation network, and the device includes a processor and a memory;

[0058] The memory is used to store program codes and transmit the program codes to the processor;

[0059] The processor is used to execute the method for designing parameters of the anti-offset detuned wireless power transmission hybrid compensation network described in the first aspect according to the instructions in the program codes.

[0060] It can be seen from the above technical solutions that the embodiments of this application have the following advantages:

[0061] In this application, a method for designing the parameters of a hybrid compensation network for anti-offset detuned wireless power transfer is provided. The method is implemented based on a hybrid compensation circuit, which includes an inverter circuit, a hybrid compensation network, and a rectifier circuit. The inverter circuit includes two arms composed of four MOSFET switches. The hybrid compensation network includes a primary compensation network and a secondary compensation network, which are divided into an LCC-S topology network and an S-LCC topology network according to the topological structure. The rectifier circuit includes two arms composed of four symmetric diodes. The hybrid compensation network is connected in parallel with the transmitting end of the inverter circuit and in series with the receiving end of the rectifier circuit.

[0062] The method includes: analyzing the hybrid compensation circuit using the fundamental wave approximation method to obtain a hybrid compensation equivalent circuit, which includes an LCC-S equivalent loop and an S-LCC equivalent loop; introducing a detuning coefficient, performing detuning simplification analysis on the LCC-S equivalent loop, and constructing an LCC-S tuning parameter expression formula, which includes an LCC-S output power expression formula and an LCC-S extreme mutual inductance value expression formula; by adjusting the detuning coefficient, selecting the detuning coefficient corresponding to the LCC-S mutual inductance value obtained when the derivative of the LCC-S output power is 0 as the target detuning coefficient based on the LCC-S output power expression formula and the LCC-S extreme mutual inductance value expression formula; performing mathematical analysis of the detuning conditions on the LCC-S equivalent loop and the S-LCC equivalent loop according to the detuning parameters and the coupling coefficient to generate a total circuit output power expression formula and a power fluctuation expression formula; aiming at minimizing the power fluctuation, performing optimization calculations according to the total circuit output power expression formula and the power fluctuation expression formula to obtain the target detuning parameters.

[0063] The method for designing the parameters of the hybrid compensation network for anti-offset detuned wireless power transfer provided in this application introduces the detuning coefficient into the hybrid topology circuit with anti-offset ability, that is, the hybrid compensation circuit. The LCC-S topology network and the S-LCC topology network in the hybrid compensation network can smooth the voltage fluctuation of the output when the system is offset, realizing system anti-offset. In the specific parameter design process, detuning conditions are set for the topological structure and the detuning coefficient is introduced, so as to realize the mathematical analysis of the system under detuning conditions, and optimize the detuning coefficient and detuning parameters based on some power flow parameter requirements for the stable operation of the system, and continuously adjust the detuning coefficient to obtain the target detuning coefficient and parameters. This process fully considers the influence of detuning on the system output, can ensure that the system can still maintain a stable output under detuning conditions, and improves the anti-offset ability of the system. Therefore, this application can solve the technical problem that the existing hybrid topology parameter design depends on the resonant state of the system, cannot control the output fluctuation under detuning conditions, and results in weak anti-offset ability of the system. Brief Description of the Drawings

[0064] Figure 1Schematic diagram of the hybrid compensation circuit structure for a method of designing parameters of an anti-offset detuned wireless power transfer hybrid compensation network provided by an embodiment of the present application;

[0065] Figure 2 Schematic diagram of the flow of a method of designing parameters of an anti-offset detuned wireless power transfer hybrid compensation network provided by an embodiment of the present application;

[0066] Figure 3 Schematic diagram of the equivalent circuit structure of the hybrid compensation corresponding to the hybrid compensation circuit provided by an embodiment of the present application;

[0067] Figure 4 Schematic diagram of the circuit structure after simplifying the LCC-S equivalent circuit provided by an embodiment of the present application;

[0068] Figure 5 Schematic diagram of the circuit structure after simplifying the S-LCC equivalent circuit provided by an embodiment of the present application;

[0069] Figure 6 Schematic diagram of the relationship curve between the total output power of the system and the coupling coefficient provided by an embodiment of the present application Figure 1 ;

[0070] Figure 7 Schematic diagram of the relationship curve between the total output power of the system and the coupling coefficient provided by an embodiment of the present application Figure 2 ;

[0071] Figure 8 Schematic diagram of the relationship curve between the total output power of the system and the coupling coefficient provided by an embodiment of the present application Figure 3 ;

[0072] Figure 9 Schematic diagram of the simulated voltage and current waveforms of the hybrid compensation system under rated operating conditions provided by an application example;

[0073] Figure 10 Schematic diagram of the structure of an anti-offset detuned wireless power transfer hybrid compensation network parameter design device provided by an embodiment of the present application. Detailed implementation manners

[0074] In order to enable those skilled in the art to better understand the solution of the present application, the technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present application without creative efforts shall fall within the protection scope of the present application.

[0075] For ease of understanding, please refer to Figure 1, An embodiment of a method for designing parameters of a hybrid compensation network for anti-offset detuned wireless power transfer provided by this application. The method is implemented based on a hybrid compensation circuit, which includes an inverter circuit, a hybrid compensation network, and a rectifier circuit.

[0076] The inverter circuit includes two arms formed by 4 MOSFET switches.

[0077] The hybrid compensation network includes a primary compensation network and a secondary compensation network, which are divided into an LCC-S topology network and an S-LCC topology network according to the topological structure.

[0078] The rectifier circuit includes two arms formed by 4 symmetric diodes.

[0079] The hybrid compensation network is connected in parallel with the transmitting end of the inverter circuit and in series with the receiving end of the rectifier circuit.

[0080] Further, the first MOSFET switch and the second MOSFET switch in the inverter circuit form the first arm.

[0081] The third MOSFET switch and the fourth MOSFET switch form the second arm.

[0082] Further, the primary compensation network and the secondary compensation network in the hybrid compensation network are connected in a cascaded manner of double compensation topology, and the LCC-S topology network and the S-LCC topology network are generated in the topological structure form of primary compensation in parallel and secondary compensation in series.

[0083] The LCC-S topology network includes a first compensation inductor and three first compensation capacitors, and the output voltage of the LCC-S topology network is inversely proportional to the offset.

[0084] The S-LCC topology network includes a second compensation inductor and three second compensation capacitors, and the output voltage of the S-LCC topology network is directly proportional to the offset.

[0085] It should be noted that the detuning parameter design method of this embodiment is implemented in the LCC-S and S-LCC topology circuits of the wireless power transfer system, that is, the hybrid compensation circuit. The circuit topological structure includes a DC power supply, an inverter circuit, a transmitting end compensation network, a transmitting and receiving coil, a receiving end compensation network, a rectifier circuit, an output filter capacitor, and a load. Among them, the DC power supply is connected in series with the inverter circuit. The inverter circuit is composed of the first MOSFET switch and the second MOSFET switch forming the first arm; the third MOSFET switch and the fourth MOSFET switch form the second arm. And the hybrid compensation network is connected in a cascaded manner of double compensation topology.

[0086] Described from the perspective of the compensation network, the hybrid compensation network includes a primary-side compensation network and a secondary-side compensation network. The primary side is the compensation network of the transmitting end, and the secondary side is the compensation network of the receiving end. Moreover, the compensation at the transmitting end is in parallel, and the compensation at the receiving end is in series. If described from the perspective of the topological structure, the hybrid compensation network can be divided into the upper LCC-S topological network and the lower S-LCC topological network. Whether it is the upper or lower topological network, it can be divided into a transmitting end and a receiving end, which are connected to each other through a transmitting coil and a receiving coil. The overall hybrid compensation network is in parallel with the transmitting end of the inverter circuit and in series with the receiving end of the rectifier circuit.

[0087] Specifically, the transmitting-end compensation network and the receiving-end compensation network of the LCC-S topological network include a first compensation inductor and three first compensation capacitors , , . The first compensation capacitor is in the receiving-end compensation network. The transmitting-end compensation network and the receiving-end compensation network of the S-LCC topological network include a second compensation inductor and three second compensation capacitors , , . The second compensation capacitor is in the transmitting-end compensation network.

[0088] The rectifier circuit is composed of 4 symmetric fast-recovery diodes. Similarly, by connecting two diodes into a bridge arm respectively, two bridge arms are generated. After rectification by the rectifier circuit, it is supplied to the load through the output filter capacitor . In addition, in the hybrid compensation topology composed of the LCC-S topological network and the S-LCC topological network, the output voltage of the LCC-S topological network is inversely proportional to the offset, and the output voltage of the S-LCC topological network is directly proportional to the offset; it can smooth the voltage fluctuation of the output when the system has an offset and achieve anti-offset of the system.

[0089] It should be noted that in this embodiment, before designing the detuning parameters based on the above topological circuit structure, it is assumed that all devices are ideal devices, and stray parameters and internal resistance are assumed not to exist; neither the transmitting nor the receiving end reaches the quasi-resonant state.

[0090] Please refer to Figure 2 . The method includes:

[0091] Step 101: Analyze the hybrid compensation circuit using the fundamental wave approximation method to obtain the hybrid compensation equivalent circuit, which includes an LCC-S equivalent loop and an S-LCC equivalent loop.

[0092] Please refer toFigure 3 , based on the filtering characteristics of the compensation network topology, this embodiment uses the fundamental wave approximation method to simplify and analyze the hybrid compensation circuit proposed above, and a hybrid compensation equivalent circuit can be obtained. It can be found that Figure 3 the hybrid compensation equivalent circuit in can be divided into two loops: the LCC-S equivalent loop and the S-LCC equivalent loop. Among them, the output of the LCC-S equivalent loop is ; the output of the S-LCC equivalent loop is ; the output of the equivalent loop of the entire system can be expressed as

[0093] Step 102: Introduce a detuning coefficient, perform detuning and simplification analysis on the LCC-S equivalent loop, and construct an LCC-S tuning parameter expression formula, which includes an LCC-S output power expression formula and an LCC-S extreme mutual inductance value expression formula.

[0094] Further, step 102 includes:

[0095] Introduce a detuning coefficient, perform detuning and simplification analysis on the LCC-S equivalent loop, and obtain an LCC-S equivalent input impedance expression formula;

[0096] Analyze the first compensation inductor when the LCC-S equivalent input impedance presents a pure resistive moment according to the LCC-S equivalent input impedance expression formula;

[0097] Calculate the LCC-S output power expression formula based on the first compensation inductor and the first mutual inductance value;

[0098] Perform mutual inductance derivative analysis according to the LCC-S output power expression formula, and obtain an LCC-S extreme mutual inductance value expression formula.

[0099] Step 103: By adjusting the detuning coefficient, select the detuning coefficient corresponding to the LCC-S mutual inductance value obtained when the derivative value of the LCC-S output power is 0 as the target detuning coefficient based on the LCC-S output power expression formula and the LCC-S extreme mutual inductance value expression formula.

[0100] It should be noted that in this embodiment, a detuning coefficient is introduced on the receiving side of the LCC-S equivalent loop, and is denoted as the inductance and the capacitor when they are in complete resonance, the standard capacitance value of the capacitor , then on the receiving side there is:

[0101]

[0102] Among them, is the resonant frequency. The detuning parameter after introducing the detuning coefficient is expressed as:

[0103]

[0104] To simplify the calculation and analysis, based on the mutual inductance theory, the inductance and capacitance in the LCC-S equivalent circuit are equivalent to a short circuit. At the same time, the inductance and capacitance are equivalent to . With such simplification, the simplified equivalent circuit Figure 4 can be obtained. Based on this circuit topology, the resonance condition of the LCC-S loop can be obtained:

[0105]

[0106]

[0107] At this time, the equivalent impedance of the receiving end referred to the transmitting end is expressed as:

[0108]

[0109] where is the mutual inductance value of the LCC-S equivalent circuit and can be denoted as the first mutual inductance value; is the load of the LCC-S equivalent circuit. At this time, the capacitance is in parallel with the equivalent impedance . Assuming the impedance of their parallel connection is expressed as , then the equivalent input impedance of the system is expressed as:

[0110]

[0111] Then the overall input equivalent impedance of the LCC-S equivalent circuit region, that is, the expression of the LCC-S equivalent input impedance is:

[0112]

[0113] To ensure that the equivalent input impedance of the LCC-S equivalent circuit, that is, the LCC-S equivalent input impedance is purely resistive, it is necessary to satisfy:

[0114]

[0115] Then based on the above formula, the first compensation inductor can be obtained:

[0116]

[0117] According to the series-parallel relationship of each branch, it is not difficult to determine the current value of each branch:

[0118]

[0119]

[0120]

[0121] in, is the resonant frequency, is the input voltage of the LCC-S equivalent circuit. Then the output power of the LCC-S equivalent circuit can be expressed by the LCC-S output power expression:

[0122]

[0123] Based on the above formula, the first mutual inductance value Take the derivative and set it to 0:

[0124]

[0125] Then the expression of LCC-S extreme mutual inductance corresponding to the maximum output power of LCC-S is:

[0126]

[0127] That is, the extreme mutual inductance value corresponding to the moment when the output power is the extreme value. This embodiment takes this as the goal of optimizing the detuning coefficient, that is, adjusting the detuning coefficient , so that when the system's LCC-S is at maximum output power, the first mutual inductance value of the LCC-S loop Can reach extreme mutual inductance value That is, the detuning coefficient at this time is the target detuning coefficient of the hybrid topology structure to be designed.

[0128] Step 104: Perform mathematical analysis of detuning conditions on the LCC-S equivalent circuit and the S-LCC equivalent circuit according to the detuning parameter and the coupling coefficient, and generate a circuit total output power expression and a power fluctuation expression.

[0129] Furthermore, step 104 includes:

[0130] Calculate the S-LCC equivalent input impedance when the LCC-S equivalent circuit and the S-LCC equivalent circuit meet the preset resonance condition according to the detuning parameters;

[0131] Analyze the second compensation inductance when the S-LCC equivalent input impedance is purely resistive;

[0132] Calculate the S-LCC output power expression based on the second compensation inductor and the second mutual inductance value, where the second mutual inductance value is determined according to the coupling coefficient;

[0133] Conduct topological coupling analysis according to the coupling coefficient, the LCC-S output power expression, and the S-LCC output power expression to obtain the total circuit output power expression;

[0134] Perform derivative analysis on the coupling coefficient based on the total circuit output power expression, and conduct output power fluctuation analysis according to the preset coupling range to obtain the power fluctuation expression.

[0135] Step 105: Taking the minimum power fluctuation as the goal, perform optimization calculation according to the total circuit output power expression and the power fluctuation expression to obtain the target detuning parameter.

[0136] It should be noted that after analyzing the LCC-S topology network, the same circuit simplification and equivalent analysis can be performed on the S-LCC topology network. Please refer to Figure 5 , regard the inductor and the capacitor as short circuits, and at the same time, the inductor and the capacitor are equivalent to , then the preset resonance condition at the receiving end of the S-LCC equivalent loop can be expressed as:

[0137]

[0138]

[0139] At the same time, in order to make the input of the S-LCC equivalent loop present a pure resistive property, the primary side emission network should also present a pure resistive property, so its preset resonance condition should be satisfied:

[0140]

[0141] When the compensation network at the receiving end is in the tuned state, the secondary side equivalent impedance is expressed as:

[0142]

[0143] If the impedance on the secondary side is equivalent to the primary side, then the S-LCC equivalent input impedance is expressed as:

[0144]

[0145] Among them, is the mutual inductance value of the S-LCC equivalent loop, that is, the second mutual inductance value.

[0146] To ensure that the S-LCC equivalent input impedance of the S-LCC equivalent circuit presents pure resistance, the following conditions need to be met:

[0147]

[0148] Then the second compensation inductor can be obtained Expressed as:

[0149]

[0150] According to the series-parallel relationships of each branch, the current values of each branch can be determined:

[0151]

[0152]

[0153]

[0154] From this, the output power expression of the S-LCC equivalent circuit can be obtained, that is, the S-LCC output power expression:

[0155]

[0156] Since the parameter design purpose of this embodiment is to ensure the stability of the total system output power within a certain range of the coupling coefficient of the system, that is, the total circuit output power The volatility within the preset coupling range reaches the minimum. The preset coupling range of this embodiment is expressed as , and , where is the proportionality coefficient, , are respectively the minimum and maximum values of the value range of the coupling coefficient, which can be set according to the actual situation and are not limited here. , respectively represent the total system output power corresponding to the extreme values of the coupling coefficient of the system. The relationship between the total system output power and the coupling coefficient is respectively as shown in Figure 6 , 7 , 8.

[0157] If is any coupling coefficient value within the preset coupling range, it is not difficult to compare and see from Figure 6 , 7 , 8 that Figure 7 when the total system output power has the minimum volatility, that is:

[0158] When Total output power of the system at this time When the volatility is the smallest, there is:

[0159]

[0160] Then, combining the above formula with , the power fluctuation expression can be obtained:

[0161]

[0162] Among them, represents the output power volatility.

[0163] From the analysis of the entire hybrid equivalent circuit, in order to minimize the fluctuation of the system output power within a certain coupling coefficient range, this embodiment will configure an appropriate coupling coefficient K. Based on the coupling coefficient, the first mutual inductance value and the second mutual inductance value can be expressed as:

[0164]

[0165]

[0166]

[0167] Among them, the last formula is the linear relationship between the first mutual inductance value and the second mutual inductance value . , are proportional parameters determined by the mutual inductance coils actually used in the two circuits respectively, and the specific values are determined according to the actual coil situation. , are the coupling coefficients of the LCC-S equivalent circuit and the S-LCC equivalent circuit respectively; , are parameters determined by the mutual inductance coils in the two circuits, and are specifically determined according to the coil situation; the coupling mechanism of this embodiment uses a DDQ combined coil. Combining the LCC-S output power expression and the S-LCC output power expression calculated in the analysis of the LCC-S and S-LCC equivalent circuits, and the first mutual inductance value and the second mutual inductance value solved according to the coupling coefficient, the relationship between the output powers of the two circuits and the coupling coefficient can be obtained:

[0168]

[0169]

[0170] Two circuit topologies are connected in series at the receiving end, so the total output power of the circuit can be expressed as:

[0171]

[0172] Let the total output power Derive with respect to the coupling coefficient and set the derivative to 0:

[0173]

[0174] At this time, the LCC-S coupling coefficient corresponding to the maximum total output power can be obtained :

[0175]

[0176] The double compensation network channels are connected in parallel and commonly connected to the output end of the inverter circuit, as Figure 3 shown. The output voltage of the inverter circuit is a square wave, which can be expressed by Fourier decomposition as:

[0177]

[0178] The equivalent resistance of each receiving-end compensation circuit can be expressed as:

[0179]

[0180] According to Ohm's law and combining the above formula, the voltage before the input rectifier circuit of each channel can be obtained:

[0181]

[0182] It can be seen from the above formula that the output voltage of the LCC-S compensation topology of Channel 1 is proportional to the mutual inductance, that is, when the offset of the receiving-end coil increases, as the mutual inductance decreases, the output voltage also decreases; the output voltage of the S-LCC compensation topology of Channel 2 is inversely proportional to the mutual inductance, that is, when the offset of the receiving-end coil increases, as the mutual inductance decreases, the output voltage will increase. The two channels are connected in series at the receiving end, and the input voltage of the rectifier circuit can be expressed as:

[0183]

[0184] Considering the fundamental voltage component, the relationship between the input voltage and the output voltage of the rectifier circuit can be expressed as:

[0185]

[0186] Combined formula Formula, Combining the formula, this formula above, the DC output voltage of the rectifier circuit at the receiving end can be obtained as:

[0187]

[0188] Wherein, is the input voltage of the inverter circuit, is the total DC output voltage of the rectifier circuit at the receiving end of the system.

[0189] It can be seen from the above formula that the voltage gain of the system is:

[0190]

[0191] According to this voltage gain formula, the connection between the two compensation networks can be established. If the detuning coefficient A is finally determined, after setting the voltage gain the specific mutual inductance coefficient can be calculated according to this formula.

[0192] According to Figure 7 it can be known that within the preset coupling range, the output power fluctuation rate generated by the system can be made smaller. Taking the minimum output power fluctuation rate of the system as the goal, the above-layer calculation formulas can be traced back until a suitable detuning parameter is selected, that is, the target detuning parameter. It can be understood that in addition to the detuning parameter can also include other power flow parameters calculated based on the detuning coefficient or the detuning parameter that is, the circuit parameters affected by the detuning coefficient, such as other inductors, capacitors, output voltage, output current, output power, etc. in the compensation network. Here, only examples are given without limitation.

[0193] For the sake of easy understanding, this application proposes a practical application example of the parameter design method for the detuning wireless power transfer hybrid compensation network with anti-offset. For the parameter design index, please refer to Table 1.

[0194] Table 1 Example of system index parameters

[0195]

[0196] Using the iterative optimization method to select the detuning coefficient and the detuning parameter The obtained detuning coefficient The detuning parameter Substitute the obtained detuning coefficient and detuning parameter into the important parameter formula above, and other parameters of the system can be obtained. Please refer to Table 2.

[0197] Table 2 Other parameter values of the circuit system

[0198]

[0199] The system is also simulated under rated operating conditions. For the obtained output voltage and output current, please refer to Figure 9 , and the simulation results show that under the load Yes, the output voltage of the system and the output current remain stable. The output voltage is about 401.36V, and the output current is about 8.28A. The total output power of the circuit is about 3323.3W, all within the required design range, that is, the system realizes stable output based on the designed detuning parameter and detuning coefficient.

[0200] The method for designing the parameters of the anti-offset detuned wireless power transfer hybrid compensation network provided by the embodiment of the present application introduces the detuning coefficient into the hybrid topology circuit with anti-offset ability, that is, the hybrid compensation circuit; the LCC-S topology network and the S-LCC topology network in the hybrid compensation network can smooth the voltage fluctuation of the output when the system offset occurs, realizing system anti-offset. In the specific parameter design process, detuning conditions are set for the topology structure and the detuning coefficient is introduced, so as to realize the mathematical analysis of the system under detuning conditions, and optimize the detuning coefficient and detuning parameter based on some power flow parameter requirements for the stable operation of the system, and continuously adjust the detuning coefficient to obtain the target detuning coefficient and parameter; this process fully considers the influence of detuning on the system output, can ensure that the system can still maintain stable output under detuning conditions, and improves the anti-offset ability of the system. Therefore, the embodiment of the present application can solve the technical problem that the existing hybrid topology parameter design depends on the resonant state of the system, cannot control the output fluctuation under detuning conditions, and results in weak anti-offset ability of the system.

[0201] For easy understanding, please refer to Figure 10 , the present application provides an embodiment of a device for designing the parameters of an anti-offset detuned wireless power transfer hybrid compensation network. The device is implemented based on a hybrid compensation circuit, and the hybrid compensation circuit includes: an inverter circuit, a hybrid compensation network, and a rectifier circuit;

[0202] The inverter circuit includes 2 arms composed of 4 MOSFET switches;

[0203] The hybrid compensation network includes a primary compensation network and a secondary compensation network, which are divided into an LCC-S topology network and an S-LCC topology network according to the topology structure;

[0204] The rectifier circuit includes two bridge arms composed of four symmetric diodes;

[0205] The hybrid compensation network is connected in parallel with the transmitting end of the inverter circuit and in series with the receiving end of the rectifier circuit;

[0206] The device includes:

[0207] The circuit equivalent unit 201 is used to analyze the hybrid compensation circuit by using the fundamental wave approximation method to obtain the hybrid compensation equivalent circuit, and the hybrid compensation equivalent circuit includes an LCC-S equivalent loop and an S-LCC equivalent loop;

[0208] The detuning analysis unit 202 is used to introduce a detuning coefficient, perform detuning simplification analysis on the LCC-S equivalent loop, and construct an LCC-S tuning parameter expression formula, and the LCC-S tuning parameter expression formula includes an LCC-S output power expression formula and an LCC-S extreme mutual inductance value expression formula;

[0209] The coefficient design unit 203 is used to select the detuning coefficient corresponding to the LCC-S mutual inductance value obtained when the derivative value of the LCC-S output power is 0 as the target detuning coefficient based on the LCC-S output power expression formula and the LCC-S extreme mutual inductance value expression formula by adjusting the detuning coefficient;

[0210] The condition analysis unit 204 is used to perform mathematical analysis on the detuning conditions of the LCC-S equivalent loop and the S-LCC equivalent loop according to the detuning parameter and the coupling coefficient, and generate a total circuit output power expression formula and a power fluctuation expression formula;

[0211] The parameter determination unit 205 is used to perform optimization calculations based on the total circuit output power expression formula and the power fluctuation expression formula with the goal of minimizing power fluctuation to obtain the target detuning parameter.

[0212] Furthermore, the primary compensation network and the secondary compensation network in the hybrid compensation network are connected in a cascaded manner of double compensation topology, and an LCC-S topology network and an S-LCC topology network are generated in the topological structure form of primary compensation in parallel and secondary compensation in series;

[0213] The LCC-S topology network includes a first compensation inductor and three first compensation capacitors, and the output voltage of the LCC-S topology network is inversely proportional to the offset;

[0214] The S-LCC topology network includes a second compensation inductor and three second compensation capacitors, and the output voltage of the S-LCC topology network is directly proportional to the offset.

[0215] Furthermore, the detuning analysis unit 202 is specifically used for:

[0216] The detuning coefficient is introduced to perform a detuning simplification analysis on the LCC-S equivalent circuit, and the expression of the LCC-S equivalent input impedance is obtained;

[0217] According to the LCC-S equivalent input impedance expression, the first compensation inductor at the moment when the LCC-S equivalent input impedance presents a pure resistive property is analyzed;

[0218] Based on the first compensation inductor and the first mutual inductance value, the LCC-S output power expression is calculated;

[0219] According to the LCC-S output power expression, a derivative analysis of the mutual inductance is performed to obtain the LCC-S extreme mutual inductance value expression.

[0220] Furthermore, the condition analysis unit 204 is specifically configured to:

[0221] According to the detuning parameter, the S-LCC equivalent input impedance when the LCC-S equivalent circuit and the S-LCC equivalent circuit meet the preset resonance condition is calculated;

[0222] The second compensation inductor at the moment when the S-LCC equivalent input impedance presents a pure resistive property is analyzed;

[0223] Based on the second compensation inductor and the second mutual inductance value, the S-LCC output power expression is calculated, and the second mutual inductance value is determined according to the coupling coefficient;

[0224] According to the coupling coefficient, the LCC-S output power expression and the S-LCC output power expression, a topological coupling analysis is performed to obtain the total circuit output power expression;

[0225] Based on the total circuit output power expression, a derivative analysis of the coupling coefficient is performed, and an output power fluctuation analysis is performed according to the preset coupling range to obtain the power fluctuation expression.

[0226] This application also provides a device for designing parameters of an anti-offset detuned wireless power transmission hybrid compensation network. The device includes a processor and a memory;

[0227] The memory is used to store program codes and transmit the program codes to the processor;

[0228] The processor is configured to execute the method for designing parameters of an anti-offset detuned wireless power transmission hybrid compensation network in the above method embodiment according to the instructions in the program codes.

[0229] In several embodiments provided by the present application, it should be understood that the disclosed devices and methods can be implemented in other ways. For example, the device embodiments described above are merely illustrative. For example, the division of the units is only a logical function division. In actual implementation, there may be other division methods. For example, multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the displayed or discussed couplings or direct couplings or communication connections between each other can be through some interfaces. The indirect couplings or communication connections of the devices or units can be in electrical, mechanical or other forms.

[0230] The units described as separate components may or may not be physically separated. The components displayed as units may or may not be physical units, that is, they can be located in one place or distributed to multiple network units. Some or all of the units can be selected according to actual needs to achieve the purpose of the solution of this embodiment.

[0231] In addition, in each embodiment of the present application, the functional units can be integrated in a processing unit, or each unit can exist physically alone, or two or more units can be integrated in one unit. The above-mentioned integrated units can be implemented in the form of hardware or in the form of software functional units.

[0232] If the above-mentioned integrated unit is implemented in the form of a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present application, in essence, or the part that contributes to the prior art, or all or part of this technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions for a computer device (which can be a personal computer, a server, or a network device, etc.) to execute all or part of the steps of the methods described in each embodiment of the present application. The foregoing storage medium includes: USB flash drives, mobile hard disks, read-only memories (English full name: Read-Only Memory, English abbreviation: ROM), random access memories (English full name: Random Access Memory, English abbreviation: RAM), magnetic disks or optical discs and other various media that can store program codes.

[0233] As described above, the above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit it; although the present application has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that: they can still modify the technical solutions described in the foregoing embodiments, or perform equivalent replacements on some of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the various embodiments of the present application.

Claims

1. A method for designing parameters of a hybrid compensation network for detuned wireless power transmission with anti-drift, characterized in that: The method is implemented based on a hybrid compensation circuit, which includes: an inverter circuit, a hybrid compensation network and a rectifier circuit; The inverter circuit includes two bridge arms formed by four MOSFET switch tubes; The hybrid compensation network includes a primary compensation network and a secondary compensation network, which are divided into an LCC-S topology network and an S-LCC topology network according to the topology structure; The rectifier circuit includes two bridge arms formed by four symmetrical diodes; The hybrid compensation network is connected in parallel with the transmitting end of the inverter circuit and in series with the receiving end of the rectifier circuit; The method comprises: The hybrid compensation circuit is analyzed by using a fundamental wave approximation method to obtain a hybrid compensation equivalent circuit, wherein the hybrid compensation equivalent circuit includes an LCC-S equivalent circuit and an S-LCC equivalent circuit; The detuning coefficient is introduced to simplify the detuning analysis of the LCC-S equivalent circuit, and the LCC-S tuning parameter expression formula is constructed. The LCC-S tuning parameter expression formula includes the LCC-S output power expression and the LCC-S extreme mutual inductance value expression. The specific process is as follows: The detuning coefficient is introduced to perform a detuning simplified analysis on the LCC-S equivalent circuit, and an expression for the LCC-S equivalent input impedance is obtained; Analyze the first compensation inductance when the LCC-S equivalent input impedance presents pure resistance according to the LCC-S equivalent input impedance expression; Calculating an LCC-S output power expression according to the first compensation inductance and the first mutual inductance value; Perform mutual inductance derivation analysis based on the LCC-S output power expression to obtain the LCC-S extreme mutual inductance value expression; By adjusting the detuning coefficient, based on the LCC-S output power expression and the LCC-S extreme mutual inductance expression, the detuning coefficient corresponding to the LCC-S mutual inductance value obtained when the LCC-S output power derivative value is 0 is selected as the target detuning coefficient; Performing mathematical analysis of detuning conditions on the LCC-S equivalent circuit and the S-LCC equivalent circuit according to the detuning parameter and the coupling coefficient, generating a circuit total output power expression and a power fluctuation expression; With the goal of minimizing power fluctuation, an optimization calculation is performed based on the total output power expression of the circuit and the power fluctuation expression to obtain a target detuning parameter.

2. The method for designing parameters of a hybrid compensation network for detuned wireless power transmission with anti-drift according to claim 1, characterized in that: The first MOSFET switch tube and the second MOSFET switch tube in the inverter circuit form a first bridge arm; The third MOSFET switch tube and the fourth MOSFET switch tube form a second bridge arm.

3. The method for designing parameters of a hybrid compensation network for detuned wireless power transmission with anti-deviation according to claim 1, characterized in that: The primary compensation network and the secondary compensation network in the hybrid compensation network are connected in a dual compensation topology cascade manner, and an LCC-S topology network and an S-LCC topology network are generated in a topology structure in which the primary compensation is in parallel and the secondary compensation is in series. The LCC-S topology network includes a first compensation inductor and three first compensation capacitors, and the output voltage of the LCC-S topology network is inversely proportional to the offset; The S-LCC topology network includes a second compensation inductor and three second compensation capacitors, and the output voltage of the S-LCC topology network is proportional to the offset.

4. The method for designing parameters of a hybrid compensation network for detuned wireless power transmission with anti-deviation according to claim 1, characterized in that: The method of performing a mathematical analysis of detuning conditions on the LCC-S equivalent circuit and the S-LCC equivalent circuit according to the detuning parameter and the coupling coefficient to generate a circuit total output power expression and a power fluctuation expression includes: Calculating the S-LCC equivalent input impedance when the LCC-S equivalent circuit and the S-LCC equivalent circuit meet a preset resonance condition according to the detuning parameter; Analyze the second compensation inductance when the S-LCC equivalent input impedance presents pure resistance; Calculating an S-LCC output power expression according to the second compensation inductance and the second mutual inductance value, wherein the second mutual inductance value is determined according to a coupling coefficient; Perform a topological coupling analysis based on the coupling coefficient, the LCC-S output power expression, and the S-LCC output power expression to obtain a total output power expression of the circuit; The coupling coefficient is derived and analyzed based on the total output power expression of the circuit, and the output power fluctuation analysis is performed according to a preset coupling range to obtain a power fluctuation expression.

5. A device for designing parameters of a hybrid compensation network for detuned wireless power transmission with anti-deviation, characterized in that: The device is implemented based on a hybrid compensation circuit, which includes: an inverter circuit, a hybrid compensation network and a rectifier circuit; The inverter circuit includes two bridge arms formed by four MOSFET switch tubes; The hybrid compensation network includes a primary compensation network and a secondary compensation network, which are divided into an LCC-S topology network and an S-LCC topology network according to the topology structure; The rectifier circuit includes two bridge arms formed by four symmetrical diodes; The hybrid compensation network is connected in parallel with the transmitting end of the inverter circuit and in series with the receiving end of the rectifier circuit; The device comprises: A circuit equivalent unit, used for analyzing the hybrid compensation circuit by adopting a fundamental wave approximation method to obtain a hybrid compensation equivalent circuit, wherein the hybrid compensation equivalent circuit includes an LCC-S equivalent circuit and an S-LCC equivalent circuit; The detuning analysis unit is used to introduce a detuning coefficient, perform a detuning simplified analysis on the LCC-S equivalent circuit, and construct an LCC-S tuning parameter expression formula, wherein the LCC-S tuning parameter expression formula includes an LCC-S output power expression and an LCC-S extreme mutual inductance value expression. The detuning analysis unit is specifically used to: The detuning coefficient is introduced to perform a detuning simplified analysis on the LCC-S equivalent circuit, and an expression for the LCC-S equivalent input impedance is obtained; Analyze the first compensation inductance when the LCC-S equivalent input impedance presents pure resistance according to the LCC-S equivalent input impedance expression; Calculating an LCC-S output power expression according to the first compensation inductance and the first mutual inductance value; Perform mutual inductance derivation analysis based on the LCC-S output power expression to obtain the LCC-S extreme mutual inductance value expression; A coefficient design unit, configured to select, by adjusting the detuning coefficient, a detuning coefficient corresponding to the LCC-S mutual inductance value obtained when the LCC-S output power derivative value is 0 as a target detuning coefficient based on the LCC-S output power expression and the LCC-S extreme mutual inductance value expression; A conditional analysis unit, used for performing a detuning condition mathematical analysis on the LCC-S equivalent circuit and the S-LCC equivalent circuit according to the detuning parameter and the coupling coefficient, and generating a circuit total output power expression and a power fluctuation expression; The parameter determination unit is used to optimize and calculate the target detuning parameter according to the total output power expression of the circuit and the power fluctuation expression with the goal of minimizing the power fluctuation.

6. The device for designing parameters of a hybrid compensation network for detuned wireless power transmission with anti-deviation according to claim 5, characterized in that: The primary compensation network and the secondary compensation network in the hybrid compensation network are connected in a dual compensation topology cascade manner, and an LCC-S topology network and an S-LCC topology network are generated in a topology structure in which the primary compensation is in parallel and the secondary compensation is in series. The LCC-S topology network includes a first compensation inductor and three first compensation capacitors, and the output voltage of the LCC-S topology network is inversely proportional to the offset; The S-LCC topology network includes a second compensation inductor and three second compensation capacitors, and the output voltage of the S-LCC topology network is proportional to the offset.

7. The device for designing parameters of a hybrid compensation network for detuned wireless power transmission with anti-deviation according to claim 5, characterized in that: The condition analysis unit is specifically used for: Calculating the S-LCC equivalent input impedance when the LCC-S equivalent circuit and the S-LCC equivalent circuit meet a preset resonance condition according to the detuning parameter; Analyze the second compensation inductance when the S-LCC equivalent input impedance presents pure resistance; Calculating an S-LCC output power expression according to the second compensation inductance and the second mutual inductance value, wherein the second mutual inductance value is determined according to a coupling coefficient; Perform topological coupling analysis according to the coupling coefficient, the LCC-S output power expression and the S-LCC output power expression to obtain a total output power expression of the circuit; The coupling coefficient is derived and analyzed based on the total output power expression of the circuit, and the output power fluctuation analysis is performed according to a preset coupling range to obtain a power fluctuation expression.

8. A device for designing parameters of a hybrid compensation network for detuned wireless power transmission with anti-deviation, characterized in that: The device comprises a processor and a memory; The memory is used to store program code and transmit the program code to the processor; The processor is used to execute the method for designing parameters of a hybrid compensation network for detuned wireless power transmission with resistance to offset according to the instructions in the program code according to any one of claims 1 to 4.

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