System for wirelessly supplying power to temperature sensor in liquid coupling device

Abstract

The invention discloses a system for wirelessly supplying power to a temperature sensor in a liquid coupling device, and belongs to a wireless electric energy transmission device. In the prior art, a wired mode is adopted to supply power to a temperature sensor, wiring is complex, and measurement precision is poor. The control module generates a PWM driving signal according to the actual power supply voltage value of the temperature sensor; a PWM signal with the optimal duty ratio is obtained according to the voltage value and the current value output by the full-bridge inverter circuit and the alternating current coupled by the receiving coil; the DC-DC conversion circuit transmits the converted direct current to the full-bridge inverter circuit according to the PWM driving signal; the full-bridge inverter circuit converts direct current into high-frequency alternating current according to the PWM signal with the preset frequency; the transmitting coil converts the high-frequency alternating current into electromagnetic field energy; the receiving coil converts the received electromagnetic field energy into alternating current electric energy; and the full-bridge active rectification impedance matching circuit converts alternating-current electric energy into direct-current electric energy to supply power to the temperature sensor according to the PWM signal with the optimal duty ratio. The invention is used for wireless power supply.

Description

Technical Field

[0001] The invention relates to the field of wireless power transmission and belongs to a wireless power transmission device. Background Art

[0002] In the modern shipbuilding industry, liquid coupling devices are widely used in ship power transmission units to achieve smooth power transmission and speed regulation. In the actual operation process, due to friction, heat and other reasons, its temperature will continue to rise. If the temperature is too high, it may cause damage to the liquid coupling device and even cause a safety accident.

[0003] In order to ensure the safe and stable operation of the liquid coupling device, it is particularly important to monitor its temperature in real time. Traditional temperature sensors usually use wired power supply, that is, a power supply is set outside the liquid coupling device, a temperature sensor and a power conversion module are set inside the liquid coupling device, and the power supply is connected to the power conversion module inside the liquid coupling device through a cable. The power conversion module is then connected to the temperature sensor through a cable to power the temperature sensor. However, this method of connecting the outside and inside of the liquid coupling device through a cable has certain limitations. First, the wired power transmission method is complicated, and the cable needs to be connected to the power conversion module inside the liquid coupling device, which increases the difficulty of installation and maintenance. Secondly, it is susceptible to interference. The cable is easily affected by electromagnetic interference, which affects the measurement accuracy of the temperature sensor. Finally, the wired transmission method is difficult to maintain. If the cable is damaged, it is necessary to shut down and replace the cable, which affects the normal operation of the entire liquid coupling device.

[0004] Therefore, the existing method of powering the temperature sensor in a wired manner when monitoring the temperature of the liquid coupling device has the problems of complex wiring, poor measurement accuracy, and easy damage of the cable, which affects the normal operation of the liquid coupling device. Summary of the invention

[0005] The purpose of the present invention is to solve the problems of using wired power supply to power the temperature sensor in the existing liquid coupling device for temperature monitoring, which has complex wiring, poor measurement accuracy and easy damage of the cable, affecting the normal operation of the liquid coupling device. A system for wireless power supply to the temperature sensor in the liquid coupling device is proposed.

[0006] A system for wirelessly powering a temperature sensor in a liquid coupling device, the system comprising a power sending module, a power receiving module and a control module;

[0007] The power transmission module is arranged outside the liquid coupling device, and the power receiving module is arranged inside the liquid coupling device; the power transmission module wirelessly supplies power to the power receiving module, and the power receiving module receives power to supply power to the powered temperature sensor;

[0008] The power transmission module includes a DC power supply, a DC-DC conversion circuit, a full-bridge inverter circuit and a transmitting coil;

[0009] The power receiving module includes a receiving coil and a full-bridge active rectification impedance matching circuit;

[0010] A control module, used to generate a corresponding PWM drive signal according to the actual supply voltage value of the powered temperature sensor; and also used to obtain a PWM signal with an optimal duty cycle according to the voltage value and current value output by the full-bridge inverter circuit and the AC power coupled by the receiving coil;

[0011] The DC-DC conversion circuit is used to instruct the received DC power to perform voltage conversion according to the received PWM drive signal, and the converted DC power is transmitted to the full-bridge inverter circuit; the full-bridge inverter circuit, according to the PWM signal of the preset frequency generated by the receiving control module, instructs the received DC power to be converted into high-frequency AC power and transmitted to the transmitting coil;

[0012] The transmitting coil is used to convert the received high-frequency alternating current into electromagnetic field energy and transmit it to the receiving coil;

[0013] The receiving coil is used to convert the received electromagnetic field energy into AC electric energy and transmit it to the full-bridge active rectification impedance matching circuit;

[0014] The full-bridge active rectification impedance matching circuit is used for guiding the received AC power to be converted into DC power to power the temperature sensor according to the received PWM signal with the optimal duty cycle.

[0015] Preferably, the control module includes a sending end MCU controller, a receiving end MCU controller and a WIFI module;

[0016] The MCU controller at the sending end is arranged outside the liquid coupling device, and the MCU controller at the receiving end is arranged inside the liquid coupling device;

[0017] The receiving end MCU controller is used to collect the actual supply voltage value of the powered temperature sensor and send it to the transmitting end MCU controller through the WIFI module; it is also used to collect the AC power coupled by the receiving coil, combine the received RMS value, obtain the PWM signal with the optimal duty cycle, and send it to the full-bridge active rectification impedance matching circuit;

[0018] The MCU controller at the sending end is used to compare the expected voltage value with the actual supply voltage value of the powered temperature sensor, generate a corresponding PWM drive signal, and send it to the DC-DC conversion circuit; it is also used to output a PWM signal of a preset frequency to the full-bridge inverter circuit; it is also used to collect the voltage and current values ​​output by the full-bridge inverter circuit, calculate the root mean square value, and send it to the MCU controller at the receiving end through the WIFI module.

[0019] Preferably, the optimal duty cycle is expressed as:

[0020]

[0021] Where D η-max is the optimal duty cycle value after model calculation, M is the mutual inductance value, R is the internal resistance of the two-terminal coil, R1 is the real-time actual impedance value of the receiving end, and ω is the system operating angular frequency;

[0022] Among them, the mutual inductance value M is expressed as:

[0023]

[0024] Where D is the duty cycle value set for the receiving end output, U in is the output voltage of the transmitter, I in is the output current value of the transmitter.

[0025] Preferably, the DC-DC conversion circuit includes a half-bridge driver chip U1 of model IR2109, resistors R1-R8, IGBT switches S1-S2, an inductor L1, electrolytic capacitors C1-C7 and a diode D1;

[0026] The positive pole of the power supply is connected to the No. 1 pin, No. 3 pin and the anode of the diode D1 of the IR2109 half-bridge driver chip U1 at the same time, the No. 2 pin of the IR2109 half-bridge driver chip U1 is connected to the PWM drive signal output end of the MCU controller at the transmitting end, and the negative pole of the power supply is connected to the No. 4 pin of the IR2109 half-bridge driver chip;

[0027] The cathode of the diode D1 is connected to the No. 8 pin of the IR2109 half-bridge driver chip U1 and the positive electrode of the capacitor C1 at the same time, the negative electrode of the capacitor C1 is connected to the No. 6 pin of the IR2109 half-bridge driver chip U1, the No. 7 pin of the IR2109 half-bridge driver chip U1 is connected to one end of the resistor R1, the other end of the resistor R1 is connected to the gate of the IGBT switch tube S1, the source of the IGBT switch tube S1 is connected to the positive electrode of the electrolytic capacitor C2, the positive electrode of the electrolytic capacitor C3, the positive electrode of the electrolytic capacitor C4 and the positive electrode of the DC power supply at the same time, and the negative electrode of the electrolytic capacitor C2, the negative electrode of the electrolytic capacitor C3, the negative electrode of the electrolytic capacitor C4 and the negative electrode of the DC power supply are all connected to the power ground;

[0028] The drain of IGBT switch tube S1 is simultaneously connected to one end of inductor L1, the source of IGBT switch tube S2, the negative electrode of capacitor C1 and pin 6 of IR2109 half-bridge driver chip U1. The other end of inductor L1 is simultaneously connected to the positive electrode of electrolytic capacitor C5, the positive electrode of electrolytic capacitor C6, the positive electrode of electrolytic capacitor C7, one end of resistor R3 and the positive output end of the DC-DC conversion circuit. The negative output end of the DC-DC conversion circuit is simultaneously connected to the power supply and resistor R 6, the other end of resistor R6, one end of resistor R5, the cathode of electrolytic capacitor C7, the cathode of electrolytic capacitor C6, the cathode of electrolytic capacitor C5 and the drain of IGBT switch tube S2 are all connected to the power ground, the gate of IGBT switch tube S2 is connected to one end of resistor R2, the other end of resistor R2 is connected to pin 5 of IR2109 half-bridge driver chip U1, the other end of resistor R5 is connected to one end of resistor R4, and the other end of resistor R4 is connected to the other end of resistor R3 and the power supply at the same time.

[0029] Preferably, the full-bridge inverter circuit includes resistors R9-R21, capacitors C10-C19 and IGBT switches G1-G4;

[0030] The first PWM signal output end of the MCU controller at the transmitting end is connected to one end of the resistor R10, and the other end of the resistor R10 is simultaneously connected to one end of the resistor R9 and the gate of the IGBT switch tube G1, the source of the IGBT switch tube G1 is simultaneously connected to one end of the capacitor C10, one end of the capacitor C12, one end of the capacitor C13, one end of the capacitor C20, the drain of the IGBT switch tube G3 and the output end of the DC-DC conversion circuit, the drain of the IGBT switch tube G1 is simultaneously connected to the source of the IGBT switch tube G2, one end of the resistor R12, the other end of the resistor R9, one end of the capacitor C11, one end of the capacitor C14, one end of the capacitor C15, one end of the capacitor C16 and one end of the capacitor C17, the other end of the capacitor C14, the other end of the capacitor C15, the other end of the capacitor C16 and the other end of the capacitor C17 are all connected to one AC output end of the transmitting coil; the other end of the resistor R12 is connected to the other end of the capacitor C10;

[0031] The second PWM signal output end of the MCU controller at the sending end is connected to one end of the resistor R11, the other end of the resistor R11 is simultaneously connected to the gate of the IGBT switch tube G2 and one end of the resistor R13, the other end of the resistor R13 is simultaneously connected to one end of the resistor R14, one end of the resistor R21, the drain of the IGBT switch tube G2, one end of the resistor R16, one end of the resistor R18 and the source of the IGBT switch tube G4, and the other end of the resistor R21 is connected to the power ground;

[0032] The other end of the resistor R16 is connected to one end of the capacitor C19, and the other end of the capacitor C19 is simultaneously connected to one end of the resistor R15, the source of the IGBT switch tube G3, the drain of the IGBT switch tube G2, one end of the resistor R17 and the other AC output end of the transmitting coil, the other end of the resistor R15 is connected to the other end of the capacitor C20, the other end of the resistor R17 is simultaneously connected to the gate of the IGBT switch tube G3 and one end of the resistor R19, the other end of the resistor R19 is connected to the third PWM signal output end of the MCU controller at the transmitting end, the other end of the resistor R18 is simultaneously connected to the gate of the IGBT switch tube G4 and one end of the resistor 20, and the other end of the resistor 20 is connected to the fourth PWM signal output end of the MCU controller at the transmitting end.

[0033] Preferably, the full-bridge active rectification impedance matching circuit includes capacitors C21-C24, resistors R22-R29 and IGBT switches Q1-Q4;

[0034] One AC output end of the receiving coil is connected to one end of capacitor C21, one end of capacitor C22 and one end of capacitor C23 at the same time;

[0035] The other end of capacitor C21, the other end of capacitor C22 and the other end of capacitor C23 are all connected to the positive measuring end of the capacitor;

[0036] Another AC output end of the receiving coil is connected to the source of the IGBT switch tube Q4 and the source of the IGBT switch tube Q3 at the same time;

[0037] The first optimal duty cycle PWM signal output end of the receiving end MCU controller is simultaneously connected to one end of the resistor R22 and the gate of the IGBT switch tube Q1, and the drain of the IGBT switch tube Q1 is simultaneously connected to the other end of the resistor R22, the negative electrode measurement end of the capacitor and the source of the IGBT switch tube Q3;

[0038] The third optimal duty cycle PWM signal output end of the receiving end MCU controller is simultaneously connected to one end of the resistor R24 ​​and the gate of the IGBT switch tube Q3, and the drain of the IGBT switch tube Q3 is simultaneously connected to the other end of the resistor R24, one end of the resistor R25, the drain of the IGBT switch tube Q4, the negative electrode of the electrolytic capacitor C24, one end of the resistor R28, one end of the resistor R29, the power ground and the power ground measurement point;

[0039] The second optimal duty cycle PWM signal output end of the receiving end MCU controller is simultaneously connected to one end of resistor R23 and the gate of the IGBT switch tube Q2, the source of the IGBT switch tube Q2 is simultaneously connected to the source of the IGBT switch tube Q1, the positive electrode of the electrolytic capacitor C24, one end of resistor R26 and the positive electrode measurement end of the actual power supply voltage value of the powered temperature sensor, and the negative electrode measurement end of the actual power supply voltage value of the powered temperature sensor is simultaneously connected to the current measurement end and the other end of resistor R29; the other end of resistor R26 is simultaneously connected to one end of resistor R27 and the input end of the temperature sensor, and the other end of resistor R27 is connected to the other end of resistor R28.

[0040] Preferably, both the sending end MCU controller and the receiving end MCU controller are implemented using a chip of model STM32F103VET6.

[0041] Preferably, the WIFI module is implemented using an ESP8266 chip.

[0042] The beneficial effects of the present invention are:

[0043] The DC-DC conversion circuit, full-bridge inverter circuit, transmitting coil and transmitting end MCU controller in the present invention are all arranged outside the liquid coupling device, while the full-bridge active rectification impedance matching circuit, receiving coil, transmitting end MCU controller and temperature sensor are all installed inside the liquid coupling device. The external and internal parts of the liquid coupling device are wirelessly inductively transmitted with the transmitting coil and the receiving coil, and the power supply method is simple.

[0044] The present invention is equipped with a DC-DC conversion circuit to provide a stable power supply for the entire device. Then, the stable direct current is converted into high-frequency alternating current through a full-bridge inverter circuit and transmitted to the coupling coil. The coupling coil is a key part of the wireless power transmission device. The transmitting coil converts the high-frequency alternating current energy into electromagnetic field energy and transmits it to the receiving end. The receiving coil corresponds to the transmitting coil. It receives the electromagnetic field energy transmitted by the transmitting coil and converts it into alternating current energy. Then, the alternating current energy will be converted into direct current energy through a rectifier and filter circuit. The present invention uses a full-bridge diode rectifier circuit as a full-bridge active rectifier impedance matching circuit. The direct current energy is finally supplied to the temperature sensor through a voltage stabilizing circuit.

[0045] The present invention provides a wireless power transmission system. A DC-DC voltage stabilizing circuit is added to the transmitting end of the wireless power transmission system of the present invention to realize the voltage stabilizing power transmission control of the temperature sensor. A WiFi module is used to transmit information between the receiving end MCU controller and the transmitting end MCU controller, and an impedance matching circuit and related algorithms are added to the receiving end to further improve the power transmission efficiency and stability of the temperature sensor. The stability, convenience, measurement accuracy and reliability of the overall power transmission of the temperature sensor in the liquid couple device are improved.

[0046] The present invention is mainly applied to temperature sensors in ship liquid coupling devices. The temperature sensor is supplied with electric energy in a contactless manner. Compared with the wired transmission method, the wireless power transmission device has better safety and mobility.

[0047] The present invention does not require wiring and is easy to install: there is no need to connect cables between the inside and outside of the liquid coupling device, the installation is convenient and quick, and the installation and maintenance costs can be greatly reduced.

[0048] The present invention has strong anti-interference capability: it adopts electromagnetic induction to transmit energy, is not affected by electromagnetic interference of cables, and adds impedance matching algorithm in the receiving end circuit, so it has strong anti-interference capability.

[0049] The invention has high reliability: the wireless power transmission device of the invention has high reliability in the temperature sensor of the coupling device, and due to the addition of the impedance matching circuit, its transmission efficiency and stability are further enhanced.

[0050] The present invention has strong adaptability: the present invention can be applied to various complex working environments and transmit electric energy in a contactless manner. BRIEF DESCRIPTION OF THE DRAWINGS

[0051] Figure 1 A topological schematic diagram of a system for wirelessly powering a temperature sensor in a liquid coupling device;

[0052] Figure 2 A closed-loop control schematic diagram of a system for wirelessly powering a temperature sensor in a liquid coupling device;

[0053] Figure 3 is a circuit diagram of a DC-DC conversion circuit;

[0054] Figure 4 is a circuit diagram of a full-bridge inverter circuit;

[0055] Figure 5 is a circuit diagram of a full-bridge active rectifier circuit;

[0056] Figure 6 This is a simulation diagram of the coupled coil. DETAILED DESCRIPTION

[0057] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0058] It should be noted that, in the absence of conflict, the embodiments of the present invention and the features in the embodiments may be combined with each other.

[0059] The present invention will be further described below in conjunction with the accompanying drawings and specific embodiments, but they are not intended to limit the present invention.

[0060] Example:

[0061] Combination Figure 1 and Figure 2 , describing this embodiment, a system for wirelessly powering a temperature sensor in a liquid coupling device, the system comprising a power sending module, a power receiving module and a control module;

[0062] The power transmission module is arranged outside the liquid coupling device, and the power receiving module is arranged inside the liquid coupling device; the power transmission module wirelessly supplies power to the power receiving module, and the power receiving module receives power to supply power to the powered temperature sensor 5;

[0063] The power transmission module includes a DC power supply, a DC-DC conversion circuit 1, a full-bridge inverter circuit 2 and a transmitting coil 3-1;

[0064] The power receiving module includes a receiving coil 3-2 and a full-bridge active rectification impedance matching circuit 4;

[0065] A control module, used to generate a corresponding PWM drive signal according to the actual supply voltage value of the powered temperature sensor 5; and also used to obtain a PWM signal with an optimal duty cycle according to the voltage value and current value output by the full-bridge inverter circuit 2 and the AC power coupled by the receiving coil 3-2;

[0066] The DC-DC conversion circuit 1 is used to instruct the received DC power to perform voltage conversion according to the received PWM drive signal, and the converted DC power is transmitted to the full-bridge inverter circuit 2; the full-bridge inverter circuit 2 is used to instruct the received DC power to be converted into high-frequency AC power according to the PWM signal of the preset frequency generated by the receiving control module, and transmit it to the transmitting coil 3-1;

[0067] The transmitting coil 3-1 is used to convert the received high-frequency alternating current into electromagnetic field energy and transmit it to the receiving coil 3-2;

[0068] The receiving coil 3-2 is used to convert the received electromagnetic field energy into AC electric energy and transmit it to the full-bridge active rectification impedance matching circuit 4;

[0069] The full-bridge active rectification impedance matching circuit 4 is used to guide the received AC power to be converted into DC power to power the temperature sensor 5 according to the received PWM signal with the optimal duty cycle.

[0070] Specifically, by Figure 2It can be seen that the DC power supply transfers electrical energy to Figure 3 The DC-DC conversion circuit shown in the figure is designed as a BUCK type step-down circuit. The MCU controller at the transmitting end compares the expected voltage with the actual output voltage at the receiving end through the PI controller, controls the duty cycle of the PWM signal transmitted to the DC-DC conversion circuit, and thus controls the stable voltage supplied to the temperature sensor. The MCU uses the STM32F103VET6 chip as the main control chip of the system. The maximum clock frequency allowed by this chip is 72MHZ. In order to increase the operation speed as much as possible, an external clock of 8MHZ is designed, and the PLLXTPRE switch controller is set to non-divided frequency mode.

[0071] The MCU controller at the transmitting end controls the output of two high-frequency AC PWM signals to be transmitted to the Figure 4 The full-bridge inverter circuit shown in the figure emits high-frequency alternating current to establish a transmission magnetic field, wherein the switching device in the high-frequency inverter circuit uses a DMT3009LDT-7 MOSFET tube as a switching device, and the device packages two MOSFET tubes together, which saves space. The RMS calculated value of the output voltage and current of the inverter circuit is then transmitted to the receiving end MCU controller through the WIFI module, and the WIFI module uses the ESP8266 module. After the receiving end receives the high-frequency alternating current converted from the alternating magnetic field, the receiving end MCU controller samples the receiving coil current synchronization signal, and uses the optimal duty cycle calculation model combined with the received transmitter parameters to derive the optimal duty cycle for emitting a PWM signal, and sends the synchronized PWM signal to the receiving end. Figure 5 In the full-bridge active rectification impedance matching circuit shown in the figure, the switch device in the full-bridge active rectification impedance matching circuit adopts CMP060N10 NMOS switch tube to achieve the rectification and impedance matching goals. The collected actual load voltage value is sent to the MCU controller at the transmitting end through the WIFI module to complete the closed-loop voltage regulation task. Thus, the system as a whole realizes real-time optimal efficiency transmission and maintains stable output power. Figure 6 The simulation diagram of the coupling coil design is used to realize the power transfer between the transmitter and the receiver. The overall goal is to provide power to the temperature sensor in the liquid couple device.

[0072] The following describes the composition of the control module:

[0073] The control module includes a sending end MCU controller 6, a receiving end MCU controller 7 and a WIFI module 8;

[0074] The sending end MCU controller 6 is arranged outside the liquid coupling device, and the receiving end MCU controller 7 is arranged inside the liquid coupling device;

[0075] The receiving end MCU controller 7 is used to collect the actual supply voltage value of the powered temperature sensor 5 and send it to the sending end MCU controller 6 through the WIFI module 8; it is also used to collect the AC power coupled by the receiving coil 3-2, and combine the received RMS value to obtain the PWM signal with the optimal duty cycle, and send it to the full-bridge active rectification impedance matching circuit 4;

[0076] The sending end MCU controller 6 is used to compare the expected voltage value with the actual power supply voltage value of the powered temperature sensor 5, generate a corresponding PWM drive signal, and send it to the DC-DC conversion circuit 1; it is also used to output a PWM signal of a preset frequency to the full-bridge inverter circuit 2; it is also used to collect the voltage value and current value output by the full-bridge inverter circuit 2, calculate the root mean square value, and send it to the receiving end MCU controller 7 through the WIFI module 8.

[0077] The optimal duty cycle is further defined below and is expressed as:

[0078]

[0079] Where D η-max is the optimal duty cycle value after model calculation, M is the mutual inductance value, R is the internal resistance of the two-terminal coil, R1 is the real-time actual impedance value of the receiving end, and ω is the system operating angular frequency;

[0080] Among them, the mutual inductance value M is expressed as:

[0081]

[0082] Where D is the duty cycle value set for the receiving end output, U in is the output voltage of the transmitter, I in is the output current value of the transmitter.

[0083] Specifically, according to the experimental results, the initial value of D is set to 0.45.

[0084] The composition of the DC-DC conversion circuit 1 is defined as follows: the DC-DC conversion circuit 1 includes a half-bridge driver chip U1 of model IR2109, resistors R1-R8, IGBT switches S1-S2, an inductor L1, electrolytic capacitors C1-C7 and a diode D1;

[0085] The positive pole of the power supply is connected to pin 1 and pin 3 of the IR2109 half-bridge driver chip U1 and the anode of the diode D1 at the same time, the pin 2 of the IR2109 half-bridge driver chip U1 is connected to the PWM drive signal output end of the sending end MCU controller 6, and the negative pole of the power supply is connected to pin 4 of the IR2109 half-bridge driver chip;

[0086] The cathode of the diode D1 is connected to the No. 8 pin of the IR2109 half-bridge driver chip U1 and the positive electrode of the capacitor C1 at the same time, the negative electrode of the capacitor C1 is connected to the No. 6 pin of the IR2109 half-bridge driver chip U1, the No. 7 pin of the IR2109 half-bridge driver chip U1 is connected to one end of the resistor R1, the other end of the resistor R1 is connected to the gate of the IGBT switch tube S1, the source of the IGBT switch tube S1 is connected to the positive electrode of the electrolytic capacitor C2, the positive electrode of the electrolytic capacitor C3, the positive electrode of the electrolytic capacitor C4 and the positive electrode of the DC power supply at the same time, and the negative electrode of the electrolytic capacitor C2, the negative electrode of the electrolytic capacitor C3, the negative electrode of the electrolytic capacitor C4 and the negative electrode of the DC power supply are all connected to the power ground;

[0087] The drain of the IGBT switch tube S1 is simultaneously connected to one end of the inductor L1, the source of the IGBT switch tube S2, the negative electrode of the capacitor C1 and the pin 6 of the IR2109 half-bridge driver chip U1. The other end of the inductor L1 is simultaneously connected to the positive electrode of the electrolytic capacitor C5, the positive electrode of the electrolytic capacitor C6, the positive electrode of the electrolytic capacitor C7, one end of the resistor R3 and the positive output end of the DC-DC conversion circuit 1. The negative output end of the DC power of the DC-DC conversion circuit 1 is simultaneously connected to the power supply and the resistor One end of R6, the other end of resistor R6, one end of resistor R5, the negative electrode of electrolytic capacitor C7, the negative electrode of electrolytic capacitor C6, the negative electrode of electrolytic capacitor C5 and the drain of IGBT switch tube S2 are all connected to the power ground, the gate of IGBT switch tube S2 is connected to one end of resistor R2, the other end of resistor R2 is connected to pin 5 of IR2109 half-bridge driver chip U1, the other end of resistor R5 is connected to one end of resistor R4, and the other end of resistor R4 is simultaneously connected to the other end of resistor R3 and the power supply.

[0088] The composition of the full-bridge inverter circuit is introduced below: The full-bridge inverter circuit 2 includes resistors R9-R21, capacitors C10-C19 and IGBT switches G1-G4;

[0089] The first PWM signal output end of the MCU controller at the transmitting end is connected to one end of the resistor R10, and the other end of the resistor R10 is simultaneously connected to one end of the resistor R9 and the gate of the IGBT switch tube G1, the source of the IGBT switch tube G1 is simultaneously connected to one end of the capacitor C10, one end of the capacitor C12, one end of the capacitor C13, one end of the capacitor C20, the drain of the IGBT switch tube G3 and the output end of the DC-DC conversion circuit 1, the drain of the IGBT switch tube G1 is simultaneously connected to the source of the IGBT switch tube G2, one end of the resistor R12, the other end of the resistor R9, one end of the capacitor C11, one end of the capacitor C14, one end of the capacitor C15, one end of the capacitor C16 and one end of the capacitor C17, the other end of the capacitor C14, the other end of the capacitor C15, the other end of the capacitor C16 and the other end of the capacitor C17 are all connected to one AC output end of the transmitting coil; the other end of the resistor R12 is connected to the other end of the capacitor C10;

[0090] The second PWM signal output end of the MCU controller 6 at the sending end is connected to one end of the resistor R11, the other end of the resistor R11 is simultaneously connected to the gate of the IGBT switch tube G2 and one end of the resistor R13, the other end of the resistor R13 is simultaneously connected to one end of the resistor R14, one end of the resistor R21, the drain of the IGBT switch tube G2, one end of the resistor R16, one end of the resistor R18 and the source of the IGBT switch tube G4, and the other end of the resistor R21 is connected to the power ground;

[0091] The other end of the resistor R16 is connected to one end of the capacitor C19, and the other end of the capacitor C19 is simultaneously connected to one end of the resistor R15, the source of the IGBT switch tube G3, the drain of the IGBT switch tube G2, one end of the resistor R17 and the other AC output end of the transmitting coil, the other end of the resistor R15 is connected to the other end of the capacitor C20, the other end of the resistor R17 is simultaneously connected to the gate of the IGBT switch tube G3 and one end of the resistor R19, the other end of the resistor R19 is connected to the third PWM signal output end of the sending end MCU controller 6, the other end of the resistor R18 is simultaneously connected to the gate of the IGBT switch tube G4 and one end of the resistor 20, and the other end of the resistor 20 is connected to the fourth PWM signal output end of the sending end MCU controller 6.

[0092] The composition of the full-bridge active rectifier circuit is introduced below: The full-bridge active rectifier circuit 4 includes capacitors C21-C24, resistors R22-R29 and IGBT switches Q1-Q4;

[0093] One AC output end of the receiving coil 3 - 2 is simultaneously connected to one end of the capacitor C21 , one end of the capacitor C22 , and one end of the capacitor C23 ;

[0094] The other end of capacitor C21, the other end of capacitor C22 and the other end of capacitor C23 are all connected to the positive measuring end of the capacitor;

[0095] The other AC output end of the receiving coil 3 - 2 is connected to the source of the IGBT switch tube Q4 and the source of the IGBT switch tube Q3 at the same time;

[0096] The first optimal duty cycle PWM signal output end of the receiving end MCU controller 7 is simultaneously connected to one end of the resistor R22 and the gate of the IGBT switch tube Q1, and the drain of the IGBT switch tube Q1 is simultaneously connected to the other end of the resistor R22, the negative electrode measurement end of the capacitor and the source of the IGBT switch tube Q3;

[0097] The third optimal duty cycle PWM signal output end of the receiving end MCU controller 7 is simultaneously connected to one end of the resistor R24 ​​and the gate of the IGBT switch tube Q3, and the drain of the IGBT switch tube Q3 is simultaneously connected to the other end of the resistor R24, one end of the resistor R25, the drain of the IGBT switch tube Q4, the negative electrode of the electrolytic capacitor C24, one end of the resistor R28, one end of the resistor R29, the power ground and the power ground measurement point;

[0098] The second optimal duty cycle PWM signal output end of the receiving end MCU controller 7 is simultaneously connected to one end of the resistor R23 and the gate of the IGBT switch tube Q2, the source of the IGBT switch tube Q2 is simultaneously connected to the source of the IGBT switch tube Q1, the positive electrode of the electrolytic capacitor C24, one end of the resistor R26 and the positive electrode measurement end of the actual power supply voltage value of the powered temperature sensor 5, the negative electrode measurement end of the actual power supply voltage value of the powered temperature sensor 5 is simultaneously connected to the current measurement end and the other end of the resistor R29; the other end of the resistor R26 is simultaneously connected to one end of the resistor R27 and the input end of the temperature sensor 5, and the other end of the resistor R27 is connected to the other end of the resistor R28.

[0099] The following introduces the main control chip models used by the sending end MCU controller 6 and the receiving end MCU controller 7: the sending end MCU controller 6 and the receiving end MCU controller 7 are both implemented using a chip model of STM32F103VET6.

[0100] The following introduces the models of WIFI modules: WIFI module 8 is implemented using the ESP8266 chip.

[0101] Although the present invention is described herein with reference to specific embodiments, it should be understood that these embodiments are merely examples of the principles and applications of the present invention. It should therefore be understood that many modifications may be made to the exemplary embodiments and that other arrangements may be devised without departing from the spirit and scope of the present invention as defined by the appended claims. It should be understood that the various dependent claims and features described herein may be combined in a manner different from that described in the original claims. It should also be understood that features described in conjunction with individual embodiments may be used in other described embodiments.

Claims

1. A system for wirelessly powering a temperature sensor in a liquid coupling device, characterized in that: The system includes a power sending module, a power receiving module and a control module; The power transmission module is arranged outside the liquid coupling device, and the power receiving module is arranged inside the liquid coupling device; the power transmission module wirelessly supplies power to the power receiving module, and the power receiving module receives power to supply power to the powered temperature sensor (5); The electric energy transmission module comprises a direct current power supply, a DC-DC conversion circuit (1), a full-bridge inverter circuit (2) and a transmitting coil (3-1); The electric energy receiving module comprises a receiving coil (3-2) and a full-bridge active rectification impedance matching circuit (4); A control module, used for generating a corresponding PWM drive signal according to an actual supply voltage value of the powered temperature sensor (5); It is also used to obtain a PWM signal with an optimal duty cycle according to the voltage value and current value output by the full-bridge inverter circuit (2) and the alternating current coupled by the receiving coil (3-2); A DC-DC conversion circuit (1) is used to instruct the received DC power to undergo voltage conversion according to the received PWM drive signal, and transmit the converted DC power to the full-bridge inverter circuit (2); The full-bridge inverter circuit (2) directs the received direct current to be converted into high-frequency alternating current according to the PWM signal of a preset frequency generated by the receiving control module, and transmits it to the transmitting coil (3-1); The transmitting coil (3-1) is used to convert the received high-frequency alternating current into electromagnetic field energy and transmit it to the receiving coil (3-2); A receiving coil (3-2) is used to convert the received electromagnetic field energy into AC electric energy and transmit it to the full-bridge active rectification impedance matching circuit (4); The full-bridge active rectification impedance matching circuit (4) is used to guide the received AC power to be converted into DC power to supply power to the temperature sensor (5) according to the received PWM signal with the optimal duty cycle.

2. A system for wirelessly powering a temperature sensor in a liquid coupling device according to claim 1, characterized in that: The control module comprises a sending end MCU controller (6), a receiving end MCU controller (7) and a WIFI module (8); The sending end MCU controller (6) is arranged outside the liquid coupling device, and the receiving end MCU controller (7) is arranged inside the liquid coupling device; The receiving end MCU controller (7) is used to collect the actual power supply voltage value of the powered temperature sensor (5) and send it to the sending end MCU controller (6) through the WIFI module (8); it is also used to collect the alternating current coupled by the receiving coil (3-2), combine the received root mean square value, obtain a PWM signal with an optimal duty cycle, and send it to the full-bridge active rectification impedance matching circuit (4); The sending end MCU controller (6) is used to compare the expected voltage value with the actual supply voltage value of the powered temperature sensor (5), generate a corresponding PWM drive signal, and send it to the DC-DC conversion circuit (1); it is also used to output a PWM signal of a preset frequency to the full-bridge inverter circuit (2); it is also used to collect the voltage value and current value output by the full-bridge inverter circuit (2), calculate the root mean square value, and send it to the receiving end MCU controller (7) through the WIFI module (8).

3. A system for wirelessly powering a temperature sensor in a liquid coupling device according to claim 1, characterized in that: The optimal duty cycle is expressed as: Where D η-max is the optimal duty cycle value after model calculation, M is the mutual inductance value, R is the internal resistance of the two-terminal coil, R1 is the real-time actual impedance value of the receiving end, and ω is the system operating angular frequency; Among them, the mutual inductance value M is expressed as: Where D is the duty cycle value set for the receiving end output, U in is the output voltage of the transmitter, I in is the output current value of the transmitter.

4. A system for wirelessly powering a temperature sensor in a liquid coupling device according to claim 1, characterized in that: The DC-DC conversion circuit (1) includes a half-bridge driver chip U1 of model IR2109, resistors R1-R8, IGBT switches S1-S2, an inductor L1, electrolytic capacitors C1-C7 and a diode D1; The positive pole of the power supply is connected to pin 1, pin 3 and the anode of the diode D1 of the IR2109 half-bridge driver chip U1, pin 2 of the IR2109 half-bridge driver chip U1 is connected to the PWM drive signal output end of the sending end MCU controller (6), and the negative pole of the power supply is connected to pin 4 of the IR2109 half-bridge driver chip; The cathode of the diode D1 is connected to the No. 8 pin of the IR2109 half-bridge driver chip U1 and the positive electrode of the capacitor C1 at the same time, the negative electrode of the capacitor C1 is connected to the No. 6 pin of the IR2109 half-bridge driver chip U1, the No. 7 pin of the IR2109 half-bridge driver chip U1 is connected to one end of the resistor R1, the other end of the resistor R1 is connected to the gate of the IGBT switch tube S1, the source of the IGBT switch tube S1 is connected to the positive electrode of the electrolytic capacitor C2, the positive electrode of the electrolytic capacitor C3, the positive electrode of the electrolytic capacitor C4 and the positive electrode of the DC power supply at the same time, and the negative electrode of the electrolytic capacitor C2, the negative electrode of the electrolytic capacitor C3, the negative electrode of the electrolytic capacitor C4 and the negative electrode of the DC power supply are all connected to the power ground; The drain of the IGBT switch tube S1 is simultaneously connected to one end of the inductor L1, the source of the IGBT switch tube S2, the negative electrode of the capacitor C1 and the pin 6 of the IR2109 half-bridge driver chip U1. The other end of the inductor L1 is simultaneously connected to the positive electrode of the electrolytic capacitor C5, the positive electrode of the electrolytic capacitor C6, the positive electrode of the electrolytic capacitor C7, one end of the resistor R3 and the positive output end of the direct current of the DC-DC conversion circuit (1). The negative output end of the direct current of the DC-DC conversion circuit (1) is simultaneously connected to the power supply and One end of resistor R6, the other end of resistor R6, one end of resistor R5, the negative electrode of electrolytic capacitor C7, the negative electrode of electrolytic capacitor C6, the negative electrode of electrolytic capacitor C5 and the drain of IGBT switch tube S2 are all connected to the power ground, the gate of IGBT switch tube S2 is connected to one end of resistor R2, the other end of resistor R2 is connected to pin 5 of IR2109 half-bridge driver chip U1, the other end of resistor R5 is connected to one end of resistor R4, and the other end of resistor R4 is simultaneously connected to the other end of resistor R3 and the power supply.

5. A system for wirelessly powering a temperature sensor in a liquid coupling device according to claim 1, characterized in that: The full-bridge inverter circuit (2) includes resistors R9-R21, capacitors C10-C19 and IGBT switches G1-G4; The first PWM signal output end of the MCU controller at the transmitting end is connected to one end of the resistor R10, the other end of the resistor R10 is simultaneously connected to one end of the resistor R9 and the gate of the IGBT switch tube G1, the source of the IGBT switch tube G1 is simultaneously connected to one end of the capacitor C10, one end of the capacitor C12, one end of the capacitor C13, one end of the capacitor C20, the drain of the IGBT switch tube G3 and the output end of the DC-DC conversion circuit (1), the drain of the IGBT switch tube G1 is simultaneously connected to the source of the IGBT switch tube G2, one end of the resistor R12, the other end of the resistor R9, one end of the capacitor C11, one end of the capacitor C14, one end of the capacitor C15, one end of the capacitor C16 and one end of the capacitor C17, the other end of the capacitor C14, the other end of the capacitor C15, the other end of the capacitor C16 and the other end of the capacitor C17 are all connected to one AC output end of the transmitting coil (3-1); the other end of the resistor R12 is connected to the other end of the capacitor C10; The second PWM signal output end of the sending end MCU controller (6) is connected to one end of a resistor R11, the other end of the resistor R11 is simultaneously connected to the gate of the IGBT switch tube G2 and one end of a resistor R13, the other end of the resistor R13 is simultaneously connected to one end of a resistor R14, one end of a resistor R21, the drain of the IGBT switch tube G2, one end of a resistor R16, one end of a resistor R18 and the source of the IGBT switch tube G4, and the other end of the resistor R21 is connected to a power ground; The other end of the resistor R16 is connected to one end of the capacitor C19, and the other end of the capacitor C19 is simultaneously connected to one end of the resistor R15, the source of the IGBT switch tube G3, the drain of the IGBT switch tube G2, one end of the resistor R17 and another AC output end of the transmitting coil (3-1). The other end of the resistor R15 is connected to the other end of the capacitor C20, and the other end of the resistor R17 is simultaneously connected to the gate of the IGBT switch tube G3 and one end of the resistor R19. The other end of the resistor R19 is connected to the third PWM signal output end of the transmitting end MCU controller (6). The other end of the resistor R18 is simultaneously connected to the gate of the IGBT switch tube G4 and one end of the resistor 20. The other end of the resistor 20 is connected to the fourth PWM signal output end of the transmitting end MCU controller (6).

6. A system for wirelessly powering a temperature sensor in a liquid coupling device according to claim 1, characterized in that: The full-bridge active rectification impedance matching circuit (4) comprises capacitors C21-C24, resistors R22-R29 and IGBT switches Q1-Q4; One AC output end of the receiving coil (3-2) is simultaneously connected to one end of the capacitor C21, one end of the capacitor C22 and one end of the capacitor C23; The other end of capacitor C21, the other end of capacitor C22 and the other end of capacitor C23 are all connected to the positive measuring end of the capacitor; Another AC output end of the receiving coil (3-2) is connected to the source of the IGBT switch tube Q4 and the source of the IGBT switch tube Q3 at the same time; The first optimal duty cycle PWM signal output end of the receiving end MCU controller (7) is simultaneously connected to one end of the resistor R22 and the gate of the IGBT switch tube Q1, and the drain of the IGBT switch tube Q1 is simultaneously connected to the other end of the resistor R22, the negative electrode measurement end of the capacitor and the source of the IGBT switch tube Q3; The third optimal duty cycle PWM signal output end of the receiving end MCU controller (7) is simultaneously connected to one end of the resistor R24 ​​and the gate of the IGBT switch tube Q3, and the drain of the IGBT switch tube Q3 is simultaneously connected to the other end of the resistor R24, one end of the resistor R25, the drain of the IGBT switch tube Q4, the negative electrode of the electrolytic capacitor C24, one end of the resistor R28, one end of the resistor R29, the power ground and the power ground measurement point; The second optimal duty cycle PWM signal output end of the receiving end MCU controller (7) is simultaneously connected to one end of the resistor R23 and the gate of the IGBT switch tube Q2; the source of the IGBT switch tube Q2 is simultaneously connected to the source of the IGBT switch tube Q1, the positive electrode of the electrolytic capacitor C24, one end of the resistor R26 and the positive electrode measurement end of the actual power supply voltage value of the powered temperature sensor (5); the negative electrode measurement end of the actual power supply voltage value of the powered temperature sensor (5) is simultaneously connected to the current measurement end and the other end of the resistor R29; the other end of the resistor R26 is simultaneously connected to one end of the resistor R27 and the input end of the temperature sensor (5); the other end of the resistor R27 is connected to the other end of the resistor R28.

7. A system for wirelessly powering a temperature sensor in a liquid coupling device according to claim 1, characterized in that: The sending end MCU controller (6) and the receiving end MCU controller (7) are both implemented using a chip of model STM32F103VET6.

8. A system for wirelessly powering a temperature sensor in a liquid coupling device according to claim 1, characterized in that: The WIFI module (8) is implemented using the ESP8266 chip.

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