New energy automobile rotary transformer decoding excitation output short circuit protection circuit

Abstract

The invention discloses a resolver decoding excitation output short-circuit protection circuit for a new energy automobile. The resolver decoding excitation output short-circuit protection circuit comprises a current-limiting protection power supply circuit, a resolver decoding chip circuit and a large-current operational amplifier and output-input circuit, and the large-current operational amplifier and output / input circuit is connected with the current-limiting protection power supply circuit and the rotary transformer decoding chip circuit. The power supply chip capable of carrying out current-limiting hiccup protection is used for carrying out monitoring protection on the current of the rotary transformer decoding system, enough power can be provided, meanwhile, the rotary transformer decoding system can be effectively protected, and damage caused by severe working conditions is prevented.

Description

Technical Field

[0001] The present invention belongs to the technical field of short - circuit protection circuits, and relates to a resolver decoding excitation output short - circuit protection circuit for new energy vehicles. Background Art

[0002] In new energy vehicles, the resolver is currently the mainstream sensor for measuring the angular displacement and angular velocity of the motor of new energy vehicles. It requires a sine - wave excitation of 10 kHz or 5 kHz to work. Since the excitation signal output by a general resolver decoding chip is too small, the signal output by the resolver is prone to interference. Therefore, an operational amplifier is needed to amplify this excitation signal to enhance its anti - interference ability. And the higher the excitation signal is amplified to a certain extent, the higher the output ability of the operational amplifier required. However, if the excitation is short - circuited, the short - circuit current will be larger, which often causes the output resistance of the excitation or the operational amplifier to burn out due to the large current.

[0003] Currently, the excitation output of most resolver decoding systems is an ordinary operational amplifier followed by a push - pull circuit to ensure the power of the excitation output. Many resolver decoding systems do not have excitation output protection. Either they stack output resistors and rely on the quantity to resist the large current, or they are directly damaged by short - circuit. Therefore, an excitation output short - circuit protection circuit is needed to protect the excitation output from being damaged under conditions such as resolver damage or short - circuit. Summary of the Invention

[0004] To solve the problems in the background art, the present invention proposes a resolver decoding excitation output short - circuit protection circuit for new energy vehicles.

[0005] To achieve the above object, the technical solution adopted by the present invention is as follows: A resolver decoding excitation output short - circuit protection circuit for new energy vehicles, comprising: a current - limiting protection power supply circuit, a resolver decoding chip circuit, a high - current operational amplifier and an input - output circuit; The high - current operational amplifier and the input - output circuit are connected to the current - limiting protection power supply circuit and the resolver decoding chip circuit.

[0006] The current - limiting protection power supply circuit includes: resistor R1, resistor R2, resistor R3, resistor R4, resistor R5, resistor R6, resistor R7, resistor R8, capacitor C1, capacitor C2, capacitor C3, capacitor C4, capacitor C5, capacitor C6, capacitor C7, capacitor C8, capacitor C9, diode D1, diode D2, diode D3, inductor L1, power supply chip U1; One end of the capacitor C1 is connected to the input power supply +12V, the first pin VIN of the power supply chip U1, the ninth pin VIN of the power supply chip U1, and one end of the resistor R1. The other end of the capacitor C1 is connected to the pin GND of the power supply chip U1 and the ground. The capacitors C2, C3, and C4 are connected in parallel across the two ends of the capacitor C1. The other end of the resistor R1 is connected to the pin EN of the power supply chip U1; The pin IS of the power supply chip U1 is connected to one end of the resistor R3. The other end of the resistor R3 is connected to the pin VS of the power supply chip U1, one end of the inductor L1, one end of the capacitor C5, and the negative electrode of the diode D2. The resistor R2 is connected in parallel across the two ends of the resistor R3. The other end of the capacitor C5 is connected to the pin VB of the power supply chip U1 and the positive electrode of the diode D1. The negative electrode of the diode D1 is connected to the negative electrode of the diode D3. The positive electrode of the diode D3 is connected to one end of the resistor R4. The other end of the resistor R4 is connected to the other end of the inductor L1, one end of the resistor R5, and one end of the capacitor C6. The other end of the resistor R5 is connected to one end of the resistor R7, one end of the resistor R6, the other end of the capacitor C6, and the pin FB of the power supply chip U1. The other end of the resistor R7 is connected to the other end of the resistor R6, the positive electrode of the diode D2, and the ground. One end of the capacitor C7 is connected to one end of the resistor R5 and the output power supply +11V. The other end of the capacitor C7 is connected to the ground. The capacitors C8, C9, and the resistor R8 are connected in parallel across the two ends of the capacitor C7; The power supply chip U1 has a current limiting function and can monitor the flowing current. Moreover, the restart time of the hiccup mode of the current limiting protection of this power supply chip is at the second level, which can reduce its own heat generation during a short circuit.

[0007] The resolver decoding chip circuit includes: a main control circuit and an interface circuit; The main control circuit is connected to the interface circuit.

[0008] The main control chip includes: the ADI chip U2, the resistor R9, the resistor R10, the resistor R11, the capacitor C10, the capacitor C11, the capacitor C12, the capacitor C13, the capacitor C14, the fuse X1, the light-emitting diode LED1, and the light-emitting diode LED2; The input power supply +5V is connected to the first pin DVDD of the ADI chip U2 and the pin RDVEL# of the ADI chip U2. The pin SOE# of the DI chip U2 is connected to the ground. One end of the resistor R9 is connected to the pin XTALOUT of the ADI chip U2 and one end of the capacitor C10. The other end of the resistor R9 is connected to the pin CLKIN of the ADI chip U2 and one end of the capacitor C11. The fuse X1 is connected in parallel across the two sides of the resistor R9. The other end of the capacitor C10 is connected to the other end of the capacitor C11 and the ground; The REFOUT pin of the ADI chip U2 is connected to one end of the capacitor C12. The other end of the capacitor C12 is connected to one end of the capacitor C14, the forty-second pin AGND of the ADI chip U2, and the ground. The other end of the capacitor C14 is connected to the REFBYP pin of the ADI chip U2. The capacitor C13 is connected in parallel across the two ends of the capacitor C14. The AVDD pin of the ADI chip U2 is connected to the ground. The thirty-sixth pin AGND of the ADI chip U2 is connected to the ground. The LOT pin of the ADI chip U2 is connected to one end of the resistor R11. The other end of the resistor R11 is connected to the cathode of the light-emitting diode LED2. The DOS pin of the ADI chip U2 is connected to one end of the resistor R10. The other end of the resistor R10 is connected to the cathode of the light-emitting diode LED1. The anode of the light-emitting diode LED2 is connected to the anode of the light-emitting diode LED1 and the input power supply +5V. The DGND pin of the ADI chip U2 is connected to the ground.

[0009] The interface circuit includes: resistors R12, R13, R14, R15, R16, R17, R18; The input power supply +5V is connected to one end of the resistors R12, R13, R14, R15, R16, R17, R18. The other end of the resistor R12 is connected to the SAMPLE# pin of the ADI chip U2, the other end of the resistor R13 is connected to the DB10 / SCLK pin of the ADI chip U2, the other end of the resistor R14 is connected to the DIR pin of the ADI chip U2, the other end of the resistor R15 is connected to the A pin of the ADI chip U2, the other end of the resistor R16 is connected to the B pin of the ADI chip U2, the other end of the resistor R17 is connected to the RESET# pin of the ADI chip U2, and the other end of the resistor R18 is connected to the RD pin of the ADI chip U2.

[0010] The high-current operational amplifier and input / output circuit includes: a power supply circuit, an operational amplifier processing circuit, an isolation circuit, and a signal conditioning output circuit; The power supply circuit is connected to the main control circuit and the operational amplifier processing circuit. The main control circuit is connected to the operational amplifier processing circuit and the signal conditioning circuit. The operational amplifier processing circuit is connected to the isolation circuit.

[0011] The power supply circuit includes capacitors C20, C21, C22, C23, resistors R29, R30, R31; One end of the capacitor C20 is connected to the input power supply +11V. The other end of the capacitor C20 is connected to the ground. The capacitors C21 and C22 are connected in parallel across the two ends of the capacitor C20; One end of resistor R29 is connected to the input power supply +5V, the other end of resistor R29 is connected to one end of capacitor C23, the other end of capacitor C23 is connected to ground, and resistors R30 and R31 are connected in parallel across capacitor C23.

[0012] The operational amplifier processing circuit includes: resistors R19, R20, R21, R22, R22, 23, 24, 25, 26, 27, 28, capacitors C15, C16, and operational amplifier U3; Pin EXC of ADI chip U2 is connected to one end of resistor R19, the other end of resistor R19 is connected to one end of resistor R20, the other end of resistor R20 is connected to one end of resistor R21 and pin InputsA- of operational amplifier U3, the other end of resistor R21 is connected to one end of resistor R22, the other end of resistor R22 is connected to pin OutputA of operational amplifier U3, capacitor C15 is connected in parallel across resistor R21, resistor R23 is connected in parallel across resistor R22, pin NC of the eleventh pin of operational amplifier U3, pin VEE - GND of the twelfth pin of operational amplifier U3, pin VEE - GND of the thirteenth pin of operational amplifier U3, pin NC of the fourteenth pin of operational amplifier U3, and pin NC of the fifteenth pin of operational amplifier U3 are connected to ground; Pin EXC# of ADI chip U2 is connected to one end of resistor R24, the other end of resistor R24 is connected to one end of resistor R25, the other end of resistor R25 is connected to one end of resistor R26 and pin InputsB- of operational amplifier U3, the other end of resistor R26 is connected to one end of resistor R27, the other end of resistor R27 is connected to pin OutputB of operational amplifier U3, capacitor C16 is connected in parallel across resistor R26, resistor R28 is connected in parallel across resistor R27, pin NC of the sixth pin of operational amplifier U3, pin VEE - GND of the fifth pin of operational amplifier U3, pin VEE - GND of the fourth pin of operational amplifier U3, pin NC of the third pin of operational amplifier U3 are connected to ground, and pin VCC of operational amplifier U3 is connected to the input power supply +11V.

[0013] The isolation circuit includes: transformer L2, capacitors C17, C18, C19, and diode D4; The first pin of transformer L2 is connected to one end of resistor R23, the second pin of transformer L2 is connected to one end of resistor R28, the third pin of transformer L2 is connected to one end of capacitor C17, one end of capacitor C19, and the second pin of diode D4, the fourth pin of transformer L2 is connected to the other end of capacitor C17, one end of capacitor C18, and the first pin of diode D4, and the other end of capacitor C18 is connected to the other end of capacitor C19, the third pin of diode D4, and ground.

[0014] The signal conditioning circuit includes: resistor 32, resistor 33, resistor R34, resistor 35, resistor R36, capacitor C24, capacitor C25, capacitor C26, capacitor C27, capacitor C28, capacitor C29, transformer L3, diode D5, resistor 37, resistor 38, resistor R39, resistor 40, resistor R41, capacitor C30, capacitor C31, capacitor C32, capacitor C33, capacitor C34, capacitor C35, transformer L4, diode D6; The reference voltage 2.5VREF is connected to one end of resistor R33 and one end of resistor R34. The other end of resistor R33 is connected to one end of resistor R32, the SIN pin of ADI chip U2, one end of resistor R35, and one end of capacitor C25. The other end of resistor R35 is connected to one end of capacitor C27 and the first pin of transformer L3. The other end of capacitor C27 is connected to one end of resistor R36 and the second pin of transformer L3. The other end of resistor R36 is connected to the other end of resistor R34, one end of capacitor C26, the other end of resistor R32, and the SINLO pin of ADI chip U2. Capacitor C24 is connected in parallel across resistor R32. The other end of capacitor C25 is connected to the other end of capacitor C26 and ground. The third pin of transformer L3 is connected to one end of capacitor C29 and the first pin of diode D5. The fourth pin of transformer L3 is connected to one end of capacitor C28 and the second pin of diode D5. The other end of capacitor C28 is connected to the other end of capacitor C29, the third pin of diode D5, and ground; The reference voltage 2.5VREF is connected to one end of resistor R38 and one end of resistor R39. The other end of resistor R38 is connected to one end of resistor R37, the COS pin of ADI chip U2, one end of resistor R40, and one end of capacitor C31. The other end of resistor R40 is connected to one end of capacitor C33 and the first pin of transformer L4. The other end of capacitor C33 is connected to one end of resistor R41 and the second pin of transformer L4. The other end of resistor R41 is connected to the other end of resistor R39, one end of capacitor C32, the other end of resistor R37, and the COSLO pin of ADI chip U2. Capacitor C30 is connected in parallel across resistor R37. The other end of capacitor C31 is connected to the other end of capacitor C32 and ground. The third pin of transformer L4 is connected to one end of capacitor C35 and the first pin of diode D6. The fourth pin of transformer L4 is connected to one end of capacitor C34 and the second pin of diode D6. The other end of capacitor C34 is connected to the other end of capacitor C35, the third pin of diode D6, and ground.

[0015] Furthermore, Compared with the prior art, the present invention has the following beneficial effects: A solution using a high-power operational amplifier is adopted to replace the traditional solution of adding a push-pull circuit after the operational amplifier, reducing costs and PCB space. A power supply chip with a current limiting protection function or a current limiting protection chip is added before or after a power supply chip without a current limiting protection function to detect the current of the resolver decoding system and take protection actions to prevent the resolver decoding chip from being damaged due to abnormal operating conditions and overheating. When the voltage can be adjusted, the current can also be adjusted. When a certain current is reached, current limiting protection is performed to protect the resolver decoding system. Of course, a current limiting protection chip can also be added before or after a power supply chip without a current limiting protection function, and the current limiting protection chip is used to detect the current entering the resolver decoding system. If an abnormal current appears, the power supply chip is restricted from switching, so as to achieve the protection effect. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 is the block diagram of the resolver decoding excitation short-circuit protection circuit of the new energy vehicle of the present invention; Figure 2 is the circuit block diagram of the resolver decoding excitation short-circuit protection circuit of the new energy vehicle of the present invention; Figure 3 is the connection diagram of the power supply circuit with current limiting protection of the present invention; Figure 4 is the connection diagram of the resolver decoding chip circuit of the present invention; Figure 5 is the connection diagram of the high-current operational amplifier and the output-input circuit of the present invention. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0017] The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0018] As Figures 1 - 5 shown, the technical solution adopted by the present invention is as follows: A resolver decoding excitation output short-circuit protection circuit for a new energy vehicle includes: a power supply circuit with current limiting protection, a resolver decoding chip circuit, and a high-current operational amplifier and output-input circuit.

[0019] The high-current operational amplifier and output-input circuit are connected to the power supply circuit with current limiting protection and the resolver decoding chip circuit.

[0020] The current-limiting protection power supply circuit includes: resistor R1, resistor R2, resistor R3, resistor R4, resistor R5, resistor R6, resistor R7, resistor R8, capacitor C1, capacitor C2, capacitor C3, capacitor C4, capacitor C5, capacitor C6, capacitor C7, capacitor C8, capacitor C9, diode D1, diode D2, diode D3, inductor L1, and power supply chip U1.

[0021] One end of capacitor C1 is connected to the input power supply +12V, the first pin VIN of power supply chip U1, the ninth pin VIN of power supply chip U1, and one end of resistor R1. The other end of capacitor C1 is connected to the pin GND of power supply chip U1 and the ground. Capacitors C2, C3, and C4 are connected in parallel across both ends of capacitor C1. The other end of resistor R1 is connected to the pin EN of power supply chip U1.

[0022] The pin IS of power supply chip U1 is connected to one end of resistor R3. The other end of resistor R3 is connected to the pin VS of power supply chip U1, one end of inductor L1, one end of capacitor C5, and the cathode of diode D2. Resistor R2 is connected in parallel across resistor R3. The other end of capacitor C5 is connected to the pin VB of power supply chip U1 and the anode of diode D1. The cathode of diode D1 is connected to the cathode of diode D3. The anode of diode D3 is connected to one end of resistor R4. The other end of resistor R4 is connected to the other end of inductor L1, one end of resistor R5, and one end of capacitor C6. The other end of resistor R5 is connected to one end of resistor R7, one end of resistor R6, the other end of capacitor C6, and the pin FB of power supply chip U1. The other end of resistor R7 is connected to the other end of resistor R6, the anode of diode D2, and the ground. One end of capacitor C7 is connected to one end of resistor R5 and the output power supply +11V. The other end of capacitor C7 is connected to the ground. Capacitors C8, C9, and resistor R8 are connected in parallel across capacitor C7.

[0023] The power supply chip U1 is EG1192H, which has a current-limiting function, can monitor the current flowing through it, perform current-limiting protection, and its current-limiting protection hiccup mode restart time is at the second level, and it can reduce its own heat generation during short circuits. Resistors R2 and R3 are current-limiting sampling resistors, and current-limiting protection is performed by detecting the peak current flowing through the internal MOS transistor. It is also an adjustable power supply. By using the FB pin of power supply chip U1 and the external resistors R5, R6, and R7 for resistor voltage division, the output voltage can be adjusted. It can achieve both voltage adjustment and current adjustment.

[0024] Resistors R2 and R3 form a feedback voltage division circuit, sample the output voltage and feedback it to the feedback pin of power supply chip U1 to ensure that the output voltage is stable at the set value.

[0025] After the power input of +12V, it first passes through the filter circuit composed of capacitors C1, C2, and C3 to filter out high-frequency noise to stabilize the input voltage. Resistor R1 plays a role in current limiting or voltage division protection here to prevent the input pins of power chip U1 from being impacted by abnormal current. Power chip U1, as the core of DC-DC conversion, controls the periodic conduction or cut-off of diode D1: when diode D1 conducts, the power input of +12V charges inductor L1 through diode D1 to store energy; when diode D1 cuts off, inductor L1 releases energy to maintain the output current. Resistors R2 and R3 at the output end sample the output power of +11V voltage, and through diode D1 isolation, feedback to the feedback pin of power chip U1. Power chip U1 adjusts the duty cycle of diode D1 according to the feedback signal to ensure the stability of the output voltage. During the process, diodes D2 and D3 and resistor R4 assist in processing the feedback signal. Finally, inductor L1 and capacitors C4, C5, and C6 form a filter circuit to filter out voltage ripples, making the output power of +11V DC voltage smooth and stable to supply power to the rear-end load.

[0026] The resolver decoding chip circuit includes: a main control circuit and an interface circuit.

[0027] The main control circuit is connected to the interface circuit.

[0028] The main control chip includes: ADI chip U2, resistors R9, R10, R11, capacitors C10, C11, C12, C13, C14, fuse X1, light-emitting diodes LED1 and LED2.

[0029] The input power of +5V is connected to the first pin DVDD of ADI chip U2 and the pin RDVEL# of ADI chip U2. The pin SOE# of DI chip U2 is connected to the ground. One end of resistor R9 is connected to the pin XTALOUT of ADI chip U2 and one end of capacitor C10. The other end of resistor R9 is connected to the pin CLKIN of ADI chip U2 and one end of capacitor C11. Fuse X1 is connected in parallel on both sides of resistor R9. The other end of capacitor C10 is connected to the other end of capacitor C11 and the ground.

[0030] The REFOUT pin of the ADI chip U2 is connected to one end of the capacitor C12. The other end of the capacitor C12 is connected to one end of the capacitor C14, the forty-second pin AGND of the ADI chip U2, and ground. The other end of the capacitor C14 is connected to the REFBYP pin of the ADI chip U2. The capacitor C13 is connected in parallel across the two ends of the capacitor C14. The AVDD pin of the ADI chip U2 is connected to ground. The thirty-sixth pin AGND of the ADI chip U2 is connected to ground. The LOT pin of the ADI chip U2 is connected to one end of the resistor R11. The other end of the resistor R11 is connected to the cathode of the light-emitting diode LED2. The DOS pin of the ADI chip U2 is connected to one end of the resistor R10. The other end of the resistor R10 is connected to the cathode of the light-emitting diode LED1. The anode of the light-emitting diode LED2 is connected to the anode of the light-emitting diode LED1 and the input power supply +5V. The DGND pin of the ADI chip U2 is connected to ground.

[0031] The input power supply +5V supplies power to the ADI chip U2 through pins such as DVDD. The capacitors C10, C11 and the crystal oscillator form a clock circuit, and a stable clock is input through pins such as CLKIN to ensure the normal operation of the timing logic of the ADI chip U2. Data interaction depends on the data bus DB0 - DB10, and with control pins such as read and write, it coordinates the data read and write timing with external devices such as external memories. In terms of external signal processing, input pins such as the sampling trigger pin and the synchronous clock pin receive external sampling instructions and synchronous signals to drive the chip to process data; output pins such as the A_IC pin and the B_IC pin send control signals to external actuators. The light-emitting diodes LED1 and LED2 are current-limited by the resistors R10 and R11 to indicate the working state of the ADI chip U2 in real time.

[0032] The interface circuit includes: resistors R12, R13, R14, R15, R16, R17, R18.

[0033] The input power supply +5V is connected to one end of the resistors R12, R13, R14, R15, R16, R17, R18. The other end of the resistor R12 is connected to the SAMPLE# pin of the ADI chip U2. The other end of the resistor R13 is connected to the DB10 / SCLK pin of the ADI chip U2. The other end of the resistor R14 is connected to the DIR pin of the ADI chip U2. The other end of the resistor R15 is connected to the A pin of the ADI chip U2. The other end of the resistor R16 is connected to the B pin of the ADI chip U2. The other end of the resistor R17 is connected to the RESET# pin of the ADI chip U2. The other end of the resistor R18 is connected to the RD pin of the ADI chip U2.

[0034] Pins such as SAMPLE_IC, SCLK_IC, and DIR_IC are input interfaces responsible for receiving external signals. For example, the SAMPLE_IC pin receives the sampling trigger instruction from the external master device to start chip data acquisition; the SCLK_IC pin obtains the synchronous clock to ensure accurate data transmission timing; the DIR_IC pin can receive the direction control signal to set the data transmission direction. Pins such as A_IC, B_IC, and RST_IC are output interfaces that output the chip processing results. The RST_IC pin can send a reset signal to reset the external device; the A_IC pin and B_IC pin, as signal output terminals, send control signals to other modules in this circuit to achieve function drive, switch the working mode of the sensor, and control the start and stop of the motor. Finally, through the two-way interaction of the input and output interfaces, the collaborative work between the ADI chip U2 and the external device is completed.

[0035] This part is the peripheral circuit of the resolver decoding chip. U2 in it is the AD2S1205WSTZ of ADI, which is specifically used to decode the SIN signal and COS signal returned by the resolver and can convert them into data such as angles for the ADI chip U2 to parse. This chip can communicate with the MCU through the SPI protocol. Among them, pin 7 is the data pin of SPI, and pin 8 is the clock pin of SPI. It can also be output in the ABZ mode. Among them, pin 25 is the A pulse, pin 26 is the B pulse, and pin 28 is the output direction pin. Its pins 29 and 30 are the working status pins. If a fault occurs, the two light-emitting diodes will flash or be constantly on. The excitation outputs of the chip are pins 34 and 35, and it will output a 10kHz sine wave with a peak-to-peak value of 5V. Pins 37 and 38 are the SIN signal input pins, and pins 40 and 41 are the COS signal input pins. These signals are obtained from the resolver sensor to get the SIN signal.

[0036] The high-current op-amp and input / output circuit includes: a power supply circuit, an op-amp processing circuit, an isolation circuit, and a signal conditioning output circuit.

[0037] The power supply circuit is connected to the main control circuit and the op-amp processing circuit. The main control circuit is connected to the op-amp processing circuit and the signal conditioning circuit. The op-amp processing circuit is connected to the isolation circuit.

[0038] The power supply circuit includes capacitors C20, C21, C22, C23, resistors R29, R30, and R31.

[0039] One end of capacitor C20 is connected to the input power supply +11V, and the other end of capacitor C20 is connected to the ground. Capacitors C21 and C22 are connected in parallel across capacitor C20.

[0040] One end of resistor R29 is connected to the input power supply +5V, the other end of resistor R29 is connected to one end of capacitor C23, the other end of capacitor C23 is connected to ground, and resistors R30 and R31 are connected in parallel across capacitor C23.

[0041] The input power supply +11V is filtered by capacitors C20, C21, and C22 to suppress voltage ripple and supply power to circuits such as the operational amplifier; after the input power supply +5V is filtered by capacitor C23, it forms a voltage dividing circuit in cooperation with resistors R29, R30, and R31 to generate a reference voltage and provide a stable reference level for signal processing.

[0042] The operational amplifier processing circuit includes: resistors R19, R20, R21, R22, R22, 23, 24, 25, 26, 27, 28, capacitors C15, C16, and operational amplifier U3.

[0043] Pin EXC of ADI chip U2 is connected to one end of resistor R19, the other end of resistor R19 is connected to one end of resistor R20, the other end of resistor R20 is connected to one end of resistor R21 and pin InputsA- of operational amplifier U3, the other end of resistor R21 is connected to one end of resistor R22, the other end of resistor R22 is connected to pin OutputA of operational amplifier U3, capacitor C15 is connected in parallel across resistor R21, resistor R23 is connected in parallel across resistor R22, pin NC of the eleventh pin of operational amplifier U3, pin VEE-GND of the twelfth pin of operational amplifier U3, pin VEE-GND of the thirteenth pin of operational amplifier U3, pin NC of the fourteenth pin of operational amplifier U3, and pin NC of the fifteenth pin of operational amplifier U3 are connected to ground.

[0044] Pin EXC# of ADI chip U2 is connected to one end of resistor R24, the other end of resistor R24 is connected to one end of resistor R25, the other end of resistor R25 is connected to one end of resistor R26 and pin InputsB- of operational amplifier U3, the other end of resistor R26 is connected to one end of resistor R27, the other end of resistor R27 is connected to pin OutputB of operational amplifier U3, capacitor C16 is connected in parallel across resistor R26, resistor R28 is connected in parallel across resistor R27, pin NC of the sixth pin of operational amplifier U3, pin VEE-GND of the fifth pin of operational amplifier U3, pin VEE-GND of the fourth pin of operational amplifier U3, pin NC of the third pin of operational amplifier U3 are connected to ground, and pin VCC of operational amplifier U3 is connected to the input power supply +11V.

[0045] The excitation signal is preliminarily filtered by resistor R19 and capacitor C15 and then input into operational amplifier U3. The amplification factor is set through peripheral resistors such as resistor R22 and resistor R23 to adjust the signal amplitude. The operational amplifier processes the input signal into an excitation signal suitable for subsequent transmission to ensure that the resolver obtains a stable excitation source.

[0046] The isolation circuit includes: transformer L2, capacitor C17, capacitor C18, capacitor C19, diode D4.

[0047] The first pin of transformer L2 is connected to one end of resistor R23, the second pin of transformer L2 is connected to one end of resistor R28, the third pin of transformer L2 is connected to one end of capacitor C17, one end of capacitor C19, and the second pin of diode D4. The fourth pin of transformer L2 is connected to the other end of capacitor C17, one end of capacitor C18, and the first pin of diode D4. The other end of capacitor C18 is connected to the other end of capacitor C19, the third pin of diode D4, and ground.

[0048] Transformer L2 magnetically isolates the excitation signal output by the operational amplifier, blocks DC interference, and ensures the pure transmission of the excitation signal.

[0049] Diode D4 feeds back the state of the excitation signal, isolates the high-voltage and low-voltage circuits through optoelectronic conversion, and avoids interference from reversely affecting the front-stage circuit.

[0050] The signal conditioning circuit includes: resistor 32, resistor 33, resistor R34, resistor 35, resistor R36, capacitor C24, capacitor C25, capacitor C26, capacitor C27, capacitor C28, capacitor C29, transformer L3, diode D5, resistor 37, resistor 38, resistor R39, resistor 40, resistor R41, capacitor C30, capacitor C31, capacitor C32, capacitor C33, capacitor C34, capacitor C35, transformer L4, diode D6.

[0051] The reference voltage 2.5VREF is connected to one end of resistor R33 and one end of resistor R34. The other end of resistor R33 is connected to one end of resistor R32, the SIN pin of ADI chip U2, one end of resistor R35, and one end of capacitor C25. The other end of resistor R35 is connected to one end of capacitor C27 and the first pin of transformer L3. The other end of capacitor C27 is connected to one end of resistor R36 and the second pin of transformer L3. The other end of resistor R36 is connected to the other end of resistor R34, one end of capacitor C26, the other end of resistor R32, and the SINLO pin of ADI chip U2. Capacitor C24 is connected in parallel across resistor R32. The other end of capacitor C25 is connected to the other end of capacitor C26 and ground. The third pin of transformer L3 is connected to one end of capacitor C29 and the first pin of diode D5. The fourth pin of transformer L3 is connected to one end of capacitor C28 and the second pin of diode D5. The other end of capacitor C28 is connected to the other end of capacitor C29, the third pin of diode D5, and ground.

[0052] The reference voltage 2.5VREF is connected to one end of resistor R38 and one end of resistor R39. The other end of resistor R38 is connected to one end of resistor R37, the COS pin of ADI chip U2, one end of resistor R40, and one end of capacitor C31. The other end of resistor R40 is connected to one end of capacitor C33 and the first pin of transformer L4. The other end of capacitor C33 is connected to one end of resistor R41 and the second pin of transformer L4. The other end of resistor R41 is connected to the other end of resistor R39, one end of capacitor C32, the other end of resistor R37, and the COSLO pin of ADI chip U2. Capacitor C30 is connected in parallel across resistor R37. The other end of capacitor C31 is connected to the other end of capacitor C32 and ground. The third pin of transformer L4 is connected to one end of capacitor C35 and the first pin of diode D6. The fourth pin of transformer L4 is connected to one end of capacitor C34 and the second pin of diode D6. The other end of capacitor C34 is connected to the other end of capacitor C35, the third pin of diode D6, and ground.

[0053] Isolation and protection: External interference is isolated through transformers L3 and L4, and signal overvoltage protection is achieved in combination with diodes D5 and D6; the final output is SIN - differential signal, SIN + differential signal, COS - differential signal, COS + differential signal, ensuring that the ADI chip U2 obtains a stable and low - interference input signal.

[0054] The operational amplifier U3 in this circuit is a TCA0372DWR2G, which is a high-current operational amplifier. While it can amplify the excitation signal, it can also provide sufficient power to drive the resolver. The diodes D4, D5, and D6 at the input terminals of the SIN signal, COS signal, and EXC signal are TVS diodes, which can protect the subsequent stage from being damaged by spike voltages or interference. Filter circuits are added at the SIN signal and COS signal.

[0055] The present invention uses a power supply chip capable of current-limiting hiccup protection to monitor and protect the current of the resolver decoding system. While it can provide sufficient power, it can also effectively protect the resolver decoding system to prevent damage under harsh working conditions.

[0056] Although the present invention has been described in detail with reference to the foregoing embodiments, for those skilled in the art, they can still modify the technical solutions recorded in the foregoing embodiments, or perform equivalent replacements for some of the technical features. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.

Claims

1. A resolver decoding excitation output short-circuit protection circuit for a new energy vehicle, characterized in that, It includes: a current-limiting protection power supply circuit, a resolver decoding chip circuit, a high-current operational amplifier and an input / output circuit; The high-current operational amplifier and input / output circuit is connected to the current-limiting protection power supply circuit and the resolver decoding chip circuit.

2. The resolver decoding excitation output short-circuit protection circuit for a new energy vehicle according to claim 1, characterized in that, The current-limiting protection power supply circuit includes: resistor R1, resistor R2, resistor R3, resistor R4, resistor R5, resistor R6, resistor R7, resistor R8, capacitor C1, capacitor C2, capacitor C3, capacitor C4, capacitor C5, capacitor C6, capacitor C7, capacitor C8, capacitor C9, diode D1, diode D2, diode D3, inductor L1, power supply chip U1; One end of capacitor C1 is connected to the input power supply +12V, the first pin VIN of power supply chip U1, the ninth pin VIN of power supply chip U1, and one end of resistor R1. The other end of capacitor C1 is connected to the pin GND of power supply chip U1 and the ground. Capacitors C2, C3, and C4 are connected in parallel across capacitor C1. The other end of resistor R1 is connected to the pin EN of power supply chip U1; The pin IS of power supply chip U1 is connected to one end of resistor R3. The other end of resistor R3 is connected to the pin VS of power supply chip U1, one end of inductor L1, one end of capacitor C5, and the cathode of diode D2. Resistor R2 is connected in parallel across resistor R3. The other end of capacitor C5 is connected to the pin VB of power supply chip U1 and the anode of diode D1. The cathode of diode D1 is connected to the cathode of diode D3. The anode of diode D3 is connected to one end of resistor R4. The other end of resistor R4 is connected to the other end of inductor L1, one end of resistor R5, and one end of capacitor C6. The other end of resistor R5 is connected to one end of resistor R7, one end of resistor R6, the other end of capacitor C6, and the pin FB of power supply chip U1. The other end of resistor R7 is connected to the other end of resistor R6, the anode of diode D2, and the ground. One end of capacitor C7 is connected to one end of resistor R5 and the output power supply +11V. The other end of capacitor C7 is connected to the ground. Capacitors C8, C9, and resistor R8 are connected in parallel across capacitor C7; The power supply chip U1 has a current-limiting function.

3. The resolver decoding excitation output short-circuit protection circuit for a new energy vehicle according to claim 1, characterized in that, The resolver decoding chip circuit includes: a main control circuit and an interface circuit; The main control circuit is connected to the interface circuit.

4. The resolver decoding excitation output short-circuit protection circuit for a new energy vehicle according to claim 3, characterized in that, The main control chip includes: ADI chip U2, resistor R9, resistor R10, resistor R11, capacitor C10, capacitor C11, capacitor C12, capacitor C13, capacitor C14, fuse X1, light-emitting diode LED1, light-emitting diode LED2; The input power supply +5V is connected to the first pin DVDD of ADI chip U2 and the pin RDVEL# of ADI chip U2. The pin SOE# of DI chip U2 is connected to the ground. One end of resistor R9 is connected to the pin XTALOUT of ADI chip U2 and one end of capacitor C10. The other end of resistor R9 is connected to the pin CLKIN of ADI chip U2 and one end of capacitor C11. Fuse X1 is connected in parallel across resistor R9. The other end of capacitor C10 is connected to the other end of capacitor C11 and the ground; The REFOUT pin of the ADI chip U2 is connected to one end of the capacitor C12. The other end of the capacitor C12 is connected to one end of the capacitor C14, the forty-second pin AGND of the ADI chip U2, and the ground. The other end of the capacitor C14 is connected to the REFBYP pin of the ADI chip U2. The capacitor C13 is connected in parallel across the two ends of the capacitor C14. The AVDD pin of the ADI chip U2 is connected to the ground. The thirty-sixth pin AGND of the ADI chip U2 is connected to the ground. The LOT pin of the ADI chip U2 is connected to one end of the resistor R11. The other end of the resistor R11 is connected to the cathode of the light-emitting diode LED2. The DOS pin of the ADI chip U2 is connected to one end of the resistor R10. The other end of the resistor R10 is connected to the cathode of the light-emitting diode LED1. The anode of the light-emitting diode LED2 is connected to the anode of the light-emitting diode LED1 and the input power supply +5V. The DGND pin of the ADI chip U2 is connected to the ground.

5. The resolver decoding excitation output short-circuit protection circuit for a new energy vehicle according to claim 4, characterized in that, The interface circuit includes: resistors R12, R13, R14, R15, R16, R17, R18; The input power supply +5V is connected to one end of the resistors R12, R13, R14, R15, R16, R17, R18. The other end of the resistor R12 is connected to the SAMPLE# pin of the ADI chip U2. The other end of the resistor R13 is connected to the DB10 / SCLK pin of the ADI chip U2. The other end of the resistor R14 is connected to the DIR pin of the ADI chip U2. The other end of the resistor R15 is connected to the A pin of the ADI chip U2. The other end of the resistor R16 is connected to the B pin of the ADI chip U2. The other end of the resistor R17 is connected to the RESET# pin of the ADI chip U2. The other end of the resistor R18 is connected to the RD pin of the ADI chip U2.

6. The resolver decoding excitation output short - circuit protection circuit for a new - energy vehicle according to claim 4, characterized in that, The high-current operational amplifier and input / output circuit includes: a power supply circuit, an operational amplifier processing circuit, an isolation circuit, and a signal conditioning output circuit; The power supply circuit is connected to the main control circuit and the operational amplifier processing circuit. The main control circuit is connected to the operational amplifier processing circuit and the signal conditioning circuit. The operational amplifier processing circuit is connected to the isolation circuit.

7. The resolver decoding excitation output short-circuit protection circuit for a new energy vehicle according to claim 6, characterized in that, The power supply circuit includes capacitors C20, C21, C22, C23, resistors R29, R30, R31; One end of the capacitor C20 is connected to the input power supply +11V. The other end of the capacitor C20 is connected to the ground. The capacitors C21 and C22 are connected in parallel across the two ends of the capacitor C20; One end of the resistor R29 is connected to the input power supply +5V. The other end of the resistor R29 is connected to one end of the capacitor C23. The other end of the capacitor C23 is connected to the ground. The resistors R30 and R31 are connected in parallel across the two ends of the capacitor C23.

8. The resolver decoding excitation output short-circuit protection circuit for a new energy vehicle according to claim 6, characterized in that, The operational amplifier processing circuit includes: resistors R19, R20, R21, R22, R22, 23, 24, 25, 26, 27, 28, capacitors C15, C16, and operational amplifier U3; The pin EXC of the ADI chip U2 is connected to one end of the resistor R19. The other end of the resistor R19 is connected to one end of the resistor R20. The other end of the resistor R20 is connected to one end of the resistor R21 and the pin InputsA- of the operational amplifier U3. The other end of the resistor R21 is connected to one end of the resistor R22. The other end of the resistor R22 is connected to the pin OutputA of the operational amplifier U3. The capacitor C15 is connected in parallel across the resistor R21. The resistor R23 is connected in parallel across the resistor R22. The eleventh pin NC of the operational amplifier U3, the twelfth pin VEE - GND of the operational amplifier U3, the thirteenth pin VEE - GND of the operational amplifier U3, the fourteenth pin NC of the operational amplifier U3, and the fifteenth pin NC of the operational amplifier U3 are connected to the ground. The pin EXC# of the ADI chip U2 is connected to one end of the resistor R24. The other end of the resistor R24 is connected to one end of the resistor R25. The other end of the resistor R25 is connected to one end of the resistor R26 and the pin InputsB- of the operational amplifier U3. The other end of the resistor R26 is connected to one end of the resistor R27. The other end of the resistor R27 is connected to the pin OutputB of the operational amplifier U3. The capacitor C16 is connected in parallel across the resistor R26. The resistor R28 is connected in parallel across the resistor R27. The sixth pin NC of the operational amplifier U3, the fifth pin VEE - GND of the operational amplifier U3, the fourth pin VEE - GND of the operational amplifier U3, the third pin NC of the operational amplifier U3 are connected to the ground, and the pin VCC of the operational amplifier U3 is connected to the input power supply +11V.

9. The resolver decoding excitation output short-circuit protection circuit for a new energy vehicle according to claim 8, characterized in that The isolation circuit includes: transformer L2, capacitor C17, capacitor C18, capacitor C19, diode D4. The first pin of the transformer L2 is connected to one end of the resistor R23. The second pin of the transformer L2 is connected to one end of the resistor R28. The third pin of the transformer L2 is connected to one end of the capacitor C17, one end of the capacitor C19, and the second pin of the diode D4. The fourth pin of the transformer L2 is connected to the other end of the capacitor C17, one end of the capacitor C18, and the first pin of the diode D4. The other end of the capacitor C18 is connected to the other end of the capacitor C19, the third pin of the diode D4, and the ground.

10. The resolver decoding excitation output short - circuit protection circuit for a new - energy vehicle according to claim 6, wherein, The signal conditioning circuit includes: resistor 32, resistor 33, resistor R34, resistor 35, resistor R36, capacitor C24, capacitor C25, capacitor C26, capacitor C27, capacitor C28, capacitor C29, transformer L3, diode D5, resistor 37, resistor 38, resistor R39, resistor 40, resistor R41, capacitor C30, capacitor C31, capacitor C32, capacitor C33, capacitor C34, capacitor C35, transformer L4, diode D6. The reference voltage 2.5VREF is connected to one end of resistor R33 and one end of resistor R34. The other end of resistor R33 is connected to one end of resistor R32, the SIN pin of ADI chip U2, one end of resistor R35, and one end of capacitor C25. The other end of resistor R35 is connected to one end of capacitor C27 and the first pin of transformer L3. The other end of capacitor C27 is connected to one end of resistor R36 and the second pin of transformer L3. The other end of resistor R36 is connected to the other end of resistor R34, one end of capacitor C26, the other end of resistor R32, and the SINLO pin of ADI chip U2. Capacitor C24 is connected in parallel across resistor R32. The other end of capacitor C25 is connected to the other end of capacitor C26 and ground. The third pin of transformer L3 is connected to one end of capacitor C29 and the first pin of diode D5. The fourth pin of transformer L3 is connected to one end of capacitor C28 and the second pin of diode D6. The other end of capacitor C28 is connected to the other end of capacitor C29, the third pin of diode D5, and ground; The reference voltage 2.5VREF is connected to one end of resistor R38 and one end of resistor R39. The other end of resistor R38 is connected to one end of resistor R37, the COS pin of ADI chip U2, one end of resistor R40, and one end of capacitor C31. The other end of resistor R40 is connected to one end of capacitor C33 and the first pin of transformer L4. The other end of capacitor C33 is connected to one end of resistor R41 and the second pin of transformer L4. The other end of resistor R41 is connected to the other end of resistor R39, one end of capacitor C32, the other end of resistor R37, and the COSLO pin of ADI chip U2. Capacitor C30 is connected in parallel across resistor R37. The other end of capacitor C31 is connected to the other end of capacitor C32 and ground. The third pin of transformer L4 is connected to one end of capacitor C35 and the first pin of diode D6. The fourth pin of transformer L4 is connected to one end of capacitor C34 and the second pin of diode D6. The other end of capacitor C34 is connected to the other end of capacitor C35, the third pin of diode D6, and ground.

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