New energy vehicle resolver decoding excitation output short circuit protection circuit

Abstract

The utility model discloses a new energy automobile rotary transformer decoding excitation output short circuit protection circuit, including: with current -limiting protection power supply circuit, rotary transformer decoding chip circuit, large -current operational amplifier and output input circuit, large -current operational amplifier and output input circuit are connected with current -limiting protection power supply circuit, rotary transformer decoding chip circuit, the utility model for using a current -limiting protection power supply chip that can carry out belching to the current of rotary transformer decoding system carries out monitoring protection, can provide sufficient power simultaneously, can also carry out effective protection to rotary transformer decoding system, prevent and appear bad working condition damage.

Description

Technical Field

[0001] This utility model belongs to the field of short-circuit protection circuit technology, and relates to a short-circuit protection circuit for the excitation output of a resolver decoder in a new energy vehicle. Background Technology

[0002] In new energy vehicles, resolvers are currently the mainstream sensors for measuring the angular displacement and angular velocity of the motor. They require a 10kHz or 5kHz sine wave excitation to operate. However, the excitation signal output by typical resolver decoding chips is too weak, making the resolver's output signal susceptible to interference. Therefore, an operational amplifier is needed to amplify the excitation signal and enhance its anti-interference capability. The higher the amplification level of the excitation signal, the higher the output capability of the operational amplifier is required. However, if the excitation is short-circuited, the short-circuit current becomes significantly larger, often leading to the burnout of the excitation's output resistor or the operational amplifier due to the large current.

[0003] Currently, most resolver decoding systems use a push-pull circuit following a standard operational amplifier as the excitation output to ensure sufficient power. Many resolver decoding systems lack excitation output protection; they either stack output resistors to artificially withstand high currents or suffer direct damage from short circuits. Therefore, an excitation output short-circuit protection circuit is needed to protect the excitation output from damage in the event of resolver failure or short circuits. Summary of the Invention

[0004] To address the problems existing in the background technology, this utility model proposes a short-circuit protection circuit for the excitation output of a resolver decoder in new energy vehicles.

[0005] To achieve the above objectives, the technical solution adopted by this utility model is as follows: a short-circuit protection circuit for the excitation output of a resolver decoder for new energy vehicles, comprising: a power supply circuit with current limiting protection, a resolver decoder chip circuit, a high-current operational amplifier, and an output and input circuit;

[0006] The high-current operational amplifier and its input / output circuits are connected to the power supply circuit with current limiting protection and the resolver decoding chip circuit.

[0007] The power supply circuit with current limiting protection includes: resistors R1, R2, R3, R4, R5, R6, R7, and R8; capacitors C1, C2, C3, C4, C5, C6, C7, C8, and C9; diodes D1, D2, and D3; inductor L1; and power chip U1.

[0008] One end of capacitor C1 is connected to the input power supply +12V, the first pin VIN of power chip U1, the ninth pin VIN of power chip U1, and one end of resistor R1. The other end of capacitor C1 is connected to the pin GND of power chip U1 and 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 chip U1.

[0009] Pin IS of power chip U1 is connected to one end of resistor R3. The other end of resistor R3 is connected to pin VS of power chip U1, one end of inductor L1, one end of capacitor C5, and the negative terminal of diode D2. Resistor R2 is connected in parallel across resistor R3. The other end of capacitor C5 is connected to pin VB of power chip U1 and the positive terminal of diode D1. The negative terminal of diode D1 is connected to the negative terminal of diode D3. The positive terminal 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 pin FB of power chip U1. The other end of resistor R7 is connected to the other end of resistor R6, the positive terminal of diode D2, and 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 ground. Capacitors C8 and C9 and resistor R8 are connected in parallel across capacitor C7.

[0010] The power chip U1 has a current limiting function, which can monitor the current flowing through it. The current limiting protection hiccup mode of the power chip has a restart time on the order of seconds, which can reduce its own heat generation during short circuits.

[0011] The resolver decoding chip circuit includes: main control circuit and interface circuit;

[0012] The main control circuit is connected to the interface circuit.

[0013] The main control chip includes: ADI chip U2, resistors R9, R10, R11, capacitors C10, C11, C12, C13, C14, fuse X1, LED1, and LED2.

[0014] The input power supply +5V is connected to the first pin DVDD and the pin RDVEL# of the ADI chip U2. The pin SOE# of the ADI chip U2 is connected to 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 on both sides of the resistor R9. The other end of the capacitor C10 is connected to the other end of the capacitor C11 and ground.

[0015] The REFOUT pin of ADI chip U2 is connected to one end of capacitor C12. The other end of capacitor C12 is connected to one end of capacitor C14, pin AGND of ADI chip U2 (42nd pin), and ground. The other end of capacitor C14 is connected to the REFBYP pin of ADI chip U2. Capacitor C13 is connected in parallel across capacitor C14. The AVDD pin of ADI chip U2 is connected to ground. The AGND pin of ADI chip U2 (36th pin) is connected to ground. The LOT pin of ADI chip U2 is connected to one end of resistor R11. The other end of resistor R11 is connected to the negative terminal of LED2. The DOS pin of ADI chip U2 is connected to one end of resistor R10. The other end of resistor R10 is connected to the negative terminal of LED1. The positive terminal of LED2 is connected to the positive terminal of LED1 and the +5V input power supply. The DGND pin of ADI chip U2 is connected to ground.

[0016] The interface circuit includes: resistors R12, R13, R14, R15, R16, R17, and R18.

[0017] Connect the +5V input power supply to one end of resistors R12, R13, R14, R15, R16, R17, and R18. Connect the other end of resistor R12 to pin SAMPLE# of ADI chip U2, the other end of resistor R13 to pin DB10 / SCLK of ADI chip U2, the other end of resistor R14 to pin DIR of ADI chip U2, the other end of resistor R15 to pin A of ADI chip U2, the other end of resistor R16 to pin B of ADI chip U2, the other end of resistor R17 to pin RESET# of ADI chip U2, and the other end of resistor R18 to pin RD of ADI chip U2.

[0018] The high-current operational amplifier and its input / output circuitry include: power supply circuitry, operational amplifier processing circuitry, isolation circuitry, and signal conditioning output circuitry.

[0019] 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.

[0020] The power supply circuit includes capacitors C20, C21, C22, and C23, and resistors R29, R30, and R31.

[0021] One end of capacitor C20 is connected to the input power supply +11V, and the other end of capacitor C20 is connected to ground. Capacitors C21 and C22 are connected in parallel across capacitor C20.

[0022] One end of resistor R29 is connected to the input power supply +5V, and the other end of resistor R29 is connected to one end of capacitor C23. The other end of capacitor C23 is connected to ground. Resistors R30 and R31 are connected in parallel across capacitor C23.

[0023] The operational amplifier processing circuit includes: resistors R19, R20, R21, R22, R22, R23, R24, R25, R26, R27, R28, capacitors C15 and C16, and operational amplifier U3.

[0024] 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. Pins 11 (NC), 12 (VEE-GND), 13 (VEE-GND), 14 (NC), and 15 (NC) of operational amplifier U3 are connected to ground.

[0025] 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. Pins NC, VEE-GND, VEE-GND, and NC of operational amplifier U3 are connected to ground. Pin VCC of operational amplifier U3 is connected to the +11V input power supply.

[0026] The isolation circuit includes: transformer L2, capacitor C17, capacitor C18, capacitor C19, and diode D4;

[0027] 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.

[0028] The signal conditioning circuit includes: resistors R32, R33, R34, R35, R36, capacitors C24, C25, C26, C27, C28, C29, transformer L3, diode D5, resistors R37, R38, R39, R40, R41, capacitors C30, C31, C32, C33, C34, C35, transformer L4, and diode D6;

[0029] 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, pin SIN 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 pin SINLO 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.

[0030] 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, pin COS 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 pin COSLO 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.

[0031] Furthermore,

[0032] Compared with the prior art, the present invention has the following beneficial effects:

[0033] A high-power operational amplifier is used instead of the traditional push-pull circuit, reducing cost and PCB space. A power supply chip with current limiting protection, or one added before or after a power supply chip without current limiting protection, is used to detect the current in the resolver decoding system and take protective action to prevent overheating and damage to the resolver decoding chip due to abnormal operating conditions. The system achieves both voltage and current adjustment, implementing current limiting protection at certain current levels to protect the resolver decoding system. Alternatively, a current limiting protection chip can be added before or after a power supply chip without current limiting protection to detect the current entering the resolver decoding system. If abnormal current is detected, the power supply chip is switched on and off to achieve protection. Attached Figure Description

[0034] Figure 1 This is a block diagram of a short-circuit protection circuit for a resolver decoder excitation in a new energy vehicle.

[0035] Figure 2 This is a circuit block diagram of the short-circuit protection circuit for the decoder excitation of a new energy vehicle.

[0036] Figure 3 This is the circuit connection diagram of the power supply with current limiting protection of this utility model;

[0037] Figure 4 This is a circuit connection diagram of the resolver decoding chip of this utility model;

[0038] Figure 5 This is a connection diagram of the high-current operational amplifier and its output / input circuit of this utility model. Detailed Implementation

[0039] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0040] like Figures 1-5 As shown, the technical solution adopted by this utility model is as follows: a short-circuit protection circuit for the excitation output of a resolver decoder for new energy vehicles, comprising: a power supply circuit with current limiting protection, a resolver decoder chip circuit, a high-current operational amplifier, and an output and input circuit.

[0041] The high-current operational amplifier and its input / output circuits are connected to the power supply circuit with current limiting protection and the resolver decoding chip circuit.

[0042] The power supply circuit with current limiting protection includes: resistors R1, R2, R3, R4, R5, R6, R7, and R8; capacitors C1, C2, C3, C4, C5, C6, C7, C8, and C9; diodes D1, D2, and D3; inductor L1; and power chip U1.

[0043] One end of capacitor C1 is connected to the input power supply +12V, the first pin VIN of power chip U1, the ninth pin VIN of power chip U1, and one end of resistor R1. The other end of capacitor C1 is connected to the pin GND of power chip U1 and 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 chip U1.

[0044] Pin IS of power chip U1 is connected to one end of resistor R3. The other end of resistor R3 is connected to pin VS of power chip U1, one end of inductor L1, one end of capacitor C5, and the negative terminal of diode D2. Resistor R2 is connected in parallel across resistor R3. The other end of capacitor C5 is connected to pin VB of power chip U1 and the positive terminal of diode D1. The negative terminal of diode D1 is connected to the negative terminal of diode D3. The positive terminal 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 pin FB of power chip U1. The other end of resistor R7 is connected to the other end of resistor R6, the positive terminal of diode D2, and ground. One end of capacitor C7 is connected to one end of resistor R5 and the +11V output power supply. The other end of capacitor C7 is connected to ground. Capacitors C8 and C9 and resistor R8 are connected in parallel across capacitor C7.

[0045] The power chip U1 is an EG1192H with current limiting functionality. It monitors the current flowing through it and provides current-limiting protection. Its current-limiting protection hiccup mode restart time is on the order of seconds, reducing heat generation during short circuits. Resistors R2 and R3 are current-limiting sampling resistors, which perform current-limiting protection by detecting the peak current flowing through the internal MOSFET. It is also an adjustable power supply; the output voltage can be adjusted via a voltage divider using the FB pin of the power chip U1 and external resistors R5, R6, and R7. Therefore, it offers both voltage and current adjustment capabilities.

[0046] Resistors R2 and R3 form a feedback voltage divider circuit, which samples the output voltage and feeds it back to the feedback pin of the power chip U1 to ensure that the output voltage is stable at the set value.

[0047] After the +12V power input, it first passes through a filter circuit composed of capacitors C1, C2, and C3 to filter out high-frequency noise and stabilize the input voltage. Resistor R1 acts as a current limiter or voltage divider to protect the input pin of power chip U1 from abnormal current surges. Power chip U1, as the core of the DC-DC converter, controls diode D1 to periodically conduct or cut off: when diode D1 is on, the +12V power input charges inductor L1 to store energy; when diode D1 is off, inductor L1 releases energy to maintain the output current. Resistors R2 and R3 at the output terminal sample the +11V output voltage and provide feedback to the feedback pin of power chip U1 through diode D1. Power chip U1 adjusts the duty cycle of diode D1 according to the feedback signal to ensure stable output voltage. During this process, diodes D2 and D3, along with resistor R4, assist in processing the feedback signal. Finally, inductor L1, along with capacitors C4, C5, and C6, form a filter circuit to filter out voltage ripple, ensuring a smooth and stable +11V DC output voltage to power the downstream load.

[0048] The resolver decoding chip circuit includes: main control circuit and interface circuit.

[0049] The main control circuit is connected to the interface circuit.

[0050] The main control chip includes: ADI chip U2, resistors R9, R10, and R11, capacitors C10, C11, C12, C13, and C14, fuse X1, LED1, and LED2.

[0051] The input power supply +5V is connected to the first pin DVDD and the pin RDVEL# of the ADI chip U2. The pin SOE# of the ADI chip U2 is connected to 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 on both sides of the resistor R9. The other end of the capacitor C10 is connected to the other end of the capacitor C11 and ground.

[0052] The REFOUT pin of ADI chip U2 is connected to one end of capacitor C12. The other end of capacitor C12 is connected to one end of capacitor C14, pin AGND of ADI chip U2 (42nd pin), and ground. The other end of capacitor C14 is connected to the REFBYP pin of ADI chip U2. Capacitor C13 is connected in parallel across capacitor C14. The AVDD pin of ADI chip U2 is connected to ground. The AGND pin of ADI chip U2 (36th pin) is connected to ground. The LOT pin of ADI chip U2 is connected to one end of resistor R11. The other end of resistor R11 is connected to the negative terminal of LED2. The DOS pin of ADI chip U2 is connected to one end of resistor R10. The other end of resistor R10 is connected to the negative terminal of LED1. The positive terminal of LED2 is connected to the positive terminal of LED1 and the +5V input power supply. The DGND pin of ADI chip U2 is connected to ground.

[0053] The +5V input power supply powers the ADI chip U2 via pins such as DVDD. Capacitors C10 and C11, along with the crystal oscillator, form a clock circuit. A stable clock is input via pins such as CLKIN to ensure the normal operation of the ADI chip U2's timing logic. Data interaction relies on the DB0-DB10 data bus, along with read and write control pins, to coordinate the data read / write timing with external memory devices. For external signal processing, input pins such as the sampling trigger pin and synchronization clock pin receive external sampling commands and synchronization signals to drive the chip to process data; output pins such as the A_IC pin and B_IC pin send control signals to external actuators. LEDs LED1 and LED2, with current limited by resistors R10 and R11, indicate the real-time operating status of the ADI chip U2.

[0054] The interface circuit includes: resistors R12, R13, R14, R15, R16, R17, and R18.

[0055] Connect the +5V input power supply to one end of resistors R12, R13, R14, R15, R16, R17, and R18. Connect the other end of resistor R12 to pin SAMPLE# of ADI chip U2, the other end of resistor R13 to pin DB10 / SCLK of ADI chip U2, the other end of resistor R14 to pin DIR of ADI chip U2, the other end of resistor R15 to pin A of ADI chip U2, the other end of resistor R16 to pin B of ADI chip U2, the other end of resistor R17 to pin RESET# of ADI chip U2, and the other end of resistor R18 to pin RD of ADI chip U2.

[0056] 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 sampling trigger commands from external master devices to start chip data acquisition; the SCLK_IC pin obtains a synchronization clock to ensure accurate data transmission timing; and the DIR_IC pin can receive direction control signals to set the data transmission direction. Pins such as A_IC, B_IC, and RST_IC are output interfaces that output the chip's processing results. The RST_IC pin can send a reset signal to reset external devices; the A_IC and B_IC pins serve as signal output terminals, sending control signals to other modules in the circuit to achieve function driving, switch sensor operating modes, control motor start and stop, and ultimately complete the collaborative work between the ADI chip U2 and external devices through bidirectional interaction of the input / output interfaces.

[0057] This section describes the peripheral circuitry of the resolver decoding chip. U2, an ADI AD2S1205WSTZ chip, is specifically designed to decode the SIN and COS signals returned from the resolver, converting them into angle and other data for analysis by the ADI chip U2. This chip can communicate with the MCU via the SPI protocol. Pin 7 is the SPI data pin, and pin 8 is the SPI clock pin. It can also output via ABZ mode, with pin 25 for the A pulse, pin 26 for the B pulse, and pin 28 for the output direction. Pins 29 and 30 are the operating status pins; in case of a fault, the two LEDs will flash or remain constantly lit. The chip's excitation outputs are pins 34 and 35, which 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 SIN signal of the resolver sensor.

[0058] The high-current operational amplifier and its input / output circuits include: power supply circuit, operational amplifier processing circuit, isolation circuit, and signal conditioning output circuit.

[0059] 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.

[0060] The power supply circuit includes capacitors C20, C21, C22, and C23, and resistors R29, R30, and R31.

[0061] One end of capacitor C20 is connected to the input power supply +11V, and the other end of capacitor C20 is connected to ground. Capacitors C21 and C22 are connected in parallel across capacitor C20.

[0062] One end of resistor R29 is connected to the input power supply +5V, and the other end of resistor R29 is connected to one end of capacitor C23. The other end of capacitor C23 is connected to ground. Resistors R30 and R31 are connected in parallel across capacitor C23.

[0063] The +11V input power supply is filtered by capacitors C20, C21, and C22 to suppress voltage ripple and power the op-amp and other circuits. The +5V input power supply is filtered by capacitor C23 and, together with the voltage divider circuit consisting of resistors R29, R30, and R31, generates a reference voltage to provide a stable reference level for signal processing.

[0064] The operational amplifier processing circuit includes: resistors R19, R20, R21, R22, R22, R23, R24, R25, R26, R27, R28, capacitors C15 and C16, and operational amplifier U3.

[0065] 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. Pins 11 (NC), 12 (VEE-GND), 13 (VEE-GND), 14 (NC), and 15 (NC) of operational amplifier U3 are connected to ground.

[0066] 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. Pins NC, VEE-GND, VEE-GND, and NC of operational amplifier U3 are connected to ground. Pin VCC of operational amplifier U3 is connected to the +11V input power supply.

[0067] The excitation signal is initially filtered by resistor R19 and capacitor C15 and then input to operational amplifier U3. The amplification factor is set by external resistors such as resistor R22 and resistor R23, and the signal amplitude is adjusted. The operational amplifier processes the input signal into an excitation signal suitable for subsequent transmission, ensuring that the rotary transformer obtains a stable excitation source.

[0068] The isolation circuit includes: transformer L2, capacitor C17, capacitor C18, capacitor C19, and diode D4.

[0069] 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.

[0070] Transformer L2 provides magnetic isolation for the excitation signal output by the operational amplifier, blocking DC interference and ensuring pure transmission of the excitation signal.

[0071] Diode D4 provides feedback on the excitation signal status and isolates the high and low voltage circuits through photoelectric conversion, preventing interference from affecting the preceding circuitry in the reverse direction.

[0072] The signal conditioning circuit includes: resistors 32, 33, R34, 35, and R36; capacitors C24, C25, C26, C27, C28, and C29; transformer L3; diode D5; resistors 37, 38, R39, 40, and R41; capacitors C30, C31, C32, C33, C34, and C35; transformer L4; and diode D6.

[0073] 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, pin SIN 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 pin SINLO 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.

[0074] 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, pin COS 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 pin COSLO 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.

[0075] Isolation and Protection: External interference is isolated by transformers L3 and L4, and signal overvoltage protection is achieved by diodes D5 and D6; finally, SIN- differential signal, SIN- differential signal+, COS- differential signal, and COS+ differential signal are output to ensure that the ADI chip U2 obtains a stable and low-interference input signal.

[0076] The operational amplifier U3 in this circuit is a TCA0372DWR2G, a high-current operational amplifier that can amplify the excitation signal while providing sufficient power to drive the resolver. Diodes D4, D5, and D6 at the SIN, COS, and EXC signal inputs are TVS diodes, protecting subsequent stages from damage caused by voltage spikes or interference. Filtering circuits are added at the SIN and COS signal inputs.

[0077] This invention uses a power chip capable of current limiting and hiccup protection to monitor and protect the current of the resolver decoding system. While providing sufficient power, it can also effectively protect the resolver decoding system and prevent damage from harsh operating conditions.

[0078] Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

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

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

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

4. The short-circuit protection circuit for the excitation output of a resolver decoder in a new energy vehicle according to claim 3, characterized in that, The main control chip includes: ADI chip U2, resistors R9, R10, R11, capacitors C10, C11, C12, C13, C14, fuse X1, LED1, and LED2. The input power supply +5V is connected to the first pin DVDD and the pin RDVEL# of the ADI chip U2. The pin SOE# of the ADI chip U2 is connected to 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 on both sides of the resistor R9. The other end of the capacitor C10 is connected to the other end of the capacitor C11 and ground. The REFOUT pin of ADI chip U2 is connected to one end of capacitor C12. The other end of capacitor C12 is connected to one end of capacitor C14, pin AGND of ADI chip U2 (42nd pin), and ground. The other end of capacitor C14 is connected to the REFBYP pin of ADI chip U2. Capacitor C13 is connected in parallel across capacitor C14. The AVDD pin of ADI chip U2 is connected to ground. The AGND pin of ADI chip U2 (36th pin) is connected to ground. The LOT pin of ADI chip U2 is connected to one end of resistor R11. The other end of resistor R11 is connected to the negative terminal of LED2. The DOS pin of ADI chip U2 is connected to one end of resistor R10. The other end of resistor R10 is connected to the negative terminal of LED1. The positive terminal of LED2 is connected to the positive terminal of LED1 and the +5V input power supply. The DGND pin of ADI chip U2 is connected to ground.

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

6. The short-circuit protection circuit for the excitation output of a resolver decoder in a new energy vehicle according to claim 4, characterized in that, The high-current operational amplifier and its input / output circuitry include: power supply circuitry, operational amplifier processing circuitry, isolation circuitry, and signal conditioning output circuitry. 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. A short-circuit protection circuit for the excitation output of a resolver decoder in a new energy vehicle according to claim 6, characterized in that, The power supply circuit includes capacitors C20, C21, C22, and C23, and resistors R29, R30, and R31. One end of capacitor C20 is connected to the input power supply +11V, and the other end of capacitor C20 is connected to ground. Capacitors C21 and C22 are connected in parallel across capacitor C20. One end of resistor R29 is connected to the input power supply +5V, and the other end of resistor R29 is connected to one end of capacitor C23. The other end of capacitor C23 is connected to ground. Resistors R30 and R31 are connected in parallel across capacitor C23.

8. A short-circuit protection circuit for the excitation output of a resolver decoder in a new energy vehicle according to claim 6, characterized in that, The operational amplifier processing circuit includes: resistors R19, R20, R21, R22, R23, R24, R25, R26, R27, R28, capacitors C15 and 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. Pins 11 (NC), 12 (VEE-GND), 13 (VEE-GND), 14 (NC), and 15 (NC) 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. Pins NC, VEE-GND, VEE-GND, and NC of operational amplifier U3 are connected to ground. Pin VCC of operational amplifier U3 is connected to the +11V input power supply.

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

10. A short-circuit protection circuit for the excitation output of a resolver decoder in a new energy vehicle according to claim 6, characterized in that, The signal conditioning circuit includes: resistors R32, R33, R34, R35, R36, capacitors C24, C25, C26, C27, C28, C29, transformer L3, diode D5, resistors R37, R38, R39, R40, R41, capacitors C30, C31, C32, C33, C34, C35, transformer L4, and 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, pin SIN 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 pin SINLO 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, pin COS 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 pin COSLO 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.

Images