An adaptive power delta encoder detection circuit

Abstract

The application discloses a kind of self-adapting power increment encoders detection circuit, belong to the signal detection technical field of encoder, comprising: power voltage detection judging circuit, control input circuit, difference conversion circuit, opto-coupler isolation circuit, isolated power supply circuit;Simplify the process of incremental encoder signal measurement, after connecting circuit, without adjusting any action of circuit, it can be self-adapting encoder different power supply, greatly save circuit design and matching time;And in the process of measurement adjustment, human factors are excluded, increase the reliability of signal measurement.

Description

Technical Field

[0001] This invention belongs to the field of encoder signal detection technology, and specifically relates to an adaptive power incremental encoder detection circuit. Background Technology

[0002] With the increasing prevalence of motor control and applications, motor speed is a crucial characteristic parameter, and its measurement is essential in various industrial production sectors. Common methods for obtaining motor speed include direct and indirect measurement. Direct measurement is relatively difficult, while indirect measurement encompasses various methods, including photoelectric encoder speed measurement, Hall element speed measurement, centrifugal speed measurement, flash speed measurement, and leakage flux speed measurement.

[0003] In the wind power sector, generator speed measurement typically employs photoelectric encoders. This method requires an incremental encoder to convert the generator displacement into a periodic electrical signal, which is then converted into counting pulses. The number of pulses represents the magnitude of the displacement. The mainstream encoder power supplies on the market are 24V, 15V, and 5V. Due to these different power supply levels, the measurement method requires circuit modifications and the selection of different components to address the input process, making it quite cumbersome. Furthermore, the operation introduces uncertainties such as human error, increasing the difficulty of measurement and potentially damaging board-level components. Summary of the Invention

[0004] To overcome the shortcomings of existing encoder detection technologies that cannot actively adapt to changes in power supply, this invention provides an adaptive power supply incremental encoder detection circuit that can be used for speed measurement of incremental encoders with different power supplies.

[0005] The technical solution adopted by this invention to solve its technical problem is: an adaptive power incremental encoder detection circuit, comprising: a power supply voltage detection and judgment circuit, a control input circuit, a differential conversion circuit, an optocoupler isolation circuit, and an isolated power supply circuit; the power supply voltage detection and judgment circuit is connected to the encoder power supply to receive the power supply signal of the encoder power supply, and the power supply voltage detection and judgment circuit is also connected to the control input circuit and outputs a control signal to the control input circuit; the control input circuit is connected to the encoder output signal terminal and the differential conversion circuit, the differential conversion circuit is connected to the optocoupler isolation circuit, the optocoupler isolation circuit is connected to the user system, the user system is connected to the isolated power supply circuit, and the isolated power supply circuit is connected to the power supply voltage detection and judgment circuit, the control input circuit, the differential conversion circuit, and the optocoupler isolation circuit respectively.

[0006] As a further embodiment of the present invention, after the user system powers on the isolated power supply circuit, the isolated power supply circuit generates power to supply the power supply voltage detection and judgment circuit, the control input circuit, the differential conversion circuit, and the optocoupler isolation circuit. After the encoder power supply powers on the encoder, the power supply voltage detection and judgment circuit compares the input power signal with the set comparison voltage. When the input power signals are different, it outputs different control signals to the control input circuit. The control input circuit adjusts the encoder signal level according to the input control signal. The adjusted encoder signal is transmitted to the differential conversion circuit for signal conversion. The converted signal is then isolated by the optocoupler isolation circuit before being connected to the user system.

[0007] As a further embodiment of the present invention, the comparison voltage is set to 2V and 4V.

[0008] As a further embodiment of the present invention, the control input circuit controls the solid-state relay according to the input control signal, turns on the load after the solid-state relay, adjusts the input matching resistor, and realizes the adjustment of the encoder signal level.

[0009] As a further embodiment of the present invention, the differential conversion circuit converts the encoder signal through four differential signal receivers.

[0010] As a further embodiment of the present invention, the differential conversion circuit outputs A, B, and Z phase signals, which are isolated by a high-speed optocoupler in the optocoupler isolation circuit.

[0011] The beneficial effects of this invention are: it simplifies the process of incremental encoder signal measurement; after connecting the circuit, no adjustment of the circuit is required, and it can adapt to different power supplies of the encoder, which greatly saves circuit design and matching time; and it eliminates human factors in the measurement and adjustment process, increasing the reliability of signal measurement. Attached Figure Description

[0012] Figure 1 This is a block diagram of the overall circuit structure of the present invention;

[0013] Figure 2 This is a schematic diagram of the power supply voltage detection and judgment circuit of the present invention;

[0014] Figure 3 This is a structural diagram of the control input circuit of the present invention;

[0015] Figure 4 This is a structural diagram of the differential conversion circuit and optocoupler isolation circuit of the present invention;

[0016] Figure 5 This is a structural diagram of the isolated power supply circuit of the present invention.

[0017] The following are the labels in the attached diagram: 1. Power supply voltage detection and judgment circuit; 2. Control input circuit; 3. Differential conversion circuit; 4. Optocoupler isolation circuit; 5. Isolation power supply circuit; 6. Encoder power supply; 7. Encoder; 8. User system. Detailed Implementation

[0018] The technical solution of the present invention will now be clearly and completely described with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0019] In the description of this invention, it should be noted that the terms "vertical," "horizontal," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing the invention and for simplifying the description, and do not indicate or imply that the device or component referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the invention. Furthermore, the terms "first," "second," and "third" are used only to distinguish components and should not be construed as indicating or implying relative importance.

[0020] Furthermore, the technical features involved in the different embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0021] Example 1

[0022] An adaptive power incremental encoder detection circuit includes a power supply voltage detection and judgment circuit 1, a control input circuit 2, a differential conversion circuit 3, an optocoupler isolation circuit 4, and an isolation power supply circuit 5.

[0023] like Figure 1 As shown, the power supply voltage detection and judgment circuit 1 is connected to the encoder power supply 6 to receive the power signal from the encoder power supply 6. The power supply voltage detection and judgment circuit 1 is also connected to the control input circuit 2 and outputs a control signal to the control input circuit 2. The control input circuit 2 is connected to the output signal terminal of the encoder 7 and the differential conversion circuit 3. The differential conversion circuit 3 is connected to the optocoupler isolation circuit 4, which is connected to the user system 8. The user system 8 is connected to the isolation power supply circuit 5, which is connected to the power supply voltage detection and judgment circuit 1, the control input circuit 2, the differential conversion circuit 3, and the optocoupler isolation circuit 4, respectively.

[0024] Based on the above structure, the problem of detecting different power supply voltages in incremental encoders can be solved, achieving the purpose of adaptive power supply. The steps are as follows:

[0025] a. After the user system 8 powers on the isolation power supply circuit 5, the isolation power supply circuit 5 generates a 5V power supply for the IC chip, which powers the power supply voltage detection and judgment circuit 1, the control input circuit 2, the differential conversion circuit 3, and the optocoupler isolation circuit 4.

[0026] b. After the encoder power supply 6 powers on the encoder 7, the power supply voltage detection and judgment circuit 1 compares the input power signal with the set comparison voltage, which is set to 2V and 4V, to determine the voltage range of the encoder power supply 6, and then outputs the corresponding control signal to the control input circuit 2. The power supply voltage detection and judgment circuit 1 uses an LM2903 chip.

[0027] Specifically, such as Figure 2As shown, VCC, input from terminal J20, is connected to the anode of diode D9. The cathode of diode D9 is connected to pin 8 of terminal J10. GND, input from pin 2 of terminal J20, is connected to pin 9 of terminal J10, providing power to encoder 7. Simultaneously, VCC is connected to one end of resistors R247 and R267, and capacitor C135. The other end of resistor R247 is connected to resistors R248, R249, R250, and R251, forming a voltage divider circuit. The connection point between resistors R250 and R251 is marked as point A. When the input power signal is 5V, point A outputs 1V; when the input power signal is 15V, point A outputs 3V; and when the input power signal is 24V, point A outputs 4.5V. The other end of resistor R267 is connected to a +5V ISO2 power supply. If resistor R267 is connected, it can provide a 5V backup power supply to encoder 7. The other end of capacitor C135 is connected to GND for power supply filtering. The output at point A is connected to pins 2 and 6 of operational amplifier U33. Pin 5 of operational amplifier U33 is connected to one end of resistors R108 and R109 and capacitor C66, marked as point B. The other end of resistor R108 is connected to the +5V ISO2 power supply, and the other ends of resistor R109 and capacitor C66 are grounded. The set voltage for point B is 2V. Pin 3 of operational amplifier U33 is connected to one end of resistors R103 and R102 and capacitor C65, marked as point C. The other end of resistor R103 is connected to the +5V ISO2 power supply, and the other ends of resistor R102 and capacitor C65 are grounded. The set voltage for point C is 4V. Pin 1 of operational amplifier U33 is connected to pull-up resistor R104 and current-limiting resistor R106. The other end of current-limiting resistor R106 is connected to pin 11 of buffer U34. Operational amplifier U33's pin 7 is connected to pull-up resistor R105 and current-limiting resistor R107. The other end of current-limiting resistor R107 is connected to pin 13 of buffer U34. Buffer U34's pins 15, 17, and 19 are all connected to GND. Buffer U34's output pin 9 is connected to one end of resistor R271. The other end of resistor R271 is connected to resistor R272 and the base of transistor Q47. The other end of resistor R272 and the emitter of transistor Q47 are connected to GND. Buffer U34's output pin 7 is connected to one end of resistor R273. The other end of resistor R273 is connected to resistor R274 and the base of transistor Q48. The other end of resistor R274 and the emitter of transistor Q48 are connected to GND. The collector of transistor Q47 is connected to one end of resistor R115 and... Figure 3 Solid-state relays U21, U17, and U19 are connected to the control input circuit 2. The other end of resistor R115 is connected to the +5V ISO2 power supply. The collector of transistor Q48 is connected to one end of resistor R116 and... Figure 3Solid-state relays U20, U16, and U18 of the control input circuit 2 are connected. The other end of resistor R116 is connected to the +5V ISO2 power supply.

[0028] In the above implementation scheme, if the encoder power supply 6 input is between 0-10V, the control signals output from pins 7 and 1 of operational amplifier U33 are both high; if the input is between 10-20V, pin 7 of operational amplifier U33 outputs a low level, and pin 1 of operational amplifier U33 outputs a high level; if the input is between 20V-25V, pin 7 of operational amplifier U33 outputs a low level, and pin 1 of operational amplifier U33 outputs a low level. Specifically:

[0029] When the encoder power supply is 5V, the voltage at point A is lower than the voltage at point B. Operational amplifier U33's pin 7 outputs a high level, transistor Q48 conducts, and 5VIN_ON outputs a low level. When the voltage at point A is lower than the voltage at point C, operational amplifier U33's pin 1 outputs a high level, transistor Q47 conducts, and 15VIN_ON outputs a low level.

[0030] When the encoder power supply is 15V, the voltage at point A is greater than the voltage at point B. Pin 7 of operational amplifier U33 outputs a low level, transistor Q48 is not conducting, and 5VIN_ON outputs a high level. When the voltage at point A is less than the voltage at point C, pin 1 of operational amplifier U33 outputs a high level, transistor Q47 conducts, and 15VIN_ON outputs a low level.

[0031] When the encoder power supply is 24V, the voltage at point A is greater than the voltage at point B. Therefore, pin 7 of operational amplifier U33 outputs a low level, transistor Q47 is not conducting, and the 5VIN_ON output is high. When the voltage at point A is greater than the voltage at point C, pin 1 of operational amplifier U33 outputs a low level, transistor Q48 is not conducting, and the 15VIN_ON output is high.

[0032] c. The control input circuit 2 controls the single-pole single-throw solid-state relay according to the control signal given by the power supply voltage detection and judgment circuit 1, and adjusts the input matching resistor to realize the adjustment of the encoder signal level; the control input circuit 2 uses CPC1017N solid-state relay, and turns on the downstream load of the solid-state relay according to the input control signal to complete the purpose of adjusting the matching resistor.

[0033] Specifically, such as Figure 3As shown, in the power supply voltage detection and judgment circuit 1, pin 1 of terminal J10 is connected to one end of resistor R252 and pin 4 of solid-state relay U20. The other end of resistor R252 is connected to resistor R253. The other end of R253 is connected to pin 3 of solid-state relay U20, one end of bidirectional Zener diode D10, one end of resistor R254, and then to pin 1 of differential chip U27 in differential conversion circuit 3. Pin 2 of terminal J10 in the power supply voltage detection and judgment circuit 1 is connected to one end of resistor R244 and pin 3 of solid-state relay U21. The other end of resistor R244 is connected to pin 4 of solid-state relay U21, the other end of bidirectional Zener diode D10, the other end of resistor R254, and then to pin 2 of differential chip U27 in differential conversion circuit 3. Pin 1 of solid-state relay U20 is connected to the +5V ISO2 power supply, and pin 2 of solid-state relay U20 is connected to pin 1 of solid-state relay U16. Pin 1 of solid-state relay U21 is connected to the +5V ISO2 power supply, and pin 2 of solid-state relay U21 is connected to pin 1 of solid-state relay U17.

[0034] In the power supply voltage detection and judgment circuit 1, pin 3 of terminal J10 is connected to one end of resistor R238 and pin 4 of solid-state relay U16. The other end of resistor R238 is connected to resistor R239. The other end of R239 is connected to pin 3 of solid-state relay U16, one end of bidirectional Zener diode D7, one end of resistor R240, and then to pin 7 of differential chip U27 in differential conversion circuit 3. Pin 4 of terminal J10 in the power supply voltage detection and judgment circuit 1 is connected to one end of resistor R245 and pin 3 of solid-state relay U17. The other end of resistor R245 is connected to pin 4 of solid-state relay U17, the other end of bidirectional Zener diode D7, the other end of resistor R240, and then to pin 6 of differential chip U27 in differential conversion circuit 3. Pin 1 of solid-state relay U16 is connected to pin 2 of solid-state relay U20, and pin 2 of solid-state relay U16 is connected to pin 1 of solid-state relay U18. Pin 1 of solid-state relay U17 is connected to pin 2 of solid-state relay U21, and pin 2 of solid-state relay U17 is connected to pin 1 of solid-state relay U19.

[0035] In power supply voltage detection and judgment circuit 1, pin 5 of terminal J10 is connected to one end of resistor R241 and pin 4 of solid-state relay U18. The other end of resistor R241 is connected to resistor R242. The other end of resistor R242 is connected to pin 3 of solid-state relay U18, one end of bidirectional Zener diode D8, one end of resistor R243, and then to pin 9 of differential chip U27 in differential conversion circuit 3. In power supply voltage detection and judgment circuit 1, pin 6 of terminal J10 is connected to one end of resistor R246 and pin 3 of solid-state relay U19. The other end of resistor R246 is connected to pin 4 of solid-state relay U19, the other end of bidirectional Zener diode D8, the other end of resistor R243, and then to pin 10 of differential chip U27 in differential conversion circuit 3. Pin 1 of solid-state relay U18 is connected to pin 2 of solid-state relay U16. Pin 2 of solid-state relay U18 is connected to the collector of transistor Q48 in power supply voltage detection and judgment circuit 1. Pin 1 of solid-state relay U19 is connected to pin 2 of solid-state relay U17, and pin 2 of solid-state relay U19 is connected to the collector of transistor Q47 in power supply voltage detection and judgment circuit 1.

[0036] When the encoder power supply is 5V, the 5VIN_ON output is low, solid-state relays U20, U16, and U18 are turned on, and control resistors R252, R253, R238, R239, R241, and R242 are bypassed. The 15VIN_ON output is low. Solid-state relays U21, U17, and U19 are turned on, and control resistors R244, R245, and R246 are bypassed. The voltage difference of the input signal across resistors R254, R240, and R243 is 5V.

[0037] When the encoder power supply is 15V, the 5VIN_ON output is high. Solid-state relays U20, U16, and U18 are not conducting, and resistors R252, R253, R238, R239, R241, and R242 are connected in the circuit, resulting in a low-level 15VIN_ON output. Solid-state relays U21, U17, and U19 are conducting, and control resistors R244, R245, and R246 are bypassed. The input signal voltage difference at resistor R254 is 5V, which is the voltage difference after voltage division by resistors R252, R253, and R254. The voltage difference at resistor R240 is 5V, which is the voltage difference after voltage division by resistors R238, R239, and R240. The voltage difference at resistor R243 is 5V, which is the voltage difference after voltage division by resistors R241, R242, and R243.

[0038] When the encoder power supply is 24V, the 5VIN_ON output is high. Solid-state relays U20, U16, and U18 are not conducting, and resistors R252, R253, R238, R239, R241, and R242 are connected in the circuit, resulting in a high-level 15VIN_ON output. Solid-state relays U21, U17, and U19 are not conducting, and control resistors R244, R245, and R246 are connected in the circuit. The input signal voltage difference at resistor R254 is 6V, which is the voltage difference after voltage division by resistors R252, R253, R254, and R244. The voltage difference at resistor R240 is 6V, which is the voltage difference after voltage division by resistors R238, R239, R240, and R245. The voltage difference at resistor R243 is 6V, which is the voltage difference after voltage division by resistors R241, R242, R243, and R246.

[0039] d. The encoder signals adjusted by the control input circuit 2, A+ and A-, B+ and B-, Z+ and Z- are differential signals. The differential signals are converted by the differential chip U27 of the differential conversion circuit 3. The differential chip U27 is preferably an SN65LBC175 four-channel differential signal receiver.

[0040] e. The differential conversion circuit 3 outputs A, B, and Z phase signals, which are isolated by high-speed optocouplers U35, U38, and U39 in the optocoupler isolation circuit 4. The input and output terminals of the high-speed optocouplers are powered by the power module U36 in the isolation power supply circuit 5. The electrical connection of the two functions is separated, which realizes separation from the user system and enhances the anti-interference capability.

[0041] Specifically, such as Figure 4As shown, pins 1 and 2 of differential chip U27 are connected to resistor R254, pins 7 and 6 are connected to resistor R240, and pins 9 and 10 are connected to resistor R243. Pins 4, 12, 15, and 16 of differential chip U27 are connected to the +5V ISO2 power supply. One end of pin 16 is connected to decoupling capacitor C142, and pin 8 is connected to GND. Output pin 3 of differential chip U27 is connected to pin 2 of buffer U34, output pin 5 is connected to pin 4 of buffer U34, output pin 11 is connected to pin 6 of buffer U34, and pin 13 of differential chip U27 is unconnected. Pins 1, 8, and 10 of buffer U34 are connected to GND. Pin 20 of buffer U34 is connected to the +5V ISO2 power supply, and one end is connected to decoupling capacitor C137. Pin 18 of buffer U34 is connected to one end of resistor R260, and the other end of resistor R260 is connected to pin 3 of high-speed optocoupler U35. Pin 16 of buffer U34 is connected to one end of resistor R255, and the other end of resistor R255 is connected to pin 3 of high-speed optocoupler U38. Pin 14 of buffer U34 is connected to one end of resistor R257, and the other end of resistor R257 is connected to pin 3 of high-speed optocoupler U39. Pins 2 of high-speed optocouplers U35, U38, and U39 are all connected to the +5V ISO2 power supply. Pins 7 and 8 of high-speed optocoupler U35 are connected to the VDD power supply, and pin 6 of high-speed optocoupler U35 is connected to pull-up resistor R261, outputting GS_TB0A_EXT to user system 8. Pins 7 and 8 of high-speed optocoupler U38 are connected to the VDD power supply. Pin 6 of high-speed optocoupler U38 is connected to pull-up resistor R256 and outputs GS_TB1A_EXT to user system 8. Pins 7 and 8 of high-speed optocoupler U39 are connected to the VDD power supply. Pin 6 of high-speed optocoupler U39 is connected to pull-up resistor R258 and outputs GS_TB2A_EXT to user system 8. After the input signal is converted by differential chip U27, when the input at pin 2 of buffer U34 is high, the output at pin 18 is high, high-speed optocoupler U35 is not conducting, and the output at pin 6 is high. When the input at pin 2 of buffer U34 is low, the output at pin 18 is low, high-speed optocoupler U35 is conducting, and the output at pin 6 is low. High-speed optocouplers U35, U38, and U39, along with resistors R260, R255, R257, R261, R256, and R258, together constitute the optocoupler isolation circuit for the three-phase signals A, B, and Z, achieving isolation between the encoder signal and the user system 8.

[0042] like Figure 5As shown, pins 22 and 23 of power module U36 are connected to the VDD power supply of user system 8, capacitor C141, and capacitor E15. Pins 2 and 3 of power module U36, the other end of capacitor C141, and E15 are connected to DGND of user system 8. Pins 9 and 11 of power module U36 are empty. Pin 14 outputs +5VISO2 power and is connected to one end of capacitor E16, capacitor C140, TVS diode D12, and LED D11. Pin 16 of power module U36, the other end of capacitor E16, capacitor C140, and TVS diode D12 are connected to GND. The other end of LED D11 is connected to one end of resistor R259, and the other end of resistor R259 is connected to GND. When the power supply is normal, LED D11 lights up, indicating that the power supply is normal. The +5VISO2 power supply provides power to the power supply voltage detection and judgment circuit 1, control input circuit 2, differential conversion circuit 3, and optocoupler isolation circuit 4.

[0043] Obviously, the above embodiments are merely illustrative examples for clear explanation and are not intended to limit the implementation. Those skilled in the art will recognize that other variations or modifications can be made based on the above description. It is neither necessary nor possible to exhaustively list all possible implementations here. However, obvious variations or modifications derived therefrom are still within the scope of protection of this invention.

Claims

1. An adaptive power supply incremental encoder detection circuit, characterized in that, include: The circuit includes a power supply voltage detection and judgment circuit (1), a control input circuit (2), a differential conversion circuit (3), an optocoupler isolation circuit (4), and an isolated power supply circuit (5). The power supply voltage detection and judgment circuit (1) is connected to the encoder power supply (6) to receive the power signal from the encoder power supply (6). The power supply voltage detection and judgment circuit (1) is also connected to the control input circuit (2) and outputs a control signal to the control input circuit (2). The control input circuit (2) is connected to the output signal terminal of the encoder (7) and the differential conversion circuit (3). The differential conversion circuit (3) is connected to the optocoupler isolation circuit (4). The optocoupler isolation circuit (4) is connected to the user system (8). The user system (8) is connected to the isolated power supply circuit (5). The isolated power supply circuit (5) is connected to the power supply voltage detection and judgment circuit (1), the control input circuit (2), the differential conversion circuit (3), and the optocoupler isolation circuit (4) respectively. After the user system (8) powers on the isolated power supply circuit (5), the isolated power supply circuit (5) generates power supply to power supply voltage detection and judgment circuit (1), control input circuit (2), differential conversion circuit (3), and optocoupler isolation circuit (4); after the encoder power supply (6) powers on the encoder (7), the power supply voltage detection and judgment circuit (1) compares the input power signal with the set comparison voltage. When the input power signals are different, it outputs different control signals to the control input circuit (2). The VCC input from terminal J20 is connected to the anode of diode D9, the cathode of diode D9 is connected to pin 8 of terminal J10, and pin 2 (GND) of terminal J20 is connected to pin 9 of terminal J10. Simultaneously, VCC is connected to one end of resistors R247 and R267, and capacitor C135. The other end of resistor R247 is connected to resistors R248, R249, R250, and R251, forming a voltage divider circuit. The connection point between resistors R250 and R251 is marked as point A. When the input power signal is 5V, point A outputs 1V; when the input power signal is 15V, point A outputs 3V; and when the input power signal is 24V, point A outputs 4.5V. Resistor R2... The other end of 67 is connected to the +5V ISO2 power supply; the other end of capacitor C135 is connected to GND for power supply filtering; the output at point A is connected to pins 2 and 6 of operational amplifier U33. Pin 5 of operational amplifier U33 is connected to one end of resistors R108 and R109 and capacitor C66, marked as point B. The other end of resistor R108 is connected to the +5V ISO2 power supply, and the other ends of resistor R109 and capacitor C66 are grounded; the set voltage at point B is 2V; pin 3 of operational amplifier U33 is connected to one end of resistors R103 and R102 and capacitor C65, marked as point C. The other end of resistor R103 is connected to the +5V ISO2 power supply, and the other ends of resistor R102 and capacitor C65 are grounded. The other end is grounded; the voltage at point C is set to 4V; pin 1 of operational amplifier U33 is connected to pull-up resistor R104 and current-limiting resistor R106, and the other end of current-limiting resistor R106 is connected to pin 11 of buffer U34; pin 7 of operational amplifier U33 is connected to pull-up resistor R105 and current-limiting resistor R107, and the other end of current-limiting resistor R107 is connected to pin 13 of buffer U34; pins 15, 17, and 19 of buffer U34 are all connected to GND; pin 9 of the output terminal of buffer U34 is connected to one end of resistor R271; the other end of resistor R271 is connected to resistor R272 and the base of transistor Q47; the other end of resistor R272 and the emitter of transistor Q47 are connected to GND. The output pin 7 of buffer U34 is connected to one end of resistor R273. The other end of resistor R273 is connected to resistor R274 and the base of transistor Q48. The other end of resistor R274 and the emitter of transistor Q48 are connected to GND. The collector of transistor Q47 is connected to one end of resistor R115 and to solid-state relays U21, U17, and U19 of control input circuit (2). The other end of resistor R115 is connected to +5V ISO2 power supply. The collector of transistor Q48 is connected to one end of resistor R116 and to solid-state relays U20, U16, and U18 of control input circuit (2). The other end of resistor R116 is connected to +5V ISO2 power supply. The control input circuit (2) adjusts the signal level of the encoder (7) according to the input control signal. The adjusted encoder (7) signal is transmitted to the differential conversion circuit (3) for signal conversion. The converted signal is isolated by the optocoupler isolation circuit (4) and then connected to the user system (8). The control input circuit (2) controls the solid-state relay according to the input control signal, turns on the load after the solid-state relay, adjusts the input matching resistor, and realizes the adjustment of the encoder (7) signal level; The differential conversion circuit (3) converts the encoder (7) signal through four differential signal receivers; The differential conversion circuit (3) outputs A, B, and Z phase signals, which are isolated by the high-speed optocoupler of the optocoupler isolation circuit (4).

2. The adaptive power incremental encoder detection circuit according to claim 1, characterized in that, The comparison voltages are set to 2V and 4V.

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