72V single-phase linear servo amplifier system

Abstract

The invention discloses a single-channel 72V single-phase linear servo amplifier system. The invention relates to the technical field of PWM servo control. The input voltage is converted into the 72V voltage grade required by the circuit so as to meet the driving requirement of the motor; the LP-39 and the GND serve as power supplies and are connected with the ground, so that the circuit is ensured to obtain stable power supply; through the filtering design of the power supply module, the differential signal-to-single-ended signal circuit and the filtering measure in the summing circuit, noise and current ripples in the circuit are remarkably reduced, and thus the signal quality is improved. The noise and the current ripples are reduced, interference and misoperation in the circuit are reduced, and the stability and the reliability of the whole servo system are enhanced. Meanwhile, the driver is free of software logic, pure hardware design is achieved, the development period is shortened, and the development cost is reduced. The linear driver is simple in structure, high in output power, small in size and dual in channel, and can perfectly replace TA115, SMA5005 and other foreign commercial linear drivers.

Description

Technical Field

[0001] The present invention relates to the technical field of PWM servo control, specifically to the technical field of linear servo amplifiers, and particularly to a 72V single-phase linear servo amplifier system. Background Art

[0002] In the domestic market, traditional PWM (Pulse Width Modulation) servo technology has been relatively mature, and many well-known brands such as Inovance, Hechuan, and Leadshine have emerged. However, with the continuous improvement of the accuracy requirements of semiconductor equipment, the limitations of PWM servo technology have become increasingly prominent.

[0003] Although PWM servo technology has shown good stability and reliability in practical applications, its inherent noise problem and the defect of relatively large current ripple make it unable to meet the stringent requirements for control accuracy of high-precision semiconductor equipment. Especially in the static state, the jitter phenomenon existing in the PWM servo system poses a potential threat to the equipment performance and product quality.

[0004] To overcome these defects of PWM servo technology, linear servo amplifiers have emerged as a new solution. Linear servo amplifiers have significant advantages such as zero switching noise and extremely small ripple current, which can significantly improve the control accuracy and stability of the servo system. Therefore, with the help of linear servo amplifiers, semiconductor equipment is expected to achieve higher-precision control, thereby meeting the growing process requirements.

[0005] However, in the existing technology, whether it is AC (alternating current) servo or DC (direct current) servo, the mainstream products in the domestic market still adopt the PWM technology form, which limits the improvement of the servo system performance. At the same time, although commercial linear amplifiers such as TURSTTA115 solve the problems of PWM servo to a certain extent, their output power is relatively low and cannot meet the needs of high-power motors. While the SMA5005 of GLENTEK has a relatively large power, its volume is also relatively large and the cost is high, which becomes a restricting factor in application scenarios with limited space.

[0006] In summary, the main technical problems faced by the current servo technology include: (1) The noise and current ripple problems of PWM servo technology: Due to the existence of switching actions, the PWM servo system inevitably generates noise and current ripple, which affects the control accuracy and stability of the system.

[0007] (2) The requirements of high-power motors for the output power of linear amplifiers: The output power of existing commercial linear amplifiers often cannot meet the needs of high-power motors, restricting their application in high-performance servo systems.

[0008] Therefore, developing a linear servo amplifier with high output power and customizable small size has become the key to solving the current servo technology problems. Such an amplifier can not only meet the needs of high-power motors, but also achieve flexible layout in application scenarios with limited space, thereby improving the overall performance and reliability of the servo system.

[0009] To this end, the present invention proposes a 72V single-phase linear servo amplifier system. Summary of the invention

[0010] In view of this, the embodiment of the present invention hopes to provide a 72V single-phase linear servo amplifier system to solve or alleviate the technical problems existing in the prior art, namely, the noise and current ripple problems of PWM servo technology, the requirements of high-power motors for linear amplifier output power, and the contradiction between single-channel output and spatial layout, and at least provide a beneficial option for this; the technical solution of the present invention is implemented as follows: 72V single phase linear servo amplifier system, including: Power module: converts the input voltage to the 72V voltage level required by the circuit to meet the driving requirements of the motor; GND is used as the power and ground connection to ensure that the circuit obtains a stable power supply; Signal input: including the voltage source 36V2 of the input signal and the input signal port IN; these components are responsible for receiving external input signals and providing raw data for subsequent signal processing; Signal processing module: It includes the first op amp for preliminary amplification, the second op amp for further amplification, and the third op amp for filtering and shaping. These op amps are connected through a network of resistors and capacitors to form a complex signal processing path.

[0011] Temperature alarm module: includes temperature sensor; the temperature sensor monitors the temperature of the circuit in real time. Once the temperature is too high, it will trigger the alarm mechanism to ensure the safe operation of the circuit. This is an important measure to protect the circuit from overheating damage.

[0012] Output: including Word A output port and Word B output port responsible for outputting processed signals to external devices or systems to realize the interaction between the circuit and the external environment; Preferably, the system should be powered by dual 36V power supplies, with ±36V used to power the power amplifier. The ideal maximum output voltage difference between MotorA and MotorB can reach 72V.

[0013] It can be understood that the above mode is essentially the op amp as a voltage-controlled constant current source. ±10V differential signal analog input. Enable signal input, temperature acquisition and power supply detection alarm.

[0014] The control mode selection port is used to select different operation modes.

[0015] In one embodiment: The power supply module includes: Power supply terminal JP1 with dual power supply: The circuit can obtain power from two different power supplies to improve the reliability and stability of the system; Dual fuses F1 and F2, with specifications of 65V, 20A, are respectively connected in series on the two power input lines; They can melt the fuses in time when overcurrent or short circuit occurs in the circuit to protect the circuit from damage.

[0016] Soft start circuit composed of JK2, R106 and R107; Its main function is to prevent the inrush current when powering on from burning out the fuse. When the power is just turned on, the soft start circuit limits the magnitude of the current through resistors R106 and R107, gradually raises the voltage of the power supply, and avoids the impact of instantaneous large current on the circuit; As the voltage rises, both JK2 relay and JK1 are enabled to control closing; Six 3300uF / 50V filter capacitors connected in parallel on the power line to smooth the power supply voltage, filter out high-frequency noise and fluctuations in the power supply, and ensure the stable operation of the circuit; The rear-end relay JK1 is used to cut off or connect the power supply of the power; By controlling the on / off of JK1, the enable control of the driver can be realized, that is, when it is necessary to stop the driver from working, the power supply of the power can be disconnected by cutting off JK1.

[0017] In one embodiment: The power supply module further includes: Enable control circuit composed of Q5, Q4, U19, Q6, which is used to control the enable signal of the driver. When the temperature sensor detects that the temperature of the radiator exceeds 78.5°C, the over-temperature self-locking circuit will be triggered, and the output of the driver will be turned off by controlling relevant components to protect the circuit from overheat damage; D6 and D11 are relay freewheeling diodes connected in parallel at both ends of relays JK1 and JK2; They are used to prevent the inductive voltage generated when the relay switches from damaging the components.

[0018] U15 is a URA4812S_10WR3 dual-channel power supply module, which provides stable power for components such as relays and operational amplifiers; U17 is a WRB2405S-3WR2 single-channel 5V power supply module, which provides the required power for the digital circuit; Three reserved groups of 102 / 1KV, 1MΩ resistor-capacitor components are used for grounding treatment.

[0019] In one embodiment: The temperature alarm module includes: The input terminal of the reset chip U1 is connected to the digital power supply voltage, and the output terminal is connected to the AND gate U3; U1 is responsible for monitoring the stability of the digital power supply voltage. When the power supply voltage fluctuates beyond the normal range, U1 will output a low-level signal. This signal will be recognized by the subsequent circuit (such as the AND gate U3), and then trigger the alarm mechanism.

[0020] U8 is a temperature acquisition chip. The matching resistor R27 can control the signal level of pin 7 of the chip, and the matching resistor R29 can control the signal level of pin 6.

[0021] Exemplarily, when the temperature exceeds 65°C, pin 7 drives Q2 to report an error externally. When the temperature exceeds 78.5°C, pin 6 triggers the shutdown of the driver enable control for self-locking protection.

[0022] The input terminals of the AND gate circuit U3 receive signals from the reset chip U1 and the temperature sensing chip U8, and the output terminal is connected to the drivers Q1 and U4; As an AND gate circuit, U3 will only output a high-level signal when all its input terminals receive high-level signals. In this circuit, only when U1 detects that the power supply voltage is stable and U8 detects that the temperature does not exceed the set value, U3 will not output an error signal. Once any one of U1 or U8 outputs a low-level signal, U3 will output a high-level signal to trigger the alarm.

[0023] The input terminals of the drivers Q1 and U4 are connected to the output terminal of the AND gate U3, and the output terminals are connected to the indicator light, relay or buzzer; As drivers, Q1 and U4 are responsible for converting the error signal output by the AND gate U3 into a visual error state. When U3 outputs a low level to trigger the alarm, Q1 and U4 will be activated to drive the alarm device to work, reminding the user to pay attention to the abnormal situation.

[0024] The input terminal of the enable optocoupler U11 receives a signal from the controller, and the output terminal is connected to the digital power supply; As an optocoupler, U11 is used to isolate and control the enable state of the digital power supply. By controlling the input signal of U11, the operation of turning on or off the digital power supply can be realized. This helps to safely cut off the power supply when there is a fault in the circuit or maintenance is required.

[0025] The input terminal of the DIP switch SW1 is connected to the output terminal of the controller or the enable optocoupler U11. As an interface for user settings, SW1 allows the user to adjust the enable state of the digital power supply and set the volt-ampere ratio of the driver as needed. By toggling the different positions of SW1, the user can achieve flexible control of the circuit to meet different application requirements.

[0026] Among them, in one implementation: The differential signal to single-ended signal circuit includes: The differential signals SIG2+ and SIG2- are used as input signals and are respectively connected to the input terminal 1 and input terminal 2 of the high-voltage differential operational amplifier U26 through the resistor R96 (10KΩ); the main function of the resistor R96 is to limit the current of the input signal, thereby protecting the input terminal of U26 from being impacted by excessive current.

[0027] The circuit is powered by dual power supplies, +12V and -12V respectively. After the +12V power supply is filtered by the capacitor C86 (100nF), on the one hand, it is directly connected to the input terminal 3 of U26, and on the other hand, it is connected to the input terminal 6 of U26 through the resistor R94 (100Ω); the resistor R94 also plays a role in limiting current and protecting the circuit. The -12V power supply is filtered by the capacitor C92 (100nF) and then connected to the input terminal 4 of U26 to provide a negative voltage for U26; The capacitors C86 and C92 are respectively connected between the +12V and -12V power supplies and the input terminals of U26. Their main function is to filter out the high-frequency noise in the power supply to ensure that the input terminals of U26 can receive a stable and clean power supply voltage; the capacitor C90 is connected between the output terminal Ui of U26 and the ground to filter out the high-frequency noise in the output signal and ensure the stability and accuracy of the output signal; The output terminal (output terminal 7) of U26 outputs the single-ended signal Ui; Ui is the single-ended representation of the differential signals SIG2+ and SIG2- amplified by U26 and is used for the subsequent linear servo amplifier circuit.

[0028] All the ground wires (GND) in the circuit are connected together to form the common reference point of the circuit. This ensures that all parts of the circuit can work based on the same potential reference, thereby guaranteeing the stability and accuracy of the circuit.

[0029] In one implementation: In the addition circuit: The operational amplifier U25 is responsible for performing the addition operation. Its inverting input terminal ("-" or pin 2) receives the superimposed signal of the external signal Ui and the sampling signal Uf; the non-inverting input terminal (marked as "+" or pin 3) is indirectly connected to the power supply +12V through the capacitor C84, which is used to provide a stable reference potential or perform power supply decoupling. The output terminal ("Out" or pin 6) outputs the added signal Uo; the resistor R95 is connected between the sampling signal Uf and the inverting input terminal of the operational amplifier to introduce the Uf signal into the addition operation; these three resistors jointly determine the voltage division ratio of the input signal; the resistor R92 is connected between GND and the inverting input terminal of the operational amplifier, which plays a role in current limiting and providing a stable reference voltage; the resistor R93 is connected between the external signal Ui and the inverting input terminal of the operational amplifier to introduce the Ui signal into the addition operation; R89 is a potentiometer used for gain calibration of the operational amplifier, that is, for offset adjustment; C84 and C88 are source filtering capacitors of the operational amplifier, and the amplification factor is: Uo = (Uf + Ui) * 5.5; Capacitor C81, resistors R3, R85, and R88 form an RC filter circuit for filtering out high-frequency noise in the input signal; when R88 is 0K, C81 mainly functions as a decoupling capacitor to prevent power supply noise from affecting the circuit; capacitor C84 is connected between +12V and the non-inverting input terminal of the operational amplifier for further decoupling or providing a stable reference potential; capacitor C88 is connected between the output terminal of the operational amplifier and GND as an output filtering capacitor to ensure the stability and accuracy of the output signal Uo; the combination of resistors R3, R85, and R88 forms a voltage division network in the circuit; External signal Ui and sampling signal Uf enter the inverting input terminal of the operational amplifier through resistors R93 and R95 respectively. The operational amplifier performs operations based on the superimposed signal at the inverting input terminal and the feedback network, making the output Uo the superimposed result of Ui and Uf. Capacitors C81, C84, and C88 are used for input signal decoupling, providing a stable reference potential, and output signal filtering respectively to ensure the stability and accuracy of the circuit.

[0030] Furthermore, the non-inverting input terminal of the operational amplifier is connected to Uf and Ui, and the amplification gain is controlled by resistors R3, R85, and R92; C81 and R88 are connected in series for filtering and waveform shaping; R89 is a potentiometer used for gain calibration of the operational amplifier, that is, for offset adjustment; C84 and C88 are source filtering capacitors of the operational amplifier, and the amplification factor is: Uo = (Uf + Ui) * 5.5 In one implementation: in the power output non-inverting amplifier circuit: the circuit includes filtering capacitors (C73, C76, C82, C83, C85, C87, and C89) and a power supply capacitor (C67) which are connected in parallel on the power supply line for filtering out power supply noise to ensure the stable operation of the amplifier; power supplies +Vs and -Vs are connected to the corresponding power supply lines through resistors R86 and directly respectively to provide the required power supply voltage for the operational amplifier.

[0031] The input signal first enters the non-inverting input terminal (pin 1) of the core operational amplifier U23 (OPA541) of the first amplification channel through the input resistor R77, and at the same time, another input signal enters the non-inverting input terminal of the core operational amplifier U24 of the second amplification channel through the input resistor R87; U23 is a first-stage non-inverting power amplifier, and the amplification gain is determined by resistors R81 and R77, and the amplification factor is 4 times; the feedback resistor R80 is connected in series with C73 for filtering, and both 10uF / 100V and 100nf / 100V are source filtering capacitors; similarly, the feedback resistor R90 is connected to the inverting input terminal of U24 to also form negative feedback; R82 and R91 are 0.1R power amplifier current-limiting resistors for overcurrent protection; The amplified signal is output from the output terminal of U23 through the output resistor R81 to form the output signal Uo of the first channel; the operational amplifier U24 acts as a follower amplifier, and R86, R87, and C67 are used to improve the circuit stability. The series connection of R90 and C85 is used for filtering to improve stability.

[0032] Since the input signal enters the operational amplifier through the non-inverting input terminal and the feedback resistor is connected to the inverting input terminal, the circuit realizes non-inverting amplification.

[0033] It can be understood that the voltage direction of the output signal Uo is the same as that of the input signal. The gain of the operational amplifier is determined by the ratio of the input resistor and the feedback resistor, that is, the gain A = Rf / Ri, where Rf is the feedback resistor and Ri is the input resistor. In this circuit, the gain is determined by R80 / R77 and R90 / R87. The output terminal of U24 is connected to the output terminal of U23 to form a series amplification path. In this way, U24 can further amplify the output signal of U23, thereby enhancing the output current of the entire circuit.

[0034] In one implementation: in the power output inverting amplifier circuit: Uo, as the output signal of the summing operational amplifier, passes through the filter circuit composed of the resistor R97 (40K) and the capacitor C91 (220PF). This combination effectively filters out high-frequency noise and ensures the purity of the signal entering the subsequent circuit; The filtered signal enters the first-stage inverting amplifier U27, and the amplification gain is determined by the resistors R99 and R97. The principle is the same as that described above and will not be elaborated here; that is, the direction of the output signal is opposite to that of the input signal Uo, realizing a 180-degree inversion. The resistor R98 (100K) and the capacitor C93 (10uF / 100V) optimize the signal amplification effect in the inverting amplifier circuit, ensuring the stability and accuracy of the signal. At the same time, the capacitor C94 (100nF / 100V) further filters out the high-frequency noise in the signal and improves the signal purity.

[0035] Exemplarily, the driver amplification logic: for example: after the adder, the signal Uo is 2V, the non-inverting amplifier output Ua is 8V, and Ub is -8V, then the voltage difference of 16V between Ua and Ub is provided to drive the motor. The signal after inverting amplification enters the subsequent circuit, where the connection method of the resistor R100 (0.1R) and the capacitor C96 helps to increase the output current; the power amplifier U28 is used to further increase the output current to ensure the stable operation of the B phase of the motor; the output signal Ub is connected to the B phase of the motor through an anti-parallel freewheeling diode. The role of the anti-parallel freewheeling diode is to prevent problems such as motor reversal caused by signal inverting amplification and ensure the stable operation of the B phase of the motor.

[0036] In one embodiment: In the current sampling circuit: The in-phase amplified output Ua is connected to one end of the sampling resistor R84; The sampling resistor R84 is a precision low-resistance resistor, which is used to convert the current of the A-phase of the motor into a voltage signal. When the current flows through R84, a voltage drop proportional to the current will be generated across its two ends. The other end of the sampling resistor R84 is connected to the positive electrode of the anti-freewheeling diode; The function of the anti-freewheeling diode is to prevent the back electromotive force generated when the motor is powered off from damaging the circuit. When the motor current suddenly interrupts, the diode will conduct, providing a bypass for the current, thereby protecting other components in the circuit. The negative electrode of the anti-freewheeling diode is connected to the A-phase of the motor; In this way, the current can flow from the in-phase amplified output Ua through the sampling resistor R84 and the anti-freewheeling diode, and finally reach the A-phase of the motor. The differential operational amplifier U22 is used to convert the voltage difference (i.e., the current signal) across the sampling resistor R84 into a single-ended signal; The reverse input terminal of U22 is connected to the left side of R84, the high end; The output terminal is connected to the non-inverting input terminal of U21; The output terminal of U21 is Uf, which is connected to the non-inverting adder. R75 is a potentiometer for adjusting the bias and calibrating the amplification gain. R71 and C70 are reserved for resistor-capacitor filtering and can be ignored; The amplification gain is determined by the resistors R76 and R70, R72, R73, R74. The analog switch U20 controls the channel switching through DTS2_D0 and DTS2_D1. R70, R72, R73, R74 respectively correspond to the current control of 8A, 6A, 4A, 2A, that is, the volt-ampere ratio configuration of the amplifier.

[0037] Aiming at the problems of the traditional technology, the solution of the present invention lies in: (1) Solving the problems of noise and current ripple in PWM servo technology: The circuit uses 6 parallel 3300uF / 50V filter capacitors, which can effectively smooth the power supply voltage and filter out the high-frequency noise and fluctuations in the power supply. In addition, filter capacitors (such as C86, C92, etc.) are also used at each power input terminal to further ensure the stable operation of the circuit and reduce the noise and ripple caused by the power supply. Through the high-voltage differential operational amplifier U26, the differential signals SIG2+ and SIG2- are converted into a single-ended signal Ui. The differential signal itself has a certain anti-noise ability. After being converted into a single-ended signal, through the subsequent filtering and amplification circuits, the influence of noise and ripple can be further reduced. In the adder circuit, a filter circuit is formed by components such as capacitors C81, C84, and C88 to filter out the high-frequency noise in the input signal, ensure the accuracy of the addition operation, and at the same time reduce the noise and ripple in the output signal.

[0038] (2) Meeting the requirements of high-power motors for the output power of linear amplifiers: Two core operational amplifiers U23 and U24 are used for non-inverting amplification, and their output terminals are connected in the circuit to form a series amplification path to increase the output current. This design can significantly improve the output power of the amplifier and meet the requirements of high-power motors. In the inverting amplification circuit, the signal is inverted by the power operational amplifier U27, and the output current is further increased by the subsequent power amplifier U28. This inverting amplification design, combined with the use of power amplifiers, can ensure the stable operation of phase B of the motor while providing sufficient output power.

[0039] Compared with the prior art, the beneficial effects of the present invention are as follows: I. Effective reduction of noise and current ripple: Through the filtering design of the power supply module, the differential signal to single-ended signal circuit, and the filtering measures in the addition circuit, the present invention significantly reduces the noise and current ripple in the circuit, thereby improving the signal quality. Reducing noise and current ripple helps to reduce interference and malfunction in the circuit and enhance the stability and reliability of the entire servo system. At the same time, the driver has no software logic and is a pure hardware design, reducing the development cycle and development cost. It has high output power, small size, and dual channels, and can perfectly replace foreign commercial linear drivers such as TA115 and SMA5005.

[0040] II. Significant improvement in output power: The design of the power output non-inverting amplification circuit and the power output inverting amplification circuit enables the present invention to output higher power and meet the driving requirements of high-power motors. By providing a stable and high-power output signal, the present invention helps to achieve precise control of the motor and improve the operating efficiency and performance of the motor.

[0041] III. Improvement in overheat protection and safety performance: The temperature alarm module can monitor the temperature of the circuit in real time and trigger an alarm mechanism when the temperature is too high, thereby protecting the circuit from overheat damage. The enable control circuit can safely cut off the power supply when a fault occurs in the circuit or maintenance is required, ensuring the safe operation of the circuit. BRIEF DESCRIPTION OF THE DRAWINGS

[0042] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the following will briefly introduce the drawings required for use in the description of the embodiments or the prior art. Obviously, the drawings in the following description are only some embodiments of the present application. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts.

[0043] Figure 1 It is a schematic diagram of the single-channel topology of the present invention; Figure 2 It is a schematic diagram of the power supply circuit of the present invention; Figure 3 Schematic diagram of the alarm circuit of the present invention; Figure 4 Schematic diagram of the differential signal to single-ended signal circuit (analog circuit) of the present invention; Figure 5 Schematic diagram of the addition circuit (analog circuit) of the present invention; Figure 6 Schematic diagram of the in-phase power output amplification circuit of the present invention; Figure 7 Schematic diagram of the reverse power output amplification circuit of the present invention; Figure 8 Schematic diagram of the current sampling circuit of the present invention. Detailed implementation manners

[0044] To make the above objects, features and advantages of the present invention more obvious and understandable, the following will describe the detailed implementation manners of the present invention with reference to the accompanying drawings. Many specific details are set forth in the following description in order to fully understand the present invention. However, the present invention can be implemented in many other ways different from those described herein, and those skilled in the art can make similar improvements without departing from the connotation of the present invention. Therefore, the present invention is not limited by the specific embodiments disclosed below; Embodiment 1: In the prior art, due to the existence of switching actions, the PWM servo system will inevitably generate noise and current ripple, which affects the control accuracy and stability of the system. The output power of existing commercial linear amplifiers often cannot meet the requirements of high-power motors, restricting their application in high-performance servo systems. Although some linear amplifiers have excellent performance, they are relatively large in size and only have single-channel output, which causes difficulties in layout in application scenarios with limited space. For this reason, this embodiment provides a 72V single-phase linear servo amplifier system, the structure of which is as Figure 1 shown, specifically including: (1) Power supply module (corresponding to the attached Figure 2 ): This module is responsible for converting the input voltage into the 72V voltage level required by the circuit. Among them, the power supply terminal JP1 with dual power supply ensures that the circuit can obtain power from two different power supplies, improving the reliability and stability of the system. The two fuses F1 and F2 are connected in series on the two power input lines to fuse in time when overcurrent or short circuit occurs in the circuit to protect the circuit. The soft start circuit is composed of JK2, R106 and R107 to prevent the inrush current when powering on from burning out the fuse. Six parallel 3300uF / 50V filter capacitors smooth the power supply voltage and filter out high-frequency noise. The rear-end relay JK1 is used to cut off or connect the power supply to realize the enable control of the driver.

[0045] (2) Signal input module: It includes the voltage source 36V2 of the input signal and the input signal port IN, and is responsible for receiving external input signals.

[0046] (3)Signal processing module: This module contains three operational amplifiers, which are respectively used for preliminary amplification, further amplification, filtering and shaping to form a complex signal processing path.

[0047] (4)Temperature alarm module (corresponding to the appendix Figure 3 ): It includes components such as a temperature sensor, a reset chip U1, a dual-channel temperature sensing chip U8, and a NAND gate circuit U3. The temperature sensor monitors the circuit temperature in real time. Once the temperature is too high, it protects the circuit by triggering an alarm mechanism. The reset chip U1 monitors the stability of the digital power supply voltage. The NAND gate circuit U3 controls the output states of the drivers Q1 and U4 according to the signals of the reset chip U1 and the temperature sensing chip U8, thereby driving the alarm device to work.

[0048] (5)Output module: It includes output ports MotorA and Motorb, which are responsible for outputting the processed signals to external devices.

[0049] Through the above structure, this embodiment realizes functions such as stable power supply, signal processing, temperature monitoring and alarm of the servo amplifier circuit. Embodiment 2: On the basis of Embodiment 1, this embodiment further details the specific implementation methods of the differential signal to single-ended signal circuit (corresponding to the appendix Figure 4 )and the addition circuit (corresponding to the appendix Figure 5 ): (1)Differential signal to single-ended signal circuit: The differential signals SIG2+ and SIG2- are connected to the input terminals of the high-voltage differential operational amplifier U26 through the resistor R96, and the resistor R96 limits the input signal current. It is powered by +12V and -12V dual power supplies, which are respectively connected to the corresponding input terminals of U26 after being filtered by the capacitors C86 and C92. The capacitor C90 is connected between the output terminal Ui of U26 and the ground to filter out high-frequency noise in the output signal. U26 outputs a single-ended signal Ui for the subsequent linear servo amplifier circuit.

[0050] (2)Addition circuit: The operational amplifier U25 performs an addition operation, and its inverting input terminal receives the superimposed signal of the external signal Ui and the sampling signal Uf. The capacitors C81, C84 and C88 are respectively used for input signal decoupling, providing a stable reference potential and output signal filtering. The resistors R92, R93 and R95 jointly determine the voltage division ratio of the input signals. The output terminal outputs the added signal Uo.

[0051] Through the design of the differential signal to single-ended signal circuit and the addition circuit, this embodiment further improves the accuracy and stability of signal processing, and provides a reliable signal source for power amplification in subsequent embodiments. Embodiment 3: Based on Embodiment 2, this embodiment details the specific implementation methods of the power output in-phase amplification circuit (corresponding to Appendix Figure 6 ), the power output reverse amplification circuit (corresponding to Appendix Figure 7 ), and the current sampling circuit (corresponding to Appendix Figure 8 ), and adopts a progressive protection layout: (1) Power output in-phase amplification circuit: The input resistors R83 and R86 enter the non-inverting input terminals of operational amplifiers U23 and U24, and R77 is the negative feedback resistor. R82 and R91 are output current protection resistors.

[0052] (2) Power output reverse amplification circuit: The output signal Uo of the summing operational amplifier is filtered and then enters the power operational amplifier U27 for reverse amplification. The resistors R98 and capacitor C93 optimize the signal amplification effect. The signal after reverse amplification further increases the output current through the resistors R100 and R105 in the subsequent circuit, and the power amplifier U28 ensures the stable operation of the B-phase of the motor. U28 is a follower, and the non-inverting input terminal is connected to the output terminal of U27 through R102 to increase the current output (3) Current sampling circuit: The in-phase amplified output Ua is connected to one end of the sampling resistor R84 to convert the current of the A-phase of the motor into a voltage signal. The differential operational amplifier U22 converts the voltage difference across the sampling resistor R84 into a single-ended signal, and the non-inverting operational amplifier U21 amplifies this single-ended signal. The analog switch U20 selects different amplification factors according to external configurations to configure the volt-ampere ratio.

[0053] The temperature alarm module monitors the circuit temperature in real time and triggers an alarm once the temperature is too high; the enable control circuit cuts off the power supply in case of a circuit fault; the sampling resistor R84 and the anti-parallel freewheeling diode prevent the reverse electromotive force generated when the motor is powered off from damaging the circuit. In addition, through reasonable circuit layout and component selection, the anti-interference ability and stability of the circuit are improved. Embodiment 4: As Figure 4 shown, the differential signals SIG2+ and SIG2- are used as inputs and are connected to the input terminal of the high-voltage differential operational amplifier U26 through the precision resistor R96 (10KΩ). This resistor not only limits the input current to protect the operational amplifier but also ensures the stability of signal transmission. The circuit is powered by a ±12V dual power supply and is filtered by capacitors C86 and C92 to eliminate the high-frequency noise in the power supply and provide a pure power supply voltage for U26. The output terminal Ui of U26 generates a single-ended representation of the differential signal, and this signal is further filtered by capacitor C90 to eliminate the high-frequency noise in the output and ensure the stability and accuracy of the signal. The core of this circuit principle lies in using the characteristics of the differential operational amplifier to effectively convert the differential signal into a single-ended signal and provide a high-quality signal input for the subsequent circuit. Embodiment 5, as Figure 5As shown, the core of the adder circuit is the operational amplifier U25, whose inverting input terminal receives the superimposed signal of the external signal Ui and the sampling signal Uf. Resistors R92, R93, and R95 form a voltage division network to precisely control the voltage division ratio of the input signal. Capacitors C81, C84, and C88 are respectively used for input signal decoupling, providing a stable reference potential, and output signal filtering to ensure the stability and accuracy of the circuit. The realization of the addition operation depends on the virtual short and virtual open characteristics of the operational amplifier, making the output signal Uo the superimposed result of Ui and Uf. The key to this circuit principle lies in achieving accurate addition operation of signals through precise voltage division network and filtering design, providing an accurate input signal for subsequent power amplification. Embodiment Six: As Figure 6 shown, it is composed of two core operational amplifiers U23 and U24, forming two amplification channels respectively. And the output terminal of U24 is connected to the output terminal of U23 to form a series amplification path to increase the output current. The core of this circuit principle lies in utilizing the non-inverting amplification characteristics of the operational amplifier to achieve precise signal amplification and increasing the output current through the series amplification path to meet the driving requirements of high-power motors. Embodiment Seven: The current sampling circuit is as Figure 8 shown. The current of phase A of the motor is converted into a voltage signal through the sampling resistor R84, and the differential operational amplifier U22 converts the voltage difference across the sampling resistor into a single-ended signal. The non-inverting operational amplifier U21 further amplifies this single-ended signal, and the analog switch U20 selects different amplification multiples according to external configuration to configure the volt-ampere ratio. The anti-parallel freewheeling diode prevents the reverse electromotive force generated when the motor is powered off from damaging the circuit. The core of this circuit principle lies in utilizing the characteristics of the sampling resistor and the differential operational amplifier to precisely measure the motor current, and through the amplification and configuration of the subsequent circuit, achieving precise control and monitoring of the motor current.

[0054] The above embodiments only represent the implementation manners of the relevant practical applications of the present invention. The description is relatively specific and detailed, but it should not be construed as a limitation on the scope of the invention patent. It should be noted that for those of ordinary skill in the art, without departing from the concept of the present invention, several modifications and improvements can still be made, and these all belong to the protection scope of the present invention. Therefore, the protection scope of the present invention patent shall be subject to the appended claims.

Claims

1. Dual-channel 72V single-phase linear servo amplifier system, characterized in that, include: Power module: converts the input voltage to the 72V voltage level required by the circuit; Signal input: including the voltage source 36V2 of the input signal and the input signal port IN; Signal processing module: includes the first operational amplifier for preliminary amplification, the second operational amplifier for further amplification, and the third operational amplifier for filtering and shaping; Temperature alarm module: including temperature sensor; Output: includes Word A output port and Word B output port, which are responsible for outputting the processed signal to external devices or systems to realize the interaction between the circuit and the external environment.

2. The amplifier system according to claim 1, characterized in that: The power module comprises: Power terminal JP1 for dual power supply; The double fuses F1 and F2 are connected in series to the two power input lines respectively; The soft start circuit is composed of JK2, R106 and R107; as the voltage increases, the JK2 relay gradually closes, allowing the circuit to enter a normal working state; 6 3300uF / 50V filter capacitors connected in parallel on the power line; The rear relay JK1 is used to cut off or connect the power supply.

3. The amplifier system according to claim 2, characterized in that: The power module also includes: The enable control circuit composed of Q5, Q4, U19 and Q6 is used to control the enable signal of the driver; D6 and D11 are relay freewheeling diodes connected in parallel at both ends of the coil of relay JK1; U15 is a URA4812S_10WR3 dual-channel power module; U17 is a WRB2405S-3WR2 single-channel 5V power module; The three sets of 102 / 1KV, 1MΩ resistors and capacitors are reserved for grounding.

4. The amplifier system according to claim 1, characterized in that: The temperature alarm module comprises: The input end of the reset chip U1 is connected to the digital power supply voltage, and the output end is connected to the AND gate U3; The input end of the dual-channel temperature sensor chip U8 is connected to the external environment through a thermistor, and the output end is connected to matching resistors R27, R29 and an AND gate U3; The input end of the AND gate circuit U3 receives signals from the reset chip U1 and the temperature sensor chip U8, and the output end is connected to the drivers Q1 and U4; The input terminals of drivers Q1 and U4 are connected to the output terminal of AND gate U3, and the output terminal is connected to an indicator light, relay or buzzer; The input end of the enable optocoupler U11 receives the signal from the controller, and the output end is connected to the digital power supply; The input end of the dip switch SW1 is connected to the output end of the controller or the enable optical coupler U11.

5. The amplifier system according to claim 1, characterized in that: The differential signal to single-ended signal circuit includes: The differential signals SIG2+ and SIG2- are used as input signals and are connected to the input terminals 1 and 2 of the high-voltage differential operational amplifier U26 through the resistor R96 respectively; The circuit is powered by dual power supplies, +12V and -12V respectively. The +12V power supply is filtered by capacitor C86 and directly connected to input terminal 3 of U26 on one hand, and connected to input terminal 6 of U26 through resistor R94 on the other hand; the -12V power supply is filtered by capacitor C92 and connected to input terminal 4 of U26 to provide negative voltage for U26; Capacitors C86 and C92 are connected between the +12V and -12V power supplies and the input terminal of U26 respectively; capacitor C90 is connected between the output terminal Ui of U26 and the ground to filter out high-frequency noise in the output signal; The output end of U26 outputs a single-ended signal Ui.

6. The amplifier system according to claim 5, characterized in that: In the adding circuit: Operational amplifier U25 is responsible for performing addition operations, and its inverting input terminal receives the superposition signal of the external signal Ui and the sampling signal Uf; its non-inverting input terminal is indirectly connected to the power supply +12V through capacitor C84; Resistor R92 is connected between GND and the inverting input terminal of the operational amplifier; resistor R93 is connected between the external signal Ui and the inverting input terminal of the operational amplifier to introduce the Ui signal into the addition operation; resistor R95 is connected between the sampling signal Uf and the inverting input terminal of the operational amplifier to introduce the Uf signal into the addition operation; Capacitor C81, resistor R3, resistor R85 and resistor R88 form an RC filter circuit for filtering high-frequency noise in the input signal; capacitor C84 is connected between +12V and the non-inverting input terminal of the operational amplifier; capacitor C88 is connected between the output terminal of the operational amplifier and GND as an output filter capacitor; the combination of resistor R3, resistor R85 and resistor R88 forms a voltage divider network in the circuit; R89 and C84 together form another filter circuit; The external signal Ui and the sampling signal Uf enter the inverting input terminal of the operational amplifier through the resistor R93 and the resistor R95 respectively.

7. The amplifier system according to claim 6, characterized in that: In the power output same-direction amplifier circuit: The input signal first enters the non-inverting input terminal of the core operational amplifier U23 of the first amplification channel through the input resistor R77, and at the same time, another input signal enters the non-inverting input terminal of the core operational amplifier U24 of the second amplification channel through the input resistor R87; the feedback resistor R80 is connected to the inverting input terminal of U23 to form a negative feedback; the feedback resistor R90 is connected to the inverting input terminal of U24 to also form a negative feedback; The amplified signal is output from the output end of U23 through the output resistor R81 to form the output signal Uo of the first channel; the output signal of the second channel is output from the output end of U24 through the output resistor R91; The circuit includes multiple filter capacitors and power supply capacitors which are connected in parallel to the power supply line; the power supplies +Vs and -Vs are directly connected to the corresponding power supply lines through resistors R86 and respectively, to provide the required power supply voltage for the operational amplifier.

8. The amplifier system according to claim 7, characterized in that: In the power output reverse amplifier circuit: Uo is the output signal of the adding amplifier and passes through the filter circuit composed of resistor R97 and capacitor C91; The filtered signal enters U27 power op amp OPA541 to receive Uo signal and reverse amplify it; The reversely amplified signal enters the subsequent circuit, where the connection method of the resistor R100 and the capacitor C96 components helps to increase the output current; the power amplifier U28 is used to further increase the output current; the output signal Ub is connected to the motor phase B through the reverse freewheeling diode.

9. The amplifier system according to claim 8, characterized in that: In the current sampling circuit: The in-phase amplifier output Ua is connected to one end of the sampling resistor R84; The other end of the sampling resistor R84 is connected to the positive electrode of the reverse freewheeling diode; The cathode of the reverse freewheeling diode is connected to phase A of the motor; The differential operational amplifier U22 is used to convert the voltage difference across the sampling resistor R84 into a single-ended signal; the non-inverting input terminal of U22 is connected to one end of R84, and the inverting input terminal is connected to the ground through the resistor R57; the output terminal of U22 is connected to the inverting input terminal of the operational amplifier U21; The non-inverting operational amplifier U21 is used to amplify the single-ended signal output by the differential operational amplifier U22; the non-inverting input terminal of U21 is connected to the output terminal of U22, and the inverting input terminal is connected to the ground through the resistor R71; the output terminal of U21 is connected to the analog switch U20.

10. The amplifier system according to claim 9, characterized in that: The analog switch U20 is used to select different amplification factors according to external configuration, thereby configuring the volt-ampere ratio; the output end of U20 is connected to the subsequent circuit.

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