A servo integrated drive circuit based on PID control

Abstract

The present application discloses a servo integrated drive circuit based on PID control, comprising: a Hall encoding circuit, a PID control circuit, an optocoupler isolator, a drive circuit and a power conversion circuit integrated in the same drive chip. The Hall encoding circuit and the drive circuit are respectively connected to the servo; the Hall encoding circuit is used to detect the position and speed of the servo in real time; the PID control circuit is used to adjust the output PWM signal according to the input working control instruction and the feedback control instruction output by the Hall encoding circuit, and is connected to the drive circuit through the optocoupler isolator; the drive circuit is used to control the position and speed of the servo according to the PWM signal output by the PID control circuit. This solution can greatly simplify the structure of the servo drive circuit, reduce manufacturing costs, and improve system reliability and integration.

Description

Technical Field

[0001] The present invention relates to the technical field of steering gear control, and in particular to a steering gear integrated drive circuit based on PID control. Background Art

[0002] PID control is a feedback control method, including three control parts: proportional, integral and differential. The control output is calculated based on the current deviation, the integral of the deviation and the differential of the deviation. By adjusting the proportional, integral and differential coefficients, the stability, accuracy and response speed of the system can be adjusted.

[0003] By applying PID control to brushless DC motor drivers, precise control of motor speed or position can be achieved by adjusting the motor input voltage or current. However, existing PID controllers have overshoot or undershoot and oscillation caused by improper parameter adjustment, and the response speed is limited by parameter settings, resulting in PID control being unable to provide sufficient adaptability and robustness. In addition, the integrated drive circuit of the servo based on PID control has a complex circuit structure, many leads, and large signal interference, which cannot guarantee the stability and reliability of the servo control. Summary of the invention

[0004] In order to solve the above problems in the prior art, this solution proposes a servo integrated drive circuit based on PID control, which can make the circuit structure of the entire drive system compact, with fewer leads and high integration, which is conducive to reducing manufacturing costs and improving system reliability.

[0005] The present invention provides a servo integrated drive circuit based on PID control, comprising: a Hall encoding circuit, a PID control circuit, an optocoupler isolator, a drive circuit and a power conversion circuit integrated in the same drive chip.

[0006] The Hall encoding circuit and the driving circuit are respectively connected to the servo; the Hall encoding circuit is used to detect the position and speed of the servo in real time; the PID control circuit is used to receive working control instructions and feedback control instructions, output PWM signals and commutation signals according to the working control instructions and feedback control instructions, and is connected to the driving circuit through an optocoupler isolator; the driving circuit is used to control the speed and direction of the servo according to the PWM signals and commutation signals output by the PID control circuit.

[0007] By integrating the Hall encoding circuit, PID control circuit, drive circuit and power conversion circuit into the same drive chip, the servo circuit structure can be greatly simplified, the manufacturing cost can be reduced and the system reliability can be improved.

[0008] Optionally, in the PID control-based servo integrated drive circuit provided by the present invention, the Hall encoding circuit includes multiple Hall sensors, a processor and an encoder, the Hall sensor is used to convert the detected position signal into an analog voltage signal, the processor is used to convert the analog voltage signal output by the Hall sensor into a digital signal, and the encoder is used to determine the rotation direction and speed of the servo according to the phase difference of the signals output by the multiple Hall sensors.

[0009] Optionally, in the PID control-based steering gear integrated drive circuit provided by the present invention, the PID control circuit includes a proportional amplifier circuit, an absolute value detection circuit, a PID controller, and a PWM conversion circuit.

[0010] The proportional amplifier circuit is used to amplify the input working control instruction and feedback control instruction signals by a preset multiple and then output them to the absolute value detection circuit; the absolute value detection circuit is used to output a commutation signal according to the error between the working control instruction and the feedback control instruction; the PID controller is used to adjust the size of the output analog signal according to the size, accumulation, and change trend of the absolute value of the error; the PWM conversion circuit is used to convert the analog signal output by the PID controller into a PWM signal.

[0011] Optionally, in the PID control-based servo integrated drive circuit provided by the present invention, the working control instruction is the target rotational position and target speed of the servo, and the feedback control instruction is the actual rotational position and actual speed of the servo output by the Hall encoding circuit.

[0012] Optionally, in the PID control-based steering gear integrated drive circuit provided by the present invention, the PID controller has a built-in model predictive control algorithm, a fuzzy control algorithm, or any one of a control algorithm based on a neural network.

[0013] Optionally, in the PID-controlled servo integrated drive circuit provided by the present invention, the drive circuit includes a signal processing circuit, a three-phase bridge output circuit and a current limiting protection circuit, and the three-phase bridge output circuit is grounded through the current limiting protection circuit; the signal processing circuit is used to filter, amplify and / or level-convert the PWM signal output by the PID control circuit and output it to the three-phase bridge output circuit, so that the three-phase bridge output circuit can adjust the speed and direction of the servo by controlling the conduction and cutoff of the power switching device.

[0014] Optionally, in the PID-controlled servo integrated drive circuit provided by the present invention, the current limiting protection circuit is a protective ground wire, one end of which is connected to the drive circuit and the other end is connected to the power ground wire.

[0015] Optionally, in the PID-controlled integrated driving circuit for the steering gear provided by the present invention, the power conversion circuit is used to convert the input DC voltage into voltages required by the Hall encoding circuit and the driving circuit respectively.

[0016] Optionally, in the PID-controlled servo integrated drive circuit provided by the present invention, the external leads of the integrated drive circuit include a three-phase motor Hall signal interface, a Hall power interface, a work control command interface, a feedback control command interface, a positive power interface, a negative power interface, a work power interface, a three-phase drive output interface, a signal ground, and a power ground. Among them, the gain adjustment interface is connected to an adjustable resistor, and the work power interface is externally connected to a filter circuit and a power supply.

[0017] The PID-controlled integrated steering gear drive circuit provided by the present invention can greatly simplify the steering gear drive circuit structure, reduce manufacturing costs, and improve system reliability and integration by isolating the PID control circuit and the drive circuit through an optocoupler isolator and integrating them into the same drive chip; the PID controller with a built-in closed-loop control algorithm adjusts the output signal according to the error signal, so that the steering gear system can respond to the control target quickly and stably, and realize precise position and speed control.

[0018] The above description is only an overview of the technical solution of the present invention. In order to more clearly understand the technical means of the present invention, it can be implemented according to the contents of the specification. In order to make the above and other purposes, features and advantages of the present invention more obvious and easy to understand, the specific implementation methods of the present invention are listed below. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 The figure shows the internal circuit structure principle diagram of the steering gear integrated drive circuit based on PID control according to one embodiment of the present invention;

[0020] Figure 2 A schematic diagram of an external interface circuit of a steering gear integrated drive circuit based on PID control according to an embodiment of the present invention is shown. DETAILED DESCRIPTION

[0021] In order to achieve precise control of the servo, this solution provides a servo integrated drive circuit based on PID control. The PID controller with a built-in closed-loop control algorithm adjusts the output signal according to the error signal, so that the servo system can respond to the control target quickly and stably and achieve precise position and speed control. The entire drive system circuit has a compact structure, few leads, and high integration, which is conducive to reducing manufacturing costs and improving system reliability.

[0022] The exemplary embodiments of the present disclosure will be described in more detail below with reference to the accompanying drawings. Although the exemplary embodiments of the present disclosure are shown in the accompanying drawings, it should be understood that the present disclosure can be implemented in various forms and should not be limited by the embodiments set forth herein. On the contrary, these embodiments are provided to enable a more thorough understanding of the present disclosure and to fully convey the scope of the present disclosure to those skilled in the art.

[0023] Figure 1 FIG. 1 shows a schematic diagram of the internal circuit structure of a steering gear integrated drive circuit based on PID control according to an embodiment of the present invention. Figure 1 As shown, the servo integrated drive circuit based on PID control includes: a Hall encoding circuit, a PID control circuit, an optocoupler isolator, a drive circuit and a power conversion circuit integrated in the same drive chip.

[0024] The Hall encoding circuit and the driving circuit are respectively connected to the servo, and the power conversion circuit is used to provide the required voltages for the Hall encoding circuit and the driving circuit respectively.

[0025] Since the DC-DC regulator has the advantages of small size, high efficiency, stable output voltage, etc., the power conversion circuit can use the DC-DC regulator to convert the input DC voltage into the voltage required by the Hall encoding circuit and the drive circuit respectively.

[0026] The Hall encoder circuit is used to detect the rotation position of the servo in real time. The PID control circuit is used to adjust the output PWM signal according to the input working control command and the feedback control command output by the Hall encoder circuit, and isolate the PID control circuit and the drive circuit through the optical coupler isolator;

[0027] The driving circuit is connected to the PID control circuit and is used for controlling the direction and speed of the servo according to the PWM output signal output by the PID control circuit.

[0028] In one embodiment of the present invention, the Hall encoding circuit includes multiple Hall sensors, a processor and an encoder, the Hall sensor is used to convert the detected position signal into an analog voltage signal, the processor is used to convert the analog voltage signal output by the Hall sensor into a digital signal, and the encoder is used to determine the rotation direction and speed of the servo according to the phase difference of the signals output by the multiple Hall sensors.

[0029] For the detection of the servo rotation, the Hall sensor can detect the servo rotation position and direction and convert it into a voltage signal. The voltage signal is processed by the processor and encoder to finally obtain a digital output for indicating the servo position and angle.

[0030] like Figure 1 As shown, the PID control circuit includes a proportional amplifier circuit, a PID controller, an absolute value detection circuit, and a PWM conversion circuit.

[0031] The proportional amplifier circuit is used to amplify the input working control instruction and feedback control instruction signals by a preset multiple and then output them to the absolute value detection circuit; the absolute value detection circuit is used to output a commutation signal according to the error between the working control instruction and the feedback control instruction.

[0032] The working control instruction is the target rotation position and target speed of the servo, and the feedback control instruction is the actual rotation position and actual speed of the servo output by the Hall encoding circuit.

[0033] The PID controller is used to adjust the size of the output analog signal according to the size, accumulation, and change trend of the absolute value of the error. The PID controller can improve the system response speed, eliminate the system steady-state error, and reduce the rate of change of the output signal through the three parts of proportion, integration, and differentiation to avoid overshoot or oscillation in the system. The PWM conversion circuit is used to convert the analog signal output by the PID controller into a PWM signal.

[0034] The PID controller has any one of the control algorithms built into it, including the model predictive control algorithm, the fuzzy control algorithm, and the control algorithm based on the neural network. For example, the steering gear control system is modeled according to the model predictive control algorithm, the system behavior is described by the state space model and the system state at the future moment is predicted, and the optimal control input at the current moment is determined by the optimization algorithm. According to the fuzzy control algorithm, the input working control instructions and feedback control instructions are mapped to the fuzzy set, the actual numerical value is converted into a fuzzy language description, and the fuzzified input is inferred according to the pre-defined fuzzy rules to obtain the fuzzified output result, and finally the fuzzified output result is converted into a specific numerical value.

[0035] The control algorithm based on neural network needs to train the neural network used for control tasks according to the input and output data of the PID controller, and continuously adjust the weight and bias of the neural network through the back propagation algorithm to make the neural network closer to the dynamic characteristics of the system. After the neural network training is completed, it is used as the controller of the system to output the corresponding adjustment parameters according to the received error signal.

[0036] Through the above control algorithm, the system can achieve fast response, stability and robustness. Parameters can be adjusted and optimized according to specific application scenarios and system characteristics.

[0037] The driving circuit includes a signal processing circuit, a three-phase bridge output circuit and a current limiting protection circuit, and the three-phase bridge output circuit is grounded through the current limiting protection circuit;

[0038] The signal processing circuit is used to filter, amplify and / or level-convert the PWM signal output by the PID control circuit and then output it to the three-phase bridge output circuit, so that the three-phase bridge output circuit can adjust the speed and direction of the servo by controlling the conduction and cutoff of the power switch device. The current limiting protection circuit is a protective ground wire, which is used to connect the metal shell of the brushless motor driver to the ground wire to prevent the motor from overcurrent, overheating, overload, etc., and improve the reliability of the servo operation.

[0039] Figure 2FIG. 1 is a schematic diagram of an external interface circuit of a steering gear integrated drive circuit based on PID control according to an embodiment of the present invention. Figure 2 As shown, the external leads of the driver chip include three-phase motor Hall signal interface (ha, hb, hc), Hall power supply interface (Vh), working control command interface (ZL), feedback control command interface (FQ), gain adjustment interface (Ao1, Ao2), positive power supply interface (Vcc), negative power supply interface (Vee), working power supply interface (Vs), three-phase drive output interface (U1, V1, W1, U2, V2, W2), signal ground (Gnd) and power ground (GND).

[0040] The gain of the proportional amplifier circuit can be adjusted by adjusting the variable resistor W1, and the capacitors C1 and C2 are used to filter the working power supply signal.

[0041] According to the PID-controlled servo integrated drive circuit provided by the present invention, the PID control circuit and the drive circuit are isolated by an optocoupler isolator and integrated into the same drive chip, which can greatly simplify the structure of the servo drive circuit, reduce manufacturing costs, and improve system reliability and integration; the PID controller with a built-in closed-loop control algorithm adjusts the output signal according to the error signal, so that the servo system can respond to the control target quickly and stably, and realize precise position and speed control.

[0042] In the description provided herein, a large number of specific details are described. However, it is understood that embodiments of the present invention can be practiced without these specific details. In some instances, well-known methods, structures and techniques are not shown in detail so as not to obscure the understanding of this description.

[0043] Those skilled in the art will appreciate that the modules in the devices in the embodiments may be adaptively changed and arranged in one or more devices different from the embodiments. The modules or units or components in the embodiments may be combined into one module or unit or component, and further may be divided into a plurality of submodules or subunits or subcomponents. All features disclosed in this specification (including the accompanying claims, abstracts and drawings) and all processes or units of any method or device so disclosed may be combined in any combination, except that at least some of such features and / or processes or units are mutually exclusive. Unless otherwise expressly stated, each feature disclosed in this specification (including the accompanying claims, abstracts and drawings) may be replaced by an alternative feature that provides the same, equivalent or similar purpose.

[0044] Furthermore, those skilled in the art will appreciate that although some embodiments herein include certain features included in other embodiments but not other features, the combination of features from different embodiments is meant to be within the scope of the present invention and to form different embodiments.

[0045] Although the present invention has been described according to a limited number of embodiments, it will be apparent to those skilled in the art, with the benefit of the above description, that other embodiments may be envisioned within the scope of the invention thus described. In addition, it should be noted that the language used in this specification is selected primarily for readability and teaching purposes, rather than for explaining or defining the subject matter of the present invention. Therefore, many modifications and variations will be apparent to those skilled in the art without departing from the scope and spirit of the appended claims. The disclosure of the present invention is illustrative and not restrictive with respect to the scope of the present invention, and the scope of the present invention is defined by the appended claims.

Claims

1. A servo integrated drive circuit based on PID control, characterized in that: include: A power conversion circuit, a Hall encoding circuit, a PID control circuit, an optocoupler isolator, and a drive circuit are integrated in the same drive chip, wherein the Hall encoding circuit and the drive circuit are respectively connected to the servo; the Hall encoding circuit is used to detect the position and speed of the servo in real time; the PID control circuit is used to receive working control instructions and feedback control instructions, output PWM signals and commutation signals according to the working control instructions and feedback control instructions, and is connected to the drive circuit through the optocoupler isolator; the drive circuit is used to control the speed and direction of the servo according to the PWM signals and commutation signals output by the PID control circuit; The PID control circuit includes a proportional amplifier circuit, an absolute value detection circuit, a PID controller, and a PWM conversion circuit; the proportional amplifier circuit is used to amplify the input working control instruction and feedback control instruction signals by a preset multiple and then output them to the absolute value detection circuit; the absolute value detection circuit is used to output a commutation signal according to the error between the working control instruction and the feedback control instruction; the PID controller is used to adjust the size of the output analog signal according to the size, accumulation, and change trend of the absolute value of the error; the PWM conversion circuit is used to convert the analog signal output by the PID controller into a PWM signal.

2. The servo integrated drive circuit based on PID control according to claim 1, characterized in that: The Hall encoding circuit includes multiple Hall sensors, a processor and an encoder. The Hall sensor is used to convert the detected position signal into an analog voltage signal. The processor is used to convert the analog voltage signal output by the Hall sensor into a digital signal. The encoder is used to determine the rotation direction and speed of the servo according to the phase difference of the signals output by the multiple Hall sensors.

3. The servo integrated drive circuit based on PID control according to claim 1, characterized in that: The working control instruction is the target rotation position and target speed of the servo, and the feedback control instruction is the actual rotation position and actual speed of the servo output by the Hall encoding circuit.

4. The servo integrated drive circuit based on PID control according to claim 1, characterized in that: The PID controller has a built-in model predictive control algorithm, a fuzzy control algorithm, and a control algorithm based on a neural network.

5. The servo integrated drive circuit based on PID control according to claim 1, characterized in that: The driving circuit comprises a signal processing circuit, a three-phase bridge output circuit and a current limiting protection circuit, and the three-phase bridge output circuit is grounded through the current limiting protection circuit; The signal processing circuit is used to filter, amplify and / or level-convert the PWM signal output by the PID control circuit and then output it to the three-phase bridge output circuit, so that the three-phase bridge output circuit can adjust the speed and direction of the servo by controlling the conduction and cutoff of the power switch device.

6. The servo integrated drive circuit based on PID control according to claim 5, characterized in that: The current limiting protection circuit is a protection ground wire, one end of which is connected to the driving circuit, and the other end is connected to the power ground wire.

7. The servo integrated drive circuit based on PID control according to claim 1, characterized in that: The power conversion circuit is used to convert the input DC voltage into voltages required by the Hall encoding circuit and the driving circuit respectively.

8. The servo integrated drive circuit based on PID control according to claim 1, characterized in that: The external leads of the integrated drive circuit include a three-phase motor Hall signal interface, a Hall power supply interface, a working control instruction interface, a feedback control instruction interface, a gain adjustment interface, a positive power supply interface, a negative power supply interface, a working power supply interface, a three-phase drive output interface, a signal ground and a power ground.

9. The servo integrated drive circuit based on PID control according to claim 8, characterized in that: The gain adjustment interface is connected to an adjustable resistor, and the working power supply interface is externally connected to a filter circuit and a power supply.

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