CN217522761U - Servo driving system - Google Patents

Abstract

The utility model provides a servo driving system, which comprises a communication unit used for receiving control information sent by an upper computer; sending the control information to the STM32F103 main control unit; the STM32F103 main control unit is used for generating a first PWM signal according to the control information and sending the first PWM signal to the power driving unit; the power driving unit is used for conducting an MOSFET (metal oxide semiconductor field effect transistor) tube in the power driving unit according to the first PWM (pulse width modulation) signal so as to enable the servo motor to operate; the sensor acquisition unit is used for acquiring the actual value of the working parameter of the servo motor and sending the actual value to the STM32F103 main control unit; the STM32F103 main control unit is further used for generating a second PWM signal according to the difference value between the target value and the actual value, and sending the second PWM signal to the power driving unit so that the actual value of the working parameter of the servo motor reaches the target value.

Description

Servo driving system

Technical Field

The utility model relates to a mobile robot technical field especially relates to a servo drive system.

Background

An Automated Guided Vehicle (AGV) is a transport Vehicle equipped with an electromagnetic or optical automatic navigation device, capable of traveling along a predetermined navigation path, and having safety protection and various transfer functions. Most servo driving systems applied to AGVs in the prior art are configured by Digital Signal Processing (DSP), Field Programmable Gate Array (FPGA), and Insulated Gate Bipolar Transistor (IGBT), but the development cost of the servo driving system of this configuration is usually high.

Furthermore, existing servo drive systems are typically bulky, which can be disadvantageous for installation and integration within an AGV and can result in a reduction in servo drive power density. Wherein, the power density refers to the ratio of the maximum power output by the servo drive system to the mass or volume of the servo drive system.

Therefore, how to design a servo driving system that can not only increase the power density but also reduce the development cost is urgently needed.

SUMMERY OF THE UTILITY MODEL

An embodiment of the utility model provides a servo drive system for solve current servo drive system power density low and with high costs problem.

The utility model provides a servo drive system includes: the system comprises an STM32F103 main control unit, a communication unit, a power driving unit and a sensor acquisition unit;

the communication unit is used for receiving control information sent by the upper computer; sending the control information to the STM32F103 main control unit; the control information comprises a target value of the working parameter of the servo motor; the STM32F103 main control unit is connected to the communication unit, and configured to generate a first Pulse Width Modulation (PWM) signal according to the control information, and send the first PWM signal to the power driving unit; the first PWM signal is used for enabling the actual value of the working parameter of the servo motor to reach the target value; the power driving unit is connected with the STM32F103 main control unit and the servo motor and is used for conducting a field effect MOSFET in the power driving unit according to the first PWM signal so as to enable the servo motor to operate; the sensor acquisition unit is connected with the STM32F103 main control unit and the servo motor, and is used for acquiring the actual values of the working parameters of the servo motor and sending the actual values to the STM32F103 main control unit; the STM32F103 main control unit is further configured to generate a second PWM signal according to the difference between the target value and the actual value, and send the second PWM signal to the power driving unit, so that the actual value of the working parameter of the servo motor reaches the target value.

Based on the design, the STM32F103 is adopted in the main control unit of the servo driving system, the MOSFET is adopted in the power driving unit, and compared with the structure of combining the FPGA and the IGBT in the prior art, the structure of the STM32F103 and the MOSFET has lower cost, so that the cost of the servo driving system can be reduced by adopting the structure.

In one design, the operating parameters include: the current of the servo motor, the rotor position of the servo motor and the rotating speed of the servo motor.

Based on the design, the servo driving system can control the current of the servo motor, the rotor position of the servo motor and the rotating speed of the servo motor.

In one design, the STM32F103 master unit includes an encoder unit; the encoder unit is used for acquiring an actual value of the rotor position of the servo motor and an actual value of the rotating speed of the servo motor.

Based on the design, the position and the rotating speed of the servo motor rotor can be acquired through the encoder unit, so that the servo driving system can control the position and the rotating speed of the servo motor rotor.

In one design, the communication unit includes a Controller Area Network (CAN) bus transceiver that interfaces with the CAN bus; the CAN bus transceiver is used for receiving control information from the upper computer.

Based on the design, the servo driving system adopts the CAN bus for communication, so that the communication speed of the servo driving system and an upper computer CAN be improved, and remote communication CAN be supported.

In one design, the STM32F103 master control unit and the communication unit are integrated on a first circuit board, and the power drive unit and the sensor acquisition unit are integrated on a second circuit board; the heat conductivity coefficient of the plate of the second circuit board is larger than that of the plate of the first circuit board.

Based on the design, the circuit board where the power driving unit is located is made of the board with the high melting point and the large heat conductivity coefficient, so that the servo driving system can output large current and reduce the volume of the servo driving system, and the power density of the servo driving system is improved.

In one design, the power driving unit includes a plurality of MOSFET tubes; and a heat-conducting silica gel gasket is arranged between the MOSFET tubes and the metal shell of the servo driving system.

Based on the design, the heat conduction silica gel gasket is placed between the metal shell of the MOSFET tube and the metal shell of the servo driving system, so that the heat dissipation area can be increased, the servo driving system can output large current and reduce the volume of the servo driving system, and the power density of the servo driving system is improved.

In one design, the communication unit is further configured to receive configuration information sent by an upper computer, and send the configuration information to the STM32F103 main control unit; the configuration information is used for configuring parameters of the servo driving system; the servo driving system also comprises an electrified erasable programmable read-only EEPROM memory; the STM32F103 main control unit is connected with the EEPROM through an integrated circuit bus IIC interface in the STM32F103 main control unit, and is used for receiving the configuration information sent by the communication unit and sending the configuration information and the actual value of the working parameter to the EEPROM; the EEPROM is used for receiving the configuration information and the actual value of the working parameter and storing the configuration information and the actual value of the working parameter.

Based on the design, the EEPROM can still be used for storing the configuration information of the servo drive system and the actual values of the working parameters of the servo motor when the servo drive system is powered off, and the problem that the servo drive system needs to be reset after being powered on again every time can be solved.

In one design, the system further comprises a safety protection unit, wherein the safety protection unit is connected with the sensor acquisition unit and the STM32F103 main control unit; the working parameters comprise the current of the servo motor, the voltage of the servo motor and the temperature of the servo motor; when a first condition is met, the safety protection unit sends an interrupt signal to the STM32F103 main control unit through an external interrupt EXTI interface of the STM32F103 main control unit; the STM32F103 main control unit receives the interrupt signal and stops sending the first PWM signal or the second PWM signal; the first condition includes one or more of: the actual value of the voltage of the servo motor is greater than a first threshold value; or the actual value of the temperature of the servo motor is larger than a second threshold value; alternatively, the actual value of the current of the servo motor is greater than a third threshold value.

Based on the design, the safety protection unit can interrupt the output of the PWM signal when the servo motor has overlarge voltage, overlarge current or overhigh temperature. The condition that the servo motor breaks down due to continuous operation of the servo motor under the conditions of overlarge voltage, overlarge current or overhigh temperature can be avoided.

Drawings

Fig. 1 is a schematic structural diagram of a servo drive system according to an embodiment of the present invention;

fig. 2 is a schematic structural diagram of a servo driving system according to an embodiment of the present invention.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention clearer, the present invention will be described in further detail with reference to the accompanying drawings, and it is obvious that the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by a person skilled in the art without creative efforts belong to the protection scope of the present invention.

Unless otherwise defined, technical or scientific terms used herein shall have the ordinary meaning as understood by those of ordinary skill in the art to which this disclosure belongs. The use of "first," "second," and similar terms in the present disclosure does not denote any order, quantity, or importance, but rather the terms are used to distinguish one element from another. The word "comprising" or "comprises", and the like, means that the element or item listed before the word covers the element or item listed after the word and its equivalents, but does not exclude other elements or items.

At present, most of servo drive systems applied to AGVs are configured by combining a DSP with an FPGA and an IGBT, but the development cost of the servo drive system with the configuration is usually high. And because the AGV industry has strict requirements on volume and power density, the servo drive system applied to the AGV is required to have small volume and output larger power. However, the servo driving system in the prior art is generally large in size and low in power density. Therefore in order to solve the problem that current servo drive system power density is low and with high costs, the embodiment of the utility model provides a servo drive system.

Fig. 1 is a schematic structural diagram of a servo drive system according to an embodiment of the present invention. The servo drive system 100 shown in fig. 1 can be applied to an AGV, including: the system comprises a communication unit 101, an STM32F103 main control unit 102, a power driving unit 103 and a sensor acquisition unit 104. The STM32F103 main control unit 102 is connected with the communication unit 101, the power driving unit 103 and the sensor acquisition unit 104. The communication unit 101 is connected with an upper computer, and the power driving unit 103 and the sensor acquisition unit 104 are respectively connected with the servo motor.

The communication unit 101 is configured to receive control information and configuration information sent by an upper computer, and send the control information and the configuration information to the STM32F103 main control unit 102. In addition, the communication unit 101 may also be configured to receive working state information of the servo drive system fed back by the STM32F103 main control unit 102, and send the working state information to the upper computer. The control information may include a target value of an operating parameter of the servo motor, among others. For example, the control information may include a target value of the current of the servo motor in order for the upper computer to control the torque of the servo motor. The upper computer is used for controlling the position of the rotor of the servo motor, and the control information can comprise a target value of the position of the rotor of the servo motor. The upper computer is used for controlling the rotating speed of the servo motor, and the control information can comprise a target value of the rotating speed of the servo motor. The configuration information is used for configuring parameters of the servo drive system. For example, the configuration information may include an operation mode of the servo drive system, a code corresponding to a servo motor connected to the servo drive system, and the like. The operating state information of the servo drive system may include voltage, current, temperature, etc. information of the servo drive system.

The STM32F103 is configured to receive the control information and the configuration information sent by the communication unit 102, and feed back the operating state information of the servo drive system to the communication unit 101. The STM32F103 main control unit 102 may further be configured to control a timer of the STM32F103 main control unit 102 to generate a first PWM signal according to the control information, and send the first PWM signal to the power driving unit 103. The first PWM signal is used for enabling an actual value of the working parameter of the servo motor to reach a target value.

The power driving unit 103 is used for receiving a first PWM signal sent by the main control unit 102 of the STM32F103, and turning on a MOSFET in the power driving unit 103 according to the first PWM signal, so that the servo motor operates. The power driving unit 103 may include a plurality of MOSFET transistors, for example, 6 MOSFET transistors, 12 MOSFET transistors, or 24 MOSFET transistors. It should be understood that the number of MOSFET tubes can be set according to actual conditions.

The sensor acquisition unit 104 is used for acquiring an actual value of a working parameter of the servo motor and sending the actual value to the STM32F103 main control unit 102. The actual values of the operating parameters of the servo motor may include an actual value of a current, an actual value of a temperature, an actual value of a voltage, and the like.

The STM32F103 main control unit 102 is further configured to receive an actual value of a working parameter of the servo motor sent by the sensor acquisition unit 104, generate a second PWM signal according to a difference between the actual value and a target value, and send the second PWM signal to the power driving unit 103.

The power driving unit 103 then turns on the MOSFET transistor according to the second PWM signal to operate the servo motor. Then, the sensor acquiring unit 104 continues to acquire the actual value of the operating parameter of the servo motor, and if there is still a difference between the actual value and the target value, the above operations are continuously executed until the actual value of the operating parameter of the servo motor reaches the target value.

Based on the embodiment, the STM32F103 is adopted as the main control unit of the servo drive system, the MOSFET is adopted as the power drive unit, and compared with the architecture of combining the DSP with the FPGA and the IGBT in the prior art, the architecture of the STM32F103 and the MOSFET has lower cost, so the cost of the servo drive system can be reduced by adopting the architecture.

In one possible scenario, the communication unit 101 in fig. 1 may include a CAN bus transceiver, a serial communication interface RS232 conversion chip, and an RS485 conversion chip. The CAN bus transceiver is connected with a CAN bus interface of the STM32F103 main control unit, and the RS232 conversion chip and the RS485 conversion chip are connected with a Universal Synchronous/Asynchronous serial Receiver/Transmitter (USART) interface of the STM32F103 main control unit. The CAN bus transceiver is used for completing communication of a CAN bus, the RS232 conversion chip is used for completing communication of an RS232 bus, and the RS485 conversion chip is used for completing communication of an RS485 bus. Therefore, the communication unit is also used for completing the driving of the CAN bus, the RS232 bus and the RS485 bus. After the driving is finished, the communication unit CAN adopt any one of a CAN bus, an RS232 bus and an RS485 bus to receive the control information and the configuration information sent by the upper computer and feed back the working state information of the servo driving system. It should be understood that the RS232 bus is suitable for short-distance communication, the CAN bus and the RS485 bus are suitable for long-distance communication, the communication speed is high, and buses required by the servo drive system CAN be selected according to actual conditions.

Based on the embodiment, the servo driving system adopts the CAN bus for communication, so that the communication speed of the servo driving system and the upper computer CAN be improved, and remote communication CAN be supported. The servo driving system can also communicate with an upper computer by adopting an RS232 bus and an RS485 bus, so that the adaptability of the servo driving system can be enhanced.

In one possible implementation manner, the STM32F103 main control unit 102 in fig. 1 may include a CAN bus Interface, a USART Interface, a Timer, a PWM Interface, an Analog-to-Digital Converter (ADC) Interface, an ENCODER unit (ENCODER), an external interrupt (BREAK) Interface, an Input/Output (I/O) Interface, a Serial Peripheral Interface (SPI) Interface, an Integrated Circuit bus (Inter-Integrated Circuit, IIC) Interface, a Joint Test Activity Group (JTAG) Interface, and a Watchdog (Watchdog Timer, WDG).

Wherein, CAN bus interface and USART interface are used for connecting the communication unit, communicate with the host computer. The timer can be used for generating a first PWM signal according to control information sent by the upper computer or generating a second PWM signal according to a target value and an actual value of an operating parameter of the servo motor, and then sending the first PWM signal or the second PWM signal to the power driving unit through the PWM interface. Wherein, the duty ratio of the first PWM signal and the second PWM signal can be different. For example, the STM32F103 master unit may generate a plurality of first PWM signals through the advanced timer TIM1 and the advanced timer TIM8 in the timer, and respectively transmit the plurality of first PWM signals to the plurality of MOSFET transistors in the power driving unit through the PWM interface.

The ADC interface can be used for acquiring parameters such as voltage and current of the servo driving system. The ADC interface may also be configured to connect the sensing acquisition unit, and convert an analog of an actual value of a working parameter of the servo motor sent by the sensing acquisition unit into a digital value, so that the STM32F103 main control unit may control the servo motor by using a proportional-Integral-Derivative (PID) controller inside according to the actual value and a target value of the working parameter of the servo motor. When the control information includes the target value of the current of the servo motor, the STM32F103 main control unit may generate a second PWM signal according to a difference between the actual value of the current of the servo motor sent by the sensing acquisition unit received by the ADC interface and the target value of the current of the servo motor, so that the actual value of the current of the servo motor reaches the target current value.

The encoder unit is connected with the servo motor, can comprise a plurality of magnetic encoder chips, and is used for acquiring data such as an actual value of the position of a rotor of the servo motor, the rotating speed of the servo motor and the like, and storing the data when the servo drive system is powered on or powered off. The actual value of the rotor position may comprise data of an absolute angular position of the rotor, a number of revolutions of the rotor, etc. When the control information includes the target position of the rotor of the servo motor, the STM32F103 main control unit may generate a second PWM signal according to a difference between the target value of the rotor position of the servo motor and the actual value of the rotor position acquired by the encoder unit, so that the actual value of the rotor position of the servo motor reaches the target position. When the control information includes the target rotation speed of the servo motor, the STM32F103 main control unit may generate a second PWM signal according to a difference between the target value of the rotation speed of the servo motor and the actual value of the rotation speed of the servo motor acquired by the encoder unit, so that the actual value of the rotation speed of the servo motor reaches the target rotation speed.

The BREAK interface is used for sending a brake signal to stop the servo motor when the servo motor is abnormal. For example, when the AGV runs in a vertical running state, an internal contracting brake signal can be sent through the BREAK interface, so that the AGV stops running. The general purpose I/O interface may be used to connect other external devices. Both the SPI interface and the IIC interface may be used to communicate with peripheral devices in a serial manner. For example, the servo drive system can be connected with a Flash memory (Flash) through an SPI interface or an IIC interface, so that some information such as parameters or configuration of the servo drive system is transmitted to the Flash for storage. And the JTAG interface is used for testing and debugging the system before the actual application of the servo driving system. The WDG is used to detect whether the servo drive system is transmitting a fault.

In one possible implementation, the power driving unit 103 shown in fig. 1 may further include a level shifting unit. For level conversion of the received PWM signal, for example, a 3.3V PWM signal output by the STM32F103 main control unit may be converted into a 5V PWM signal. The power driving unit 103 shown in fig. 1 may further include an optical coupler for realizing unidirectional transmission of signals, so that the input end and the output end of the power driving unit may be electrically isolated, that is, the output signal has no influence on the input end, and thus the anti-interference capability of the servo driving system may be enhanced.

In some embodiments, after receiving the PWM signal sent by the STM32F103 main control unit, the power driving unit may convert the level of the PWM signal through the level conversion unit, isolate the PWM signal through the optical coupling, amplify the power of the PWM signal through the power amplifier in the power driving unit, and send the amplified power to the H-bridge constructed by the plurality of MOSFET transistors in the power driving unit. The MOSFET tube can be switched on through the PWM signal, so that the servo motor can operate. For example, when the power driving unit includes 6 MOSFET transistors, the timer of the STM32F103 main control unit may generate 6 PWM signals and send to the power driving unit, where each MOSFET transistor corresponds to one PWM signal. The 6 PWM signals are transmitted to MOSFET tubes in the power driving unit after level conversion, signal isolation and power amplification in the power driving unit, and the MOSFET tubes are conducted, so that the phase sequence of a servo motor connected with the power driving unit is sequentially conducted, and the rotation of the motor is controlled.

In one possible implementation, the sensor acquisition unit 104 shown in fig. 1 may include a voltage sensor, a current sensor, and a temperature sensor. The actual values of the operating parameters of the servo motor collected by the sensor collecting unit may include actual values of voltage, current and temperature. The actual value of the voltage of the servo motor acquired by the sensor acquisition unit is the input voltage of the servo motor when the servo drive system is powered on. The actual value of the current and the actual value of the temperature of the servo motor, which are acquired by the sensor acquisition unit, are acquired through connection with the servo motor. The actual values of the current may include a bus current value and a phase current value. The sensor acquisition unit can be used for carrying out filtering amplification and other processing on the acquired actual values of the working parameters of the servo motor and then sending the actual values to an ADC (analog to digital converter) interface of the STM32F103 main control unit.

In an example, refer to fig. 2 for one of the schematic structural diagrams of the servo driving system provided by the embodiment of the present invention. The servo drive system 200 shown in FIG. 2, which may be applied to an AGV, includes: the system comprises a power management unit 201, a communication unit 202, an STM32F103 main control unit 203, a power driving unit 204, a sensor acquisition unit 205, a charged Erasable Programmable Read-Only (EEPROM) Memory 206 and a safety protection unit 207. In the servo driving system shown in fig. 2, the communication unit 202 includes a CAN transceiver and an RS232 conversion chip. In addition, the communication unit 202 may be the communication unit 101 shown in fig. 1, the STM32F103 main control unit 203 may be the STM32F103 main control unit 102 shown in fig. 1, the power driving unit 204 may be the power driving unit 103 shown in fig. 1, and the sensor acquisition unit 205 may be the sensor acquisition unit 104 shown in fig. 1, which is not described herein again.

The power management unit 201 is used for supplying power to each component of the servo drive system and charging a battery of the servo drive system after the servo drive system 200 is powered on.

The EEPROM 206 may be connected to the STM32F103 main control unit 203 through an IIC interface of the STM32F103 main control unit 203, and is configured to store information, such as configuration information sent by the STM32F103 main control unit 203, an actual value of a rotor position of the servo motor acquired by the encoder unit, and an actual value of a rotation speed of the servo motor acquired by the encoder unit. Optionally, the STM32F103 main control unit 203 sends the received configuration information, the actual value of the rotor position of the servo motor, the actual value of the rotation speed of the servo motor, and other information to the EEPROM 206. Alternatively, the STM32F103 main control unit 203 may send, to the EEPROM memory 206, information such as the changed configuration information, the actual value of the rotor position of the servo motor, and the actual value of the rotational speed of the servo motor in real time after changing the information such as the configuration information, the actual value of the rotor position of the servo motor, and the actual value of the rotational speed of the servo motor.

Based on the above embodiment, the EEPROM 206 can prevent information such as configuration information of the servo drive system, an actual value of a rotor position of the servo motor, and an actual value of a rotational speed of the servo motor from being lost when the servo drive system is powered off.

The security protection unit 207 is connected to the sensor acquisition unit 205, and may also be connected to the STM32F103 main control unit 203 through an External interrupt (EXTI) interface of the STM32F103 main control unit 203. Wherein the EXTI interface may be included in the general I/O interface of the STM32F103 master unit 203. The safety protection unit 207 may include a first overvoltage protection circuit, a first overcurrent protection circuit, and an overtemperature protection circuit. The first overvoltage protection circuit can receive the actual value of the voltage of the servo motor acquired by the sensor acquisition unit, the actual value of the voltage can be compared with a first threshold value in the first overvoltage protection circuit, and when the actual value of the voltage is larger than the first threshold value, an interrupt signal can be sent to an EXTI interface of the STM32F103 main control unit 203, so that the STM32F103 main control unit 203 stops sending the first PWM signal or the second PWM signal. The first overcurrent protection circuit can receive the actual value of the current of the servo motor acquired by the sensor acquisition unit, the actual value of the current can be compared with a second threshold value in the first overcurrent protection circuit, and when the actual value of the current is greater than the second threshold value, an interrupt signal can be sent to an EXTI interface of the STM32F103 main control unit 203, so that the STM32F103 main control unit 203 stops sending the first PWM signal or the second PWM signal. The over-temperature protection circuit can receive the actual value of the temperature of the servo motor acquired by the sensor acquisition unit, the actual value of the temperature can be compared with a third threshold value in the over-temperature protection circuit, and when the actual value of the temperature is greater than the third threshold value, an interrupt signal can be sent to an EXTI interface of the STM32F103 main control unit 203, so that the STM32F103 main control unit 203 stops sending the first PWM signal or the second PWM signal. It should be understood that the first threshold, the second threshold and the third threshold are all preset according to actual conditions, and the present invention is not limited herein.

Based on the embodiment, the safety protection unit can interrupt the output of the PWM signal when the servo motor has overlarge voltage, overlarge current or overhigh temperature. The condition that the servo motor breaks down due to the fact that the servo motor continues to operate under the conditions of overlarge voltage, overlarge current or overhigh temperature can be avoided.

In some embodiments, the safety protection unit 207 may further include an under-voltage protection circuit, a second over-current protection circuit, and a second over-voltage protection circuit. The method is used for determining whether the servo driving system has overvoltage, undervoltage or overcurrent according to the current and voltage of the servo driving system collected by the ADC interface of the STM32F103 main control unit 203. For example, the undervoltage protection circuit may compare the voltage of the servo drive system collected by the ADC interface with a fourth threshold, and when the voltage of the servo drive system is smaller than the fourth threshold, may send an interrupt signal to the STM32F103 main control unit 203 through the EXTI interface, so that the STM32F103 main control unit 203 stops sending the first PWM signal or the second PWM signal. The second overvoltage protection circuit can compare the voltage of the servo drive system collected by the ADC interface with a fifth threshold, and when the voltage of the servo drive system is greater than the fifth threshold, can send an interrupt signal to the EXTI interface of the STM32F103 main control unit 203, so that the STM32F103 main control unit 203 stops sending the first PWM signal or the second PWM signal. The second overcurrent protection circuit may compare the current of the servo drive system collected by the ADC interface with a sixth threshold, and when the current of the servo drive system is greater than the sixth threshold, may send an interrupt signal to the EXTI interface of the STM32F103 main control unit 203, so that the STM32F103 main control unit 203 stops sending the first PWM signal or the second PWM signal. It should be understood that the fourth threshold, the fifth threshold and the sixth threshold are preset according to actual conditions, and the present invention is not limited thereto.

Based on the design, the safety protection unit can interrupt the output of the PWM signal when the servo driving system has overlarge voltage, overlow voltage or overhigh temperature. The problem that the servo driving system fails due to the fact that the servo driving system continues to operate under the conditions of overlarge voltage, overlow voltage or overhigh temperature can be solved.

In one possible implementation, the power management unit 201, the communication unit 202, the STM32F103 main control unit 203, the EEPROM memory 206, and the security protection unit 207 shown in fig. 2 may be integrated on the first circuit board. The power driving unit 204 and the sensor acquisition unit 205 may be integrated on the second circuit board. In order to reduce the volume of the servo driving system and simultaneously not reduce the current output by the servo driving system, a plate material with high melting point and high heat conductivity coefficient can be adopted as the second circuit board. For example, copper may be laid on the circuit board below each MOSFET tube in the power driving unit, and the advantage of high thermal conductivity of copper may be utilized to increase the heat dissipation area and heat dissipation efficiency of the second circuit board.

In some embodiments, a thermally conductive silicone gasket may also be placed between the MOSFET tubes of the power drive unit of the second circuit board and the metal housing of the servo drive system. So that the heat dissipation area and the heat dissipation efficiency of the second circuit board can be increased.

Based on the embodiment, the heat conduction silica gel gasket is arranged between the MOSFET tube and the metal shell of the servo driving system, so that the servo driving system can output large current and reduce the volume of the servo driving system, and the power density of the servo driving system is improved.

The embodiment of the utility model provides a servo drive system includes: the system comprises an STM32F103 main control unit, a communication unit, a power driving unit and a sensor acquisition unit; the communication unit is used for receiving the control information sent by the upper computer; sending the control information to the STM32F103 main control unit; the STM32F103 main control unit is connected with the communication unit and used for generating a first Pulse Width Modulation (PWM) signal according to the control information and sending the first PWM signal to the power driving unit; the power driving unit is connected with the STM32F103 main control unit and the servo motor and used for conducting a field effect MOSFET in the power driving unit according to the first PWM signal so as to enable the servo motor to operate; the sensor acquisition unit is connected with the STM32F103 main control unit and the servo motor, and is used for acquiring the actual value of the working parameter of the servo motor and sending the actual value to the STM32F103 main control unit; the STM32F103 main control unit is further used for generating a second PWM signal according to the difference value between the target value and the actual value, and sending the second PWM signal to the power driving unit so that the actual value of the working parameter of the servo motor reaches the target value. The embodiment of the utility model provides a servo drive system main control unit has adopted STM32F103, and power drive unit has adopted MOSFET, because STM32F103 and MOSFET compare in prior art's DSP combine FPGA and IGBT's framework cost lower, consequently adopt this framework can reduce servo drive system's cost.

While the preferred embodiments of the present invention have been described, additional variations and modifications in those embodiments may occur to those skilled in the art once they learn of the basic inventive concepts. It is therefore intended that the appended claims be interpreted as including the preferred embodiment and all such alterations and modifications as fall within the scope of the invention.

It will be apparent to those skilled in the art that various changes and modifications may be made in the present application without departing from the spirit and scope of the application. Thus, if such modifications and variations of the present application fall within the scope of the claims of the present application and their equivalents, the present application is intended to include such modifications and variations as well.

Claims (8)

1. A servo drive system, comprising: the system comprises an STM32F103 main control unit, a communication unit, a power driving unit and a sensor acquisition unit;

the communication unit is used for receiving control information sent by the upper computer; sending the control information to the STM32F103 main control unit; the control information comprises a target value of a working parameter of the servo motor;

the STM32F103 main control unit is connected with the communication unit and used for generating a first PWM signal according to the control information and sending the first PWM signal to the power driving unit; the first PWM signal is used for enabling an actual value of the working parameter of the servo motor to reach the target value;

the power driving unit is connected with the STM32F103 main control unit and the servo motor and is used for conducting a field effect MOSFET in the power driving unit according to the first PWM signal so as to enable the servo motor to operate;

the sensor acquisition unit is connected with the STM32F103 main control unit and the servo motor, and is used for acquiring the actual values of the working parameters of the servo motor and sending the actual values to the STM32F103 main control unit;

the STM32F103 main control unit is further configured to generate a second PWM signal according to the difference between the target value and the actual value, and send the second PWM signal to the power driving unit, so that the actual value of the working parameter of the servo motor reaches the target value.

2. The system of claim 1, wherein the operating parameters comprise: the current of the servo motor, the rotor position of the servo motor and the rotating speed of the servo motor.

3. The system in accordance with claim 2, wherein the STM32F103 master unit comprises an encoder unit;

the encoder unit is used for acquiring an actual value of the rotor position of the servo motor and an actual value of the rotating speed of the servo motor.

4. The system of claim 1 wherein the communication unit comprises a Controller Area Network (CAN) bus transceiver that interfaces with a CAN bus of the STM32F103 master control unit; the CAN bus transceiver is used for receiving control information from the upper computer.

5. The system of claim 1, wherein the STM32F103 master control unit and the communication unit are integrated on a first circuit board, and the power drive unit and the sensor acquisition unit are integrated on a second circuit board; the heat conductivity coefficient of the plate of the second circuit board is larger than that of the plate of the first circuit board.

6. The system of claim 1, wherein the power driving unit comprises a plurality of MOSFET tubes; and a heat-conducting silica gel gasket is arranged between the MOSFET tubes and the metal shell of the servo driving system.

7. The system according to claim 3, wherein the communication unit is further configured to receive configuration information sent by an upper computer, and send the configuration information to the STM32F103 main control unit; the configuration information is used for configuring parameters of the servo driving system;

the servo driving system also comprises an electrified erasable programmable read-only EEPROM memory;

the STM32F103 main control unit is connected with the EEPROM through an integrated circuit bus IIC interface in the STM32F103 main control unit, and is used for receiving the configuration information sent by the communication unit and sending the configuration information and the actual value of the working parameter to the EEPROM;

the EEPROM is used for receiving the configuration information and the actual value of the working parameter and storing the configuration information and the actual value of the working parameter.

8. The system according to any one of claims 1-7, further comprising a security protection unit connected to the sensor acquisition unit and the STM32F103 master control unit;

the working parameters comprise the current of the servo motor, the voltage of the servo motor and the temperature of the servo motor;

when a first condition is met, the safety protection unit sends an interrupt signal to the STM32F103 main control unit through an external interrupt EXTI interface of the STM32F103 main control unit;

the STM32F103 main control unit receives the interrupt signal and stops sending the first PWM signal or the second PWM signal;

the first condition includes one or more of:

the actual value of the voltage of the servo motor is greater than a first threshold value; alternatively, the first and second liquid crystal display panels may be,

the actual value of the temperature of the servo motor is greater than a second threshold value; alternatively, the first and second electrodes may be,

the actual value of the current of the servo motor is greater than a third threshold value.

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