CN204696967U - Dual chip brshless DC motor driving control system - Google Patents

Abstract

The utility model relates to a double-chip brushless DC motor drive control system. The system adopts joint control of ARM and CPLD. The given values of torque, speed and position of the control system come from the upper computer, and the feedback value of the motor state is calculated according to the feedback value of the three-phase Hall sensor in the motor. The ARM is connected to the host computer, receives the given value sent by the host computer and performs torque control, speed control or position control according to the instructions of the host computer; CPLD receives the feedback signal of the three-phase Hall device, calculates the position and speed, and calculates The value is passed to the ARM, and the ARM combines the calculated value with the given value for control operations and sends the control word. CPLD receives the control word of ARM and parses it into a control instruction, and controls the operation of the motor through the drive circuit of the motor. The system does not need speed and position sensors, simplifies the system structure, and can realize high-precision control of torque, speed and position.

Description

Dual chip brushless DC motor drive control system

technical field

The utility model belongs to the technical field of servo control, and relates to a drive control system that adopts double-chip combination to control a brushless motor.

Background technique

A brushless DC motor consists of a rotor made of permanent magnet material, a stator with coil windings and a position sensor. While it has the superior speed regulation performance of DC motors, it also eliminates various problems caused by carbon brushes and slip ring structures. It also has the advantages of simple structure, high efficiency and reliable operation.

The speed regulation method of the brushless DC motor is usually realized by open-loop PWM modulation, and the change of the speed is realized through the external given duty ratio, but this speed regulation method is suitable for occasions that do not require high speed regulation, and cannot meet the requirements of relatively high speed. High speed regulation performance requirements, it is impossible to achieve high precision control of torque speed. At the same time, the traditional single-chip control system, special motor control system and DSP control system, when implementing fault protection, the fault protection circuit realized has a long response delay, which reduces the safety of the system.

The closed-loop speed control and closed-loop position control system of the traditional brushless DC motor needs to use the encoder as a sensor to detect the speed and position of the motor, which increases the production cost of the system when used.

Utility model content

The purpose of the utility model is to provide a brushless DC motor drive control system that can realize fast and precise speed regulation.

The technical scheme of the utility model is: a dual-chip brushless DC motor drive control system, including a host computer, a drive circuit, a voltage and current detection and comparison circuit and a control system, a brushless DC motor with a built-in three-phase Hall sensor, and the drive circuit It is a three-phase full-bridge circuit, and the control system includes a logic processor connected to each other, a microprocessor, and a drive circuit connected to the logic processor;

The logic processor includes a calculation unit, a protection unit, a drive control unit and a communication unit, wherein the calculation unit receives the feedback signal of the three-phase Hall sensor, and performs position calculation and speed calculation; the communication unit is used for communication with the microprocessor;

The upper computer is connected with the microprocessor, and the upper computer transmits the control given value signal to the microprocessor, and controls the control mode of the microprocessor;

The microprocessor receives the position and speed calculation values from the logic processor, combined with the given value of the host computer, uses the PID algorithm to calculate the control values of speed, position and torque, and feeds back the control values to the drive control unit of the logic processor , the logic processor is connected to the drive circuit through the drive circuit, the drive circuit receives the control signal given by the drive control unit, and controls the operation of the brushless DC motor through the drive circuit;

The voltage and current detection and comparison circuit includes a current detection and comparison circuit and a voltage detection and comparison circuit, both of which respectively feed back the collected current value and voltage value to the ADC acquisition terminal of the microprocessor, and simultaneously compare the current comparison value with the voltage comparison The value is passed to the logic processor, and the protection unit performs overvoltage and overcurrent judgments.

Preferably, the logic processor adopts a CPLD chip, the microprocessor adopts an ARM chip, and the two communicate through the SPI bus.

The beneficial effects of the utility model are:

(1) The utility model provides a dual-chip brushless motor drive system. ARM+CPLD dual-chip combination realizes high-precision control of torque, speed, and position, and at the same time utilizes the advantages of fast response of CPLD chips to realize fast protection of motor overvoltage and overcurrent faults;

(2) The system does not use speed and position detection sensors, and realizes accurate calculation of speed and position through the internal logic of the logic processor, thereby realizing closed-loop control of motor speed and position, which greatly reduces system cost;

(3) Customized a CPLD on-chip SPI core to adapt to the SPI communication timing, realized the SPI full-duplex communication between ARM and CPLD, and customized a full-duplex communication protocol based on the SPI bus; the The SPI core has strong portability, has a unified external interface, and can be easily transplanted to any CPLD chip to realize the SPI communication function.

Description of drawings

Fig. 1 is the structural representation of the utility model.

Fig. 2 is a schematic structural diagram of a control system in a specific embodiment.

Figure 3 is a schematic diagram of the structure of the driving circuit.

Figure 4 current detection and comparison circuit.

Figure 5 voltage detection and comparison circuit.

Detailed ways

As shown in Figure 1, the dual-chip brushless DC motor drive control system includes a host computer, a drive circuit, a voltage and current detection and comparison circuit, and a control system. The brushless DC motor has a built-in three-phase Hall sensor, and the drive circuit is a three-phase full bridge circuit.

The control system includes a logical processor connected to each other, a microprocessor, and a drive circuit connected to the logical processor. As shown in Figure 2, the logic processor uses a CPLD chip, and the microprocessor uses an ARM chip, and the two communicate through the SPI bus. The system does not use position and speed sensors, but uses the feedback value of the Hall sensor inside the brushless DC motor to calculate the position and speed. After receiving the feedback signal from the three-phase Hall sensor, the CPLD performs position calculation and speed calculation to obtain the position value and speed value of the rotor of the brushless DC motor, which is called the calculated value of position and speed here, and transmits it to the ARM.

The upper computer is connected with the ARM to control the work of the ARM, and is used to regulate the ARM for speed control, position control or torque control. When the upper computer issues a control command, it transmits the control given value to the ARM, and the ARM obtains the control values of speed, position and torque according to the given value and calculated value, according to the PID algorithm, and feeds back the control value to the CPLD. The CPLD is connected to the driving circuit through the driving circuit. The driving circuit adopts UCC27211MOSFET driver. Figure 3 is a schematic diagram of the structure of the driving circuit of bridge 1. The driving circuits of the other two bridges have the same structure as this road, but the PWM modulation signal receiving port is different. The control value received by the drive circuit is the PWM modulation signal, which comes from the PWMA0-PWMA5 terminals of the CPLD respectively. Under the control of the PWM signal generated by the CPLD, the switch of the FET is controlled so that the three-phase windings of the motor can be conducted in the required order. Realize the correct commutation of the stator winding; secondly, realize the voltage regulation and speed regulation of the motor under the action of different PWM duty ratio control signals sent by the CPLD.

The current detection and comparison circuit and the voltage detection and comparison circuit feed back the collected current value and voltage value to the ADC acquisition terminal of ARM, and at the same time pass the current comparison value and voltage comparison value to the logic processor to judge overvoltage and overcurrent , when the circuit fails, the logic processor will take the lead in responding and quickly brake the motor, followed by the microprocessor, which will issue a brake command to control the motor brake again to ensure the fast fault protection of the motor.

Claims (2)

1. Dual-chip brushless DC motor drive control system, including host computer, drive circuit, voltage and current detection and comparison circuit and control system. The brushless DC motor has a built-in three-phase Hall sensor, and the drive circuit is a three-phase full-bridge circuit , characterized in that: the control system includes a logic processor connected to each other, a microprocessor, and a drive circuit connected to the logic processor; The logic processor includes a calculation unit, a protection unit, a drive control unit and a communication unit, wherein the calculation unit receives the feedback signal of the three-phase Hall sensor, and performs position calculation and speed calculation; the communication unit is used for communication with the microprocessor; The upper computer is connected with the microprocessor, and the upper computer transmits the control given value signal to the microprocessor, and controls the control mode of the microprocessor; The microprocessor receives the position and speed calculation values from the logic processor, combined with the given value of the host computer, uses the PID algorithm to calculate the control values of speed, position and torque, and feeds back the control values to the drive control unit of the logic processor , the logic processor is connected to the drive circuit through the drive circuit, the drive circuit receives the control value given by the drive control unit, and controls the operation of the brushless DC motor through the drive circuit; The voltage and current detection and comparison circuit includes a current detection and comparison circuit and a voltage detection and comparison circuit, both of which respectively feed back the collected current value and voltage value to the ADC acquisition terminal of the microprocessor, and simultaneously compare the current comparison value with the voltage comparison The value is passed to the logic processor, and the protection unit performs overvoltage and overcurrent judgments. 2. The dual-chip brushless DC motor drive control system according to claim 1, characterized in that: the logic processor adopts a CPLD chip, the microprocessor adopts an ARM chip, and the two communicate through the SPI bus.