Speed Control of PMDC Motor using dsPIC Controller

Description

ABSTRACT

In this project, the speed control of the PMDC motor using dsPIC30F4011 was explained. The controller generates the PWM to drive the motor. The speed of the dc motor can be varied by changing the duty cycle of the PWM. The motor speed is monitored by using the proximity sensor placed in the motor.  Here Open-loop and closed-loop operations can be done. In Open-loop operation the speed of the motor is controlled manually. In closed-loop operation, the speed of the motor is controlled automatically with respect to the set speed. This development kit is used to design and develop controllers for PMDC. All the parts are separately available in the DIY market.

PMDC Motor Specifications

Power          :         25WATTS

Voltage       :         24VDC

Ampere       :         1.0A

RPM           :         1500RPM

Insulation    :         Class B

Block Diagram

In this project, the PMDC motor is controlled by dSPIC30F4011 DSP Processor. The stepdown transformer is used to convert 230V to 24VAC. This 24V AC is rectified and filtered to get DC voltage. This DC voltage is applied to the power circuit. The power circuit is designed using IRFP250 MOSFET. The controller is used to generate the PWM. This PWM is fed to the driver circuit. The driver circuit consists of TLP250 which is used for isolation and amplification of PWM. The driver output is fed to the power circuit for switching the power devices ON and OFF. The PMDC motor speed is varied by varying the duty cycle.

Terminal Identification

Proximity Sensor output RMC 

PWM Outputs

Motor Terminals

TLP 250 DRIVER BOARD SPECIFICATION

• 1 Nos Opto-Isolated Gate Drive
• Input Voltage 12V/AC/50Hz
• Output pulse Voltage: 15V
• Operating Frequency 25 kHz
• All input and outputs are terminated with RMC Male Connectors

TLP 250 DRIVER BOARD

DSPIC30F4011 Microcontroller Board

Key Function

1. SW1 = Open loop / Increment
2. SW2 = Closed loop / Decrement
3. SW3 = Enter

Feedback Block from Motor to Dspic30f4011