Closed loop control of speed control with DC motor

Closed-loop control of a DC motor ensures that the motor speed tracks a desired reference.

Key Components of the Closed-Loop System

1. DC Motor

• Type: PMDC or separately excited DC motor
• Input: Armature voltage control

1. Speed Sensor

• Measures actual speed
• Types: Encoder, tachogenerator, Hall-effect sensor

1. Reference Speed (Setpoint)

• Desired speed input from user or control system

1. Error Calculator

• Error=ωref−ωactual\text{Error} = \omega_{\text{ref}} - \omega_{\text{actual}}Error=ωref​−ωactual​

1. Controller (PI or PID)

• Processes the error
• Outputs control signal (usually PWM duty cycle)

1. Chopper (PWM-Based Converter)

• Varies average voltage to motor based on controller output
• Typically implemented using a MOSFET + diode + PWM generator