Speed Control Of DC Motor

Speed Control Of Dc Motor is developed to control any speed of DC motor using 555 & Mosfet. A PWM circuit based on timer NE555 is the heart of this Speed Control Of Dc Motor. NE555 is wired as an astable multivibrator whose duty cycle can be adjusted by varying the POT VR1. The output of IC1 is coupled to the base of transistor Q1 which drives the motor according to the PWM signal available at its base. Higher the duty cycle the average voltage across motor will be high which results in higher motor speed and vice versa. The following project is a PWM motor control. It is very easy to be built and it can efficiently control all DCmotor to rpm as low as 450 rpm . It uses ONLY one 555 timer and a few other components, and it can be powered also directly from the PC power supply, from the 12 Volts line. DC Motor Speed Controller Circuit Using NE555 PWM switching will create a series of PWM pulses and will be driven directly to the gate of the MOSFET. The MOSFET is chosen to be big enough to carry enough loads, up to 9.2 amperes. You can choose a MOSFET according to your needs. The MOSFET will generate enough power so that the motor will start revolving. The capacitor across the MOSFET is the solution to the 'kicking sound'. The MOSFET will send to the motor pulses according to the pulses generated from the 555. If you remove the capacitor, you will definitely hear this annoying sound. The capacitor will smooth the voltage across the motor and therefore the power driven to it will be smooth, avoiding the torque kick.