The project is used to design a system which controls the speed of a DC motor using an efficient method of PWM through IR communication.

 Here in this project we use the PWM technique to control the speed of the motor. The average voltage supplied to the load should be varied to obtain different speeds, which can be achieved by setting an appropriate duty cycle. The term duty cycle describes the proportion of ‘on’ time to the regular interval or ‘period’ of time. A low duty cycle corresponds to low power, because the power is off for most of the time. Duty cycle is expressed in percent, 100% being fully on. The main advantage of PWM is that power loss in the switching devices is very low. When a switch is off there is practically no current, and when it is on, there is almost no voltage drop across the switch. Power loss, being the product of voltage and current, is thus in both cases close to zero. PWM also works well with digital controls, which, because of their on/off nature, can easily set the needed duty cycle. Rotating the motor anticlockwise or clockwise, or increasing or decreasing the speed of the motor can be done easily with an IR remote without actually going near the motor switches and operating them manually. The manual operation of the motor is completely avoided in this project.

IR remote acts as the transmitter in this project. When a button is pressed in the remote, the signal will be passed and received by the TSOP Receiver. This signal is sent to the microcontroller which decodes the signal and performs the corresponding action in accordance with the button pressed in the remote. For example, if number 1 is pressed in the remote, the motor has to rotate anticlockwise direction. The other tasks will be performed in the similar fashion using IR. 16X2 LCD is connected at the receiver end to display the speed level of the motor and the direction.

This project uses regulated 5V, 500mA & 12V, 500mA power supply. 7805 and 7812 three terminal voltage regulators are used for voltage regulation. Full wave bridge rectifier is used to rectify the AC output of secondary of 230/12V step down transformer.

TECHNICAL SPECIFICATIONS:

HARDWARE:

Micro controller         :           AT89x series

Crystal                        :           11.0592 MHz

LCD                            :           HD44780

DC motor                    :

Driver IC                     :           L293D

IR receiver                  :           TSOP 1738

IR transmitter             :           Remote

Power supply

Transformer                :           12V step down 

Filter                           :           1000uf/25V

Voltage Regulator      :           7805

SOFTWARE:

Keil micro vision

Proteus

UC flash

APPLICATIONS:

• AC motor drives
• Spinning mills
• Industrial applications