This project is used to control the speed of three phase induction motor by using three phase inverter. The dc voltage is applied to the three phase inverter. This three phase VSI operates at 120 degree mode of operation. Three phase induction motor speed depends on the frequency of inverter. The frequency is varied by using switches of the DSP controller.
This project is mainly used for control the speed of induction motor. Induction motor speed can be controlled by using changing the frequency of the inverter. This motor control can be done by TMS320F2812 DSP Controller. This controller is used to generate the PWM pulses.
The dc voltage is applied to the three phase inverter circuit. It converts the dc voltage into three phase ac voltage to drive the three phase induction motor. The TMS320F2812 DSP controller has key function for controlling the speed of the induction motor. The F2812 controller has two functions. They are
Block Diagram Explanation
- Pulse generator: - Here we have used TMS320F2812 DSP Controller to generate PWM signal.
- Driver circuit: It is used to amplify the pulses and provided isolations using opto coupler. It has two functions,
- Bridge Rectifier: It converts AC supply to DC Supply.
- Three Phase Inverter: It converts DC supply tothree phase AC Supply to drive the three phase induction motor.
TMS320F2812 DSP Controller Board
The TMS320F2812 DSP Controller is used to generate the PWM pulses for three phase inverter circuit. The TMS320F2812 DSP Controller pulses are given to the driver circuit as input. Driver board is mainly used to isolate and amplify the input signals from the controller. The amplified driver output is connected to the main power circuit devices. The ac supply is converted into dc by using bridge rectifier. And the dc voltage is applied to three phase inverter circuit and by varying the frequency of the inverter the motor speed also varied.
Circuit Diagram for Three Phase Inverter
- High efficiency
- Easy to control the speed
- Switching losses are reduced
- Industrial applications
- Pumping system
The speed control of three phase induction motor can be controlled by using TMS320F2812 DSP Controller. The motor will be runs at different speed by varying the frequency of the inverter circuit. This project is also possible for speed monitoring by using proximity sensor.
Three Phase Inverter Pattern
Pulse Comparison Waveform
Phase to phase Output Waveform