Three-phase Pulse Width Modulated AC/DC Rectifier and DC/AC Inverter

Electric vehicles use inverter and rectifier circuits in order to convert power from one type to another. They run on direct current batteries, but their motors can run on direct current (DC) or alternating current (AC). There is a need for both of these circuits if the motor runs on AC. The objective of this project is to successfully replicate driving and braking in an electric vehicle, and understand its power flow. Both systems should start to convert the input power as soon as the source is “on” and should continue this conversion without interruption. In the driving system, a DC power supply will be the source and the inverter should convert that to three-phase alternating AC power to spin a three-phase AC induction motor, which should continue to spin. Sinusoidal pulse width modulation will be the technique used to control the MOSFETs in the inverter circuit. The three-phase AC signals should be 50Hz and 120 degrees phase shifted from one another. This induction motor should then be coupled to a DC machine and computer to control torque. In the braking system, the AC permanent magnet motor should be spun by the DC machine, which is controlled by the computer. This three-phase AC voltage should then be converted to DC voltage through the rectifier circuit to power a power resistor. The results of this project include a successful driving system without the DC machine and computer combination to control torque, and a semi-successful braking system. The braking system needs real-time inputs that can be compared in the Arduino microcontroller, which requires the use of other components not mentioned in this report. The AC induction motor started spinning as soon as power was provided and continued without interruption. The frequency of each three-phase AC signal was 50Hz and they were 120 degrees phase shifted from each other