In this note, we are going to know about the EV and HEV configuration based on power converters. Welcome to Poly Notes Hub, a leading destination for Diploma Engineering Notes.
Author Name: Arun Paul.
EV and HEV configuration based on power converters
A. EV configuration based on power converters
The electric vehicle (EV) configuration based on power converters typically includes the following components:
- Battery Pack: The primary energy source of the electric vehicle is the battery pack, which stores electrical energy.
- Power Inverter (DC/AC Converter): The power inverter plays a crucial role in the EV system. It converts the direct current (DC) from the battery into alternating current (AC) required by the electric motor. This conversion enables the motor to operate efficiently.
- Electric Motor: The electric motor is responsible for converting electrical energy into mechanical energy, which propels the vehicle. It receives the alternating current (AC) from the power inverter and transforms it into rotational motion.
The power flow of an electric car normally begins with the battery pack, which delivers electricity to the power inverter. The power inverter then converts the DC electricity to AC power, which is adequate for the electric motor. The motor uses this electrical energy to power the wheels, allowing the vehicle to move.
This design emphasises the importance of power converters, notably the power inverter, in converting and utilising electrical energy to propel the electric vehicle.
B. HEV configuration based on power converters
In a Hybrid Electric Vehicle (HEV), power converters are critical in controlling the power flow between the vehicle’s various components. The usual HEV configuration based on power converters consists of the following elements:
- Internal Combustion Engine (ICE): The ICE serves as the primary source of mechanical power in an HEV. It generates mechanical energy by burning fuel, which can be gasoline, diesel, or alternative fuels.
- Electric Motor/Generator: The electric motor/generator assists the internal combustion engine during acceleration, deceleration, and certain driving conditions. It can act as a motor to provide additional power to the wheels or as a generator to convert kinetic energy during braking into electrical energy for storage in the battery.
- Battery Pack: The battery pack stores electrical energy for use by the electric motor. It can also store energy generated during regenerative braking.
- Power Electronics: Power electronics in an HEV include several types of converters and controllers:
- DC/DC Converter: This converter manages the flow of electricity between the high-voltage traction battery and the low-voltage auxiliary battery, which powers various vehicle systems.
- DC/AC Inverter: Similar to the power inverter in EVs, this converter converts the DC power from the battery into AC power needed by the electric motor during propulsion.
- AC/DC Rectifier: In some HEV configurations, an AC/DC rectifier is used to convert AC power generated by the electric motor during regenerative braking into DC power for storage in the battery.
- Motor Controller: The motor controller manages the operation of the electric motor, controlling its speed, torque, and direction of rotation based on driver inputs and vehicle operating conditions.
The power flow in a HEV varies according on driving circumstances and vehicle design. During acceleration, both the internal combustion engine and the electric motor may supply power to push the vehicle. During deceleration, the electric motor can function as a generator, turning kinetic energy into electrical energy for storage in the battery. Power converters play an important role in controlling these fluctuating power flows and improving the hybrid system’s overall efficiency.
