Sizing the Drive System in Hybrid and Electrical Vehicles

In hybrid and electrical vehicles, sizing the drive system is a crucial step in ensuring optimal performance and efficiency. The drive system consists of various components, including the electric machine, internal combustion engine (ICE), power electronics, energy storage technology, and supporting subsystems. Properly sizing these components is essential for achieving the desired power and torque requirements, as well as ensuring compatibility and efficiency.

Fundamentals of Matching the Electric Machine and the Internal Combustion Engine (ICE)

The electric machine and the internal combustion engine (ICE) work together in hybrid vehicles to provide power and propulsion. Matching these two components involves considering their power and torque characteristics, as well as their efficiency and compatibility. The goal is to achieve a seamless transition between the electric and ICE power sources, maximizing overall efficiency and performance.

Sizing the Propulsion Motor

The propulsion motor is responsible for providing the primary power in electric and hybrid vehicles. Sizing the propulsion motor involves considering the power and torque requirements of the vehicle, as well as efficiency considerations and motor characteristics. The following steps outline the process of sizing the propulsion motor:

1. Determine the power and torque requirements of the vehicle
2. Select a motor with suitable power and torque ratings
3. Consider efficiency and motor characteristics
4. Calculate the motor size and type based on the selected motor

Sizing the Power Electronics

The power electronics in hybrid and electric vehicles are responsible for converting and controlling the electrical energy between the energy storage system and the propulsion motor. Sizing the power electronics involves considering the power conversion and control requirements, voltage and current ratings, efficiency considerations, and power electronics specifications. The following steps outline the process of sizing the power electronics:

1. Determine the power conversion and control requirements
2. Select power electronics with suitable voltage and current ratings
3. Consider efficiency and power electronics specifications
4. Calculate the size and type of power electronics based on the selected components

Selecting the Energy Storage Technology

The energy storage technology in hybrid and electric vehicles plays a crucial role in storing and delivering electrical energy. Selecting the appropriate energy storage technology involves considering the energy storage requirements, energy density and power density considerations, charging and discharging characteristics, and available technology options. The following steps outline the process of selecting the energy storage technology:

1. Determine the energy storage requirements of the vehicle
2. Consider energy density and power density requirements
3. Evaluate charging and discharging characteristics
4. Select the appropriate energy storage technology based on the requirements

Communications and Supporting Subsystems

Communications and supporting subsystems are essential components of the drive system in hybrid and electric vehicles. Communications involve the exchange of information between components, ensuring proper coordination and control. Supporting subsystems include cooling systems, thermal management, and other auxiliary systems that enhance the overall performance and efficiency of the drive system. Considerations for communications and supporting subsystems include integration, compatibility, and the advantages and disadvantages they bring to the system.

Conclusion

Sizing the drive system in hybrid and electric vehicles is a critical step in achieving optimal performance and efficiency. By properly matching the electric machine and the internal combustion engine, sizing the propulsion motor and power electronics, selecting the energy storage technology, and considering communications and supporting subsystems, engineers can design drive systems that meet the power and torque requirements while maximizing efficiency and performance.

Summary

Sizing the drive system in hybrid and electrical vehicles is crucial for achieving optimal performance and efficiency. It involves matching the electric machine and the internal combustion engine (ICE), sizing the propulsion motor, sizing the power electronics, selecting the energy storage technology, and considering communications and supporting subsystems. By following a step-by-step process and considering various factors such as power requirements, torque requirements, efficiency, and characteristics of the components, engineers can design drive systems that meet the desired specifications.

Analogy

Sizing the drive system in hybrid and electrical vehicles is like fitting the right pieces of a puzzle together. Each component, such as the electric machine, internal combustion engine, power electronics, and energy storage technology, has a specific role to play. By carefully selecting and sizing these components, engineers can ensure that they fit together seamlessly, resulting in a well-functioning and efficient drive system.