Simulating EV Dynamics — Lesson 3

This lesson covers the simulation of dynamic equations with variable tractive effort in electric vehicles. It delves into the three modes of operation of an electric vehicle: constant torque region, constant power region, and constant speed region. The lesson explains how these modes are divided based on the speed of the vehicle and how torque and power vary in each region. It also discusses how to calculate performance parameters like time, average power, and energy required in each region. The lesson further explores how to simulate these calculations using MATLAB and how to analyze the performance of the vehicle under different conditions such as varying mass and slope. Finally, it introduces the concept of driving cycles and range calculation in electric vehicles.

Video Highlights

01:52 - Variation of torque and power in three electric vehicle operation modes
06:09 - Calculation of performance parameters in each mode
08:22 - Performance parameter simulation using MATLAB
10:38 - Vehicle performance analysis under various conditions
14:51 - MATLAB simulation demonstration for plotting torque, velocity, and distance over time
32:16 - Performance analysis discussion for conditions such as slope driving or vehicle mass reduction
42:59 - Introduction to driving cycles and range calculation in electric vehicles
54:22 - Algorithm explanation for range calculation

Key Takeaways

- Electric vehicles operate in three modes: constant torque region, constant power region, and constant speed region. These modes are divided based on the speed of the vehicle.
- The torque and power vary in each mode. In the constant torque region, torque is constant and power varies directly with velocity. In the constant power region, power is constant and torque varies inversely with velocity. In the constant speed region, there is no acceleration and the torque requirement is only to support the resistive forces.
- Performance parameters like time, average power, and energy required in each mode can be calculated and simulated using MATLAB.
- The performance of the vehicle can be analyzed under different conditions such as varying mass and slope.
- Driving cycles and range calculation are important aspects of electric vehicles. Different regulation agencies have defined standard drive profiles for this purpose.