Abstract
This article describes a newly developed electro-thermal-mechanical coupled simulation for HV inverters, a modeling technique for fast and accurate calculation, simulation results and their verification. The simulation is based on an electric circuit simulation technique and is obtained by modeling a motor, motor controller, power semiconductor devices and their driver circuits, interconnection, smoothing capacitors, and thermal circuits of power semiconductors including package structure. The current, voltage, and carrier frequency data computed from the control model containing many dynamic characteristics of motor and vehicle specifications as driving patterns were inputted into the inverter circuit. Using this modeling technique, a five-second full-throttle simulation was carried out in sixteen hours of computation time. This inverter system model enables simulations with various characteristics from all inverter components, such as the controller, power semiconductor devices, module design, cooling structure and driver circuits. The error in the simulation is within five percent. This technique enables not only simulation of single components but also of the mutual impact among several components in a system. As a result, the inverter design can be optimized, thus contributing to significant improvements in the acceleration performance of HVs.
Keywords:simulation, hybrid vehicle, acceleration performance, optimum design, inverter