2022-04-12
Under the high and low-temperature environment, the device characteristics and indicators of the permanent magnet motor system change greatly, the motor model and parameters are complex, the nonlinearity and coupling degree increase, and the power device loss changes greatly. Not only the loss analysis of the driver and the temperature rise control strategy are complex, but also four-quadrant operation control is more important, and the conventional drive controller design and motor system control strategy cannot meet the requirements of a high-temperature environment.
The conventionally designed drive controller works under relatively stable ambient temperature, and rarely considers indicators such as mass and volume. However, under extreme working conditions, the ambient temperature varies in a wide temperature range of -70 to 180 °C, and most powerful devices cannot be started at this low temperature, resulting in the failure of the driver function. In addition, limited by the total mass of the motor system, the heat dissipation performance of the drive controller must be greatly reduced, which in turn affects the performance and reliability of the drive controller.
Under ultra-high temperature conditions, mature SPWM, SVPWM, vector control methods, and other switching losses are large, and their applications are limited. With the development of control theory and all-digital control technology, various advanced algorithms such as speed feedforward, artificial intelligence, fuzzy control, neuron network, sliding mode variable structure control, and chaotic control are all available in modern permanent magnet motor servo control. successful application.
For the drive control system of a permanent magnet motor in a high-temperature environment, it is necessary to establish a motor-converter integrated model based on the physical field calculation, closely combine the characteristics of materials and devices, and conduct field-circuit coupling analysis to fully consider the environmental impact on the motor. The influence of system characteristics and the full use of modern control technology and intelligent control technology can improve the comprehensive control quality of the motor. In addition, permanent magnet motors working in harsh environments are not easy to replace and are under long-term operating conditions, and external environmental parameters (including temperature, pressure, airflow speed, direction, etc.) change complexly, resulting in motor system operating conditions follow-up. Therefore, it is necessary to study the design technology of high robustness drive controller of permanent magnet motor under the condition of parameter perturbation and external disturbance.