基于隔离度的增程式电动汽车辅助动力单元抗干扰特性研究

摘要

为研究增程式电动汽车辅助动力单元APU的抗干扰特性,分析了车载环境下APU的干扰转矩特征,建立了APU面向控制的转速-转矩控制模型,实现了APU转速、转矩控制的解耦;采用BP-PID实现了APU转速自适应控制,并通过仿真测试了APU恒转速-变转矩模型和恒转矩-变转速模型下的转速、转矩跟随性能;通过隔离度性能指标,量化了APU干扰转矩和转速波动的关系.仿真测试表明,设计的APU控制系统对50 N·m、100 Hz的正弦干扰转矩的最大隔离度为16.09%,对标准差为50 N·m、100 Hz的带限白噪声的最大隔离度为51.52%,并分析了两者隔离度性能指标的不同及原因.同时,通过隔离度指标可以对APU控制系统的抗干扰性能进行分析和设计.%In order to study the anti-disturbance characteristics of auxiliary power unit (APU)of extended-range electric vehicle (EREV),following contents are discussed.The characteristics of disturbance torque of APU in the EREV are ana-lyzed.The control-oriented model of APU is setup,which can decouple the speed and torque control.BP-PID controller is used to realize the speed adaptive control of APU.Simulations are used to test the tracking performances of constant speed variable torque control mode and constant torque variable speed control mode.The isolation degree (ID)index qualifies the relationship between the disturbance torque and speed fluctuation.Simulation results show that the maximum ID of the designed control system under the sine disturbance of 50 N·m magnitude and 100 Hz frequency is 16.09% and the maximum ID of the de-signed control system under the band-limited white noise of 50 N · m standard deviation magnitude and 100 Hz frequency is 51.52%.The ID index difference of the APU control system between the two disturbance torque types is analyzed and the reasons are discussed.Furthermore,The ID index can be used to analyze and design anti-disturbance characteristic of APU.