Real-Time Test System for Electro-Hydraulic Proportional Control Loop of Automatic Transmission

Abstract

In order to test and evaluate the automatic transmission (AT) electronic control system and improve the development efficiency with lower cost, a hardware-in-loop simulation (HILS) platform of AT electronic control system is built. To simulate the electro-hydraulic proportional control loop and test the control signals output from the TCU, a real-time test system for electro-hydraulic proportional control in HILS is synchronously designed. First, the AT electro-hydraulic proportional control loop is anatomized and modeled. Second, to accelerate the calculation of models in microcontrollers, the floating point arithmetic is turned into integer type fixed-point arithmetic. Third, the hardware and the software with dual-core framework of the real-time test system are designed. Fourth, the HILS platform of AT electronic control system, including the real-time test system for electro-hydraulic proportional control, is built. Finally, steady state tests, transient tests and buffer control tests are conducted. The results verify the function of real-time test system for electro-hydraulic proportional control. The real-time test system basically meets the design demands and lays a foundation for HILS platform.