Virtual Clutch Controller for Clutch-to-Clutch Shifts in Planetary-Type Automatic Transmission

Abstract

It is known that the shift processes of the four types of clutch-to-clutch shifts can theoretically be divided into two phases which are torque phase and inertia phase, but the execution orders are different. Two virtual clutch controllers are designed with the same eight states which include all control processes for these shifts. An equivalent method is proposed so that AT can be controlled just like DCT by adopting the torque ratios of oncoming clutch and offgoing clutch of each gear. The powertrain system model and the shift controller are established on Matlab/Simulink platform. The clutch-to-clutch shift processes have been studied based on the virtual clutch controller by software-in-the-loop simulations. Some typical problems in the clutch-to-clutch shift control are discussed and several control methods are compared to solve these problems.

Optimizing Automatic Transmission Double-Transition Shift Process Based on Multi-Objective Genetic Algorithm

“…Double-transition shift (DTS) is a dual single-transition shift process, which requires multiple clutches (typically four) for precisely coordinated control. If any clutch is not precisely controlled, power interruption or conflict may happen, and the shift quality will deteriorate [5,6]. The DTS involving more clutch elements is more complicated than the STS of traditional transmission, which poses a higher challenge to the AT control system of heavy-duty mining trucks [7].…”

Optimal Clutch Pressure Control in Shifting Process of Automatic Transmission for Heavy-Duty Mining Trucks

“…In order to avoid power interruption, shift overlapping, and overheating of the clutch plate, caused by incoordination between on-coming and off-going clutches, some researchers have studied the clutch-to-clutch shifting process and divided it into four parts (preshift phase, torque phase, inertia phase, and postshift phase) [5][6][7]. Meng et al [8] analyzed the AT's electrohydraulic control system and proposed a two-degree-of-freedom PID control method to optimize the duty ratio of proportional solenoid valves for the speed difference of clutch discs following a preset trajectory.…”