Application of fuzzy logic in constant speed control of hydraulic retarder

Abstract

Hydraulic retarders are extensively used in commercial vehicles because of their advantages, such as their large braking torque and long continuous operating hours. In this article, the structure and working principles of hydraulic retarders are introduced, and their dynamic characteristics are analyzed. The theoretical model of a hydraulic retarder is then established based on the dynamic analysis of a vehicle driving downhill. The braking process that involves the hydraulic retarder is divided into three stages. Moreover, the filling ratio controller of the hydraulic retarder is designed by adopting fuzzy control theory to control the braking torque of the vehicle while driving downhill. The vehicle dynamic model and constant-speed control model were then established in the MATLAB/Simulink environment. The simulation results showed that the fuzzy logic controller designed in this study has good constant-torque control and anti-inference performances, which can accurately and immediately produce braking torque to satisfy the braking requirement, thereby enabling the vehicle to drive downhill at a constant speed. As a result, the control strategy designed in this article can lead to significant improvements toward a safe road transport.

A bi-level control framework with temperature rise inference and intelligent decision-making longitudinal control on downgrade hydrodynamic braking process

“…The heuristic rule-based or fuzzy PID-based strategy is the most often used method. A fuzzy control logic-based controller is designed for heavy-duty vehicles equipped with a hydrodynamic retarder, 6 which enables the vehicle to drive downhill at a constant speed. A parallel PID and fuzzy longitudinal control method were proposed, 2 and the constant speed braking accuracy was achieved in downgrade braking simulation.…”

Analysis of heat exchange in the powertrain of a road vehicle with a retarder

“…The design and principle of operation of hydraulic retarders/ intarders in the literature is quite well described [14,23,24]. Nevertheless, the development of new technologies affects the efficiency of these devices and their characteristics are being investigated by many researchers [18,26,35]. It is noted that they are mandatory in Europe for vehicles with a gross vehicle weight (GVW) of over 16 tones.…”

Braking characteristics integrating open working chamber model and hydraulic control system model in a hydrodynamic retarder

“…Lei et al. 10 established a theoretical model of a hydrodynamic retarder based on the dynamic analysis of vehicle driving downhill and adopted fuzzy control logic to control the braking torque of the vehicle with the proposed oil-charging ratio controller of hydrodynamic retarder. Zheng et al.…”

“…Lu and Cheng 9 presented the relationship profile between rotor rotational speeds and braking torques obtained from bench test of a hydrodynamic retarder and proposed a constant-speed control strategy by changing the control cycle, the initial oil-charging ratio, and the variation of oil-charging ratio in each control cycle. Lei et al 10 established a theoretical model of a hydrodynamic retarder based on the dynamic analysis of vehicle driving downhill and adopted fuzzy control logic to control the braking torque of the vehicle with the proposed oil-charging ratio controller of hydrodynamic retarder. Zheng et al 11 introduced a novel auxiliary braking system involving a water medium retarder for heavy-duty vehicles.…”