Electrichydraulic composite braking coordinated controlbased on system efficiency optimization(PDF)
长安大学学报（自然科学版）[ISSN:1006-6977/CN:61-1281/TN]
- Issue:
- 2020年3期
- Page:
- 117-126
- Research Field:
- 汽车与机械工程
- Publishing date:
Info
- Title:
- Electrichydraulic composite braking coordinated controlbased on system efficiency optimization
- Author(s):
- YANG Yang1; 2; CHEN Jing2; LUO Chang2; TANG Qingsong2
- (1. State Key Laboratory of Mechanical Transmission, Chongqing University, Chongqing 400044, China;2. School of Automotive Engineering, Chongqing University, Chongqing 400044, China)
- Keywords:
- automobile engineering; electrohydraulic compound braking; coordinated control; HEV; efficiency optimization
- PACS:
- -
- DOI:
- -
- Abstract:
- In order to improve the coordination performance and braking energy recovery efficiency of electrichydraulic composite braking system of hybrid electric vehicle, a new type of plugin hybrid electric vehicle (PHEV) with dualmotor was taken as the research object. Aimed at the difference dynamic characteristics of the motor braking system and the hydraulic braking system, the braking force distribution strategy and coordinated control strategy based on the coupling characteristics were brought out. The motor loss model was built to achieve maximum use of the regenerative braking force on the premise of ensuring the braking safety, and combined the hydraulic brake system model which can dynamically control pressure to accurately simulate the actual electrichydraulic composite braking system working characteristic. By controlling the motor current, the loss can be minimized. And the optimization of motorcontinuously variable transmission (CVT) joint efficiency was achieved by ratio control. The wheel cylinder pressure of the hydraulic braking system can be controlled through the high speed switch valve by the PID control. The realtime optimal allocation strategy based on threshold method and coordinated control strategy based on braking strength correction were developed. Vehicle dynamics models of motor, hydraulic brake system and transmission in MATLAB/SimulinkAMESim was established, and the strategy was verified by cosimulation experiments of continuous braking strength and sudden braking strength. The results show that the control strategy can take the advantages of dualmotor braking recovery system, increase braking energy recovery rate, improve the braking safety and ride comfort of the vehicle effectively, and reduce braking force fluctuation. When initial velocity is 60 km/h and the braking strength is changed from 0.6 to 0.3, the jerk from 93.36 drops up to 17.52 m/s3, which satisfies the requirement of ride comfort. And the maximum actual energy recovery power can be increased by 0.32 kW under UDDS cycle conditions. 4 tabs, 13 figs, 24 refs.
Last Update: 2020-06-03