Research on the influence of the proportional relay valve on the economy and safety of the electric bus through the braking energy recovery system

ABSTRACT

To research the influence of the proportional relay valve on the economy and safety of the electric bus through the braking recovery system, a proportional relay valve model was proposed. Based on the analysis of the structure and working principle of the solenoid on/off valve, a dynamic model of “electro-magnetic-machine-air” coupling was simulated and analyzed. Then, based on the solenoid on/off valve and proportional relay valve, two pressure regulator modules were designed, the braking energy recovery system schemes were designed, respectively. Fuel economy tests were carried out under China city bus typical driving cycle based on two kinds of air pressure regulating module to research the influence of the proportional relay valve on the economy of the electric bus. An integrated control system of braking energy recovery and anti-lock braking system based on the proportional relay valve was proposed, hardware-in-the-loop braking energy recovery system contrast tests of the anti-lock braking system were also carried out based on two kinds of air pressure regulating module.

The test results indicated that the proposed braking energy recovery system schemes were effective. The test results also demonstrated the economic contribution rate of the braking energy recovery of the proportional relay valve pneumatic control module was slightly higher than that of the proportional relay valve. Meanwhile, the proportion relay valve pressure regulating module achieved a good target speed follow and the accurate adjustment of air pressure in anti-lock braking system control.

KEYWORDS:

• Braking energy recovery system
• proportional relay valve
• solenoid on/off valve
• the economic contribution rate
• hardware-in-the-loop test
• anti-lock braking system

Additional information

Funding

The authors would like to thank the National Key Research and Development Plan of China [Project No. 2016YFB0101402] for funding this work.

Notes on contributors

Ning Li

Ning Li is pursuing a Ph.D. degree in mechanical engineering from Beijing University of Technology, Beijing, China. She is currently studying at State Key Laboratory of Automotive Safety and Energy, Tsinghua University, China. Her research direction is energy management of electric vehicles.

Chengkun He

Chengkun He received his Ph.D. degrees from the Institute of Electrical Engineering of Chinese Academy of Sciences, China. He is currently working at State Key Laboratory of Automotive Safety and Energy, Tsinghua University, China. His research interests include autonomous vehicle test and load emulator design.

Junzhi Zhang

Junzhi Zhang received his B.S., M.S., and Ph.D. degrees from Jilin University, China. He is currently a Professor at State Key Laboratory of Automotive Safety and Energy, Tsinghua University, China. His research interests include regenerative braking, hybrid vehicle powertrain, energy management, autonomous vehicle test, and load emulator design.

Yingshuai Liu

Yingshuai Liu received his Ph.D. degrees from Beijing University of Technology, Beijing, China. He is currently working at College of Electrical Automation, Weifang University of Science and Technology, Weifang, China. His research interests include aftertreatment of internal combustion engine emission, new energy technology of electric vehicle.

Cheng Lin

Cheng Lin received the B.S. degree in automotive engineering from the Jilin University in 2015. He is pursuing a Ph.D. degree in power engineering and engineering thermophysics from Tsinghua University, Beijing, China. His research interest includes vehicle dynamics, nonlinear control, and adaptive control theory.

Chao Li

Chao Li, born in 1968, doctor, Professor, doctoral supervisor. The main research direction is electric vehicle dynamics control.