Pneumatic Regulating Module of Regenerative Braking System in Electric Bus

The Regenerative Braking System (RBS), as an important energy-saving technology, can effectively improve the energy economy of the electric vehicle [1]. The introduction of the regenerative braking force requiring the pneumatic regulating module to control the friction braking force more precisely and quickly. Solenoid on/off valve (SV) is controlled discontinuously with long response time as well as frequent pressure fluctuation, so consider using proportional relay valve (PPV) instead of it. A typical braking and Anti-lock Brake System (ABS) control Hardware-In-Loop (HIL) test was conducted with two kinds of pneumatic regulating modules. The test results shown that the PPV has more advantages in application of RBS.