Performance evaluation of a hybrid electric brake system with a sliding mode controller
A new conceptual hybrid electric brake system (HEBS) that combines a contact conventional hydraulic brake system (CBS) and a contactless Eddy current brake (ECB) system is proposed in this paper. An ECB generates brake force from the interaction between an Eddy current and a magnetic flux. However, an ECB cannot generate sufficient torque at low vehicle speeds. Also, the system heats up as it operates, causing its performance to deteriorate. CBSs also have several problems related to friction, such as heat dissipation, noise, and wear. To overcome these problems, a combined HEBS was designed and evaluated. A vehicle and tire model was developed, and brake torque analysis was performed using an approximate theoretical model. A sliding mode controller was also designed to provide wheel slip control during vehicle motion. The simulation results showed that the HEBS and the designed controller reduced the stopping distance with less electric energy consumption on dry asphalt and icy roads. The results also prove that ECB systems are effective supplementary retardation equipment, so that an ideal match of the complementary benefits of a CBS and an ECB will increase safety while reducing vehicle operating costs. (c) 2004 Elsevier Ltd. All rights reserved.
sliding mode control hybrid electric brake system (hebs) eddy current brake (ecb) conventional brake system (cbs) anti-lock brake system (abs)