Research On Automotive Electromechanical Brake Control System Based On FPGA/SOPC Technology

With the gradual development of the automobile industry, people are more concerned on car's safety, comfort, environmental protection, aesthetics, etc. While the car's security is one of the most valued. Because of by adding a large number of electronic control system in traditional hydraulic or air brake system, such as ABS, TCS, ESP, etc. The structures and piping layout increasingly become complex and the leakage hidden dangers of hydraulic circuit have also increased. At the same time the difficulty of assembly and maintenance brought about an increase. Therefore, the structure is relatively simple, functional integration and reliable electro-mechanical braking systems become increasingly popular. As the EMB small size, fast response, reliable performance advantages, making ABS and other active safety systems can easily achieve and the other control of centralized management and sharing of information through the CAN bus.First, through research and analysis of existing electro-mechanical braking system of the principles and institutions at home and abroad in this paper, combined with Jiangsu University school of self-designed car EMB structure. We have researched the methods and strategies anti-lock braking system and motor control on the electro-mechanical control. In order to compare the correctness of the EMB control system strategies, the dynamics control model of electro-mechanical system is created in the Matlab/Simulink and is used different control algorithms to analysis the simulation of ABS and motor control strategies. Finally, we determine to use the fuzzy PI control algorithm in this article. Second, with the structural characteristics of EMB, vehicle braking force which is provided by hydraulic have translated into brushless DC torque motor. Focusing on the characteristics of brushless DC motor ,we have designed the hardware structure of EMB system based on FPGA / SOPC technology and have detailed divided the internal structure of EMB central control unit and motor controller. Then, for the PWM control method used in EMB motor, we have written the logic of the motor control program in the Quartus II and the simulation results show the correctness and rationality of the process.Finally, with existing laboratory equipment and development tools, we have designed a set of experimental program based on EDA / SOPC system development platform and the brake pedal. Using SOPC technology and with NIOS II + DSP Builder to achieve the control of brushless DC torque motor. We can achieve the design of the external digital circuit and the PWM control of motor through NIOS II and can achieve fuzzy PI algorithm of brushless DC motor by DSP Builder. Finally, we achieve the overall control function with the organic combination of the two sections. To study the relationship between the brake unit which produce intent and the torque output of brushless DC motor .It is demonstrated the correctness of control methods and the FPGA/SOPC's superiority in the vehicle electro-mechanical brake system control field.