The Study On Electric Vehicle Central Controller Based On CAN-bus

Considered the pollution and resource problems caused by vehicle industry, electric vehicles appeal to more and more attentions for their benefits of environment protection and low resource consumption. Numbers of companies, universities and research institutes have devoted themselves to the research and promotion of electric vehicles. Compared with the simple structured electric vehicles which only use motors to replace engines and preserve mechanical transmission devices, in-wheel electric vehicles have technical superiority. The goal of this issue is to establish an electric vehicle using in-wheel motors.First of all, we establish the network architecture of the system, because network is the base of the system, and all control instructions are accomplished via network. CAN-BUS is a field bus designed just for automotive electronics. In this issue, we use CAN-BUS to realize the communications between the EV central controller and two in-wheel motor controllers. Based on the CANOPEN protocols, we set up the high level protocol for EV.Second, we brought out a differential algorithm for steering electric vehicles. Considered the characteristics of the in-wheel electric vehicle, we need to invent a differential algorithm for the steering conditions. Analyzed the dynamic parameters of the steering electric vehicles, this issue presents a closed loop control algorithm of two driven tyres ratios to realize the goal of control.In the last, we present the hardware and software design of the EV control system. Hardware includes a flyback DC/DC converter which is used to supply energy to the system, and a central controller. We finished the design and debug of hardware, then we coded on MCU of the central controller, to accomplish the software design. The program running on the MCU achieved the control target of the system.