Research On Electric Glof Vehicle's Separately Excited DC Motor Drive System

In order to maintain a beautiful and elegant environment of the golf field, the vehicle used there should have zero pollution and low noise. Meanwhile, the golf vehicle reduces the request of the automobile dynamic quality and travel mileage. Electric Vehicle (EV) becomes a kind of new, fast-developing vehicle in the last years, which has the best future as a green vehicle, as the problems of energy and environment are becoming more and more serious in the 21st century. In this case use of pure electric vehicle as the golf vehicle suite extremely.The drive system is the core part of the electric golf vehicle's power system, which is also the major work that has been completed by this thesis. The thesis takes the overall plan design to the separately excited DC motor's drive system, and carries on the simulation analysis to this drive system by SABER software, so that to confirm it can realize the motor's functions such as speed regulation, energy regeneration as well as soft-switching.For the part of hardware design, the master control chip adopts dsPIC30F4011 of Microchip Company, which is especially designed for motor control. The power module adopts the multi-MOSFET-parallel scheme instead of IPM module, which performance well but rather expensive. In this way, the cost is saved very much. This is the challenging part of this design, and also is the origination in the domestic project application. The heat dissipation mode and heat dissipation material of the drive system also carries on thorough consideration. The power dissipation of the multi-MOSFET-parallel is calculated in this thesis. So that it can instruct the choice of the heat dissipation mode and verify its rationality, the long-term movement experiments prove this cooling system can achieve the ideal effect. The hardware design also includes the accelerator presentation, voltage and current inspection, CAN communication, over current protection, etc.The software of drive system can realize the function of motor speed adjustment according to the accelerator, and the function of motor's positive and reverse rotation. In order to observe the motor running status, the CAN communication routine and LCD display routine based on the LCD meter has been completed.The development process of the motor drive module is introduced in this thesis. According to the wave profiles get from the oscilloscope, the running statuses of the driven model are analyzed in this thesis. Meanwhile, this thesis discusses the parallel capacity and non-inductive capacity's protection function to MOSFET.The separately excited DC motor drive system works very well on the electric golf vehicle. The advantages are structure simple, performance reliable and cost litter. It makes the price of the electric golf vehicle lower to the public can accept, so that helps to the popularization of EV.