The Motor Drive System Design Of Two-wheeled Self-balancing Electric Vehicle

In recent years, the automobile have become the main means of transportation in human life with the rapid development of automotive industry. With the continuous rapid increase in car ownership, the issues of energy, environment and transportation have been increasingly obvious, which have plagued people’s daily life. It requires the birth of clean energy vehicles. The two-wheeled self-balancing vehicle emerges as the times require,which has become a hot topic research because of its clean, light and convenient. The study on balanced car includes various aspects, whose core part is movement and balance. Due to the high control needs, it often uses imported motor, but it is too expensive to spread easily. The main purpose of this paper is to design a set of driving system for domestic motor. It reduces costs and realizes the self-balancing vehicle running and balance control.Firstly, it selects a permanent magnet synchronous motor by comparing the performance of the motor. Secondly, it is to analyze and build the motor model. It uses a way of coordinate transformation to realize the decoupling control. It improves the control performance, which is the equivalent of a DC motor. It uses the space vector pulse width modulation to control the motor. It uses linear Hall sensor as a rotor position detection element, and it uses the circuit of drift suppression to eliminate zero drift and improve accuracy. Processing the position signals with different methods according to different ranges using digital signal processor (DSP) solves arithmetic overflow and improves the accuracy of the position signal. Thirdly, it is the design of hardware, including a power supply circuit, a power module, sampling, protection circuits, etc.And the design of software program realizes running and balance controls. Finally, it sets up the experiment platform of system to test and analyze the experimental results.The experimental results show that the detection accuracy of the motor rotor position is improved effectively after taking linear hall sensors and the drift suppression circuit, and the two-wheeled self-balancing vehicle achieves controls of running and balance by space vector pulse width modulation control technology. It completes the purpose of the design about the motor drive system, which will help self-balancing vehicle popularize and use in daily life.