This product is a controller used in 10m-long new energy passenger coach and converts DC power of the batteries of the electric motor car to AC power, to drive the motor. It also controls the motor and constitutes an important part for running of the electric motor car. It adopts the design concepts of system conciseness, low noise, trace consumption, light weight, ergonomics, and functional aesthetics. By inheriting the design concept of reasonability and practicality, our goal is to solve the problem of control of electric motor car and achieve highly efficient integration of four functions, to reduce the burden of high efficiency integration of electric motor car and greatly improve efficiency of electric motor car. This four in one technique is an innovation in the industry. Main drive motor controller/inflation pump motor controller, steering pump motor controller/DC-AC.