Simulation And Research Of Hybrid Power Crane System Based On AC Drives

With the problems of energy shortage and environment pollution have become more serious, all businesses compete for research and development of energy conservation and environmental protection products. The driven scheme consist with diesel, hydraulic system and multiply actuators which used by the lifting machinery industry has the disadvantages of high oil consumption and bad emission quality, and, there is not a reasonable and fully utilization for its recovered energy generated during the frequently starting and braking process. Therefore, the energy conservation of lifting machinery becomes the industry's attention. After the hybrid system was applied in automotive industry successfully, it is widely used in the lifting machinery industry, especially the rapid development of frequency converter technique and energy storage devices make its application prospect more and more widely.One of the most used hybrid driver method in the lifting machinery industry is the combination power supply of super capacitor and diesel generator. This paper describes the advantage of the hybrid system based on the principle, characteristics of super capacitor and working characteristics of AC frequency conversion crane; details composition of the system structure; establishes its simulation models with the Saber toolbox; and conducts analysis for the system.This paper researches the principles, types and topological structure of barrierless bidirectional DC/DC converter, and designs control strategy consists of constant power mode and constant voltage mode to control the discharge and charge of super capacitor. Finally establishes the simulation models for the control circuit.This paper also describes the development of frequency converter technique, introduces the types and principles of frequency converter system, emphatically researches the hardware structure and control technique of VVVF inverter, and conducts the simulation research for vector control frequency converter system.This paper establishes a simulation based on hybrid power system for AC frequency conversion crane with Saber toolbox, simulates the discharge of super capacitor under the condition of engine idling, charge of super capacitor when dropping the cargo, and power supply of diesel generator combines with super capacitor.