电液混合驱动大惯量回转系统特性与能效分析

为了解决大惯量回转系统频繁启动和制动作业导致节流损失大和制动动能浪费严重的问题,提出一种电气和液压混合驱动大惯量回转系统。系统采用永磁同步电机作为主动力源,控制回转系统运动;由蓄能器提供动力的液压马达作为辅助动力源,为电机启动加速提供扭矩补偿,蓄能器高效回收制动动能再利用。建立多学科联合仿真系统模型,基于主辅动力源合理供给原则,设计全周期工况识别速度控制策略,搭建电液混合驱动回转试验平台,对回转系统的特性和能效进行分析。研究结果表明,电液混合驱动大惯量回转系统,随着转速和转动惯量的变化,回转制动动能回收效率为40.5%～65.9%。相同工况下,与纯电机驱动系统相比,电液混合驱动系统启动加速时间减小1.2 s,制动动能回收效率为63.5%,降低系统能耗40.8%,使回转系统更加平稳地运行。

Characteristics and Energy Efficiency Analysis of Electro-hydraulic Hybrid Drive Large Inertia Swing System

With the shortage of fossil energy and environmental pollution becoming more and more serious, it is urgent to study the energy saving and emission reduction technology of construction machinery with large quantity and high energy consumption. In common construction machinery, such as excavators, cranes and hoists, there are large inertia hydraulic swing systems with frequently start and brake operations. During the braking of large inertia hydraulic swing system, the braking kinetic energy is converted into heat energy through the throttling effect of the valve port, resulting in a large amount of energy loss. If the braking kinetic energy of the swing system can be recycled and reused, it can not only reduce the energy consumption of the system and the cost of construction machinery, but also save energy and protect the environment. Therefore, an electrical and hydraulic hybrid drive large inertia swing system was proposed. In the system, as the main power source, the permanent magnet synchronous motor was used to control the movement of the swing system. The hydraulic motor, powered by the accumulator, was used as an auxiliary power source to provide torque compensation for the acceleration of the motor start-up, and the accumulator efficiently recovered the braking kinetic energy for reuse. In the research, a multidisciplinary joint simulation system model was established. Based on the principle of reasonable supply control of main and auxiliary power sources, a full-cycle condition recognition speed control strategy was designed. An electro-hydraulic hybrid drive swing test platform was built to analyze the characteristics and energy efficiency of the swing system. The results showed that the energy recovery efficiency of swing braking was 40.5%~65.9% with the change of rotational speed and rotational inertia. Compared with the pure motor drive system, the electro hydraulic hybrid drive system had a faster start-up acceleration of 1.2s, which can achieve a braking kinetic energy recovery efficiency of 63.5%, reduce system energy consumption by 40.8%, and make the swing system run more smoothly.