ENERGY-SAVING SYSTEM APPLYING PRESSURE ACCUMULATORS FOR VVVF CONTROLLED HYDRAULIC ELEVATORS

摘要

In order to improve the energy utilization efficiency of hydraulic elevators, an innovative energy-saving controlled system applying pressure accumulators in hydraulic elevators was brought forward in this paper. Firstly the working principle of the system was discussed and analyzed under different working status. Then the mathematical models of the system were established. Numerical simulations for the static and dynamic of the system were studied on the Simulink environment of MATLAB kits. Experiments on the upward and downward movement of elevator were done under different typical working conditions. Numerical simulations coincided with experimental results in general. Compared with other type hydraulic elevator systems, such as conventional valve controlled system, inverter controlled system, the system with pressure accumulators has the highest energy-saving efficiency. In summary, the innovative energy-saving system which runs steadily and comfortably, saves energy remarkably, has good potential for application in not only hydraulic elevators but also in other vertically reciprocating mechanical systems.