桥门式起重机最优调压节能仿真研究

为了实现起重机最优调压节能运行,针对起重机的恒转矩运行和变工况负载特性,基于异步电动机Γ型等效电路,将定子铜耗和铁耗看作是仅与定子电压有关的不变损耗,将转子铜耗看作是随负载转矩变化的可变损耗,得到电气总损耗与定子电压和负载转矩的直接关系。通过求解得出电动机稳定运行条件下使电气总损耗最小的最优电压。研究和仿真结果表明:定子电压和负载转矩共同影响总损耗,按照电动机稳定运行时的近似转差率得出总损耗的精确解和近似解在低于200V时,误差较大,在高于200V时误差几乎为零,而随负载转矩变化的最优电压误差不超过7V;起重机按照负载转矩变化的适时调压运行方式的节能效果是显著的。

Research and Simulation on Energy Saving of Optimal Regulation Voltage for Overhead and Gantry Crane

In order to realize container crane’s saving energy operation of optimal voltage regulation,aiming at crane’s working characteristics of the constant torque operation mode and the load under variable working conditions,the direct relationship between electric total loss and stator voltage or load torque was obtained based on the asynchronous motor’s Γ-shape equivalent circuit,because the stator’s copper loss and iron loss were regarded as invariable loss that only relates to stator voltage,and the rotor’s copper loss was regarded as variable loss that changed with load torque’s changing.The optimal regulation voltage was obtained through mathematical calculation on the condition that the asynchronous motor wae stablely running.The electric total loss was minimum when the stator’s voltage was the optimal regulation voltage.The research and simulation results showed that the electric total loss was commonly influenced by the stator voltage and load torque;while the asynchronous motor ran stablely,the electric total loss’s error between the exact solution and the approximate solution obtained according to the approximate slip ratio was bigger when the stator voltage was less than 200V,and the error was nearly zero when the stator voltage was more than 200V,but the optimal voltage error was not more than 7V.The crane’s effect of energy saving is prominent with optimal voltage regulation mode according to the load torque’s changing.