In some industrial applications, cage asynchronous motors usually run with a continuous inter-conversion of generator and motor modes. In order to study the loss and reactive power characteristics under those complex conditions, taking a 5. 5 kW motor as an example, the experimental scheme to simulate the generator and motor modes was designed, the stator and rotor copper loss, fundamental iron loss, excess loss and reactive power were systematically tested and analyzed with load torque variation. In addition, considering that the stator current can be measured easily on field, it also further concluded the general rules of the above loss term varying with stator current. The results showed that, with the same stator current, fundamental iron loss, excess loss and reactive power in generator mode were more than the ones in motor modes, under rated stator current condition, the total losses and reactive power in the generator mode are 9% and 20% over than the ones in the motor mode respectively.%在某些工业生产场合,笼型异步电机通常连续运行在电动和发电相互转换的工况,为了研究在此类复杂工况下电机损耗和无功特性,以一台5.5 kW异步电机为例,设计了能够模拟电动和发电工况的试验方案,系统测试并分析得出电机内部定转子铜耗、基本铁耗、附加损耗及无功需求随负载转矩的变化规律.此外,考虑到定子电流在实际生产中易测量,进一步分析了上述各项损耗随定子电流变化的一般规律.结果显示,定子电流相同时,发电工况的基本铁耗、附加损耗,以及无功需求均大于电动工况,额定电流的发电工况下电机总损耗和无功需求比电动工况分别高约9％和20％.
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