A Method of Starting Performance Calculation Based on Lock Test for Linear Induction Motor.

The equivalent circuit of the linear induction motor (LIM) is generally expressed as the same that of the rotating induction motor (IM). Then, the starting performance of the LIM is obtained using results of the no-load test and the lock test similar with the IM.However, it is almost impossible to perform the no-load test for the LIM in the factory, because it needs a special equipment to move the mover at synchronous speed. Therefore, a new method is required to calculate the performance of the LIM by simple tests without the no-load test.In this paper, we propose a new method which does not need the no-load test for the starting performance calculation of the LIM. At first, the results of the no-load test and the lock test for the test machine are shown. And an equivalent circuit which is suitable for the performance calculation of the LIM is proposed. Moreover, a method of determining its constants from results of the lock test is discussed.The starting performance calculation for the LIM was made using the proposed equivalent circuit. The calculated results for the thrust vs. speed, the current vs. speed and the power input vs. slip characteristics were satisfactorily agreed with experimental results.