Generating Method Considering Magnetic Saturation of SRMG Using Parallel Switching Mechanism
A Switched Reluctance Motor and Generator (SRMG) has a simple double salient pole structure that uses reluctance torque and does not use a permanent magnet, making the unit price low. This kind of structure makes it mechanically tough, have outstanding output characteristics making it used as traction purpose. However the noise, vibration and torque ripple is bigger than other motors and because it does not have any magnetic flux in the rotor, it is not useful in regenerating.[[ In this paper, novel regenerating method with separate excitation driving technique is presented. It is different from the existing regenerating brake that uses the remnant flux on a separate excitation type by using a parallel switching base to redirect portion of the flux path to excitation and the rest to generation. The proposed method makes it able to use a larger portion in generating, there is no limitation in the excitation current in order to generate and the control of the output is simple. Because the proposed method is based on the parallel switching technique the number of switch per phase does increase. However in motor mode the division of current goes down making it easier to go in generating mode. The proposed method is generated upper 50% regenerating power rate more than general method. In order to prove the possibility, a simulation of flux flow using FEM is applied. The proposed method is also verified by experiment result.