The Research On Electric Inertia Simu-lation Based On Dual-stator Motor

Normally, rotating machinery such as speed control system, position servo systemetc. needs to be tested for its transmission performance when it is designed and manu-factured. The testing process generally includes two areas, loading test and mechanicalinertia test. Load simulator is often applied to execute the test, by simulating the loadtorque and the corresponding inertia to the tested machines. The tests are aimed to im-prove the tested machines, raise the success rate of reliability, reduce R&D cycle andsave cost. This dissertation conducts a research on inertia simulation applied to loadsimulator and mainly studies about how to apply electric inertia simulation to electricalload simulator.Mechanical inertia simulation which refers to using the same-size inertia flywheelto tested machines is usually adopted in inertia test. However, this method has manydisadvantages, such as inconvenient to adjust inertia, existing minimum constant error,leading to a huge space occupation, unable to eliminate inertia error, etc. Consideringthat motor is an energy conversion element between electrical and mechanical energyand is easy to control the output electromagnetic torque and motion, motor can be usedto replace flywheel to execute inertia test. The method using motor is called electric in-ertia simulation.Firstly, working principle of electric inertia simulation is analyzed. The impact ontested machines of inertia is analyzed in different perspectives. Inertia simulation evalu-ation system is established and simulation in software verifies the correctness of thetheory in order to build the foundation of electric inertia simulation theoretically.Secondly, the feasibility of the conventional single-stator load simulator applyingelectric inertia simulation is analyzed and the disadvantages of the load simulator areconcluded. Two novel load simulator using dual motors and dual-stator motor are pro-posed and their working principles and feasibilities are analyzed. Key issues aimingdifferent-structure load simulators applying electric inertia simulation are proposed.Thirdly, controlling method is designed for dual-stator load simulator. Decouplingcontrol of dual-stator is achieved by using real-time calculation of shaft model. A re-search on how to obtain the inertia-compensating torque signals (angular accelerationsignal) is conducted. The differentiating effects of using low-pass filter, nonlineartracking differentiator and Newton predicting method are compared for researching onnoise amplification and signal-delay.Finally, the simulation of the system is conducted in MATLAB/Simulink and thesimulation results verify the correctness and feasibility of the theories in this disserta- tion.