Winding Design And Performance Analysis Of Five-Phase Induction Motor

The five-phase induction motor is a multi-phase induction motor with a minimum number of phases and is widely used in fracturing pumps because of its good fault tolerance,high control freedom and suitability for high-power drive systems.In this dissertation,a five-phase induction motor with an output power of 15 k W is used as a research object.Subsequently,its three winding structures,star,pentagon and star-pentagon,are designed and optimized respectively.This includes the study and comparative analysis of the electromagnetic performance and fault-tolerant performance of these three winding types of motors under normal and fault operation conditions.Firstly,the winding design optimization of the five-phase induction motor is carried out.The traditional star winding structure is optimized,and a pentagon single winding structure and a new combined star-pentagon winding structure are designed.The magnetic field characteristics and starting characteristics of the motor under four different operating conditions(no-load,load,full-load and overload)are compared and analyzed by the finite element method,through comparative study,it can be seen that the performance of the star-pentagon winding is better under normal operation.Secondly,the spatial decoupling matrices of the three windings are derived from the spatial distribution of the different winding structures,and the mathematical models of the motors with the three winding structures are established.The expressions of the magnetic potential corresponding to single winding and combined winding are derived,the spatio-temporal harmonic magnetic potential is investigated,the harmonic content of the three windings are compared and analyzed,and the motor simulation model is built based on MATLAB/Simulink platform to verify the correctness of its mathematical model.Finally,the fault-tolerant performance of the five-phase induction motor under full-load and overload conditions with different fault states(one phase open and two phases open)is simulated by applying the field-circuit coupling method.The current variation of each phase,torque ripple,and efficiency are compared and analyzed,and the comparative study shows that the pentagon winding has better fault tolerance.The experimental study of the motor characteristics under no-load and 50N·m load is carried out,and the simulation results are verified.The results of both normal operation and fault operation of the motor are combined to show that the designed star-pentagon winding type has the best overall performance under different operating conditions.