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Large machinery and equipment commonly used high-voltage induction motor drives , variable speed coupled with the high-voltage inverter , the problems caused by bad waveform of the inverter output voltage to the motor , and feedback to the harmonic pollution because of its internal the high cost of power electronic devices , leading to its expensive ; series of power electronic devices in high-voltage inverter internal structure , so that it is difficult to guarantee the reliability ; aspects of the induction motor itself , its efficiency and power factor load rate is directly related to work performance decline in the low load rate is very obvious. In order to solve the above problems , taking into account the low voltage inverter use is widespread , the output waveform is good , cost-effective , high - power induction motor designed for low voltage AC motor winding structure of multiple parallel branches , each branch split into independent symmetrical three-phase system , powered by a low voltage inverter , respectively , when the system is in the low load rate state , can make part of the branch is to improve the performance of the system . This paper describes the structure and principle of this new type of motor , compared to the traditional induction motor , multidrop electromagnetic induction motor internal relations , calculated motor in different branches combinations excitation versus stator leakage reactance , as well as support the mutual inductance between the road ; multidrop induction motor mathematical model based on the switching process of the inverter drive system simulation; analysis of the impact on the motor in the case of each inverter not synchronized ; through the design and production of a 15kW 6 -pole , 6 branch induction motors , low-voltage -megawatt the multidrop induction motor design features are summarized , and the prototype parameters experiment with the performance of the experimental results confirm the theoretical analysis . The simulation and experimental results show that , when the motor is designed as a multi- branch induction motor , the road can be dispersed due to the low-voltage high-power current limit , lower control current of the drive system , low pressure by the higher cost of generic frequency conversion drive ; compared with the conventional induction motor , in the case of a low load rate , multi - branch of the induction motor performance is significantly better than the conventional induction motor .
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