Design Of Direct Torque Control System For Counter-Rotating Permanent Magnet Synchronous Motors

Contra-rotating propeller(CRP)technology is an advanced underwater vehicle propulsion technology,which can keep the underwater vehicle moving straight forward,preventing side roll phenomenon and improving the operation efficiency of the system.In recent years,a kind of dual-rotor permanent magnet synchronous motor which can be used to drive the contra-rotating propeller is becoming a hot spot of research.The single stator and double rotor structure simplifies propulsion system,decreases the weight and volume of the mold,and reduces the fabricating cost.Therefore,this motor is widely used in the field of underwater electric propulsion.In this paper,a new type of disc single stator and rotor of counter rotating permanent magnet motor control system is investigated,and its engineering design is carried out.First,this paper introduces the application background and development of counter rotating permanent magnet synchronous motor.Then,the research status of counter rotating permanent magnet synchronous motor control strategy are expressed,as well as the defects of current control strategy.As a new disc counter rotating permanent magnet synchronous motor as the research object,its structure and working principle is introduced in detail.By analyzing the coordinate transform relationship,the counter rotating permanent magnet synchronous motor mathematical model of voltage,current and electromagnetic torque under d-q axis are established.In view of the existing shortcomings of counter-rotor permanent magnet synchronous motor control method,the two rotor was put under the same coordinate system to analyze its spatial flux vector relationship and a method for direct torque control based on the double rotor torque angle control is developed.This strategy can realize time-sharing control torque of bilateral rotor,by observing the bilateral rotor angle to real-time regulation of stator flux location.And the control system is built in matlab simulation model,The simulation results show that the proposed strategy can maintain bilateral rotor speed synchronous tracking for a given speed accurately.The main hardware of counter-rotor permanent magnet synchronous motor system is designed,DSP TMS320F28335 is used as the main control chip,and two rotating transformer are used to detect rotor position information.The intelligent power module IPM is used as the inverter of main circuit,and the driving circuit of controller,a power supply circuit,the DC link capacitor,detecting circuit are designed.Finally,based on TI company CCS3.1 DSP software development platform,the software part of the controller is designed,and a type of disc 2.2kW PMSM prototype is established.Through experimental analysis of adding and subtracting load,the correctness of the counter rotating permanent magnet synchronous motor control system is verified.