| Water pumps and fans in the department of industry,agriculture,electric power,city life,and other fields have broad market space.At present,asynchronous motor and permanent magnet synchronous motor are widely used in the existing water pumps and fans system as the drive motor.However,the asynchronous motor has some problems such as low efficiency and serious heating during operation.The rotor of permanent magnet synchronous motor is generally designed with rare earth,which has the risk of demagnetization and relatively high cost at high temperature.The synchronous reluctance motor is divided into permanent magnet assisted synchronous reluctance motor(PMA-Syn RM)and no ferrite synchronous reluctance motor(NF-Syn RM),with no rare earth on the rotor,no risk of high temperature demagnetization,and relatively low cost,which is more suitable for application in water pump and fan occasions.However,the existing sensorless vector control method of permanent magnet synchronous motor generally adopts_di(28)0 method,which is not suitable for the application of no ferrite synchronous reluctance motor.The existing sensorless vector control method of synchronous reluctance motor has problems such as low efficiency,narrow speed range and so on.In this paper,a sensorless vector control scheme based on maximum torque per ampere,flux weakening control and model reference adaptive algorithm is studied.In order to compare the driving performance of PMA-Syn RM and NF-Syn RM,two kinds of motors were studied.Firstly,this paper describes the operation principle of NF-Syn RM and PMA-Syn RM,and introduces the mathematical models of the two motors in the ABC coordinate system,α-β coordinate system and d-q coordinate system.Secondly,In order to improve the current utilization rate,reduce the losses,and make the motor have a large output torque in the case of small current,this paper studies the maximum torque per ampere(MTPA)control.In order to expand the speed range of the motor,this paper studies the method of flux weakening control,and designs the negative i_d compensation magnetic weakening control method.In order to improve the response speed of speed and position estimation,and make sensorless control algorithm perform better in weak magnetic speed expansion region,a model reference adaptive algorithm based on current model is studied in this paper.Finally,in order to realize the control requirements of high efficiency,wide speed range and high estimation response speed,the above three algorithms were integrated,and a sensorless vector control scheme based on maximum torque per ampere control,flux weakening control and model reference adaptive algorithm was proposed.Then,a simulation model of the motor control system is established in the Simulink.The simulation consists of two parts.First,the sensorless vector control system based on MTPA is simulated and the starting ability and load resistance ability of NF-Syn RM and PMA-Syn RM are compared respectively under the control algorithm.Second,a sensorless vector control system model based on maximum torque current ratio control and flux weakening control is formed by integrating the magnetic weakness control algorithm into the above simulation model,and the simulation is carried out to compare the starting ability and anti-load ability of NF-Syn RM and PMA-Syn RM under the control system respectively.Finally,a test platform was built to verify the effectiveness and feasibility of the control system.And the integrated control algorithm is written into control code in Code Warrior.The experimental test is carried out from two aspects.First,the starting performance and steady-state performance of the motor under no-load and on-load conditions are tested.Second,the recovery ability test of the motor when the load changes suddenly.The experimental results show that the synchronous reluctance motor,driven by the above integrated control algorithm,has a better load capacity and anti-load disturbance ability,and has a better power factor and efficiency. |
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