Multiphase motor channel fault ride-through operation control method

Abstract

The invention discloses a multiphase motor channel fault ride-through operation control method. With the multiphase motor channel fault ride-through operation control method adopted, when a certain orseveral channels fail, fault-tolerant on-line channel switching non-stop ride-through operation is realized; and during a process in which the channel fails or the failed channel is removed, the over-current protection of the inverter alternating-current side (motor winding side) of the remaining operating channels, the voltage stabilization control of the inverter direct-current bus-bar side ofthe remaining operating channels and inverter magnetic field compensation integrated coordination control are implemented. With the method adopted, fast, stable and safe fault-tolerant on-line channelswitching non-stop ride-through operation of a multiphase motor is realized. The method can be used for high-power electromechanical energy conversion occasions such as ship propulsion, track traction and wind power generation.

Description

technical field [0001] The invention belongs to the technical field of AC motor control, and in particular relates to a multi-phase motor multi-channel running channel failure online cut-off non-stop through operation control method, so as to realize the motor multi-channel fast, stable and safe online cut-off non-stop through operation, application It is used in high-power electromechanical energy conversion occasions such as ship propulsion, rail traction, mining machinery transmission, metallurgical steel rolling, speed regulation of fan pumps, and wind power generation. Background technique [0002] With the development of power electronic devices and technologies, power converters can break through the traditional three-phase mode and adopt multi-phase mode, so that the motor can get rid of the limitation of the phase number of the grid. [0003] Compared with three-phase motors, the significant advantages of multi-phase motors (number of phases m>3) are as follows: ...

AI Technical Summary

Problems solved by technology

[0008] In order to give full play to the advantages of high reliability of the multi-phase system, the system is required to be able to run through the online switching channel without stopping when one or several channels fail. However, the motor is an electromagnetically coupled whole. , due to the sudden change of the voltage and current of the stator winding of the motor, the transient flux linkage of the stator winding changes, and inrush current and bus overvoltage are generated in the remaining operating channels, causing a fault shutdown and making the online switching channel fail

For example, a single phase-to-ground or phase-to-phase short circuit of a stator winding in a certain channel causes a sudden change in the machine terminal voltage, which will generate a negative sequence and a transient DC static magnetic field in the motor, causing the rotor winding or other stator windings to induce a high back EMF, resulting in a transient high voltage. Large currents cause drastic changes in electromagnetic torque, pulsations and oscillations, DC bus voltage pumps up, cause overcurrent or overvoltage faults, and even damage system components

[0009] At present, there is still a lack of detailed research on the transition process control between normal, fault, and fault-tolerant conditions, which makes it difficult to apply fault-tolerant operation to actual engineering

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