SYSTEM AND METHOD FOR DUAL MODE CONTROL OF A TURBOGENERATOR/MOTOR

摘要

A method of controlling a permanent magnet turbogenerator/motor includes providing a protected load connected in parallel with the turbogenerator/motor through a pulse width modulated inverter configured in a first operating mode to supply controlled current from the turbogenerator/motor to a utility electrical power source, and selectively connected to the utility electrical power source through an isolation device, monitoring the utility electrical power source, and automatically disconnecting the protected load from the utility electrical power source while reconfiguring the pulse width modulated inverter in a second operating mode to supply controlled voltage to the protected load when a fault is detected in the utility electrical power source. The present invention provides an external or integrated dual mode controller which can be used to provide automatic transitions of a turbogenerator/motor between grid-connected modes where a PWM inverter provides a controlled AC current source to stand-alone modes where the PWM inverter provides a controlled AC voltage source to a protected load. Three phase rotation sequence can be set to positive or negative rotation, or be set to the last measured rotation for the utility grid to enable automatic transitions from stand-alone to grid-connect modes. In addition, the present invention provides for detecting a reference phase angle of the three-phase power provided by a utility grid such that gradual synchronization/resynchronization of a protected parallel connected load can be performed by appropriately controlling the PWM inverter prior to re-connection to the utility grid.