METHOD FOR AUTOMATIC LOAD TRANSFER (VERSIONS) AND DEVICE FOR ITS REALISATION Russian patent published in 2010 - IPC H02J9/06 

FIELD: electricity.

SUBSTANCE: method consists in measurement of positive-phase-sequence voltage of redundant power supply sources buses, linear voltages in buses of the main power supply source, angle between vectors of positive-phase-sequence voltages of the main and redundant power supply sources, separate measurement of the following for each of three phases at the input to the main source - value of existing current in phase and value of angle between vector of complex existing current in the same phase and vector sum of complex existing voltage between two other phases on buses of the main source and accepted as equal to 0-50% of share in identical complex existing voltage in buses of redundant source, measurement of angle between vectors of positive-phase-sequence voltages in the main and redundant sources in specified time gap and switching supply of main source buses to redundant one as any of measured voltages reduces in buses of main source below specified value or as angle increases between vectors of positive-phase-sequence voltages in buses of the main and redundant sources over specified value or as angle changes between vectors of positive-phase-sequence voltages in buses of the main and redundant sources in specified time gap over specified value, when simultaneously value of existing current in any phase at the input of the main supply source and value of angle between vector of complex existing current in the same phase and above specified vector sum reach specified area of values, and positive-phase-sequence voltage on buses of redundant supply source exceeds specified value.

EFFECT: improved efficiency.

4 cl, 2 dwg