METHOD OF ULTRA-RAPID EMERGENCY PROTECTION OF AC POWER SYSTEM ELEMENTS AND DEVICE FOR ITS REALISATION Russian patent published in 2010 - IPC H02H7/26 H02H3/08 

FIELD: electricity.

SUBSTANCE: within each period of supply voltage the moment is registered, when specified voltage crosses zero value, from the moment specified current voltage phase is counted, forecasted values of current phase are identified for periodic component of the first current derivative of protected object, value of the first current derivative and current phase of its periodic component identify predicted value of amplitude of periodic current component of protected object, which is then compared to setpoint. Besides identification of predicted value of initial phase of periodic component in the first current derivative of protected object is started from the moment difference of predicted and measured actual values of grid voltage reaches specified value. To realise the method, emergency protection device is used for elements of AC power systems.

EFFECT: increased efficiency with preservation of emergency devices sensitivity and reliable recognition of emergency modes at early stage of their origination.

2 cl, 1 dwg