Methods and systems for automatic testing of a relay

In a protective relay system comprising a signal interface for receiving power system inputs, a signal processor for processing the power system inputs in accordance with a predefined procedure and a data processor for analyzing the power system inputs as modified, a system for testing conditions of the protective relay system comprising:

• a test signal generator for generating a plurality of test signals and for outputting the same to the signal processor;
• a selector interfaced to the test signal generator and the signal interface and for selecting at least one of the plurality of test signal to provide an input to the signal processor on a continuous interval, and defining the same as a sampled selected test signal;
• the signal processor interfaced to accept the sampled selected test signal and for processing the same in accordance with a predefined procedure to generate an output of selected test data;
• and
• a test signal analyzer interfaced to accept the selected test data for comparing the selected test data with a set of reference data corresponding to the selected test signal resulting in a difference, if any, indicative of improper operation of the protective relay system.

A method for identifying a malfunctioning component in a protective relay system, wherein the protective relay system comprises a plurality of components serially interfaced in succession from a first component to a last component and wherein a plurality of sets of reference data are stored in a memory accessible by the protective relay system, each set of reference data corresponding to one of a plurality of test signals, the method comprising the steps of:

• selecting one of the plurality of components to test and defining the same as a selected component;
• generating one of the plurality of test signals and defining the same as a component test signal;
• providing the component test signal as an input to the selected component;
• processing the component test signal through the selected component and the components subsequent to the selected component in the succession of components in accordance with a predefined procedure to generate an output of selected component test data;
• and
• comparing the selected component test data with the set of reference data corresponding to the component test signal and if, based on the comparison, there is a difference, generating a difference output indicative of one of (1) improper operation of the selected component and (2) improper operation of one of the components subsequent to the selected component in the succession of components.

A system for automatic and continuous testing of a protective relay system comprising:

• a memory means for storing a plurality of sets of reference data each set corresponding to one of a plurality of test signals;
• a first processing means coupled to the memory means for generating the plurality of test signals based on corresponding sets of reference data on a continuous basis;
• a selection means coupled to the test signal generation means for selecting one of the plurality of test signals and defining the same as a selected test signal;
• a second processing means interfaced to accept the selected test signal and for processing the selected test signal in accordance with a predefined procedure to generate an output of selected test data;
• and
• said first processing means being interfaced to accept the selected test data and for comparing the selected test data with the set of reference data corresponding to the selected test signal to identify a difference, if any, indicative of improper operation of the protective relay system.