Jolanta Sadura
supervisor: Jan Sroka
Abstract: The time-phased controller is the most important instrument of the control apparaturs in high voltage and high current laboratories. We set the time parameters of our test in it (time start, time stop, and electrical angle of signal). At normal work, the time-phased controller must wait for release by the operator to start the test. Sometimes the controller receives interference and starts the test without release. Such a situation is undesired and can be destructive for the device under test. Identification of the transient fields during the short circuit test is indispensable by assessing the hazard of EM interference in the control apparatus. The first step of our identification was to focus on powering the primary side of the test transformer by the unloaded secondary side. The measurement of fields suggested that repetitive damped oscillatory waves can cause malfunctioning of the controller. The origin of them is repetitive ignition and extinction of the arc by closing the circuit breaker in the medium voltage circuit.