Detection of partial discharge in dc motors by pulse method

In the production, transportation and processing of biological resources different electrical equipment is used, the integral part of which are DC machines. Energy efficiency and reliability of the production depends on the drives. The breakdown even of one engine may stop the production process and consequently entail losses. One reason for the failure of the DC motors is insulation damage due to exposure to partial discharge, however, a partial discharge detection technique has not been developed yet. For early warning of failure of DC machines and reducing the cost of unplanned stoppage on the replacement of a failed motor it is proposed to detect partial discharges at an early stage. There are many developments related to the detection of partial discharges. The majority of methods refer to equipment operating with AC voltage. For equipment operating at a constant voltage, reliable methods for partial discharge detection are not developed yet. Therefore, now the question of the diagnosis of partial discharge in the DC machine is quite relevant. Objective: to provide a method for detecting the partial discharge pulse applied using the DC voltage to the test object. Methods. A physical model for the detection of partial discharges was created. With the resulting model and electronic Tektronix oscilloscope type TDC-2012 the registration of partial discharge was carried out, for further processing and analysis on a computer. Results. The authors developed a method for the detection of partial discharge constant voltage by applying a short pulse. A series of tests, which revealed a number of certain laws by which we can judge the presence or absence of partial discharge in the test object, were performed by means of the created physical model. The authors obtained a patent on the basis of this research.