The identification of the different causes of a Medium Voltage (MV) switchgear failure is a complex task. Among the conditions contributing to failure, thermal cycling due to loose joints and electrical components may act as a trigger for fault. This paper presents an experimental analysis of temperature variation taking place in 27 different points of a MV switchgear and originating from loose mechanical and electrical joints in the busbars, compared to the normal operating condition. The loose joints - due to improper installation, vibrations, or ageing of components - are obtained by applying a controlled clamping below the recommended operational value of 45 Nm torque, to six busbar joint screws (two for each phase). Results show that when the applied clamping goes below 10% of the recommended value, temperature does not rise significantly in points other than the loose ones, while the main circuits exhibit a detectable variation of their electrical resistance.
Temperature Rise in MV Switchgears: the Role of Loose Busbar Joints / Spinsante, S.; Iadarola, G.; Mazzocchi, G.; Romagnoli, C.. - ELETTRONICO. - (2022), pp. 51-56. (Intervento presentato al convegno 25th IMEKO TC-4 International Symposium on Measurement of Electrical Quantities, IMEKO TC-4 2022 and 23rd International Workshop on ADC and DAC Modelling and Testing, IWADC 2022 tenutosi a Brescia, Italy nel 2022).
Temperature Rise in MV Switchgears: the Role of Loose Busbar Joints
Spinsante S.
Primo
Investigation
;Iadarola G.
Secondo
Writing – Review & Editing
;
2022-01-01
Abstract
The identification of the different causes of a Medium Voltage (MV) switchgear failure is a complex task. Among the conditions contributing to failure, thermal cycling due to loose joints and electrical components may act as a trigger for fault. This paper presents an experimental analysis of temperature variation taking place in 27 different points of a MV switchgear and originating from loose mechanical and electrical joints in the busbars, compared to the normal operating condition. The loose joints - due to improper installation, vibrations, or ageing of components - are obtained by applying a controlled clamping below the recommended operational value of 45 Nm torque, to six busbar joint screws (two for each phase). Results show that when the applied clamping goes below 10% of the recommended value, temperature does not rise significantly in points other than the loose ones, while the main circuits exhibit a detectable variation of their electrical resistance.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
