METHOD FOR MONITORING THE STATE OF THE EARTHING CONTACTS OF A CONTACTOR CONTROLLABLE BY MEANS OF AN EXCITER COIL

• Main Author: COIS Olivier
• Format: Patent
• Language: English
• Published: 19.01.2017
• Subjects: BASIC ELECTRIC ELEMENTS; CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TOTRANSPORTATION; ELECTRIC EQUIPMENT OR PROPULSION OF ELECTRICALLY-PROPELLEDVEHICLES; ELECTRIC SWITCHES; ELECTRICITY; ELECTRODYNAMIC BRAKE SYSTEMS FOR VEHICLES, IN GENERAL; EMERGENCY PROTECTIVE DEVICES; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; MAGNETIC SUSPENSION OR LEVITATION FOR VEHICLES; MEASURING; MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES; MEASURING QUANTITY OF HEAT; MEASURING TEMPERATURE; PERFORMING OPERATIONS; PHYSICS; RELAYS; SELECTORS; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS; TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINSTCLIMATE CHANGE; TESTING; THERMALLY-SENSITIVE ELEMENTS NOT OTHERWISE PROVIDED FOR; TRANSPORTING; VEHICLES IN GENERAL

The present invention relates to a method for monitoring the state of the earthing contacts of a contactor controlled by an exciter coil, said contactor being operated as part of an isolation unit for galvanically isolating a voltage source from an electric consumer device connected to the voltage source, wherein a first power loss (22), which is transferred via the earthing contacts, and a second power loss (23), which is transferred via the exciter coil, are detected, and the first power loss (22) and the second power loss (23) are fed as input variables to a thermal model (21) of the contactor, the thermal model (21) determines an earthing contact temperature (24) according to at least one of the input variables and provides said contactor temperature as an output variable, and the provided earthing contact temperature (24) is evaluated.