Back to results
US 7,444,266 B2Granted
Control system for a transformer or reactor
AssigneeABB Technology AG
InventorsBengt-Olof Stenestam, Gunnar Andersson
Life of this patent
Estimating the term…
Abstract
A universal control and diagnostic system for a transformer that may be retrofit with existing control and tap-changer equipment, the system providing for remote monitoring and control of the equipment and for measuring various criteria associated with the tap-changer to substantially minimize damage to the equipment during a maneuver and for substantially avoiding carbonization of a connected contact.
Claims10
A diagnostic system for protecting a tap-changer comprising:
- a sensor, positioned to detect temperature changes;
- an initial measured temperature, indicating an initial temperature measured by said sensor prior to initiating a tap change;
- a calculated temperature value, calculated according to the particular tap change to take place;
- a threshold value determined based on said initial measured temperature and said calculated temperature value, at which an alarm is generated;
- a second measured temperature indicating an actual temperature measured by said sensor after a tap change has been initiated;
- said alarm generated by the diagnostic system if said second measured temperature exceeds said threshold value.
3 more elements
A diagnostic system for preventing degradation to electrical contacts in a tap-changer comprising:
- a contact measurement device for measuring a contact position;
- a contact signal generated by said contact measurement device, indicative of whether the contact is open or closed;
- a threshold time value related to a maximum amount of time that the contact may be in the contact position;
- a controller for receiving the contact signal and generating a closed time value based on the contact signal;
- said controller comparing the closed time value to said threshold time value to determine if the closed time value exceeds said threshold time value;
- a warning message generated by the diagnostic system indicating that said threshold time value has been exceeded.
3 more elements
Dependencies are inferred from the claim text.