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EP-4740233-A1 - METHOD FOR IMPROVED CONDITION MONITORING OF A POWER CIRCUIT BREAKER, POWER CIRCUIT BREAKER AND SWITCH PANEL HAVING SUCH A POWER CIRCUIT BREAKER

EP4740233A1EP 4740233 A1EP4740233 A1EP 4740233A1EP-4740233-A1

Abstract

The invention relates to a method for improved condition monitoring of a power circuit breaker (2), which is used in a switch panel (1.4) of a medium-voltage switchgear (100) as an overcurrent protection device, wherein a current value of a parameter, which is a measurement for the wear of switch contacts of the power circuit breaker (2), is transferred from a data store (3b) of the switch panel (1.4) to a data store (10c) of the power circuit breaker (2) when the power circuit breaker (2) is removed from the switch panel (1.4).

Inventors

  • IODICE, Luca

Assignees

  • Siemens Aktiengesellschaft

Dates

Publication Date
20260513
Application Date
20240801

Claims (6)

  1. 1. Method for improved condition monitoring of a circuit breaker (2) which is used in a switchgear panel (1.4) of a medium-voltage switchgear assembly (100) as an overcurrent protection device, wherein a current value of a parameter which is a measure of wear of switching contacts of the circuit breaker (2) is transmitted from a data memory (3b) of the switchgear panel (1.4) to a data memory (10c) of the circuit breaker (2) when the circuit breaker (2) is removed from the switchgear panel (1.4).
  2. 2. The method according to claim 1, wherein a current value of a parameter which is a measure of wear of switching contacts of the circuit breaker (2) is transferred from a data memory (10c) of the circuit breaker (2) to a data memory (3b) of the switchgear panel (1.4) when the circuit breaker (2) is inserted into the switchgear panel (1.4).
  3. 3. Method according to one of the preceding claims, wherein the parameter is a current-time integral.
  4. 4. Method according to one of the preceding claims, wherein the transmission of the value is based on RFID.
  5. 5. The method according to claim 4, wherein the data memory (10c) of the circuit breaker (2) is part of an RFID chip (10) arranged on the circuit breaker (2).
  6. 6. Circuit breaker (2) which can be used in a switchgear panel (1.4) of a medium-voltage switchgear assembly (100) as an overcurrent protection device, comprising a transceiver (10a) which is configured to receive a parameter from a communication device (14) of the switchgear panel (1.4) and to store it in a data memory (10c). 1. Switchgear panel (1.4) of a medium-voltage switchgear assembly (100), in which a circuit breaker (2) can be used as an overcurrent protection device, comprising a communication device (14) which is configured to send a parameter stored in a data memory (3b) of the switchgear panel (1.4) to a transceiver (10a) of the circuit breaker (2).

Description

Description Method for improved condition monitoring of a circuit breaker, circuit breaker and switchgear panel with such a circuit breaker The present invention relates to a method for improved condition monitoring, a circuit breaker and a switchgear panel of a medium-voltage switchgear. Medium-voltage switchgear is divided into switchgear panels, which are also simply referred to as "panels". As shown, for example, in EP 0 737 377 Al • (Siemens AG) 16.10.1996, a panel usually comprises a busbar compartment, a switch compartment, a cable connection compartment and a low-voltage compartment. The switch compartment contains an overcurrent protection device, e.g. a circuit breaker. The circuit breaker, e.g. a vacuum circuit breaker, can be movable on travel rails and can be withdrawn from the switch compartment for replacement, repair and maintenance, as in DE 101 04 890 Al (Siemens AG) 08.08.2002. The low-voltage compartment, which can be located above the switchgear compartment and is completely separated from the other rooms by walls, contains control, protection, and display devices for the circuit breaker. The switching contacts of the circuit breaker are designed for a maximum number of switching cycles - i.e. the number of possible opening operations. For example, in As described in DE 10 2004 020 045 Al (Siemens AG) 10.11.2005, circuit breaker manufacturers often state in technical specifications, data sheets and manuals for how many switching cycles a switching device is designed depending on the switched current (maximum number of switching cycles). Typical values are 10,000, 25,000 or 50,000 switching cycles. Based on the history (how many switching operations have already been carried out at which current), the number of remaining switching cycles can be estimated depending on the current. Another approach is to determine the energy that acts on a switching device during switching operations. When live switching contacts of the circuit breaker open, an arc can occur which leads to the switching contacts burning away. It is known (see, for example, DE 103 12 504 Al (Siemens AG) September 30, 2004) to determine the current status of contact wear resulting from such arcs on the basis of a current-time integral. The current-time integral is usually calculated as the value i 2 t, where i is the plasma current flowing over the arc and t is the arc duration. The value of the current-time integral is summed up for the switching operations that have already taken place. Depending on the type of breaker, there is a certain limit for the maximum total energy. For a circuit breaker in a medium-voltage switchgear, the current value of the circuit breaker's operating cycles is recorded by a mechanical operating cycle counter mounted on the circuit breaker. In contrast, the current value of the circuit breaker's current-time integral is stored in a data memory, also referred to simply as a "memory," in the low-voltage compartment of the bay. When a circuit breaker is removed from the bay for maintenance or repair, the current value of the removed circuit breaker's current-time integral remains stored in the low-voltage compartment but is not transferred to the removed circuit breaker. Thus, an operator who wishes to reuse the removed circuit breaker after maintenance or repair is missing important information about the circuit breaker's contact state. There is therefore a need for a method by which information about the contact state of a circuit breaker can be preserved. This object is achieved according to the invention by a method having the features specified in claim 1. This object is also achieved according to the invention by a circuit breaker having the features specified in claim 6. This object is also achieved according to the invention by a switchgear panel having the features specified in claim 7. The method is used for improved condition monitoring of a circuit breaker that is used as an overcurrent protection device in a switchgear panel of a medium-voltage switchgear. The term "circuit breaker" is not to be interpreted narrowly; rather, it includes all electrical switching devices that can be used in a medium-voltage switchgear to interrupt a current path, i.e. both protective devices and switching devices. The circuit breaker can be based on different technologies; e.g. a vacuum circuit breaker is just as possible as an air- or gas-based circuit breaker. The circuit breaker has at least two switching contacts that are brought out of contact to interrupt the current path and brought into contact with each other to (re-)establish the current path. According to the method, a current value of a parameter, which is a measure of wear of switching contacts of the circuit breaker, is transferred from a data memory of the switchgear panel to a data memory of the circuit breaker when the circuit breaker is removed from the switchgear panel. A circuit breaker according to the invention can be used in a sw