Motor energy storage circuit breaker

How solid state circuit breakers are transforming power systems?

With material science advancements, solid-state technology is now playing a crucial role in the modern power systems transformation. After revolutionizing the semiconductor industry, the technology is now penetrating the power systems protection, in the form of Solid State Circuit Breakers (SSCBs), which we cover in this article.

How does a medium voltage breaker work?

While the protective relay in medium voltage applications requires control power, the typical medium voltage breaker is closed and opened via mechanical springs in the breaker and there is a manual close and trip button on the face of the breaker along with a flag indicating breaker status. The operating mechanism is a stored-energy mechanism.

What is a solid state circuit breaker?

Solid state circuit breakers utilize power semiconductors to make and break the circuit. This is a fundamental shift in how circuits can be protected, since these semiconductors can be switched in the order of nanoseconds as opposed to milliseconds as in the case of traditional circuit breakers.

How does a circuit breaker work?

The control circuit’s logic is served by the anti-pump relay (Y), which prevents a continuous electrical close signal from causing the circuit breaker to repeatedly close after receiving a trip signal. Solenoids are used to power the breaker’s electrical operation.

What are circuit breakers used for?

The primary use of these breakers is circuit protection in the event of overload, short circuit and ground faults. The construction of these breakers consists of a frame, contacts, lever, trip unit and an actuator mechanism. The trip unit includes a thermal bimetallic strip that deflects in the event of an overload, thereby opening the contacts.

When a circuit breaker is energized?

The close coil (CC) is energized if the 52/b contact, LS contact, LCS contact, and Y contact are all closed. The 52/b contact automatically opens when the breaker closes, cutting off power to the close coil. Figure 3 shows the typical trip control circuit of a circuit breaker.