✅ Dynamic Structure of a Medium Voltage Vacuum Circuit Breaker
The dynamic structure refers to how each part of the VCB moves and interacts from the moment a command is received until the operation is completed - similar to analyzing the muscle movements of an athlete during a sprint.
A typical permanent magnetic actuator (PMA) VCB consists of two main dynamic systems:
🧲 1. Power Drive & Control System (Command & Energy)
This is the "brain and heart" of the breaker. It receives the command and provides the energy.
| Component | Function |
|---|---|
| Permanent Magnetic Actuator (PMA) | Uses permanent magnets to hold the closed/open position without mechanical latches. Simple, reliable, and fast. |
| Intelligent Control Unit | Analyzes commands and controls the timing of discharging the storage capacitor to the closing or tripping coil. Enables smart operations. |
| Energy Storage Capacitor | Stores electrical energy and releases it in milliseconds to generate the powerful electromagnetic force needed for operation. |
⚙️ 2. Mechanical Transmission & Execution System (Action & Arc Quenching)
This is the "muscles and skeleton" that execute the mechanical motion and extinguish the arc.
| Component | Function |
|---|---|
| Transmission Mechanism | Links, cranks, and levers that transfer and amplify motion from the actuator to the vacuum interrupter. |
| Vacuum Interrupter | The core of the breaker. High vacuum inside is the medium for arc quenching and current interruption. |
| Contact System | Moving contact + fixed contact. Closes to carry current; opens to create and then extinguish the arc. |
| Contact Spring | Provides the final contact pressure when closed, ensuring reliable conductivity. Also stores energy for the opening stroke. |
⚡ Dynamic Process Example: Closing Operation
Command & Charging
The control unit receives a closing command. The storage capacitor is already charged.
Coil Energized & Magnetic Field Built
The control unit discharges current into the closing coil, generating a strong electromagnetic field.
Overcome Holding Force
The magnetic force overcomes the permanent magnet's holding force in the open position, and the moving core starts to travel.
Transmission & Contact Closing
The motion is amplified through the transmission mechanism, pushing the moving contact toward the fixed contact at high speed.
Contact Bounce & Latching
After impact, the contacts may bounce slightly. The contact spring provides final contact pressure. The moving core reaches the closed position, and the permanent magnets hold it there - no power needed.
Coil De-energized
The control unit cuts off coil current upon sensing the closed position. The operation is complete.
Products Description
VTZ-15/T5000-63 indoor high-voltage generator circuit breaker is a vacuum circuit breaker designed for generator outlets in 15 kV and lower, three-phase AC 50 Hz systems.
It is primarily utilized in the plant auxiliary circuits of small to medium-sized hydroelectric generator units, thermal power generators, new energy generation systems, and industrial facilities-such as those in the chemical and processing sectors-that operate with their own captive power generation capabilities.
Our address
No. 1 East Gaoxin Avenue in the High-Tech Development Zone of Baoji City, Shaanxi Province, China
Phone Number
+86 180 9176 5658
xdtz03@westpowerelectric.com
