97 / 2024-04-11 23:23:23

MEDIUM VOLTAGE VACUUM CIRCUIT BREAKERS SWITCHING PERFORMANCE IMPACTING PARAMETERS SYNOPSIS

vacuum circuit breakers,Switching,Performance,mechanical analysis,optimal design,Finite Element Analysis (FEA)

Medium Voltage vacuum Circuit Breakers

Switching performance impacting parameters Synopsis



Saïd Attak*, Thomas Song*, Achang Wu*, Jeffer Han**, Jean-Pierre Meley***,

*Schneider Electric, Xiamen AVX, China

**Schneider Electric, Shanghai, China

***Schneider Electric, Grenoble 38 TEC, France

Email: said.attak@se.com





For proper current switching operations of Vacuum Circuit Breakers, many identified parameters being critical for short time current withstanding capacity of the system components, for short circuit current making and breaking and for capacitive current breaking operations were identified and analyzed. To assess the robustness and reliability of every circuit breaker newly developed, the behavior of these factors is now systematically taken under consideration and controlled to ensure a very high-quality level.



The main identified impacting parameters and influencing one another which were analyzed are the following:

 

• Proper guiding systems at vacuum interrupter level.


• Appropriate guiding at kinematic level.


• Optimized Energy level allowing proper mechanical characteristics and operability at low temperature.


• Perfect the equilibrium between moving and fixed masses.


• Harmonize the balance between Stiffness and Damping properties of the main frame.


• Suitable arrangement and guiding of considered copper flexible contact (shunts).


• Electrodynamic and repulsion respective resulting forces consideration


• Contact pressure spring force and Snatch Gap allowing hammer effect (overtravel).


• Contact bouncing time of each phase.


• Closing and Opening velocities and strokes of each phase.


• Un-welding forces generated within each pole.


• Phase to phase opening and closing synchronization.

The main criteria investigated here are the design of circuit breaker poles, their kinematic transmission efficiency and the frame stiffness and damping properties, all changes made allowing to:

 

• Refine the efficiency of circuit breakers and optimize both short time current proper withstanding as well as stringent switching performances capability.

 

• Appreciate complex phenomenon occurring during closing and opening operation phases of medium voltage circuit breakers.

 

• Expose the subtitle equilibrium of most revealed impacting parameters being key to enhance switching performances of considered circuit breaker.

Those explorations were performed following 3 core areas:

 

• Mechanical design analysis


• Mechanical & Electromagnetic Finite Element Analysis


• Design of experiment allowing to uncover most impacting parameters.

Main observations will be reported in this paper, we will present factors most impacting switching performances that were revealed during the design of experiment stage. Based on those findings, new Vacuum Circuit Breakers were developed and industrialized supporting the validity and benefit of such development approach.

The interaction between parameters and the promising AI is offering us to potentially better master their correlation and dynamics for the future.