Profile of GPO-3 (Introduction)

Application of GPO-3 in High-Voltage Switchgear

In high-voltage switchgear (such as KYN28 and other medium-to-high voltage metal-clad removable switchgear), GPO-3 laminates face significantly higher requirements than in low-voltage equipment. This is due to high operating voltages (typically 3.6 kV to 40.5 kV), intense electric fields, and severe potential arc damage.
In these high-voltage environments, GPO-3 plays a critical role in insulation barriers, arc resistance/extinction, and dynamic structural support.

1. Specific Applications in High-Voltage Switchgear

Phase Segregation Barriers and Rear Shrouds: Installed between the circuit breaker chamber, busbar chamber, and cable chamber. They serve as safety insulation barriers between high-voltage phases and to the ground, preventing phase-to-phase flashovers caused by overvoltage.
Mounting Plates for Contact Boxes and Wall Bushings: When high-voltage fixed contact boxes and wall bushings pass through metal enclosures, they must be mounted on GPO-3 insulation plates to isolate them from the metal frame, creating a reliable dielectric surface.
Busbar Supports and Insulating Clamps: High-voltage busbars generate massive electromagnetic loads during operation (especially during short-circuit events). GPO-3 is machined into busbar clamps and brackets to secure high-voltage copper bars and withstand intense dynamic mechanical stress.
Insulation Rods for Vacuum Circuit Breakers: In high-voltage circuit breaker handcarts, GPO-3 is used to manufacture insulating pull-rods, operating linkages, and protective insulation plates around the arc-chute to directly support high-voltage interruption processes.
Insulation for Earthing Switch Mechanism: Used for the operating linkages and transmission parts of high-voltage earthing switches to ensure absolute safety during grounding operations.

2. Key Performance Requirements for GPO-3 in High-Voltage Environments

To function reliably in high-voltage switchgear, GPO-3 must deliver several irreplaceable characteristics:
Excellent Comparative Tracking Index (CTI ≥ 600V): High-voltage enclosures are prone to condensation due to humidity and dust. GPO-3 has superior anti-creeping tracking capability, preventing conductive paths from forming even on contaminated surfaces.
Outstanding Arc Resistance (≥ 180 seconds): Intense, high-temperature arcs occur during high-voltage circuit breaker switching operations or fault flashovers. GPO-3 will not carbonize rapidly under localized high-temperature arc burning, effectively stopping the arc from spreading.
High Mechanical Strength and Impact Resistance: High-voltage circuit breakers operate with rapid switching actions, generating massive impact forces and short-circuit electromotive forces. GPO-3 features exceptionally high flexural and tensile strength, ensuring the structure does not deform or crack under high-frequency impacts.
Superior Dielectric Strength and Insulation Resistance: GPO-3 ensures full compliance with power-frequency withstand voltage and lightning impulse tests under high voltages (such as 10 kV or 35 kV).