GPO-3 Insulating Laminate in Electrical Insulation Applications

GPO-3 insulating laminate is a cornerstone material in electrical insulation, leveraging its exceptional electrical p...

GPO-3 insulating laminate is a cornerstone material in electrical insulation, leveraging its exceptional electrical properties, flame retardancy, mechanical strength, thermal resistance, and dimensional stability. It is indispensable in medium/high-voltage electrical equipment. Key application scenarios and technical advantages are detailed below:

I. Core Application Scenarios

1. Dry-Type Transformers (Especially Epoxy-Resin Cast – SCB Type)

• Insulating Frames/Spacers: Supports windings against electromagnetic forces and thermal stress; requires high mechanical strength and low shrinkage.

• End Insulation/Interlayer Insulation: Isolates HV/LV windings to prevent creepage/flashover; relies on high dielectric strength (>10 kV/mm).

• Blocks/Clamping Insulation: Secures windings and maintains cooling paths; demands thermal resistance (155°C class) and anti-creep properties.

• Lead Supports: Secures and insulates leads against vibration-induced short circuits.

2. Medium/Low-Voltage Switchgear (e.g., KYN28, MNS, GCK)

• Functional Barriers (Phase/Compartment Barriers):
  → Critical Role: Physically isolates phase busbars or functional units (e.g., circuit breaker/cable compartments) to block arc propagation.
  → Key Metric: CTI ≥ 600V (high comparative tracking index) ensures no conductive paths form in polluted/humid environments.

• Busbar Insulating Supports (Clamps/Brackets):
  → Secures Cu/Al busbars to maintain phase-to-phase/ground clearances (e.g., ≥125mm for 10kV systems).
  → Withstands short-circuit electrodynamic forces (flexural strength >200 MPa).

• Contactors/Arc Chute Insulation:
  → Encloses breaker contacts for insulation and arc control; requires arc resistance (>180s).

• Operating Plates/Shutters: Insulating substrates for mechanical interlock components.

3. Motors & Generators (HV/Special Motors)

• Slot Wedges/Slot Insulation: Secures windings and isolates cores; resists corona degradation (critical for VFD motors).

• End-Winding Phase Insulation: Prevents phase-to-phase shorts; requires flexibility for binding processes.

• Insulating End Shields/Ventilation Barriers: Isolates windings from housings; withstands thermal rise (155°C H-class continuous).

4. Busway Systems

• Phase-Separation Blocks: Isolates densely packed phase conductors; key metrics include dielectric strength and flame retardancy (UL94 V-0).

• Joint Insulating Covers: Protects busbar connections against foreign objects and electric shock.

5. Electrical Devices & Components

• Relay/Contactor Bases: Insulating support for live parts; dimensional stability ensures contact alignment.

• Terminal Blocks/Junction Plates: Isolates multiple conductors; high CTI prevents tracking.

• Insulating Operating Rods/Handles: Live-part isolation for manual switching devices.

II. Unmatched Technical Advantages

III. Selection & Design Guidelines

1. Thickness vs. Voltage Rating:
   → LV (400V): 1.5-3mm
   → MV (10kV): 4-8mm
   → HV (35kV+): Custom laminated structures required.

2. CTI Class Selection:
   → For Pollution Degree 3/4 (e.g., industrial sites), CTI≥600V is mandatory (e.g., GPO-3™).

3. Processing Compatibility:
   → CNC Machining: Complex parts (e.g., contactors)
   → Punching: Mass production of standard plates/spacers
   → Lamination: Ultra-thick components (>30mm) require multi-stage hot pressing.

4. Certification Requirements:
   → International: UL (E331910), IEC 60455
   → China: GB/T 5132.1 (Industrial rigid laminated sheets based on thermosetting resins for electrical purposes)

IV. Advantages Over Alternative Materials

V. Typical Failure Modes & Prevention

Failure Modes:

Surface tracking (low CTI), delamination at high temperatures (resin degradation), fracture under short-circuit forces (low strength).

Preventive Measures:

Use high-CTI grade (≥600V) materials in humid environments.

Design thermal expansion gaps.

Perform dynamic stability simulation (e.g., ANSYS) for busbar supports.

Conclusion

GPO-3’s core value in electrical insulation lies in its integrated trifecta of properties:
High-voltage reliability (dielectric strength + CTI)
Active safety protection (V-0 flame retardancy + arc resistance)
Structural functionality (mechanical strength + dimensional stability)
This establishes GPO-3 as the premier material for insulating structures in equipment up to 35kV, especially in dry-type transformers, MV switchgear, and motor insulation where it remains irreplaceable. Prioritize CTI class, thickness design, and operating temperature during selection.