Abstract

This document provides a detailed technical analysis of HVC's high-voltage screw terminal ceramic capacitor architecture, with in-depth performance benchmarking against the AVX HP/HW/HK/HD/HE/HZ series. Targeting demanding applications such as power equipment, medical imaging, industrial NDT, and laser power supplies, HVC delivers a comprehensive performance upgrade and physically compatible drop-in replacement through N4700 Class 1 ceramic material, copper electrode technology, and innovative dual-chip structure — offering engineers a high-reliability, short-lead-time alternative.

1. Technical Background & Design Challenges

High-voltage screw terminal ceramic capacitors (doorknob capacitors) face three major design challenges:

• Dielectric Selection: AVX used strontium titanate Class 2 ceramics, which achieve energy densities of 50-100 J/liter but fall short of Class 1 ceramics in temperature stability and long-term reliability.
• Partial Discharge Control: In demanding AC applications such as SF6 breakers, partial discharge must be ≤5pC, placing extreme demands on electrode technology and package design.
• Ultra-High Voltage: AVX was the only brand offering 100KV-rated doorknob capacitors. With their market exit, this specification has essentially become unavailable.

2. HVC Core Technology: Breakthrough from Materials to Structure

2.1 N4700 Class 1 Ceramic Material

HVC uses N4700 Class 1 ceramic across its entire product line, offering the following advantages over AVX's strontium-based Class 2 ceramics:

• Lower Dissipation Factor: N4700 D.F. ≤ 0.001 @ 1KHz, an order of magnitude lower than AVX's Class 2 ceramics.
• Wider Operating Temperature: -55℃ to +125℃, superior to AVX's -35℃ to +85℃.
• Higher Insulation Resistance: N4700 volume resistivity is far higher than Class 2 ceramics, minimizing leakage current under HV.

2.2 Copper Electrode Plating Technology

HVC uses copper electrodes in place of traditional silver. Copper ions migrate at only 1/100 the rate of silver ions, dramatically improving reliability under sustained HV stress. HVC's copper electrodes pass the same stringent partial discharge tests (≤5pC) required by AVX customers.

2.3 Innovative Dual-Chip Structure

HVC breaks through single-chip package limits: series configuration achieves 100KV/120KV/150KV ultra-high voltage, parallel configuration delivers expanded capacitance coverage. For example, HVCT8G-50KV-DL80-502M (50KV 5000pF) uses dual-chip parallel design, far exceeding AVX's original 1650pF maximum.

3. Key Specification Benchmark

4. Complete HP Series Replacement Table (64 Models)

15-30KV HP Series Complete Replacement Table

40-100KV HP Series Complete Replacement Table

5. HVC Part Number Decoder

HVCT8G-[Voltage]-[Size Code]-[Capacitance Code]

6. Typical Replacement Cases

7. Microstructure & Material Engineering

• N4700 Grain Control: Precise sintering control keeps grain size at 1-3µm, achieving over 98% theoretical density.
• Copper Electrode Interface Optimization: Multi-layer co-firing creates a metallurgical bond between copper electrode and ceramic substrate, with interface strength 40% higher than silver electrodes.
• PD Control: Optimized end electrode design ensures partial discharge ≤5pC at rated AC voltage, meeting power equipment requirements.

8. Market Track Record: Full Coverage from AVX to Vishay/Murata

Since 2018, HVC has executed multiple replacement projects:

• GE Healthcare — Successfully replaced Murata DHS and Vishay 715C series for CT/X-ray medical equipment
• ABB — Replaced Vishay 715C series for SF6 breakers and power equipment
• Nikon / Konica Minolta — Replaced original Murata models
• Baker Hughes — Replaced Vishay models for oil exploration equipment