This paper takes N4700 dielectric high-voltage ceramic capacitors and GAC high-voltage ceramic capacitors as the research objects, systematically compares the differences in their technical parameters
Case Details
Technical Performance Comparison and Application scenario Analysis of High-voltage Ceramic Capacitors
This paper takes N4700 dielectric high-voltage ceramic capacitors and GAC high-voltage ceramic capacitors as the research objects, systematically compares the differences in their technical parameters, analyzes their performance in AC applications, and combines the technical requirements of power equipment to clarify the adaptation advantages of GAC capacitors and the typical application scenarios of N4700 dielectric.
一、Comparison and Classification Positioning of Core Technical Parameters
Both types of capacitors belong to Class II ceramic capacitors (high dielectric constant type), but there are significant differences in dielectric formulas and preparation processes. The specific technical parameters are compared as follows:
| Comparison Item |
Project N4700 High Voltage Ceramic Capacitor |
GAC High Voltage Ceramic Capacitor |
Notes |
| Product Specification |
40kV/1000pF |
40kV/1000pF |
Same rated voltage & capacitance baseline |
| Dielectric System |
Traditional Barium Titanate-based Ceramic |
Novel Doped Dielectric Ceramic |
Determines intrinsic dielectric properties & temperature stability |
| Manufacturing Process |
Dry Pressing - High Temp Sintering |
Tape Casting - Gradient Sintering |
Affects density, defect control & structural uniformity |
| Temp Coefficient (@85°C) |
ΔC/C = +28% |
ΔC/C = ±0.9% |
Critical for capacitance stability in high-temp environments |
| Rated Voltage |
DC 40kV / AC 10kV |
DC 40kV / AC 10kV |
Consistent AC/DC voltage withstand capability |
| Test Voltage |
DC 80kV / AC 45kV (2min) |
DC 80kV / AC 40kV (2min) |
Reflects insulation design safety margin (Note: AC value corrected) |
| Partial Discharge |
≤20pC |
≤3pC |
Core indicator of insulation aging sensitivity |
| Dimensions |
Φ45mm × H38mm (Thickness 34mm) |
Φ60mm × H22mm (Thickness 18mm) |
Key parameter for modular installation compatibility |
| Voltage Linearity |
ΔC/C > 5% (10-40kV AC) |
ΔC/C < 0.2% (10-40kV AC) |
Stability of capacitance vs. applied high voltage |
| Operating Temp Range |
-40℃ ~ +85℃ |
-55℃ ~ +125℃ |
Technical boundaries for environmental temperature adaptation |
| Material Code |
MZD45DL40KV102J |
MZD60GAC40KV102J |
Product traceability & supply chain management ID |
| Unit Price |
~¥200/pc |
~¥380/pc |
Foundational data for cost-effectiveness analysis |
二、Key performance differences in communication application scenarios
（一）The generation gap between medium materials and process technologies
- Temperature stability difference。The N4700 dielectric adopts the traditional dry pressing molding process, with many defects at the grain boundaries, resulting in a capacitance change rate as high as 28% at 85℃, which seriously affects the filtering accuracy and coupling stability in high-temperature environments. GAC capacitors achieve uniform dielectric doping at the nanoscale through the cast film injection process, enhancing the densification degree of the crystal structure. At 85℃, the capacitance change rate is controlled within 0.9%, completely solving the problem of high-temperature capacitance drift and meeting the long-term reliable operation requirements of outdoor power equipment under extreme working conditions of 80℃.
- Partial discharge control capability。In an AC electric field above 10kV, the grain boundary defects of N4700 dielectric are prone to cause partial discharge, with the discharge quantity ≤20pC. Long-term operation will accelerate insulation aging. Through dielectric modification and electrode structure optimization, GAC capacitors reduce the partial discharge to ≤3pC, meeting the strict insulation life requirements of the power industry (IEC 60628 standard), and significantly improving the operational reliability of the equipment.
- Wide temperature range adaptability。The upper limit of the operating temperature of the N4700 is 85℃. There is a risk of capacitance drift in high-temperature industrial environments or outdoor scenarios exposed to direct sunlight. GAC capacitors, relying on the Curie temperature control technology of new dielectric ceramics, achieve a wide operating temperature range of 55℃ to +125℃, meeting the dual demands of cold regions and high-temperature working conditions.
（二）Comparative analysis of electrical performance
- Voltage linearity：The voltage linearity of GAC ≤0.2% is far superior to that of N4700 > 5%. In scenarios with high requirements for capacitive reactance stability, such as reactive power compensation and harmonic filtering, it can avoid compensation accuracy deviations and system resonance risks caused by fluctuations in capacitance values.
- Test voltage difference：The AC test voltage of N4700 (45kV) is much higher than the rated working voltage (10kV), with a focus on short-term withstand voltage assessment. GAC adopts 4kV AC testing that is close to the actual working conditions, and pays more attention to the suppression of partial discharge during long-term operation, embodying the design concept of "reliability first".
三、The compatibility advantages of GAC high-voltage capacitors in power equipment
（一）Core advantage of environmental adaptability
- Stability under high-temperature working conditions。For the 80℃ high temperature on the surface of outdoor equipment in summer, the 0.9% capacitance stability of GAC ensures the constant parameters of the filter circuit and avoids the misoperation of the protection device caused by capacitance drift. The 28% change rate of the N4700 may lead to the failure of the filtering characteristics and threaten the system security.
- Insulation life optimization。The partial discharge capacity is reduced by more than 7 times (20pC→3pC), and combined with the wide temperature range working capability, the actual service life of GAC capacitors reaches 3 to 5 times that of N4700, significantly reducing the operation and maintenance costs and downtime risks of high-voltage equipment. It is particularly suitable for substations and transmission line equipment with high replacement difficulty.
- Structural design adaptability。The flat design of GAC (18mm thickness vs 34mm of N4700) increases the diameter to 60mm but reduces the height by 42%, which is more conducive to the planar layout and modular installation inside the high-voltage cabinet and conforms to the modern compact design trend of power equipment.
（二）Cost - effectiveness analysis of engineering applications
Although the cost of GAC is 90% higher than that of N4700, when considering the total life cycle cost, it shows significant advantages in the following scenarios:
- Scenarios with high reliability requirements：For instance, the capacitance stability and insulation life of coupling capacitors in 110kV and above substations and filter capacitors in new energy grid-connected inverters directly affect the system's energy efficiency and safety.
- Harsh environmental scenarios：In environments such as coastal salt spray, high-altitude temperature differences, and industrial high temperatures, the wide-temperature characteristics and low discharge capacity of GAC have become key selection criteria.
四、Typical application fields of N4700 medium
Although the N4700 high-voltage ceramic capacitor has limitations in power equipment, its specific technical characteristics are still applicable to the following scenarios:
（一）Low-voltage AC system
In power frequency AC circuits below 10kV, such as civil distribution equipment and reactive power compensation for low-voltage motors, the temperature change rate of N4700 (28%) and the partial discharge capacity (20pC) are within an acceptable range, and it has a significant cost advantage.
（二）Indoor stabilizing environment equipment
It is applied to temperature-controlled indoor switch cabinets and precision instrument coupling circuits. Its temperature range of 40℃ to +85℃ can meet the requirements of conventional environments and is suitable for mid-to-low-end equipment that is sensitive to cost.
（三）Dc bias scenario
In working conditions where DC voltage is dominant and AC components are relatively small (such as grounding capacitors in high-voltage DC transmission systems), the DC withstand voltage capability (40kV DC) of the N4700 and its relatively low cost make it competitive.
五、Conclusion
The performance difference between N4700 and GAC high-voltage ceramic capacitors essentially stems from the innovation of dielectric materials and process upgrades: GAC has achieved breakthroughs in core indicators such as temperature stability, partial discharge control, and wide-temperature adaptability through new dielectric ceramics and cast casting processes, making it the preferred solution for high-voltage AC equipment, especially in outdoor and high-reliability scenarios. The N4700 still holds a place in low-voltage, indoor and DC bias scenarios thanks to its cost advantage and basic withstand voltage capability. The design of power equipment should follow the principle of "balance between performance requirements and cost" : In AC systems above 10kV, harsh environments or scenarios with long life requirements, the technical advantages of GAC are irreplaceable. In low-voltage, indoor and cost-sensitive scenarios, the N4700 still has practical value. With the continuous advancement of the research and development of new dielectric materials, the performance boundaries of high-voltage capacitors will continue to expand, providing more precise solutions for fields such as smart grids and new energy.
