Precise signal, clear communication: High-voltage door handle capacitors enable power line carrier communication coupling devices
Drawing:
Parameters:
| No. | Specification | Dissipation | Withstanding voltage | Insulation resistance | Dimension(mm) | ||||
| 1 | 20kV-2000pF |   ≦0.0040  |    1.5Ur● 1min  |    ≧1.0×105MΩ  |  D | H | L | D | M | 
| 2 | 20kV-10000pF | 45 | 19 | 23 | 12 | 5 | |||
| 3 | 20kV-18000pF | 65 | 15 | 19 | 12 | 5 | |||
| 4 | 30kV-1000pF | 80 | 17 | 25 | 12 | 5 | |||
| 5 | 30kV-2700pF | 45 | 24 | 32 | 12 | 4 | |||
| 6 | 30kV-12000pF | 60 | 20 | 28 | 12 | 4 | |||
| 7 | 40kV-150pF | 20 | 33 | 41 | 8 | 4 | |||
| 8 | 40kV-500pF | 28 | 33 | 41 | 8 | 4 | |||
| 9 | 40kV-7500pF | 80 | 24 | 29 | 12 | 6 | |||
| 10 | 40kV-10000pF | 80 | 22 | 26 | 16 | 5 | |||
| 11 | 50kV-1000pF | 50 | 30 | 34 | 12 | 4 | |||
| 12 | 50kV-1000pF | 32 | 27 | 31 | 16 | 5 | |||
| 13 | 50kV-5600pF | 80 | 31 | 35 | 16 | 5 | |||
| 14 | 60kV-1500pF | 50 | 31 | 34 | 12 | 5 | |||
| 15 | 60kV-3000pF | 65 | 32 | 35 | 16 | 5 | |||
| 16 | 100kV-500pF | 50 | 54 | 58 | 12 | 5 | |||
| 17 | 100kV-2000pF | 51 | 32 | 35 | 16 | 5 | |||
| 18 | Insulator type 100kV-1500pF | 68 | 36 | 40 | 16 | 5 | |||
| 19 | 150kV-820pF | 65 | 95 | 100 | 12 | 5 | |||
| 20 | 200kV-600pF | 50 | 90 | 94 | 16 | 5 | |||
In power line carrier communication systems, efficient and low-distortion coupling of high-frequency communication signals onto high-voltage power lines without interfering with industrial frequency power transmission is crucial to communication quality. The combined filter and coupling capacitors in the power line carrier coupling device together form the "signal gateway" for this process. The high-voltage doorknob capacitor is the core component responsible for energy exchange and frequency selection within this gateway.
Challenges: Impedance Matching and Nonlinear Distortion
In a coupling device, filters must perform two major functions:
Impedance Conversion: Matching the high impedance of the power line (approximately 300-400Ω) with the low impedance of the communication cable.
Capacitive Reactance Compensation and Filtering: Compensating for the capacitive reactance of the coupling capacitor and working with it to form a bandpass or high-pass filter circuit, allowing only signals in a specific frequency band to pass and suppressing out-of-band noise.
Poor capacitor performance, such as unstable capacitance or excessive internal losses, can lead to:
Impedance mismatch, causing signal reflections and increased transmission attenuation.
Nonlinear distortion, generating harmonics, disrupting signal integrity, and reducing the communication signal-to-noise ratio.