Electronic Current Transformer (ECT) High-Precision Solution
I. Pain Points & Challenges
Traditional electromagnetic current transformers (CTs) suffer from inherent limitations like magnetic saturation, narrow bandwidth, and large size, making it difficult to meet the smart grid's demands for high-precision and wide-dynamic-range measurement. Especially under large current surges or complex harmonic operating conditions, accuracy readily degrades, compromising the safety and economic operation of power systems.
II. Core Technological Breakthrough: Multi-Dimensional Accuracy Enhancement Architecture
This solution achieves ±0.1% accuracy class (Class 0.1) across all operating conditions, exceeding IEC 61869 standard requirements, by integrating sensor technology innovations, intelligent compensation algorithms, and optimized digital signal processing.
Key Technological Approaches:
- Low-Noise Sensing Layer Innovation
- High-Linearity Air-Core Coil Design: Employs precision winding techniques and nanocrystalline magnetic cores to reduce high-frequency eddy current losses, ensuring phase error < 0.1° within the 10Hz ~ 5kHz frequency band.
- Micro-Current Self-Powering Technology: Innovative self-powered circuit design (minimum starting current 0.5A) eliminates external power supply interference, enhancing low-current measurement accuracy.
- Dynamic Temperature Compensation System
- Multi-Sensor Fusion Calibration: Integrates temperature/vibration/electric field sensors to build a real-time environmental parameter matrix, dynamically correcting drift errors via an AI compensation model (LSTM neural network).
- Anti-Interference Digital Processing Chain
|
Module |
Technical Solution |
Accuracy Contribution |
|
ADC Sampling |
24-bit Σ-Δ ADC + Synchronous Clock Distribution |
Reduces quantization noise by 60% |
|
Digital Filtering |
Adaptive FIR Filter Bank |
Harmonic Rejection Ratio > 80dB |
|
Data Transmission |
Triple-Redundant Fiber Channel + CRC32 Checksum |
Bit Error Rate < 10⁻¹² |
III. Accuracy Verification Comparison (Typical Conditions)
|
Test Condition |
Traditional CT Error |
Proposed ECT Solution Error |
Improvement Factor |
|
Rated Current (50Hz) |
±0.5% |
±0.05% |
10x |
|
20% Overload (30% Harmonics) |
±2.1% |
±0.12% |
17.5x |
|
Extreme Low Temp (-40°C) |
±1.8% |
±0.15% |
12x |
IV. Application Value
- Grid Security: Fault current measurement accuracy improved to 99.9%, ensuring relay protection correct operation rate > 99.99%.
- Energy Efficiency Management: Wide-band harmonic measurement error < 0.5%, enabling precise power quality analysis.
- Intelligent Expansion: Natively supports IEC 61850-9-2LE protocol, enabling seamless integration into digital substation systems.
