Miniaturized High-Density Hall-Effect Low Voltage Current Transformer (LVCT) Solution Solusyon sa Miniaturized High-Density Hall-Effect Low Voltage Current Transformer (LVCT)
I. Teknikal nga mga Hamon & Mga Layunin
Ang tradisyonal nga mga current transformers (CTs) adunay dako nga sukat, limitasyon sa pag-sukod sa AC lamang, ug panganib sa magnetic saturation. Ang solusyon kini naghatag og miniaturized, high-density, AC/DC-compatible Hall-effect current sensing approach aron mapugos ang panginahanglan sa modernong compact electronic systems (e.g., battery management, servo drives, compact inverters) para sa pag-save sa espasyo, lightweight design, DC detection, ug high-frequency response.
II. Core Technology: Closed-Loop Flux-Balance Hall Sensor + ASIC Integration
- Miniature Magnetic Circuit & Sensing Core
- Closed-Loop Flux-Balance Architecture: Micro silicon-based Hall chip embedded within a specially designed annular flux-concentrating core (high-permeability material).
- Magnetic Field Cancellation Principle:
- Ang primary current-generated magnetic field detected by the Hall chip.
- High-gain feedback circuit drives secondary coil to generate counteracting field, achieving real-time "zero-flux" state.
- Feedback current precisely mirrors primary current, eliminating nonlinearity and temperature drift inherent to open-loop designs.
- Highly Integrated Signal Processing
- Dedicated ASIC Integration:
- Low-noise amplification of Hall signals
- Dynamic offset cancellation circuitry
- High-precision temperature compensation algorithm (mitigating silicon thermal drift)
- Adjustable low-pass filtering (typical: 100–250 kHz)
- Integrated voltage reference and output driver
- Ultra-Compact Structural Design
- Miniaturized Core: Optimized magnetic circuit with apertures as small as Ø5mm (standard through-hole) or rectangular surface-mount openings.
- SMD/Through-Hole Packaging:
- Surface-mount packages (e.g., SMD-8) for direct PCB assembly, height ≤ 10mm.
- Through-hole design (leadless structure) allows direct conductor routing through core aperture, enabling galvanically isolated installation.
III. Key Advantages & Value Proposition
|
Dimension |
Advantage |
Value Proposition |
|
Physical |
- >70% size reduction |
High-density PCB compatibility |
|
- Ultralight weight (<5g) |
Ideal for drones/handheld devices |
|
|
- SMD/through-hole structures |
Simplified installation |
|
|
Electrical |
- AC/DC current measurement (DC–100kHz) |
EV powertrain monitoring |
|
- Galvanic isolation (>2.5kV) |
Solar inverter OCP/PV leakage detection |
|
|
- Virtually immune to saturation |
High-accuracy battery SOC estimation |
|
|
- Low thermal drift (<0.05%/°C) |
||
|
System Cost |
- Microamp-level quiescent current |
Extended battery life in portable devices |
|
- Zero external compensation components |
Reduced BOM & calibration costs |
|
|
- Full SMT automation compatibility |
Scalable for million-unit production |
IV. Target Applications
- Battery Management (BMS): High-precision DC current detection (±1%) for EV/ESS charge-discharge cycles.
- Compact Inverters: Phase current control in IGBT modules (100A-range SMD solutions).
- Servo Drives: Multi-axis motor current sampling (parallel SMD CT arrays).
- Smart Meters: DC-component metering (tamper/theft prevention).
- Data Center PSUs: Rack-level current monitoring (high-density through-hole integration).
V. Scalability & Future Roadmap
- Multi-Range Coverage: Single package supports 20A–500A ranges (via core/coil ratio optimization).
- Digital Interface: Optional I²C/SPI output variants (ADC-integrated ASIC).
- High-Precision Tier: Closed-loop achieves 0.5% linearity (25°C), meeting Class 1 metering standards.
