Miniaturized High-Density Hall-Effect Low Voltage Current Transformer (LVCT) Solution Solusyon ng Miniaturized High-Density Hall-Effect Low Voltage Current Transformer (LVCT)
I. Technical Challenges & Objectives
Ang mga tradisyonal na current transformers (CTs) ay may malaking sukat, limitasyon sa AC-only measurement, at panganib ng magnetic saturation. Upang tugunan ang pangangailangan ng modernong kompak na electronic systems (halimbawa, battery management, servo drives, kompak na inverters) para sa pag-save ng espasyo, lightweight design, DC detection, at high-frequency response, ina-alok ng solusyong ito ang miniaturized, high-density, AC/DC-compatible Hall-effect current sensing approach.
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 na naka-embed sa specially designed annular flux-concentrating core (high-permeability material).
- Magnetic Field Cancellation Principle:
- Ang magnetic field na gawa ng primary current ay nadetect ng Hall chip.
- Ang high-gain feedback circuit ay nag-drive ng secondary coil upang lumikha ng counteracting field, na nagpapahintulot ng real-time "zero-flux" state.
- Ang feedback current ay eksaktong mirroring ang primary current, na nagbabawas ng nonlinearity at temperature drift na inherent sa open-loop designs.
- Highly Integrated Signal Processing
- Dedicated ASIC Integration:
- Low-noise amplification ng Hall signals
- Dynamic offset cancellation circuitry
- High-precision temperature compensation algorithm (nagbibigay ng mitigation sa silicon thermal drift)
- Adjustable low-pass filtering (typical: 100–250 kHz)
- Integrated voltage reference at output driver
- Ultra-Compact Structural Design
- Miniaturized Core: Optimized magnetic circuit na may apertures na buntot na Ø5mm (standard through-hole) o rectangular surface-mount openings.
- SMD/Through-Hole Packaging:
- Surface-mount packages (halimbawa, SMD-8) para sa direct PCB assembly, taas ≤ 10mm.
- Through-hole design (leadless structure) na nagpapahintulot ng direct conductor routing sa pamamagitan ng core aperture, na nagpapahintulot ng galvanically isolated installation.
III. Key Advantages & Value Proposition
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Dimension |
Advantage |
Value Proposition |
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Physical |
- >70% size reduction |
High-density PCB compatibility |
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- Ultralight weight (<5g) |
Ideal para sa drones/handheld devices |
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- SMD/through-hole structures |
Simplified installation |
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Electrical |
- AC/DC current measurement (DC–100kHz) |
EV powertrain monitoring |
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- Galvanic isolation (>2.5kV) |
Solar inverter OCP/PV leakage detection |
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- Virtually immune to saturation |
High-accuracy battery SOC estimation |
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- Low thermal drift (<0.05%/°C) |
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System Cost |
- Microamp-level quiescent current |
Extended battery life in portable devices |
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- Zero external compensation components |
Reduced BOM & calibration costs |
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- Full SMT automation compatibility |
Scalable for million-unit production |
IV. Target Applications
- Battery Management (BMS): High-precision DC current detection (±1%) para sa EV/ESS charge-discharge cycles.
- Compact Inverters: Phase current control sa 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.
