According to relevant statistics, as of the end of October 2025, the total number of charging piles in my country reached 18.645 million, a year-on-year increase of 54.0%. Recently, four departments, including the National Development and Reform Commission, jointly issued a document to vigorously develop high-power charging facilities. With the gradual popularization of 800V high-voltage systems and 350kW supercharging technology, DC leakage current in charging piles has also attracted much attention from the industry. Traditional AC leakage current devices (RCDs) cannot detect smooth or pulsating DC leakage current, leading to malfunctions or missed detections. According to the requirements of IEC 62955 Mode 3, charging piles must have DC 6mA leakage current detection capability, but traditional Hall effect sensors are costly and lack accuracy, making them unsuitable for this requirement.
In this context, fluxgate magnetometer technology, with its advantages of high precision, low temperature drift, and wide bandwidth response, has become the preferred solution for DC leakage current detection. CHIPSENSE fluxgate current sensor is one of them.
The following discussion focuses solely on leakage current detection and its applications.
I. Fluxgate Technology: The Core Principle of DC Leakage Current Detection
1.Working Mechanism of Fluxgate Sensor
The magnetic field generated by the primary current Ip and the magnetic field generated by the output current Is on the compensation coil are equal in magnitude but opposite in direction. A square wave is generated by the coil and a square wave oscillation circuit. The output signal of the oscillation circuit is processed by a demodulation filter circuit to remove the signal generated by zero flux, and then the zero point and output signal amplitude are adjusted by a zeroing and amplification circuit. Because the magnetic core operates in a zero flux state, the non-linearity and remanence of the magnetic core have no effect on the accuracy of the sensor. Therefore, the fluxgate DC leakage current sensor has high accuracy and low nonlinear distortion, and is mainly used for the detection of small DC currents and leakage currents.
2.Technical Features of CHIPSENSE FR2V H00 Series Current Sensors
The FR2V H00 series is a current sensor independently developed by CHIPSENSE, based on fluxgate technology. It is specifically designed for DC leakage current detection and is suitable for applications such as charging piles, photovoltaic inverters, and DC power supplies. Its core parameters are as follows:
Key Advantages:
High Precision: Linearity error ≤ ±0.5%, meeting IEC62955's accuracy requirements for DC 6mA testing.
Wide Temperature Range: Operating temperature -40℃ to 70℃, suitable for outdoor charging station environments.
3.Insulation Safety: CHIPSENSE FR2V H00 series current sensors isolation withstand voltage 3kV, creepage distance 7.2mm, conforming to IEC 61800-5-1's reinforced insulation standard.
II. Charging Pile Applications: Typical Solutions for CHIPSENSE FR2V H00 Series Current Sensors
1. DC Leakage Detection for DC Fast Charging Piles
Pain Point: DC leakage in 800V high-voltage DC fast charging piles is difficult to detect. Traditional RCDs fail, easily leading to insulation faults or arcing risks.
Solution: Utilizing CHIPSENSE FR2V 0.05 H00 fluxgate current sensor, it detects ±75mA DC leakage with a response time of <500ms.
Charging Pile DC Leakage Detection System:
Action Logic: When the leakage current exceeds a threshold (e.g., 6mA), the current sensor of CHIPSENSE outputs a voltage signal to trigger the control unit to cut off power.
2. Composite Leakage Detection for Photovoltaic Charging Piles
Challenge: Composite wave leakage current (AC/DC hybrid) generated by photovoltaic inverters can easily lead to false alarms or missed detections.
Solution:
Using CHIPSENSE FR2V 0.01 H00 fluxgate current sensor to detect minute leakage currents of ±15mA, combined with a wide bandwidth response (DC~kHz) to achieve full waveform coverage.
Application Case: After adopting CHIPSENSE FR2V current sensor, a photovoltaic charging pile manufacturer reduced the false alarm rate of leakage current by 90%.
3. Insulation Fault Monitoring of Energy Storage Systems
Requirement: Insulation faults in energy storage battery packs need to be monitored in real time to prevent the accumulation of DC leakage current and potential fires.
Solution:
CHIPSENSE FR2V 0.30 H00 fluxgate current sensor monitors ±360mA leakage current, combined with a temperature compensation algorithm to ensure long-term stability.
Remote monitoring: Output voltage signals are uploaded to a cloud platform for predictive maintenance.
III. Product Advantages and Risk Warnings
1. Summary of CHIPSENSE FR2V Fluxgate Current Sensors Advantages
| Advantages | Detailed Description |
| Dedicated for DC leakage current applications | Designed specifically for DC systems, this technology solves the problem of traditional RCDs failing to detect DC leakage current. |
| High gain and accuracy | Theoretical gain up to 500V/A (CHIPSENSE FR2V 0.01 H00 current sensor), accurately detecting even minute leakage currents. |
| Low temperature drift | Zero-point temperature drift ≤±1.5mV/°C, requiring no long-term calibration. |
| Fast response | Response time of 500ms, meeting IEC 62955 requirements for DC leakage current disconnection time. |
| Easy integration | Standardized output interface (±5V), seamlessly integrating with charging pile control systems. |
2. Risk Warning and Installation Recommendations
Installation Precautions:
4.* The primary busbar of the sensor must be insulated to avoid the risk of electric shock ( CHIPSENSE Current Sensors are refer to IEC 61800-1 standard).
* Power Supply Voltage Stability: ±15V power supply, ripple <5%, otherwise detection accuracy will be affected.
Environmental Adaptability:
* Extreme high temperatures (>70℃) or low temperatures (<-10℃) may affect response time; heat dissipation or insulation measures are required.
Maintenance Recommendations:
* Regularly check the output voltage reference (zero-point voltage ≤ ±20mV). If the deviation is too large, recalibration is required.
IV. Industry Trends: Future Directions of Charging Pile Safety Technology
1. Intelligent Leakage Detection:
* Combining AI algorithms to analyze leakage wave-forms in real time, providing early warnings of insulation aging risks.
2. V2G (Vehicle-to-Grid) Safety:
* Charging piles need to support bidirectional energy flow; CHIPSENSE FR2V current sensors will be used for accurate detection of grid feedback current.
3. International Standard Evolution:
* IEC63053 (new version) will further tighten DC leakage detection requirements; fluxgate technology will become the mainstream solution.
V. Conclusion: Technology Drives Safety, Building a New Charging Ecosystem
CHIPSENSE FR2V H00 series fluxgate current sensor, with its high precision, low temperature drift, and dedicated DC leakage current detection features, provides a reliable DC leakage current detection solution for charging piles, photovoltaic inverters, and energy storage systems. Under the major trend of upgrading charging pile safety, fluxgate technology may become an industry standard. CHIPSENSE current sensor also uses this technology.
Recommendations:
For charging pile manufacturers: Prioritize integrating CHIPSENSE FR2V series current sensor into new product designs to ensure compliance with the latest standards such as IEC62955.
For operators: Regularly update leakage current detection algorithms and integrate them with remote monitoring systems to achieve predictive maintenance.
For standard setters: Accelerate the unification of international and domestic standards for DC leakage current detection to promote the healthy development of the industry.
CHIPSENSE is a national high-tech enterprise that focuses on the research and development, production, and application of high-end current and voltage sensors, as well as forward research on sensor chips and cutting-edge sensor technologies. CHIPSENSE is committed to providing customers with independently developed sensors, as well as diversified customized products and solutions.
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