Industrial Control Computer Low-current Grounding Fault Location Device

Operating System: Real-time Linux + RTOS. Utilizing a real-time Linux + RTOS (RTOS, Real-time Operating System) architecture, the system meets the operating system requirements of the State Grid/Southern Power Grid for the line selection device, while also considering the system's stability, security, and real-time performance requirements.

Hardware Foundation: Big Data + Powerful Computing. Employing a large-scale FPGA, the system implements 84 channels, synchronous 16-bit AD sampling, with a sampling frequency of 50KPPS, providing a reliable data foundation for grounding and other related fault handling. A high-performance multi-core heterogeneous processor (dual floating-point DSP C66x + dual ARM), high speed (DSP: 750 MHz; ARM: 1500MHz), and large-capacity high-speed memory provide sufficient computing power for data processing.

High Accuracy of Fault Selection: Based on big data and powerful computing capabilities, the device employs steady-state and transient algorithms, a fault selection learning algorithm, and effective domain fault selection technology. Verified using a "physical simulation experimental system," it can accurately identify various complex grounding fault types, including metallic grounding, transition resistance grounding with less than 8000 ohms, and intermittent arcing grounding.

Complete Fault Selection and Protection Logic: The device features a complete grounding fault handling logic, achieving the grounding protection goals of accurate identification of instantaneous faults, rapid isolation of permanent faults, and rapid restoration of power supply to non-faulty lines.

Powerful Functions: Includes fault selection, tripping (closing), post-accelerated tripping, alternating tripping (leak testing), dual-channel protection, phase detection, PT disconnection detection, fault recording, and fault statistical analysis.

Scalability: The device's hardware design allows for expansion of control functions, enabling active fault selection schemes similar to those using parallel resistance in arc suppression coils.

Fault Selection Function: The device features a grounding fault selection function. When a single-phase ground fault occurs in the system, the device can make an accurate judgment based on the collected signals, select the faulty line, and display the name (number) of the grounded line and busbar. It automatically resets after the ground fault disappears.

Trip (Close) Function: The device has a ground fault protection trip (close) function, which can be implemented by connecting to the protection trip (close) circuit. The device's trip (close) function can be enabled/disabled and the delay function can be independently set for different lines.

Rotational Handling Function: The device has a rotational handling function. After a selected line trip fails, the rotational handling function can be directly activated according to the device settings, operating sequentially until the faulty line is disconnected, ensuring the accuracy of line selection. When the protection sensitivity is insufficient (line selection protection setting > 3U0 > rotational handling setting), the rotational handling function can be activated with a delay (long-time rotational handling). This function can be enabled/disabled, the delay can be set, and whether each line participates in rotational handling can be set independently. The rotational handling (leakage testing) strategy can be set, with both fixed and automatic rotational handling modes.

**Accelerated Tripping Function:** The device features accelerated tripping. When a selected line trips successfully but recloses to a permanent fault (if the line reclosing switch is engaged), the device can accelerate the tripping to disconnect the faulty line. This function can be enabled or disabled.

**Phase Detection Function:** The device has a single-phase ground fault phase detection function, accurately identifying the faulty phase.

**PT Disconnection Detection Function:** The device has a PT disconnection detection function, distinguishing between primary and secondary PT disconnections. A line selection strategy can be set for disconnection conditions.

**Ferromagnetic Resonance Alarm Function:** The device has a ferromagnetic resonance alarm function. When ferromagnetic resonance occurs in the system, the device can accurately identify it and issue a ferromagnetic resonance alarm signal.

**Fault Statistics Function:** The device has the function of statistically analyzing the number of instantaneous and permanent groundings for each line, providing a basis for analyzing the line's operating status.

**Operating Condition Adaptive Function:** The device can make judgments based on changes in field operating conditions, such as changes in the position of sectionalizing switches or tie switches in ring network structures, ensuring the correct operation of the line selection device.

Self-test function: The device has an online automatic detection function. During normal operation, if a single electronic component in the device fails (excluding the output relay), it will issue an abnormal signal without causing malfunction.

Fault recording function: The device has a fault recording function. When a single-phase ground fault occurs in the system, it records data for 80ms before the fault occurs and 120ms after the fault occurs, as well as data for 80ms before the initial line selection trip and 120ms after the initial line selection trip. The recording resolution is 120 points per cycle. The recording file adopts the standard COMTRADE99 format and supports extraction of the recording file via Ethernet port and debugging interface.

Communication function: The device communicates with the substation automation system and remote control equipment using protocols conforming to DL/T 860 substation communication network and system (IEC 61850) and the "DL/T860 Engineering Implementation Specification for Relay Protection Information System Master Station-Substation".

Time synchronization function: The device has a time synchronization function (including B-code time synchronization and network time synchronization), with an error of no more than 1 millisecond. If all time synchronization signals are lost, the device's own clock will be used, with a 24-hour error of no more than ±5 seconds. The internal clock chip will continue to operate even when the device is powered off.

Fault Simulation Function: The device can simulate single-phase ground fault alarm signal output, trip (close) relay signal output, and communication soft message output, facilitating joint debugging and testing.

Dual-Channel Protection Function: The device's zero-sequence voltage sampling circuit uses a dual A/D or dual-channel structure to avoid malfunctions caused by the failure of a single A/D converter.

We have professional technicians assigned to each stage of our pre-sales, sales, and after-sales service to ensure fast and professional service response. The company provides a 24-hour online consultation hotline, answering customer questions about product performance, functions, and pricing through telephone, email, and online customer service. We also provide customized solutions based on customer needs and offer remote diagnostics, guidance, and maintenance services for faulty products. We promise our users: to adapt to the market with high-quality products, to meet needs quickly, and to satisfy customers with thoughtful service.