Solusyon sa Proteksyon sa Feeder gamit ang mga Relay batas Microprocessor para sa Modernong Smart Distribution Networks

1. Introduksyon ug mga Punsal nga Kinahanglan​
   Ang pagtumong sa distributed energy resources (DERs) (tulad sa PV ug wind power) sa mga distribution network, kasama ang pagtaas sa demand sa mga user para sa reliability ug safety sa supply sa kuryente, nagpakita og severe nga mga hamon sa tradisyonal nga mga feeder protection scheme. Ang solusyon ini gihimo aron matubag ang sumala nga tatlo ka core challenges:

• ​Arc Flash Hazards:​​ Ang internal short circuits sa mga equipment tulad sa switchgear mahimong mogtrigger og highly destructive arc flashes, nga nagdudugay og panganib sa mga equipment ug personnel, nga nangangailigan og extremely fast response gikan sa protection system.
• ​High-Impedance Ground Faults:​​ Lalo na ang single-phase ground faults nga nahitabo sa rural areas o rehiyon nga may high soil resistivity, nga characterized sa low fault current, dili easy ma-detect niadtong reliable gikan sa tradisyonal nga zero-sequence overcurrent protection, nga nagpakita og panganib sa protection failure to operate.
• ​Epekto sa Integration sa Distributed Energy Resources (DERs):​​ Ang integration sa DERs magbabago sa direction sa power flow ug short-circuit current characteristics sa mga distribution networks, mahimong magresulta og protection maloperation (false tripping) o failure to operate, ug magintroduce og risk sa unintentional islanding.

Kini nga solusyon, batasan sa advanced microprocessor-based protective relays ug integrado sa multiple innovative algorithms, naghatag og comprehensive, rapid, ug reliable feeder protection alang sa modern nga distribution networks.

​2. Detalye sa Solusyon​
Ang atong feeder protection relay nag-adopar og modular design, integrado ang sumala nga core protection functions aron matubag ang gisulti nga mga hamon.

​2.1 Multi-Band Arc Flash Protection (AFP) Module​

• ​Teknikal nga Prinsipyo:​​ Nagamit og proprietary multi-band detection technology, simultaneously monitoring light intensity (tulad sa dedicated arc light sensors) ug ang rate of change of current (di/dt). Ang isang fault makumpirma as an arc flash lang kung parehas ang duha nga kondisyon – "intense arc light signal" AND "high-speed overcurrent characteristic (>10 kA/ms)" – adunay (logical AND operation). Kini nga dual criterion effective nga prevent ang maloperation gikan sa external light sources o switching overcurrents.
• ​Performance Advantage:​​ Features ultra-fast operating speeds, designed to minimize arc flash energy.
• ​Application Case:​​ Human jud ang deployment niining module sa medium-voltage distribution system sa usa ka large data center, nakamit kini nga total fault clearance time less than 4 milliseconds, representing a speed increase of over three times compared to traditional current-only protection schemes, significantly reducing equipment damage risk.

​2.2 High-Sensitivity Low-Current Ground Fault Protection Module​

• ​Teknikal nga Prinsipyo:​​ Nagamit og zero-sequence admittance method. Kini nga method involve real-time, precise measurement sa system's zero-sequence voltage (3U₀) ug zero-sequence current (3I₀), calculating the corresponding admittance value. Kini nga algorithm relatively insensitive sa variations sa system's capacitive ground fault current, effective nga distinguishing between normal capacitive current ug fault-induced resistive current, thereby accurately identifying high-impedance ground faults with resistance values up to 1 kΩ or higher.
• ​Performance Advantage:​​ Solves the issue of insufficient sensitivity in traditional protection schemes during faults through high transition resistance, greatly reducing risks of electric shock and fire.
• ​Application Case:​​ Sa usa ka pilot project within a rural network (characterized by high capacitive ground fault current and uneven line insulation levels), ang application niining teknolohiya increased the overall ground fault detection rate from 65% with traditional schemes to 92%, significantly enhancing power supply safety.

​2.3 Adaptive Anti-Islanding Protection Module​

• ​Teknikal nga Prinsipyo:​​ Aron matubag ang islanding risk introduced sa DER integration, kini nga module combined passive ug active detection methods.
• ​Passive Monitoring:​​ Continuously monitors abnormal parameters at the Point of Common Coupling (PCC), such as voltage frequency deviation (Δf > 0.5 Hz) ug phase angle jump (Δφ > 10°).
• ​Active Determination:​​ When passive monitoring indicators exceed set thresholds, it incorporates active methods like Active Frequency Drift to rapidly confirm an islanding condition.
• ​Performance Advantage:​​ Ensures rapid disconnection of DERs within a very short time frame (< 200 ms, compliant with grid code requirements) after islanding occurs, preventing hazards to grid equipment and maintenance personnel from unintended islanded operation.
• ​Application Case:​​ Validated in a microgrid project containing multiple PV arrays, this anti-islanding module achieved an accuracy rate of 99.7%. It effectively prevents islanding while minimizing unnecessary trips caused by normal grid disturbances, thereby improving the utilization rate of distributed energy resources.

​3. Summary sa Core Value​
Kini nga microprocessor-based protection solution, by integrating multiple intelligent algorithms, achieves:

• ​Enhanced Safety:​​ Maximizes the protection of personnel and equipment through millisecond-level arc flash protection and ultra-high-sensitivity ground fault protection.
• ​High Reliability:​​ Effectively addresses the complexities introduced by DER integration, accurately identifying islanding conditions and high-impedance faults, eliminating protection "blind spots".
• ​Rapid Restoration:​​ Enables fast fault clearance, facilitating rapid network self-healing, reducing outage duration, and improving power supply reliability.