Product Overview

In power systems, ferroresonance occurs frequently, producing overvoltage during resonance, which seriously threatens system safety. Ferroresonance overvoltage can occur in any system from 3 to 220 kV, especially in networks at 35 kV and below, where nearly all internal overvoltage incidents are caused by ferroresonance. Overvoltages caused by ferroresonance last a long time and may even persist for an extended period. During subharmonic resonance, overvoltage is generally not high, but the PT current is large, which can cause PT overheating and explosion; during fundamental and harmonic resonance, the current is usually not large, but the overvoltage is very high, often damaging equipment insulation and causing serious accidents.

The microcomputer-based resonance suppression device is an intelligent power resonance elimination device developed by our company. It’s easy to use, requires no maintenance, and can quickly eliminate ferroresonance at various frequencies with high accuracy. At the same time, it can print or transmit relevant information to the upper monitoring system via a communication interface based on user needs, making it suitable for unmanned substations.

Features

● Suitable for various voltage levels of distribution networks.

● Can monitor four bus sections.

● Quickly eliminates ferroresonance at characteristic frequencies such as one-third, one-half, power frequency, and triple frequency.

● Can distinguish between external overvoltage, ferroresonance, and single-phase grounding.

● Uses high-power, contactless resonance suppression components for fast and reliable suppression.

● Provides a set of passive alarm nodes.

● Can display fault reports (type, time, voltage, and frequency) when a fault occurs.

● Optional mini printer can print fault reports immediately.

● Communication interfaces can be configured to send relevant information to the upper monitoring system.

● Stores the ten most recent fault records, with data retained even during power loss.

● Hardware watchdog circuit prevents system crashes.

● Complete self-check functions.

● User-friendly interface, simple operation, full Chinese menu, and rich, intuitive display.

Technical Specifications

● Power supply: AC/DC 220V (please specify when ordering if special requirements), power consumption <20W.

● Alarm node capacity: AC 250V, 5A; DC 30V, 5A.

● Communication interface: RS232/485 (choose one, please specify when ordering), baud rate 1200~9600 bps.

● Communication protocol: built-in three protocols CM90, CDT, MODBUS.