HYHG Juyou Overvoltage Protection Cabinet

1. Product overview

Over-voltage phenomenon is very common in my country's 3~35kV power supply system. If there are no preventive measures, overvoltage surges may occur at any time, which will cause insulation breakdown of the electrical equipment of the system and greatly increase the failure rate. The abnormal overvoltage may be external or self-generated inside the equipment or device.

The intrusion path of external intrusion voltage can enter through wire and circuit conduction, and it can also invade through electrostatic induction and electromagnetic induction. The occurrence of overvoltage may be regular and periodic, but more often it is random, so it is difficult to accurately grasp in most cases. Abnormal overvoltages can be divided into lightning overvoltages, operating overvoltages, ferromagnetic resonance overvoltages, and solitary light grounding overvoltages according to their different causes.

At present, there is no complete protection scheme against these overvoltages, and accidents such as cable blasting, motor insulation breakdown, lightning arrester explosion, and voltage transformer burnout often occur. The reason for such accidents is not only related to the performance of the overvoltage protector installed in the system, but the complexity of the system itself also has an important impact on overvoltage. For different systems, when using overvoltage protection products Need to consider the type of system transmission line, the network structure of the transmission and distribution line, the nature of the load and the grounding method of the system, etc.

For such a complex system, it is difficult to use one or several overvoltage protection products in isolation to fully suppress various types of system overvoltages, such as lightning arresters, combined overvoltage protectors, arc suppression coils and various principles of suppression. Arc device and PT resonance eliminator, etc. Although a variety of over-voltage protection products are installed in these systems, the protection characteristics of the products cannot be matched well, and the system over-voltage cannot be completely and effectively suppressed. This is especially true when the same system is equipped with over-voltage protectors from different manufacturers. .

In view of the current situation of overvoltage prevention in medium and low voltage systems, our company independently developed and produced Juyou overvoltage protection cabinet (abbreviation: overvoltage protection cabinet, model HYHG), which can compensate for the overvoltage protection components and devices in the system. Insufficient, improve the overvoltage protection level of the system.

2. Working principle

Juyou overvoltage protection cabinet adopts special large-capacity overvoltage suppression components developed by our company, which can effectively smooth the rising front of overvoltage, suppress, filter and eliminate voltage spikes, and can withstand the super energy generated by overvoltage. It can greatly reduce the residual voltage value, eliminate the large amount of energy generated when the system is overvoltage, and suppress the system overvoltage, which effectively guarantees the safety of the device.

The product adopts a unique technology, which can eliminate the resonance overvoltage and disconnection overvoltage in the system at the same time, and completely eliminate the dead zone of the system overvoltage.

When the overvoltage protection cabinet is operating normally, the intelligent microcomputer controller in the cabinet continuously detects the secondary voltage signal provided by the PT in real time. Once the system has PT disconnection, resonance, metal grounding, arc grounding and other phenomena. The intelligent microcomputer device uses the DSP's high-speed and repetitive data processing capabilities to analyze and judge, timely and accurately determine the fault type of the system, execute the corresponding device action, display the fault type, and output the corresponding switch contact signal for alarm.

The protection cabinet uses microcomputer technology to eliminate harmonics in the power grid, and uses the computer's fast and accurate data processing capabilities to achieve Fourier analysis, and its frequency selection is accurate. Through the collection of the PT three-phase voltage and the open delta voltage, the frequency component of the grid resonance can be quickly analyzed and accurately judged.

If the system resonates, according to different frequencies, the controller will issue different commands to enable the resonance elimination circuit to quickly eliminate resonance. The device can store and record various technical parameters in the hidden state, which is convenient for accident analysis and can be widely used in power plants. , Substations and power systems of large factories and mines such as steel, coal, petrochemicals, etc.

This device has RS485 and RS5232 interfaces, is equipped with a standard M0DBUS communication protocol, and realizes long-distance data transmission with the user's computer monitoring system.

3. Product features

This product is designed to provide a comprehensive overvoltage protection scheme according to the user's system requirements. Therefore, when designing, the user needs to provide the system structure and parameters; eliminate the system's various overvoltage protection dead zones, and absorb the system overvoltage energy;

It replaces the PT cabinet and has the faults in the system for judgment and alarm display. It is cost-effective, has a wide range of devices and is easy to put into operation; when the system single-phase grounding fault is eliminated, it can effectively limit the surge current through the PT and protect the PT and fuse. Security issues.

4. The structure and appearance of the product

5. The main components of the product

Examples of main components of 12kV Juyou overvoltage protection cabinet:

1. Isolating switch: GN19-10C/630 (fixed) VS1-10C (mobile);

2. Voltage transformer: JDZJ-10, transformation ratio 10//0.1//0.1/;

3. High voltage fuse: XRNP-12/0.5A-50kA

4. High-voltage current-limiting fuse: XRNT-12/10A-50kA;

5. Large capacity overvoltage protector: KHYD5W-17F/45N, 2ms square wave 800A;

6. Smart switch HYNG-10;

7. Microcomputer integrated controller HYXQT. When the system is operating normally, it should be able to indicate the system voltage, be able to judge the various voltage failures of the system and operate reliably. The device is equipped with a self-check function. When the device itself fails, it should be able to alarm: at the same time, the device should have a harmonic elimination function ;

8. Measuring system voltage meter 6L2-V/12kV.

6. Product model and parameters

7. Product application scheme

Overvoltage protection cabinet