HYHG Juyou overvoltage protection cabinet
Overvoltage 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 system's electrical equipment and greatly increase the failure rate. Abnormal overvoltage may be external or self-generated within equipment or devices.
The intrusion path of external overvoltage can be through wires and circuit conduction, or 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 overvoltage can be divided into lightning overvoltage, operating overvoltage, ferromagnetic resonance overvoltage and solitary light grounding overvoltage according to its different causes.
There is currently no complete protection scheme for these overvoltages, and accidents such as cable blasting, motor insulation breakdown, arrester explosion, and voltage transformer burnout often occur. The reasons for such accidents are not only related to the performance of the overvoltage protector products installed in the system, but also the complexity of the system itself has an important impact on overvoltage. For different systems, when using overvoltage protection products, it is necessary to consider the type of system transmission lines, the network structure of transmission and distribution lines, 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 comprehensively suppress various types of system overvoltage, such as lightning arresters, combined overvoltage protectors, arc suppression coils, arc suppression devices of various principles, and PT harmonic eliminators, etc. Although various overvoltage protection products are installed in these systems, the system overvoltage cannot be completely and effectively suppressed because the product protection characteristics are not well matched, especially when overvoltage protector products from different manufacturers are installed in the same system.
In view of the current situation of overvoltage prevention and control in medium and low voltage systems, our company independently developed and produced the Juyou overvoltage protection cabinet (referred to as: overvoltage protection cabinet, model HYHG). This device can make up for the shortcomings of overvoltage protection components and devices in the system and improve the overvoltage protection level of the system.
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 large energy generated by overvoltage. It can greatly reduce the residual voltage value, eliminate a large amount of energy generated when the system is over-voltage, suppress the system over-voltage, and effectively ensure the safety of the device itself.
This product adopts unique technology that can simultaneously eliminate resonant overvoltage, disconnection overvoltage, etc. in the system, and comprehensively eliminate the dead zone of 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 occurs PT disconnection, resonance, metal grounding, arc grounding and other phenomena. The intelligent microcomputer device uses the high-speed and repetitive data processing capabilities of DSP to analyze and judge, promptly and accurately determine the fault type of the system, perform corresponding device actions, display the fault type, and output the corresponding switching contact signal for alarm.
The protection cabinet uses microcomputer technology for power grid harmonic elimination, and uses the computer's fast and accurate data processing capabilities to implement Fourier analysis, with accurate frequency selection. By collecting the PT three-phase voltage and the open triangle voltage, the frequency components during grid resonance can be quickly analyzed and accurately judged.
If the system resonates, depending on the frequency, the controller issues different instructions to activate the resonance elimination circuit to quickly eliminate the resonance. The device can store and record various technical parameters in the fault state to facilitate accident analysis. It can be widely used in power plants, substations, and power systems of large factories and mines such as steel, coal, and petrochemical industries.
This device has RS485 and RS5232 interfaces and is equipped with standard MODBUS communication protocol to realize long-distance data transmission with the user's computer monitoring system.
This product is designed to provide a comprehensive overvoltage protection solution based on the user's system needs. Therefore, when designing, the user needs to provide the system structure and parameters; eliminate various overvoltage protection dead zones in the system and absorb large overvoltage energy in the system;
It replaces the PT cabinet and has the ability to judge and alarm the faults that occur in the system. It is cost-effective, the device has a wide range of applications and is easy to put into operation. When the single-phase ground fault of the system is eliminated, it can effectively limit the impact inrush current through the PT and protect the safety of the PT and fuses.
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. Intelligent switch HYNG-10;
7. Microcomputer integrated controller HYXQT. When the system is running normally, it should be able to indicate the system voltage, be able to judge various voltage faults in the system and operate reliably. The device is equipped with a self-test 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. Measurement system voltmeter 6L2-V/12kV.
Overvoltage protection cabinet
/0.1/
