HYHXB intelligent arc suppression integrated protection cabinet
The intelligent arc-extinguishing integrated protection cabinet produced by our company has functions such as arc-extinguishing, harmonic elimination, line selection and over-voltage protection, and the corresponding functions can be selected according to needs. It is suitable for 3~35 kV three-phase non-directly grounded power systems to limit various types of overvoltage, arc grounding overvoltage, resonance overvoltage, and operating overvoltage to improve the safety of power grid operation and power supply reliability.
★Suitable for 3~35 kV medium voltage power system;
★Suitable for three-phase non-directly grounded power systems such as neutral point ungrounded systems and neutral points grounded through arc suppression coils or neutral points grounded through high resistance;
★Applicable to both power grids dominated by cable lines or hybrid grids of cables and overhead lines, and also suitable for grids dominated by overhead lines.
★When a single-phase ground fault occurs in the system, the faulty phase can be directly grounded in about 30ms.
★When a PT disconnection fault occurs, the device outputs a contact signal so that the user can block the relay protection that may malfunction due to PT disconnection.
★After the product operates, the panel displays the fault type (PT disconnection, metal grounding or arc grounding) and phase, and outputs a passive switching contact signal at the same time. The product is equipped with an RS485 interface, which can transmit data remotely according to the communication protocol provided by the user.
★The product can limit various overvoltages occurring between phases or between phases and ground to about 35 times.
★The voltage transformer in this product can provide voltage signals to measuring instruments and relay protection, and can replace conventional PT cabinets.
★This product can be configured with automatic line selection function according to user requirements, and can recall 20 layers of ferromagnetic resonance information in the system and 12 layers of grounding information. This product selects lines based on the dual criteria of "relative amplitude" and "relative phase" of the line's zero-sequence current, overcoming the influence of system operating mode changes, grounding resistance size and line length on line selection.
★This product can be configured to eliminate (eliminate) resonance (vibration) according to user requirements.
★High-capacity three-phase combined overvoltage protector (KHYD)
It is a special large-capacity overvoltage protection device currently developed by our company. It plays the role of limiting system overvoltage. It is different from the general zinc oxide arrester (MOA) structure and has the following main advantages:
1. The discharge voltage value of the overvoltage protector is equal under various voltage waveforms, and the protection performance is not affected by the overvoltage waveform;
2. The instantaneous discharge value of the overvoltage protector is similar to the residual voltage, without clipping, which is beneficial to protecting the inter-turn insulation of winding-type equipment;
3. The overvoltage protector adopts a four-star connection method, which can greatly reduce the phase-to-phase overvoltage. Compared with conventional lightning arresters, the reliability of protection is greatly improved. The overvoltage protector is the first device in this product to limit various types of overvoltage. It limits the voltage to a safe range before the contactor operates.
★High-voltage vacuum quick contactor (JZ) that can be controlled by phase separation
High-voltage vacuum quick contactor can complete opening and closing in 8~12ms. One end of the vacuum contactor is connected to the busbar, and the other end is directly connected to the ground. During normal operation, the contactors are in a disconnected state and are closed under the control of the microcomputer controller ZK. The operating circuits of the vacuum contactors of each phase are mutually locked. When any one of the phases is closed and the bus of that phase is grounded, any one of the other two phases will no longer operate. The function of the contactor is to quickly transform the unstable arc grounding into a stable metallic direct grounding when an arc grounding occurs in the system, thereby protecting the equipment from damage.
★Multifunctional microcomputer controller ZK (including voltage signal converter)
Controller ZK is the core control component of this device. It is based on the U provided by PT.to the,Ubo、Uco、UoThe signal is used to determine the fault phase and fault type (PT disconnection, metal grounding and arc grounding), and the high-voltage vacuum contactor is controlled in a preset manner. All functions of the microcomputer controller are automatically executed without manual operation, and operation and maintenance are simple. The microcomputer controller uses secondary power supply technology to resist various electromagnetic interferences. All interfaces adopt optical/electrical isolation, which can eliminate interference from the power supply and primary system to the controller. The controller is also equipped with a Watchdog self-reset circuit, which can realize automatic reset of the device and completely avoid various electromagnetic interference from the outside world. The microcomputer controller uses dual processors as processing units, which can simultaneously complete comprehensive control of arc suppression, harmonic elimination and line selection, and is fast. It also has voltage transformer high-voltage fuse blowout alarm and voltage transformer secondary voltage signal circuit failure alarm functions. The microcomputer controller can measure the voltage of the system and display it in digital form. The microcomputer controller is equipped with an RS485/232 communication interface, which can report system fault information and device working conditions to the control center. The microcomputer controller has a memory that can store the system's fault information (including fault type/fault time, etc.) for a long time. The user can query the system's fault records as needed. The microcomputer controller has designed a line selection module that can complete single-phase grounding line selection for multiple outgoing lines (32 circuits per bus section). It adopts the original "vector sudden change method" line selection principle, and can accurately select the grounding line no matter what nature of grounding occurs in the system.
★ ★ High voltage current limiting fuse assembly FUR
It is the back protection device of the entire product. It can prevent misjudgment due to miswiring or product failure, which may lead to phase-to-phase short circuit. It has the following functions:
1. Large breaking capacity, up to 63kA; fast breaking, breaking time is generally 1~2ms;
2. The current limiting effect is good, and the fault phase current can be limited to less than 1/5 of the maximum short-circuit impulse current;
3. The breaking arc voltage is low. During the fuse breaking process, the arc voltage is very low, and the arc voltage will be further reduced when used in a system with a voltage lower than the rated voltage. Therefore, a 12kV fuse can be used in a 7.2kV system without the risk of damaging the system insulation. When a single-phase grounding occurs in the system, the voltage Ua across the open triangle of the voltage transformer PT immediately changes from low potential to high potential, putting the controller into operation. It can convert the three-phase high-voltage signal of the system voltage transformer into a voltage signal (Ua Ub Uc) and neutral point signal (Uo）。
★High voltage isolation switch GN
The connection point of the main busbar of the power grid is used for switching during installation and maintenance of this device. It can also be changed to an isolated handcart according to the needs of the user.
★CT and ground ammeter
When the device is in operation, the ground capacitance current of the system can be read more accurately through the ground ammeter.
The product has fast action speed and can operate quickly in 30~40ms, which greatly shortens the duration of single-phase grounding arc;
The arc can be extinguished immediately after the product is activated, and it can effectively limit the arc ground overvoltage. After the product is activated, a capacitive current of 200A is allowed to pass continuously for at least 2 hours. The user can deal with the faulty line after completing the switching operation of transferring the load. The protection function of this product is not affected by the scale and operation mode of the power grid;
This product uses the characteristics of the largest zero-sequence current mutation of the fault line before and after the arc is extinguished to select the line, which can greatly improve the accuracy of line selection.
When the system is operating normally, the open delta voltageU△It is very small, and the controller panel displays "operation" and can display the voltage of each phase. whenU△When it changes from low level to high level, it indicates a system failure. At this time, the microcomputer controller ZK immediately starts the interrupt; the fault type and phase are judged according to whether the PT secondary output voltage exceeds the given value:
If it is a single-phase PT disconnection fault, the fault phase and disconnection signals will be displayed on the product panel, and a passive switching contact signal will be output;
If it is a single-phase arc ground fault, the fault phase and grounding type signals will be displayed on the product panel. At the same time, a closing command will be sent to the vacuum contactor of the fault phase, and a passive switch contact signal will be output. The fault phase will be directly grounded. The ground arc will be immediately reduced to zero due to the arc voltage at both ends, and the arc will be completely extinguished.
If used in a power grid dominated by overhead lines, the vacuum contactor will automatically open 5 seconds after the product operates. If it is a transient ground fault, the system will return to normal. If it is a permanent ground fault, the vacuum contactor will no longer open after the product operates again.
The working principle of the small current line selection device is that before and after the ground arc is extinguished, the magnitude and direction of the zero-sequence current of the non-fault line are basically unchanged, while the zero-sequence current of the fault line changes from the ground capacitance current of the entire system to the ground capacitance current of this line, and the direction changes by 180°. Only the zero-sequence current of the fault line has the largest change before and after the arc is extinguished, so the best use The small current line selection device designed based on the principle of the large increment method solves the problem of inaccurate line selection or even line selection failure of conventional line selection devices when the arc is grounded, and is not affected by the arc coil.
Environment: Temperature: -40℃~+40℃, monthly average relative humidity not greater than 90%
Altitude: ≤2000m, (special design is required for heights above 2000m)
Using environment: There must be no explosive mixtures such as dust, gas, and flue gas.
Generally, it is packaged in wooden boxes, and the base of the cabinet should be fixed on the bottom plate of the packaging box.
It is not suitable for long-distance transportation on grade three or above highways. If necessary, the packaging can be dismantled. Important components should not be transported by road as much as possible.
When not in use for a long time, it should be stored in a dry and ventilated warehouse and should not be stored outdoors for a long time.
Our company is responsible for drawing design and parameter selection according to the user's requirements. After the equipment is assembled and debugged, it can only be shipped out of the factory after passing the inspection by professional inspectors. If the user needs it, our company can be responsible for on-site installation guidance and debugging services, and the user will provide necessary cooperation and assistance.
When the equipment is working normally, maintenance and repair are not required. Only after the product operates, check whether the fuse striker pops out.
As long as the user abides by the rules of storage and use, if the product is damaged and fails to work properly due to quality reasons within 12 months from the date of installation and use, or 18 months from the date of shipment, the manufacturer will replace or repair it free of charge for the user.
Our company implements lifelong maintenance of equipment and provides it at preferential prices for a long time.Spare parts.
1. The user should provide relevant system rated voltage and system maximum single-phase grounding capacitance current as the basis for the design of this product.
2. The size of the cabinet can be finalized only after it is designed by our company's engineers and signed and confirmed by the user.
3. The user should clarify the functions of the device (including basic functions and optional functions). If there are any special requirements, they should be put forward when ordering.
4. If you need other additional accessories or spare parts, please indicate the required names, specifications and quantities when ordering.
