Product details

Overview

The General High Voltage Reactive Power Compensation Switchgear (GKWB) for mining is suitable for non coal mining 10KV large and mediumsized industrial and mining enterprises and other substation distribution systems that require frequent adjustment of power factor due to load fluctuations. It can also be widely used in power systems, urban transmission stations, machinery, automobiles, railways, coal, coal, non-ferrous metals, chemical and other industries.

Technical data

Rated voltage (kV): 10

Rated frequency (Hz): 50

Power supply voltage: AC/DC220V+10% (external)

The primary principle wiring of the device is shown in Figure 2. This diagram can serve as the icon for this device, representing it in the electrical primary system wiring diagram.

Scope of application

This compensation cabinet is suitable for underground industrial production departments such as coal mines with no gas, no dust explosion sites, and non coal mines. It has a rated voltage of up to 10kV and is used in conjunction with the previous high voltage cabinet.

Functional Features

1. Voltage priority

Automatically switch capacitors according to voltage quality requirements. When the voltage exceeds the maximum set value, gradually cut off the capacitor bank until the voltage is qualified. When the voltage is lower than the minimum set value, gradually put the capacitor bank into operation while ensuring that it is not overloaded, so that the bus voltage is always within the specified range.

2. Reactive power automatic compensation function

Under the principle of voltage priority, the capacitor bank is automatically switched based on the reactive power of the load, so that the system is always in a state of minimum reactive power loss

3. Intelligent control function

Before automatically issuing action commands, first inquire about all possible out of limit values that may occur after the action, in order to reduce the number of actions.

4. The abnormal alarm function automatically locks and reorganizes the automatic control of the capacitor when the relay protection action of the capacitor control circuit refuses to move and the controller automatically locks.

5. Fuzzy control function

The implementation of comprehensive control principles when the system is at the high end of the qualified voltage range and in a specific environment is a difficult point in the design of this series of products. Frequent actions caused by various factors on site, such as configuration environment, power supply status, action time, and user restrictions on the number of actions, are the most concerning for users. The application of fuzzy control takes into account these many factors to reasonably solve this "blind spot".

6. Comprehensive protection function

Each device is equipped with switch protection (optional), overvoltage, undervoltage, overcurrent (short circuit) and zero sequence relay protection, double star unbalanced protection, fuse overcurrent protection, zinc oxide lightning arrester, grounding protection, quick break protection, etc.

Compensation cabinet function

1. Reactive power compensation device is a device that automatically or manually switches capacitor banks based on factors

such as system voltage and reactive power deficit, through comprehensive calculation, in order to improve voltage quality, improve

power factor, and reduce line loss.

2. This device is suitable for unmanned substations where the harmonic voltage and current meet the international allowable

values.

3. The digital reactive power compensation controller of the device is based on the nine zone diagram combined with fuzzy

control principle, and determines whether to switch the capacitor bank according to the requirements of voltage priority, load

reactive power, and limited switching times, so that the bus voltage is always within the standard range, ensuring no compensation

and minimizing losses. Within the allowable voltage range, switch the capacitor bank in place at once according to the reactive

power requirements of the load. Before investing in capacitors, budget for the voltage increase. If it exceeds the standard, reduce

the capacity investment or do not invest. When there is an abnormal situation, the controller issues a command to exit all capacitor

banks and sounds an alarm. After troubleshooting, manually release the alarm before returning to automatic operation mode.

Main components and functions of compensation cabinet

1. Discharge coil

1.1 Rated insulation level: meets the requirements of national standards.

1.2 Discharge performance: The capacitance meets the discharge requirements of the capacitor, meets the thermal stability requirements when discharging at the maximum discharge capacity, and meets the requirements of secondary load and voltage transformation ratio error. Reduce the residual voltage on the capacitor bank from the peak rated voltage to 50V within 5 seconds.

2. Dedicated reactive power compensation controller HYD-ZK

Switching principle: The control device automatically switches the capacitor bank according to the magnitude of reactive power while ensuring voltage quality, so that the bus voltage is always within the specified range.

The control device should be able to automatically optimize the control of the capacitor bank, and according to the principle of voltage priority, automatically switch the capacitors based on the required reactive power level

Keep the system in a state of no overvoltage, no compensation, and minimal reactive power loss. The control device should have the ability to automatically identify different operating modes, recognize the number of capacitor installation groups, and make intelligent predictions based on the capacity of each group. With the reasonable setting of parameters, it should not experience switching oscillations; Can achieve a control mode of cyclic switching, and can switch the capacitor bank first; It has manual and

automatic control functions, with automatic and manual interlocking. When manually switching, the controller automatically locks and exits the control; The control device has a self recovery function for system crashes, anti-interference capability, and a self check locking function for incoming calls.

The automatic switching control conforms to the following principles:

(1) Voltage priority control principle: When the voltage exceeds the set value, cut off the capacitor bank; When the voltage is set too low, the capacitor bank should be put into operation under the condition of ensuring no additional compensation.

(2) The principle of reactive power compensation control (i.e. the principle when the voltage is within the qualified range): reactive power under compensation is applied to the capacitor bank, and reactive power over compensation is applied to the capacitor bank; Before inserting the capacitor, inquire whether the voltage exceeds the high limit after insertion, and then decide whether to insert the capacitor (determined by software fuzzy theory analysis).

(3) Fuzzy control principle: preset the capacity of switching branches, monitor the active and reactive power of the system in real time, and switch the branches required by the load according to the set parameters.

3. Single protection fuse for capacitors

Model: Spray type fuse

3.1 Rated current: The rated current of the fuse of the fuse shall not be less than 1.43 times the rated current of the capacitor, and shall not be greater than 1.55 times the rated current of the capacitor.

3.2. Voltage resistance requirement: Meet the national standard requirements.

4. High voltage isolation switch

Used to control the input and output of the compensation cabinet, it is interlocked with the incoming switch cabinet of the compensation cabinet. When the compensation cabinet needs maintenance or debugging, it is isolated from the system and forms a clear disconnection point.

5. Vacuum contactor

Capacitive special contactor

The switching switch has the function of arbitrary switching; Capable of frequent switching; There is no obvious bouncing or welding of the contacts when opening the circuit; There should be no heavy impact when opening the switch; Capable of withstanding surge currents during closing.

6. Surge arrester for overvoltage protection

The technical requirements and operating conditions comply with the relevant provisions of GB11032 "AC gapless metal oxide surge arrester".

7. Reactor

7.1. Usage conditions: The usage environmental conditions are the same as those of the complete capacitor device.

7.2 Type: Dry type iron core reactor

Rated frequency: 50HZ Number of phases: Three phases Rated reactance rate: 6