The assembled shunt capacitor is mainly used for reactive power compensation in 10kV and 35kV power frequency power systems. To improve the power factor of power grid, reduce line loss, improve voltage quality, and give full play to the efficiency of power generation and power supply equipment. Because the product adopts a collective structure, it has small floor area, convenient installation and maintenance, high reliability, and low operating costs, especially suitable for outdoor centralized compensation of large substations and urban power grid reconstruction.

Main product features:

1. See Attached Table 1 (10KV), Figure 1-4 for the main parameters and overall dimensions of the assembled shunt capacitor; Attached Table 2 (35), Figure 9-12. The complete arrangement of capacitors is flexible and diverse, so only some typical arrangement forms are provided for reference, see Figure 5-8 and Figure 13-15. The size of the site in the drawing has margin. Under the condition of ensuring the safe distance, users can make appropriate adjustments, and also choose other layout methods according to their own conditions.

2. Steady state overvoltage

The continuous operating voltage of the capacitor is 1.00Un, and it can operate for corresponding time under the stable overvoltage specified in Table 1. The overvoltage value that can be tolerated by the capacitor without significant damage depends on the duration, the total number of times and the temperature of the capacitor. The overvoltage higher than 1.15Un in Table 1 is determined on the premise that it does not exceed 200 times in total during the life of the capacitor.

3. Operating overvoltage and overcurrent

When the capacitor is switched on or off with the switch without re-breaking and bouncing, the first peak value may not be greater than 2 times the applied voltage (root mean square value), and the duration shall not be greater than 1/2 cycle of transition overvoltage. The corresponding peak value of transition overcurrent may reach 100In. In this case, 1000 operations per year are allowed.

4. Steady state overcurrent

Capacitors are allowed to operate under a stable overcurrent with an effective value of 1.3In due to voltage rise and harmonics. For capacitors with the maximum positive deviation of capacitance, this overcurrent is allowed to reach 1.43In.

5. Power frequency plus harmonic overvoltage

If the capacitor operates for a long time at a voltage not higher than 1.10Un, the voltage peak including all harmonic components shall not exceed 1.2Un.

6. Capacitance deviation

The deviation between the capacitance of the capacitor and its rated value shall not exceed 0~+5%, and the ratio of the maximum value to the minimum value of the measured capacitance of any two phases of the three-phase capacitor shall be ≤ 1.02.

7. Tangent value of dielectric loss angle of capacitor

Full-film dielectric structure capacitor: tgd is not greater than 0.0004.

8. The internal oil temperature of the capacitor shall not exceed 65 ℃ when it operates continuously at rated capacity within the operating ambient temperature.

9. Creepage distance of outlet bushing: 10kV, not less than 410mm; 35kV not less than 1200mm

10. See Table 2 for the torque that the conductive rod can bear.

The altitude of the installation site shall not exceed 1000 meters. Note: For capacitors used in areas with altitude higher than 1000 meters, please specify when ordering.

Operating ambient temperature

A. Products impregnated with phenyldimethylphenyl ethane: - 25 ℃~+45 ℃.

B. Products impregnated with benzyl toluene: - 40 ℃~+45 ℃.

Seismic strength: 0.25g in horizontal direction, 0.125g in vertical direction.

There is no serious corrosive gas or steam to metal, no conductive dust, and no severe mechanical vibration around.

1.1 Assembled shunt capacitor is mainly composed of internal capacitor unit, frame, box, oil compensator and outlet bushing. All elements in the capacitor unit are of exposed foil structure. Each element string has a fuse. When one element breaks down, other intact elements will discharge it, so that the fuse can fuse quickly in millisecond, and the faulty element can be removed, so that the capacitor can continue to operate normally. The capacitor unit is installed on the frame, and makes appropriate electrical connection according to different voltage and capacity, and is connected with the outlet bushing on the box cover through the wire for the connection of incoming and outgoing lines and discharge coils. The discharge coil can be placed on the side wall or cover of the capacitor box according to the user's requirements.

1.2 The box is welded by steel plate, and the box cover is equipped with outlet bushing, metal expander and pressure release device. The two sides of the tank wall are welded with lifting hooks (large capacity products with more than 8000kvar are equipped with sheet radiators), and the lower part of one side of the tank wall is equipped with oil injection valve, oil sampling valve and M16 grounding bolt.

1.3 Metal expanders are used for all specifications of assembled capacitors to compensate the volume change of oil in the tank due to temperature change. The metal expander is welded from stainless steel sheet. Due to the fully sealed structure, it is not necessary to filter and replace the cooling insulating oil in the tank regularly.

1.4 Capacitor reactive power compensation device is generally composed of high-voltage switchgear, series reactor, zinc oxide arrester and its recorder, discharge coil, disconnector, grounding switch, collective capacitor, etc. When double star connection is adopted, current transformer for neutral point current unbalance protection is also included.

1.5 The series reactor is connected in series in the capacitor circuit to suppress higher harmonics and limit the closing inrush current.

A. The reactor can be configured according to Xl/Xc=4.5%~6% when it is used to suppress 5th and above harmonics.

B. The reactor can be configured according to Xl/Xc=12%~13% when it is used to suppress the third and above harmonics.

C. When only used to limit the closing inrush current, the reactor can be configured as Xl/Xc=0.5%~1%.

1.6 The discharge coil is connected at both ends of the capacitor in parallel. When the capacitor is disconnected from the power supply, the residual voltage at both ends of the capacitor can be reduced from Un to below 50V in 5 seconds.

2 Features

2.1 Assembled shunt capacitor adopts the design scheme of small element plus internal fuse. The broken element is disconnected by the internal fuse, which only makes a small change in capacity. The capacitor can continue to operate, extending the maintenance period and improving the operation reliability.

2.2 Assembled shunt capacitor is composed of multiple capacitor units with iron shell. The capacity, primary connection mode and relay protection form can be determined according to user needs, which is convenient and convenient.

2.3 The assembled shunt capacitor combines multiple capacitor units in a box, so it has a small floor area compared with the ordinary frame capacitor bank. It can be used for outdoor installation without building houses, which can greatly save capital construction investment; At the same time, the installation is convenient, and the maintenance and inspection of the capacitor bank only need to be carried out on one capacitor, which greatly reduces the workload and cost of operation and maintenance.