Product introduction

HKK-SVGC low-voltage reactive power compensation device is a new reactive power compensation device that combines thyristor switching capacitor TSC and static var generator HKK-SVG, which can quickly, continuously and accurately adjust electric reactive power;

The device solves the contradiction between the traditional reactive power intermittent compensation and the high cost of pure active static var generator HKK-SVG. The effective combination of the two enables compensation switching without inrush current, fast response speed, and compensation accuracy. improve;

HKK-SVGC compensation equipment is a new reactive power compensation device with high cost performance jointly developed by Shanghai Huakun Electric Co., Ltd. and Shanghai Jiaotong University on the basis of the research and development technology and experience of active dynamic reactive power compensation device. The device can quickly compensate for reactive power, collectively compensate for three phases, and separately compensate for single-phase, thereby improving the stability of the power grid; suppressing busbar voltage flicker, compensating for unbalanced loads, and improving power factor.

As a new combination, HKK-SVGC is being widely used in petrochemical, metallurgy, electric power, coal, electrified railways, wind power plants and other places with large shock loads and in the field of large-capacity motor industries. It will definitely play a role in improving power quality. It has become an excellent reactive power compensation equipment for users. This product is mainly used to improve and improve the following indicators of power supply quality:

a. Voltage stability of the receiving terminal

In many places where electricity is used, due to the large load capacity and no large reactive power support, it is easy to cause the grid voltage to be low, and even voltage collapse accidents occur. The application of HKK-sVGC realizes the function of fast and precise adjustment of reactive power, stabilizes the voltage on the load side, and improves the quality of power consumption.

b. Improve power factor and reduce line loss

A large number of loads in the power system, such as asynchronous motors, electric arc furnaces, rolling mills and large-capacity rectifier equipment, will generate a large amount of reactive power during operation, and transformers and line impedances in the transmission and distribution network will also generate a certain amount of reactive power. Power factor is reduced; the reduction of power factor will increase the loss and voltage drop of the power supply line, resulting in a reduction in the utilization rate of power generation, transmission and power supply equipment. The use of HKK-SVGc reduces line loss and saves electricity expenses.

c. Suppress voltage fluctuation and flicker

The voltage fluctuation and flicker are mainly caused by the drastic change of the load; the drastic change of the load causes the current to fluctuate violently, which makes the power grid voltage flicker at the receiving end. Typical loads that cause voltage flicker include electric arc furnaces, rolling mills, and electric locomotives. HKK-SVGC can quickly track the changing current to compensate for voltage fluctuation and flicker caused by load changes.

d. Suppress three-phase unbalance and quickly compensate negative sequence current

In the distribution network, due to the unreasonable power distribution and electricity consumption, there are a large number of three-phase unbalanced loads, such as traction loads of electric locomotives and AC arc furnaces. At the same time, the imbalance of three-phase impedance of transmission and distribution equipment such as lines and transformers will also lead to voltage imbalance problems. HKK-SVGC enters the power grid as a comprehensive power management product, which can quickly and effectively compensate the negative sequence current generated by the unbalanced load, and always ensure that the three-phase current flowing into the power grid is kept in a balanced state, greatly improving the power quality.

Model Description

Technical parameters

Technical parameters (continued)

SVGC Technical parameters

Most of the reactive power of the load is compensated by the LC capacitor bank, and the rest of the compensation is completed by the SVG module. The controller (ICMS) monitors the compensation of the SVG module and the LC capacitor bank.

HKK-SVGC composition = controller (ICMS) + LC + HKK-SVG module

Technical parameters

Product wiring diagram

Product wiring diagram

HKK-SVG Modular Compensation Unit

HKK-SVG module combined with LC capacitor bank realizes HKK-SVGC characteristics. The best choice for HKK-SVG is: 30kVar, 50kVar. 100kVar capacity modules.

■The picture on the right is the schematic diagram of HKK-SVG. The HKK-SVG is regarded as a controllable current source. Connecting the reactor can be equivalent to a linear impedance element. Controllable compensation current;

■Compared with traditional SVC, HKK-SVG has stable operation, long life, fast response, wide compensation range, smooth capacity adjustment, smaller harmonic components, and more stable system voltage;

■In the HKK-SVGC compensation method, the HKK-SVG module is used to improve the reactive power compensation performance (response time, stepless adjustment, etc.).

LC capacitor bank compensation unit
In HKK-sVGC compensation, LC is used as the main compensation; contactor type or smart capacitive type can be used.

Most of the loads in the power grid are inductive loads, and a certain proportion of capacitors are connected in parallel to compensate for the reactive power required by the inductive loads.

The traditional compensation method is cheap, and it is easy to produce switching oscillations, and the compensation effect is not good.

The use of HKK-SVGC overcomes the above weaknesses; ensures that the reactive power is stabilized within the required range, and improves the cost-effectiveness of the equipment.

ICMS Controller Unit
Controller (ICMS):

The controller monitors the running status of SVG and LC, so that SVGC runs according to the predetermined program

■7-inch touch color screen

■Real-time data monitoring functions such as: grid voltage, current, frequency, power factor, active power, reactive power, etc.;

■Have data recording functions such as: alarm information, operation records, SVG and LC operation switching status records, etc.;

■Have a variety of protection functions such as: overvoltage, undervoltage, phase loss, overload, over temperature, etc.

■Real-time control and monitoring of the running status of SVG and LC

■The remote communication function can provide 485 interface, Ethernet, USB interface, etc.;

■Three-phase common compensation, single-phase separate compensation, and mixed compensation can be selected flexibly

■The capacitor bank has an excellent first-out cycle mode;

■Have eighteen IO ports (expandable) thyristor switching/contactor switching optional;

■The target power factor can be set

Features

HKK-SVGc:

The traditional reactive power compensation method (LC) is combined with the HKK-SVG module to realize the improvement of reactive power compensation characteristics

Good compensation characteristics

Fast response time
Quick response 33.4us

Full response 14.7ms

In the HKK-sVGC scheme:

■Quick response is realized by HKK-SVG module. Response time <50us, full response time <15ms;

■HKK-SVG module body has the advantages of power electronic switching. In traditional SVC, the traditional thyristor switches more than 100ms once, while the IGBT switching speed in SVG is as high as 200,000 times per second.

Excellent compensation effect
Compensation effect timing diagram when LC and sVG are used together (LC-270kvar group, SVG-30kvar)

■100~200ms:

The reactive power of the load increases suddenly, and the LC is too late to act, and the SVG will respond in real time to compensate the reactive power of the system;

■200-500ms:

LC reaction input compensation, at this time SVG will reduce the compensation capacity in real time;

■900~1000ms:

When the reactive power of the load suddenly decreases, and the LC has no time to cut off the input capacitor, the SVG will issue a reverse-compensated reactive power in real time to compensate the overcompensated capacity of the LC;

■1000ms ~ :

The LC will cut off the excess compensation capacity, and the SVG will track the system reactive power change in real time and eliminate the remaining reactive power in the system.

IGBT full control era
■A large number of power electronic equipment and inductive loads are put into operation

■The low power factor in the power grid has endangered the safe operation of the equipment and has become a link that must be solved

■Electricity revenue, transmission line security

■Detrimental damage to new equipment caused by too low power factor

■Traditional LC compensation cannot meet the precise adjustment of reactive power compensation

■Reactive power compensation technology has entered the era of IGBT full control (SVG)

Flexibly selectable compensation ratio
For the HKK-SVG module and LC combination in the HKK-sVGC scheme, it can achieve:

■Performance adjustment of HKK-sVGC scheme: HKK-sVGC compensation range

■HKK-SVGC scheme can configure the capacity ratio of LC and HKK-SVG according to user requirements to realize price adjustment

Excellent value for money

SVG Development Trend of Low Voltage Reactive Power Compensation

HKK-SvGC Compensation compared with other compensation effects