SVC-Problem Solving

◆ Electric Arc Furnace

Electric Arc Furnace is regarded as a nonlinear and erratic load, it will create a series of adverse effects to the power grid, mainly including:

■ Serious three-phase unbalance of the power grid, negative sequence current.
■ High order harmonics, such as 24th even harmonics and 3rd, 5th, 7th odd harmonic, severe voltage distortion becomes more complicated.
■ Serious voltage flicker.
■ Low power factor

One of the methods to completely resolve above problems is to install a dynamic static reactive power compensation device (SVC) with quick response speed, the response time of SVC system of RXPE is less than lOms. The strict technical requirements is met, reactive current to electric arc furnace is provided, voltage level of bus is stabilized, the output of the metallurgical active power is increased, and minimize the impact of flicker. The isolated phase compensation function of SVC can eliminate the three-phase unbalance caused by electric arc furnace, filtering devices, the harmful high order harmonics and improved power quality and power factor are achieved through providing capacitive reactive power to the system.


◆ Rolling Mill

The reactive power impulse caused by rolling mill and other industrial symmetry loads during working will generate the following effects to the power grid:

■ Severe voltage level drop and voltage fluctuation make the electrical equipment inoperative, and reduce the production efficiency.
■ Reduction of the power factor
■ Harmful high order harmonics in transmission device of load, mainly including odd harmonics, such as 5th, 7th, 11th, 13th and side frequency, which will lead to serious distortion of voltage level.

RXPE’s SVC can perfectly solve the aboved problems. A stable bus voltage is maintained, the harmonics is eliminated, and the power factor is close to 1.


◆ Power supply of electric locomotive


When the transportation way of electric locomotive protects the environment, however, it also seriously“polluted”the power grid. As the electric locomotive has single phase power supply, such single-phase load causes a serious three-phase unbalance in the power grid, a low power factor, and negative sequence current.

At present, one of the ways to solve this problem is to install SVC at appropriate locations along the railway. The three-phase balance of the power grid is got through the quick isolated phase compensation function of SVC, and the improved power factor is achieved through filters. RXPE’ SVC has solved the problems perfectly not only technically but also economically with its excellent cost performance.


◆ Hoist

Hoist and other heavy loads will have the following effects on power grids at work:

■ Voltage level drop and voltage fluctuation in the power grid.
■ Low power factor
■ Harmful high order harmonics in transmission device

RXPE’s SVC can perfectly solve the problems.


◆ Long-distance power transmission

Global power currently trends to greater than power grid, long-distance transmission, high energy consumption. At the same time, it also demands the transmission and distribution system to be more effective. SVC can significantly improve the transmission and distribution performance of power system, which has been widely proved in the world. In order to maintain a balanced voltage as the power system in different conditions, the installation of SVC at one or more suitable locations of the power grid is necessary. The following purposes are achieved:

■ Stabilization of the voltage of weak system
■ Reduction of the transmission losses
■ Increment of transmission capacity makes the existing power grid play its maximum efficiency
■ Increment of transient stability limit
■ Increment of damping under small interference
■ Enhancement of voltage control and stability
■ Elimination of power flunctuation


◆ Secondary substation in city (66/110 kV)

In regional power grid, we generally use the TSC to compensate the reactive power and improve power factor. However, this can only provide capacitive reactive power to the system, but not achieve rapidly and precisely regulation with the changes of load which is easy to cause inverted injection of reactive power to the system, the fluctuation of the bus voltage, the damage of the electrical equipment and instability of the system.

RXPE’s SVC system can quickly and accurately make capacitive and inductive reactive power compensation. When SVC stabilize bus voltage and improve the power factor, the inverted injection of reactive power is solved thoroughly. In addition, the SVC may take full advantage of original existing fixed capacitors bank, achieving the best effeciency with the least investment. It becomes the most effective way to improve the quality of power supply of regional power grid.


Typical Projects