FGI Static Var Generator(SVG) in paper mill harmonic control typical case

1.introduction

In the power system, the power quality problem becomes more and more serious due to the input of a large number of nonlinear loads. Such as electric arc furnace, intermediate frequency furnace, mineral furnace, frequency converter, rectifier and other nonlinear load use, resulting in power quality problems such as flicker, harmonic, imbalance, overvoltage, undervoltage and so on. To a large extent, these problems have been unable to meet people's requirements for "high", "fine" and "sharp", and have also led to the loss of transmission and distribution devices in the power system.

Among them, the harm of harmonics is particularly prominent, which reduces the efficiency of the production, transmission and utilization of electric energy, causes overheating of electrical equipment, causes vibration, generates noise, and also leads to the aging of the insulation of the equipment, thereby shortening the service life of the equipment, and serious failures or even burns, so the control of harmonics is increasingly demanding.

Static Var generation (SVG) is the most advanced reactive power compensation method at present. Instead of using large-capacity capacitors and inductors to generate the required reactive power, on the contrary, through the high-frequency switching characteristics of the fully controlled power electronic device IGBT, to achieve a qualitative leap in compensation control technology, especially by improving the control algorithm, can achieve comprehensive compensation for harmonics and reactive power.

2.FGI scheme

The 35 kV power grid of a paper mill uses two main transformers, powered by 10 kV bus, and the main becomes one use and one standby. The 10 kV bus is equipped with nearly 60 branches and is equipped with 2 independent generators. In these devices, chlorine dioxide rectifiers, chlor-alkali rectifiers, low-voltage frequency converters, etc., are mainly 5th and 7th harmonics, and 5th harmonics exceed 5 times, which are ordered by the power company to rectify within a time limit.

Aiming at the problem of 5-phase harmonics in power grid governance, the project plans to install 10 kV 5MW SVG on the 10 kV bus bar. Through real-time monitoring of grid voltage, grid current, load current and other parameters, the reactive power of the grid can be rapidly and continuously adjusted to ensure the stable, efficient and high-quality operation of the grid.

After the device is put into use, the 5th harmonics of each power supply are greatly reduced, and the compensation effect is shown in the following table.

Compensating for pre-voltage harmonics

Compensated after voltage harmonics

3.Product advantage

The FGI Static Var Generator(SVG) device has excellent functional performance and can effectively manage various power quality problems in industrial sites. Compared with traditional compensation methods, it has the following advantages:

Static Var Generator(SVG) can suppress harmonics in the system and deal with the problem of three-phase unbalance.

Static Var Generator(SVG) can be connected to the on-site control system to achieve remote digital control.

Static Var Generator(SVG) can improve the power factor of the site and avoid force adjustment.

Static Var Generator(SVG) models are diverse, there are indoor, outdoor, air cooled, water cooled a variety of models, can be configured according to the site situation the best solution.

The full range of FGISVG solutions

Static Var Generator(SVG) as the most advanced reactive power compensation equipment, thanks to its excellent performance, more and more customers recognize and use Static Var Generator(SVG) to improve power quality and ensure the safety and stability of production work. As a leading brand in the Static Var Generator(SVG) field, FGI continues to carry out technological innovation to provide more professional power quality solutions for users in various industries.