A Discussion on the Application of New Types of Reactive Power Compensation Devices in the Metallurgical Industry

The utilization of thyristor switches for capacitor switching primarily leverages the rapid zero-crossing switching characteristic to prevent inrush current, thereby reducing the risk of capacitor overload and damage. Moreover, thyristor switches are well-suited for fluctuating load conditions, ensuring normal compensation and harmonic mitigation.

The thyristor capacitor filter compensation device not only performs reactive power compensation but also effectively filters specific harmonics in the grid. It is user-friendly and cost-effective. However, it lacks continuous dynamic compensation in power systems and cannot dynamically track changes in reactive power demand based on real-time load conditions. Given the complex and variable power grid environment in metallurgical industry settings, as well as frequent equipment start-ups and shutdowns, this device may be influenced by the grid environment and could potentially amplify harmonics or generate resonance.

1. Active Power Filter (APF) Compensation Device

The active power filter compensation device, also known as APF, can only be utilized in low-voltage power grids with limited compensation capacity due to imperfect development and research technology. In high-voltage power grids, it cannot serve as a primary method for harmonic suppression. The system voltage value at this steel enterprise is 35KV falls within the high-voltage compensation range.

2. Adoption of Static Var Generator (SVG)

SVG represents a novel type of compensator that integrates harmonic suppression with reactive power compensation functions using third-generation static reactive power technology based on voltage source inverters. Its principle involves converting reactive power through high-frequency switching of power electronic devices which has replaced traditional methods involving large-capacity capacitors and inductors while significantly reducing energy loss and equipment volume—thus enhancing overall performance levels for reactive power compensators.
 
SVG excels at achieving rapid dynamic compensation for both reactive powers as well as harmonics while also addressing unbalanced loads and zero-sequence harmonic currents; however its price point remains relatively high.