FC filter capacitor

1. Product introduction

The loads in the steel, petrochemical, metallurgical, coal, printing and dyeing industries will generate a large number of harmonics during the working process, causing serious pollution to the power system and affecting the quality of power supply and consumption. The passive power filter device absorbs the harmonic current generated by the harmonic source nearby, which is an effective measure to suppress the harmonic pollution. It is mainly composed of a proper combination of filter capacitors, air-core filter reactors and non-inductive resistors, and is connected in parallel with the harmonic source during operation to play a filtering role and take into account the needs of reactive power compensation and voltage regulation. As it is simple in structure, reliable in operation, convenient in maintenance, both economical and practical, it has been widely used currently.

2. Product features

² Strong completeness: the whole device includes: a) distribution cabinet: with circuit breaker, disconnector and current transformer, etc. inside; b) relay protection panel: realizing the functions of protection, automatic switching, measurement and communication; c) primary element: including filter capacitor, filter reactor, discharge coil, lightning arrester and spray fuse, etc.; d) Steel frame and fence, etc.

² Miniaturization of the device: In order to facilitate transportation and reduce the floor space, the complete device has a compact structure and a reasonable layout, fully considering the simplicity and intuitiveness of installation and operation and maintenance.

² Good series performance: the main equipment, steel frame and spare parts of the complete device are universal, and different capacity levels are appropriately divided. Regarding the selection of circuit breakers and other control equipment, protection devices and automatic switching, as well as the protection of a single capacitor, the opinions and suggestions of the user are fully respected, and the contract requirements are strictly followed in the complete device manufacturing process.

² Strong flexibility: it can meet the different requirements of urban power grids, rural power grids and heavy industrial loads for power quality, and can compensate reactive power at the same time, which increases the system voltage, and improves voltage distortion rate.

² Strong adaptability: China has a vast territory, with great differences in climatic conditions in North and south, cold tropics and high altitude. The different designs of the complete device fully meet its reliable operation under different climatic conditions.

3. Application field

² High power rectifier devices: such as electrolytic aluminum, intermediate frequency furnace, rolling mill, etc. during the shutdown and opening of semiconductor devices, characteristic harmonics related to their wiring mode will be generated. The harmonic current flowing into the system will affect the normal operation of transformers and motors, resulting in overload or even burning.

² Electric locomotives: at present, most of the electrified railway locomotives in operation in various countries use AC 25-35kV power supplies, and are powered by two-phase traction substations, which will inevitably cause the three-phase load asymmetry, injecting harmonic currents and negative sequence currents into the power system. Generally, filters of the same capacity are installed on the two power supply arms of the traction transformer.

² Loads containing ferromagnetic devices: such as transformers, iron-core reactors, etc., when they are working in a saturated state, due to the nonlinearity of their magnetization curves, a certain number of harmonics will be generated, especially the triple frequency harmonics, when there is a parallel compensation capacitor in the system, an appropriate proportion of the capacitive reactance of the capacitor and the inductive reactance of the system will cause serious amplification of the  triple frequency harmonics.