Harmonic control and reactive power compensation devices for mill

Under load, DC mill, rectifier and frequency inverter etc. will produce a large quantity of harmonic current, which may, if not controlled, seriously affect the safe operation of power grid and sensitive loads in the grid. Moreover, power factor of DC mill etc. for speed regulation load is very low. Traditional reactive power compensation device (capacitor cabinet) cannot be put into normal operation since it cannot resist and eliminate the harmonic interference, thus leading to serious waste of electric energy. Even if capacitor cabinet can be put into service, it may possibly give rise to fuse burnout, capacitor blasting and such circumstances, which are very dangerous. 

Our harmonic control device can solve the foregoing issues in an efficient manner. Our devices can not only be used for harmonic control, but also reactive power compensation. Therefore, harmonic pollution can be solved completely and power factor can be improved, with significant economic benefits. Generally, investment cost can be recovered in 3 - 5 months approximately.

Ilter reactive power compensation device for mill:

It is suitable for circumstances when reactive power compensation cabinet cannot be put into normal service or capacitor, fuse or such components are damaged after operation of the aforesaid cabinet due to excessive harmonics in 0.4 - 1KV system. This device uses series reactors with fixed reactance ratio (i.e. 5.5%, 6% and 13%) in capacitor branch to protect capacitors against damage, so as to make reactive cabinet be put into normal service. This device adopts the modular structure and intelligent control, which can not only be used for harmonic control but also reactive power compensation. It is primarily used for reactive power compensation for fundamental wave, secondly harmonic control. After compensation, power factor is ≥0.96 and it can be used for harmonic suppression, with remarkable effects of energy saving. Generally, cost can be recovered in 3 - 5 months approximately.

Dynamic filter compensation device for mill:

This device is suitable for rolling mill, electric arc furnace, high power electrolysis, DC speed regulation device for thyristor and rectifier etc., with quick response. It can realize comprehensive real-time harmonic compensation, reactive power, three-phase imbalance and voltage fluctuation control etc. It can be used for compensating reactive power of the system, increasing power factor, regulating network voltage, decreasing line loss, improving power supply, increasing use ratio of power supply and distribution equipment, stabilizing fluctuation of network voltage, so as to make voltage fluctuation reach the national standard.

Main features:

1. This device is designed and manufactured specially for the user systems, to eliminate characteristic harmonics, i.e. 5th, 7th, 11th and 13th orders etc., with remarkable effects of filtering.

2. It can not only be used for harmonic control but also reactive power compensation. 

3. After putting filter into service, efficiency of power utilization can be obviously improved. It can relieve current shock arising from impact load, decrease voltage fluctuation, suppress voltage flicker, increase voltage stability and improve voltage quality. Power factor can be increased above 0.96. Line loss of the user can be decreased and loading efficiency of distribution transformer can be improved, with remarkable economic benefits. 

4. High-performance vacuum switches are used for switching of various filter branches, with perfect control system and complete protection functions. It is available for short-circuit protection, over-voltage protection, over-current protection etc., with reliable and simple operation. Benefits of harmonic control: 

Benefits of harmonic control: 

1. After acceptance of harmonic control device by competent department of the Power Supply Administration, corresponding quality deposits for power supply/ utilization can be recovered from the competent department, so as to expand cash flow of the Company.

2. After installation of harmonic control device, harmonic current can be efficiently decreased, effective capacity of transformer can be increased, corresponding load-carrying capacity can be increased and investment necessary for capacity expansion can be decreased. 

3. After installation of harmonic control device, transformer loss can be efficiently decreased and coefficient of transformer safety operation can be improved, so as to realize energy saving and cost reducing.