According to the capacitor installation location, the submerged arc furnace is generally divided into three modes: high-pressure reactive power compensation implemented on the high-pressure side and medium-pressure side of the furnace and direct compensation on the low-pressure side and short-line side of the furnace. The high- and medium-voltage reactive power compensation has obvious effects on improving the power supply condition of the high-voltage side and increasing the operating power factor, but it is effective for reducing the reactive power loss of the short-circuit network on the low-voltage side, increasing the output of the transformer, and improving the three-phase short-circuit layout. Three-phase imbalance is powerless. In the case of submerged arc furnaces, the generation of reactive power is mainly caused by the arc current. If compensation is performed on the low voltage side, a large amount of reactive current will flow through the loop formed by the low-voltage side capacitor and the arc without compensation. Short network, transformer and power supply network before the point. While improving the power factor, the active power output of the transformer can be increased, and the reactive power consumption of the transformer and the short net can be reduced. At this time, the reactive power consumption of the short net is compensated locally, and the reactive current does not flow through the transformer and so on. At the same time, the power factor reduces the loss of transformers and short networks, and also increases the active power output of the transformer. The power input from the transformer to the furnace will increase. At the same time, due to the correct compensation mode, the three-phase short-circuit layout can be improved. The three-phase unbalanced condition makes the power center, thermal center and hearth center of the electric furnace overlap, the electric furnace crucible increases, and the heat distribution is reasonable, thereby improving the reaction conditions, increasing the output, quality, and reducing the unit power consumption and raw material consumption. In addition, short-circuit compensation should consider harmonic factors at the same time to absorb harmonics, reduce the harmonic content of users' electrical systems such as transformers, and extend the service life of equipment accordingly.
(1) Large installation capacity
(2) Low voltage
(3) Large current
(4) Large harmonic current during operation
(5) Bad environment (high temperature, dust, etc.)
(6) Inrush current during switching is not suitable for frequent switching
(7) Phase compensation is used to improve the unbalanced status of three phases
Reactive power compensation for high reactive power equipment such as submerged arc furnace and calcium carbide furnace.