Reactive Power Compensation/Automatic Reactive Voltage Regulator

+++++GeneralWith the rapid development of national economy and the improvement of people's living standard, people's demand for electricity is increasing day by day. It puts forward higher request to the reliability and quality of power supply. However. Distribution network construction is seriously lagging behind, the grid is weak, facilities aging, line length, small diameter, most of the power distribution transformers are high energy consumption, network loss is increasingly prominent.
Voltage quality is one of the important indicators to measure the power quality of power system, and its quality depends on whether the power flow distribution is reasonable or not. Due to the increasing load and the power supply, the network structure of the power system not only changes the network structure of the power system, but also changes the power distribution of the system. May even cause serious problems in local areas, the situation is generally low voltage level. This is not only related to the power system to provide users with power quality issues, but also directly affect the safety and economic operation of the power grid. At the same time, it is necessary to consider the power factor and voltage of the network, because the network power factor and voltage reduction will make the electrical equipment is not fully utilized, thereby reducing the transmission capacity of the network, and cause loss increase.Reactive power compensation benefits
lImproves system power factor
lReduces network losses
lAvoid penalty charges from utilities for excessive consumption of reactive power
lReduces cost and generates higher revenue for the customer
lIncreases system capacity and saves cost on new installations
lImproves voltage regulation in the network
lIncreases power availability+++++Product scopeRated voltage:6kV to 35kV
(30kV-230kV Power transformer substation)
Rated frequency:50Hz, 60Hz
Rated reactive power capacity:50kvar-36000kvar
Environment temperature:-45ºC-+55ºC
Altitude:<4500m
Compensation taps:9 to 25 taps
Voltage regulation range:50%Un-100%Un
Regulation reactive power range:25%Qn-100%Qn
Impedance:<2.0%
Controller system:DWK controller
+++++ Working principleThe work principle of Farady regulating type capacitors is that: Connect all the capacitors to the electric network with voltage regulator ,the output reactive power will be adjust by voltage regulator, refer to the capacitor output power formula: Qc=(U/Un)²Qn.
The set of equipment is made up by following equipments:
1. Load break switch
2. Insolating switch
3. Voltage regulator
4. Intelligent controller
5. Capacitors
6. Lighting arrester
7. Metering CT, PT
Assuming that the nominal capacitance of the capacitor is Qn , the connected voltage regulator regulation range is 50%Un-100%Un, so refer to the formulaQc=(U/Un)²Qn
,voltage regulator is designed with 9 taps tap changer to change the network voltage, see figure 2 , the output reactive power in every regulator position
+++++ AdvantagesThe traditional way of reactive power compensation is changing the quantity of capacitors to adjust output reactive power, change method is usually switch or contactor, will result in following hazards
1. The conventional reactive power compensation method has a large compensation capacity and the adjustment is not flexible, it will lead to the compensation is not suitable , often appear over and not enough.
2.The capacitor switching can cause over-voltage and inrush current, and it will seriously affect and reduce the service life of the switch.
3.When the capacitor is switched on, as the capacitor will charged and discharged, when it need to switch on again, which affects the speed of the switching..
According to the above problems, o company developed the FLYK type reactive power compensation device, has the following advantages:1.Energy conservation:Farady voltage regulating type capacitors will change the output reactive power by regulating voltage on capacitors, so that the reactive power can be adjusted smoothly. Comparing with other method, it can ensure the capacitors in best condition, the energy saving effect is much better
2.Low cost:If the old power transformer substation need to reform, only need to add a voltage regulator between the circuit breaker and capacitors, the original circuit breakers, reactors, capacitors can be reuse, greatly reduce the cost of transformation
3.Maintance Free:When traditional circuit breaker and contactor switching, switching devices and capacitors often damaged because of the above problems, result in high maintenance costs, using Farady devices, automatic control reactive power output, there is no potential risks of other equipments,greatly reducing maintenance and staff costs in power transformer substation