slide 1: What is Reactive Power Compensation and How Capacitor
Power Bank Works
1 What is reactive compensation
Reactive compensation improves grid power factor in power supply system. It also reduces the power loss
of transformer and transmission line. It improves power efficiency and the environment.So the reactive power
compensation device plays an important role in the power supply system. Improper selection or use of
compensation device will cause many factors such as harmonic increase and voltage swell or dip.
2 Advantages of reactive power compensation
Most power equipment is inductive loading it takes much reactive power from power system because its
power factor lower than 1 when working. So we need to improve the power factor by reactive power
compensation it has following advantages:
1 Stabilize the voltage of power grid and improve power quality
2 Improve power factor reduce capacity and equipment investment
slide 2: 3 Reduce line loss improve the transmission capacity of active power
4 Balance the active power and reactive power of three-phase power grid
5 Reduce the loss of transformer improve the utilization of transformer.
1.1 Schematic analysis
Reactive power Q1↓ Apparent S1↓ Total current I1↓ active power P not change
Power factor COSΦ↑P (not change )/S↓
Since reactive power Q1↓ with apparent S1Q1↓ total current I1Q1↓ active power is unchanged
Power factor COSΦ↑P unchanged/ S↓
1.2 Economical Advantage
One factory transformer is 2000kVA power factor is 0.85 at present loading rate is 80 target improved
power factor is 0.95 how much economic benefits will it take
Bill calculation
Power factor 0.85Bill forfeit2.5
Power factor 0.95or 1Bill reward0.75
Average unit price 1usd/degree
Annual forfeit before compensation2000x0.85x0.8x24x30x12x1x2.5293000 usd
Annual reward after compensation2000x0.95x0.8x24x30x12x1x0.7599000 usd
Total billing: 293000+99000392000usd
Super Capacitor Power Bank
slide 3: 1What is intelligent capacitor
。
Intelligent capacitor power bank set the self-healing low-voltage capacitor bank as the main body by an
intelligent measurement processer as control center utilized the micro electronic software and hardware
technology for thyristor zero crossing control. The contact delay switching of the mechanical magnetic holding
relay and the zero crossing switching technology of the mechanical magnetic holding relay and the silicon
controlled thyristor composite switch circuit to the low-voltage power capacitor Power factor compensation shall
be carried out for 0.4kV low-voltage line.
The intelligent capacitor integrates sensor technology network technology and the latest electrical
technology and combines them into intelligent miniaturized and networked ones. Compared with the traditional
low-voltage reactive compensation products the operation is simpler the interface is more intuitive there is no
professional requirements for users and it has automatic cycle switching 3 phase common compensation
dispersion compensation hybrid compensation hierarchical optimization compensation hybrid hierarchical
optimization compensation overcurrent / overvoltage / undervoltage / undercurrent voltage loss phase loss
harmonic temperature and other protection measurement control communication and other functions.
The structure of the intelligent capacitor breaks through the existing low-voltage reactive power
compensation equipment and realizes the new mode of decentralized control and centralized management. The
compensation system has the characteristics of fewer devices small temperature rise small volume small
slide 4: power consumption anti harmonic the structure is simple easy to realize standardization flexible capacity
configuration safety reliability economy and convenient use. It also predicts the input capacitor improves the
active power of distribution transformer reduces the investment of capacity increase and reduces the loss of
compensation system. The real-time switching of the decentralized control increases the stability of the
compensation system the zero crossing control reduces the impact of inrush current on the system voltage
stabilizes the system power grid reduces the equipment loss and improves the service life of the capacitor and
is of great significance for energy conservation and environmental protection.
2 Economical Advantage
1. Whether there is anti harmonic need to be divided into: conventional intelligent capacitor and anti harmonic
intelligent capacitor
2. Different compensation methods can be divided into: three-phase common compensation intelligent capacitor
and split phase compensation intelligent capacitor
3. The different filling medium of capacitor body can be divided into dry type intelligent capacitor and oil type
intelligent capacitor
4. Different compensation locations can be divided into: centralized compensation intelligent capacitor and local
compensation intelligent capacitor
Different types of intelligent capacitors can meet the needs of different groups of people giving customers a
great choice of space which can be applied to various fields. There are many types of intelligent capacitors.
Now they have been applied to rail transit petroleum chemical industry electric power metallurgy paper
making buildings buildings residential buildings shopping malls catering and other industrial users which can
save energy and reduce cost Low power consumption and energy saving.
3 、 Difference from ordinary capacitors
First the intelligent capacitor uses the most advanced switching switch to realize zero crossing switching
without inrush current.
Second the intelligent capacitor can realize over-voltage and under voltage protection the capacitor over
temperature and phase loss protection. When the internal temperature of the capacitor exceeds 60 degrees the
capacitor will cut itself off improve its service life and ensure the safe operation of the system. At the same time
the intelligent capacitor can effectively self diagnose the operation parameters of the main body. Once the self
inspection fault occurs the whole machine responds quickly and exits the operation.
Source -
https://medium.com/sfereelect/what-is-reactive-power-compensation-and-how-capacitor-power-bank-
works-b306cd7a3989