CN203261040U - Low-voltage dynamic reactive power compensation device - Google Patents

Abstract

The utility model relates to a low-voltage dynamic reactive power compensation device, which includes a power circuit breaker (1), several groups of low-voltage three-phase capacitors (2) and current transformers (3), and also includes a dynamic compensation controller (4) , several three-phase intelligent non-contact switches (5) and several branch circuit breakers (6), the working power input terminals of each three-phase intelligent non-contact switches (5) are respectively connected with the working power of the dynamic compensation controller (4) The output terminals of the power supply are connected, and the input terminals of the control signals are respectively connected with the output terminals of the control signals of the dynamic compensation controller (4). It has the advantages of fast response speed, intelligent reactive power compensation that can follow the changes of the power grid, zero-voltage switching when switching capacitors, is not easy to generate overvoltage, low noise when switching, and long service life. It can selectively switch capacitors with appropriate capacity according to the change of grid load, so that multiple performance indicators of the grid can always be kept at the best level, the compensation effect can always be in the best state, and the use effect is better.

Description

Low-voltage dynamic reactive power compensation device

technical field

The utility model relates to electric equipment, in particular to a high-voltage reactive compensation device.

Background technique

The use of low-voltage reactive power automatic compensation device can reduce the power loss of power supply and distribution equipment, improve the utilization rate of power supply and distribution equipment, and improve the voltage quality of power supply and distribution power to a certain extent. Therefore, it has always been highly valued by power supply companies and power customers. valued and widely used. The low-voltage reactive power automatic compensation device has a history of decades. Due to the continuous development of electric power, electrical appliances and electronic technology, the performance of the device has been continuously improved, especially the application of modern power electronics and microelectronics technology in the low-voltage reactive power automatic compensation device. The switching performance of switching low-voltage power capacitors has been greatly improved, and more functions in measurement and statistics can be realized.

However, the current structure of low-voltage reactive power automatic compensation devices commonly used in society is to switch low-voltage power capacitor banks with AC contactors, which has the following shortcomings: first, the response speed is slow, and intelligent reactive power compensation cannot be performed quickly following changes in the power grid; second, capacitors The switching time cannot realize the voltage zero-crossing switching, and it is easy to generate overvoltage, which will cause early damage to the equipment; third, the noise is large during switching, and the service life is short.

Contents of the invention

The utility model aims at the above-mentioned defects of the existing low-voltage reactive power automatic compensation device, and provides a fast reflection speed, which can quickly perform intelligent reactive power compensation following changes in the power grid, and can realize voltage zero-crossing switching when switching capacitors, and is not easy to generate overvoltage , Low-voltage dynamic reactive power compensation device with low noise and long service life during switching.

The technical solution of the utility model is: it includes a power circuit breaker, several groups of low-voltage three-phase capacitors and current transformers, and it also includes a dynamic compensation controller, several three-phase intelligent non-contact Point switch and several branch circuit breakers, the primary side of the current transformer is installed on a phase line of the low-voltage bus, and the two ends of the secondary side of the current transformer are respectively connected with the two current signal input terminals of the dynamic compensation controller, and the dynamic compensation control The two phase voltage signal input terminals of the circuit breaker are respectively connected to the other two phase lines other than the current transformer installed on the low-voltage busbar, the power supply terminal of the power circuit breaker is connected to each phase line of the low-voltage busbar, and the load terminal is connected to the power supply terminals are connected to the three-phase power input terminals of the dynamic compensation controller respectively, the power input neutral terminal of the dynamic compensation controller is connected to the low-voltage bus neutral line, and the load terminals of each branch circuit breaker are respectively connected to the three-phase intelligent non-contact terminals of the same group. The power supply terminals of the switches are connected, the load terminals of each three-phase intelligent non-contact switch are respectively connected with the same group of low-voltage three-phase capacitors, and the working power input terminals of each three-phase intelligent non-contact switch are respectively connected with the working power supply of the dynamic compensation controller. The output terminals are connected, and the control signal input terminals are respectively connected with the control signal output terminals of the dynamic compensation controller.

The technical effects of the utility model are: it has fast response speed, can quickly perform intelligent reactive power compensation following changes in the power grid, can realize voltage zero-crossing switching when switching capacitors, is not easy to generate overvoltage, has low noise when switching, and has a long service life. long advantage. It can selectively switch capacitors with appropriate capacity according to the change of grid load, so that multiple performance indicators of the grid can always be kept at the best level, the compensation effect can always be in the best state, and the use effect is better.

It is suitable for power frequency power systems below 1000V to improve power factor, improve power supply quality and reduce line loss. It automatically tracks the change of the power factor of the network, and automatically switches the voltage of each capacitor at zero crossing, so as to realize real-time dynamic automatic compensation of reactive power according to the change of the grid load.

The device can be directly connected in parallel with inductive loads such as electric motors, and can be installed locally and used outdoors. It is especially suitable for oil field systems. It can effectively improve the power factor, reduce line loss, and increase the output capacity of the transformer. The compensation device can dynamically track the changes of reactive power or reactive current in the network to automatically switch capacitors at zero crossing in groups, and has the characteristics of fast switching response, no inrush current, no overvoltage, etc., and can display voltage, current, power factor, etc. Parameters, at the same time, it has various comprehensive protection functions such as over-current, over-voltage, under-voltage, phase loss, over-harmonic, over-compensation, system failure, phase loss, overload, etc., and self-discharge protection functions, and has a parameter memory function, the system The parameters will not be lost after a power failure, and it will automatically enter the running state after the power grid is restored.

The design of the compensation device adopts an advanced dynamic compensation controller for operation control, and uses an intelligent non-contact switch to switch capacitors, which can automatically switch capacitor banks according to the real-time sampled voltage, current, and power factor, and To ensure that the capacitor can be switched on when the voltage crosses zero and cut off when the current crosses zero, without overvoltage, it is especially suitable for fast tracking compensation of frequent operations and frequent load changes.

The utility model has the following characteristics:

1. When switching capacitors, it is guaranteed that the voltage is zero-crossing to close, and the current is zero-crossing to open the switch. When the switch is turned on and off, the inrush current and overvoltage are low, and the contacts are not sintered.

2. There is no pressure drop during operation, no energy consumption, and no harmonic generation.

3. It has multiple protection functions and high operational reliability.

4. The response speed is fast, and the dynamic changes of the power grid can be tracked at any time to realize fast dynamic automatic reactive power compensation.

The low-voltage dynamic reactive power compensation device serves for power saving, and this product itself is a good product for saving resources. At present, it is widely used in many areas in China and has achieved good results. It is believed that with the passage of time, this change will greatly promote the development of low-voltage reactive power automatic compensation technology and produce good social and economic benefits.

Description of drawings

Fig. 1 is the schematic circuit diagram of the utility model embodiment. 

Detailed ways

As shown in Figure 1, it includes a power circuit breaker 1, several groups of low-voltage three-phase capacitors 2 and current transformers 3, and it also includes a dynamic compensation controller 4, several three-phase intelligent The non-contact switch 5 and several branch circuit breakers 6, the primary side of the current transformer 3 is installed on a phase line of the low-voltage bus 7, and the two ends of the secondary side of the current transformer 3 are connected with the two currents of the dynamic compensation controller 4 respectively. The signal input terminals are connected, and the two phase voltage signal input terminals of the dynamic compensation controller 4 are respectively connected with the other two phase lines other than the current transformer 3 installed on the low-voltage bus 7, and the power terminals of the power circuit breaker 1 are connected with the low-voltage bus 7 respectively. The phase line is connected, the load end is connected with the power end of each branch circuit breaker 6 and the three-phase power input end of the dynamic compensation controller 4, and the power input neutral line end of the dynamic compensation controller 4 is connected with the low-voltage bus 7 neutral line. The load terminals of the branch circuit breakers 6 are respectively connected to the power terminals of the three-phase intelligent non-contact switches 5 of the same group, and the load terminals of each three-phase intelligent non-contact switches 5 are respectively connected to the low-voltage three-phase capacitors 2 of the same group. The working power input terminals of the three-phase intelligent non-contact switch 5 are respectively connected with the working power output terminals of the dynamic compensation controller 4 , and the control signal input terminals are respectively connected with the control signal output terminals of the dynamic compensation controller 4 .

It also includes a compensation device housing 8 and three lightning arresters 9, each lightning arrester 9 is installed in the compensation device housing 1 and connected between each phase of the load end of the power circuit breaker 1 and the ground terminal of the compensation device housing 8, and the power supply is disconnected. Device 1, each group of low-voltage three-phase capacitors 2, each three-phase intelligent non-contact switch 5 and each branch circuit breaker 6 are respectively installed in the compensation device housing 1, and the dynamic compensation controller 4 is installed on the panel of the compensation device housing 8 . A capacitor working indicator light 10 is respectively connected between one phase of the load end of each three-phase intelligent non-contact switch 5 and the neutral line of the low-voltage bus 7 . Each capacitor working indicator light 10 is respectively installed on the panel of the compensation device housing 8 . Fuses 11 are respectively provided between the load end of the power circuit breaker 1 and the three-phase power input end of the dynamic compensation controller 4 . Each fuse 11 is respectively mounted on the panel of the compensation device housing 8 .

Claims (4)

1. low-voltage dynamic reactive power compensation arrangement, it comprises power circuit breaker (1), some groups of low voltage three-phase capacitors (2) summation current transformers (3), it is characterized in that: it also comprises dynamic compensation controller (4), several three-phase intelligent noncontacting switches (5) and several branch circuit breaker (6) identical with low voltage three-phase capacitor (2) group number, current transformer (3) primary side is installed on (7) phase lines of low-voltage bus bar, the two ends of current transformer (3) secondary side link to each other with two current signal inputs of dynamic compensation controller (4) respectively, two phase voltage signal inputs of dynamic compensation controller (4) are installed current transformer (3) in addition two phase lines in addition with low-voltage bus bar (7) respectively and are linked to each other, the power end of power circuit breaker (1) links to each other with each phase line of low-voltage bus bar (7) respectively, load side links to each other respectively with the power end of each branch circuit breaker (6) and the three-phase power input end of dynamic compensation controller (4), the power supply input zero line side of dynamic compensation controller (4) links to each other with low-voltage bus bar (7) zero line, the load side of each branch circuit breaker (6) links to each other with the power end of on the same group three-phase intelligent noncontacting switch (5) respectively, the load side of each three-phase intelligent noncontacting switch (5) links to each other with on the same group low voltage three-phase capacitor (2) respectively, and the working power input of each three-phase intelligent noncontacting switch (5) links to each other with the working power output of dynamic compensation controller (4) respectively, the control signal input links to each other with each control letter output of dynamic compensation controller (4) respectively.

2. low-voltage dynamic reactive power compensation arrangement as claimed in claim 1, it is characterized in that described it also comprise compensation arrangement housing (8) and three lightning arresters (9), each lightning arrester (9) is installed in the compensation arrangement housing (1) and is connected between power circuit breaker (1) load side each and compensation arrangement housing (8) earth terminal, power circuit breaker (1), each organizes low voltage three-phase capacitor (2), each three-phase intelligent noncontacting switch (5) and each branch circuit breaker (6) are installed in respectively in the compensation arrangement housing (1), and dynamic compensation controller (4) is installed on compensation arrangement housing (8) panel.

3. low-voltage dynamic reactive power compensation arrangement as claimed in claim 2, it is characterized in that being connected with respectively capacitor relay indicating light (10) between one and low-voltage bus bar (7) zero line of described each three-phase intelligent noncontacting switch (5) load side, each capacitor relay indicating light (10) is installed in respectively on compensation arrangement housing (8) panel.

4. low-voltage dynamic reactive power compensation arrangement as claimed in claim 2, it is characterized in that being respectively equipped with fuse (11) between the three-phase power input end of the load side of described power circuit breaker (1) and dynamic compensation controller (4), each fuse (11) is installed in respectively on compensation arrangement housing (8) panel.

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