CN2468202Y

CN2468202Y - Low-voltage comprehensive reactive-load compensation equipment

Info

Publication number: CN2468202Y
Application number: CN 00257698
Authority: CN
Inventors: 刘�东; 李振洋; 王涛; 杨军; 陈智育; 姜海涛
Original assignee: YANTAI DONGFANG ELECTRONIC INFORMATION INDUSTRY Co Ltd
Current assignee: YANTAI DONGFANG ELECTRONIC INFORMATION INDUSTRY Co Ltd
Priority date: 2000-11-08
Filing date: 2000-11-08
Publication date: 2001-12-26
Anticipated expiration: 2010-11-08

Abstract

The utility model relates to a low-voltage and comprehensive reactive compensation device, which is composed of a controller (1), a wave-carrying meter-reading concentrator (3), a wireless maintenance interface (4), a universal serial interface (5), a capacitor module (7), an air switch (11) and a current transformator (12). The low-voltage and comprehensive reactive compensation device can detect the parameters of a transformer, such as the voltage, the current, the active power, the reactive power, the power factor, etc., the measurement parameter can be transferred by a communication channel, and the reactive compensation can be realized by adopting the low-voltage and comprehensive reactive compensation device. The compensation capacity can be changed dynamically by following the change situation of the load, and the low-voltage and comprehensive reactive compensation device has good functions of improving the voltage quality and reducing the line loss and can be used for a power distribution system.

Description

The low-voltage comprehensive reactive power compensator

The utility model relates to a kind of power electronic equipment that distribution system is carried out reactive power compensation that is applied to.Reactive power is the part energy that flows back and forth between electric power system power supply and load, it does not do work to load, but its mobile meeting causes the energy loss on the circuit, and increased the voltage landing of circuit, therefore carrying out reactive power compensation has good economic benefits, can reduce power loss effectively and improve quality of voltage.

The method of carrying out reactive power compensation at present has multiple, and capacitor compensation is that price is the most cheap and use the simplest a kind of in these modes.Capacitor compensation can be divided into two kinds of fixed compensation and dynamic compensations, and fixed compensation is exactly in the capacitor fixed access system with a constant volume, and dynamic compensation method requires to regulate at any time according to system conditions the condenser capacity of input.The control method of dynamic compensation has three types, and first kind is to regulate manually, and second kind is that contactor or air switch are regulated automatically, and the third is to adopt controllable silicon or solid-state relay to regulate automatically.Wherein the third is that performance is best, has obtained at present using widely.The controller of this series products has a variety of, the circuit of various ways such as used from the discrete component to the single-chip microcomputer on the circuit, but the function ratio aspect power back-off is similar, and the function of whole device is also more single, fully as one independently reactive-load compensation equipment make and use.

At Chinese patent CN88202441, it discloses an implementation that carries out reactive power compensation, and its control circuit part is made of discrete component, its advantage is that circuit is simple, and cost is lower, realizes easily, but weak point is a function singleness, can not realize senior calculation function.

At Chinese patent CN98223360, it discloses a kind of novel reactive power compensator, its advantage is that controller is made of single-chip microcomputer, and has the intelligent operation/cutting algorithm, but its weak point is its allomeric function and still has only reactive power compensation not have transformer state measurement or other additional function.Analyze existing reactive power compensator, their parts that all comes with some shortcomings to some extent can be analyzed as follows:

1. the power loss of solid-state relay is big, and the disconnected pressure drop of every solid-state relay reaches about 2 volts, if the operating current of the every phase of a group capacitor is 100A, then the power consumption of three-phase is 600W, and energy loss and heating are all very serious;

2. device self-protection function is poor, has only by fuse when break down in device inside and protects.

3. do not consider the transformer measuring ability, if desired the operating state of transformer is just detected the transformer checkout gear can only be installed in addition again, increase expense expenditure, and make electrical wiring complicated.

4. do not have remote control and remote signalling function, do not have the communication interface function yet, make reactive power compensator be not suitable for communication, can't realize overall monitor distribution transformer with electrical power distribution automatization system.

Inventors of the present utility model are through with keen determination research, in the control of reactive power compensator, adopted novel controller, not only expanded the function of existing controller, make it can control the reactive compensation capacity of input, and can the electric parameters of step down side be detected, and have remote signalling, distant control function and telecontrol communication function, so far finished the utility model.

The purpose of this utility model is: make reactive power compensator have no-power compensation function, can carry out transformer and detect, and have the function of carrying out communication with distant place control centre and accepting remote control.

Second purpose of the present utility model is: make reactive power compensator have perfect self-protection function and fault alarm ability, should not have influence on the normal power supply of external circuit during internal fault, and can report fault message to control centre.

In order to reach the utility model purpose, the utility model is achieved in that by controller (1), carrier meter reading concentrator (3), wireless maintenance interface (4), USB (universal serial bus) (5), capacitor (6), A.C. contactor (8), solid-state relay (9) air switch (11), current transformer (12), Deng composition, it is characterized in that in controller (1), being provided with mainboard control unit (2).

In order to reach second purpose of the utility model, the utility model has been achieved in that in solid-state relay (9) two ends parallel connection A.C. contactor (8), input at device has been installed current transformer (12), is provided with high frequency radio interface module (4) in compensation arrangement.

At the weak point of existing patent and product, this patent improves in following several respects:

1. at solid-state relay two ends parallel connection A.C. contactor, at first allow the solid-state relay conducting, allow the contactor conducting then, make the contact of contactor with the contact short circuit of solid-state relay, thereby the conduction loss of solid-state relay is reduced to the coil loss of contactor itself, has only 20～30W usually.

2. at the input of device current transformer is installed, is made controller have protective capability, can excise problematic capacitor group immediately after detecting the phenomenon of any fault, thereby guarantee that fault is limited in the minimum zone the device internal fault.

3. select high performance microprocessor for use, all functions of power transformer detecting all are made in controller inside.

4. enhancing communication function, not only operating state own and transformer testing result can be uploaded to electrical power distribution automatization system, and can realize three distant (remote control, remote measurement and remote signalling) to transformer and reactive power compensator can also being transferred to distribution management department by telecontrol channel by the result that concentrator is checked meter low pressure carrier wave.

Solution of the present utility model can further be used following description of drawings:

Accompanying drawing 1 is principle of compositionality schematic diagram of the present utility model, wherein figure number (1) controller (11) air switch (2) mainboard control module (12) current transformer (3) carrier meter reading concentrator (13) positioning indicator (4) wireless maintenance interface (14) central processing unit (5) communication interface (15) analog-digital converter (6) capacitor (16) data storage (7) capacitor module (17) control signal output port (8) A.C. contactor (18) control relay isolation output (9) solid-state relay (19) program storage (10) fuse (20) communication serial port

Describe the utility model in detail below in conjunction with accompanying drawing:

The utility model is made of a plurality of parts that are installed in the casing, mainly comprise (12) such as controller (1), carrier meter reading concentrator (3), wireless maintenance interface (4), communication interface (5), capacitor module (7), air switch (11), current transformers, can be equipped with the capacitor module of right quantity in casing as required.Line between each capacitor module is the same, therefore can carry out the expansion of capacity at an easy rate.

The novel controller (1) of this use is made of a plurality of inner function modules, the circuit structure of controller comprises mainly that mainly isolating delivery outlet (18), communication by central processing unit (14), analog to digital converter (15), positioning indicator (13), data storage (16), program storage (18), control signal output ends mouth (17), control signal relay forms with serial port (20) etc. as shown in Figure 3.The inner power down data holding circuit in addition of controller can make sampled data keep certain hour after power failure.

1 pair of operation principle of the present utility model is described below in conjunction with the accompanying drawings: the power supply of device is introduced by the low-pressure side of distribution transformer, power input by this device enters, at first pass through current transformer (12), enter air switch (11) then, after coming out, air switch gives each capacitor module (7) with power distribution by bus, the internal structure of capacitor module as shown in Figure 2, it is made up of fuse (10), solid-state relay (9), A.C. contactor (8), metallization self healing capacitor (6) etc.Connect with ac bus after solid-state relay and the capacitors in series, by the input of solid-state relay control capacitor or withdraw from, thereby change the condenser capacity that inserts electric power system, just changed the reactive power of device output.The corresponding contact parallel operation of the contact of A.C. contactor in capacitor module (8) and solid-state relay (9) can reduce the solid-state relay conduction voltage drop like this, thereby reduces the power loss of solid-state relay.When breaking down and when causing super-high-current, fast acting fuse (10) can prevent the expansion of short trouble, effectively the safety of assurance device in device inside.Controller (1) needs the voltage and current signal of input transformer low-pressure side when working, also comprise the sampled signal of device input current transformer (12).At first input signal is carried out analog-to-digital conversion by A/D converter (15), by microprocessor data are carried out obtaining after the calculation process numerical value of the effective value of transformer voltage, electric current and active power, reactive power again, can also obtain the electric energy numerical value of load consumption to the integration of active power.According to sampled result to electric signal, can calculate this device needs the reactive power of input, send control signal according to predefined control law then and give solid-state relay (9), just a capacitor module has been inserted electric power system after the solid-state relay conducting, actual conditions according to load once can insert one or more capacitor modules.If the excessive phenomenon of operating current takes place; at first the fuse by each capacitor module moves; if having regular event, fuse do not do backup protection by the air switch (11) of input; if air switch is failure to actuate or overcurrent numerical value does not reach and opens operating value; then do last protection by controller; about 2 second controls in back take place overcurrent will send the excision instruction, and all capacitor modules are deactivated.

This use is novel to have powerful remote measurement, remote signalling, distant control function and ability to communicate, the working status parameter of state parameter of device own and transformer can detect and long-distance transmissions to the control centre, the high side switch that the control centre also can the remote control transformer moves; Concentration of transmissions was to the control centre after the carrier meter reading concentrator of installing in the device can reduce pressure user electric quantity data acquisition, and general serial line interface can satisfy the requirement of different communication channels; In order to debug with easy to maintenance, inside also has been equipped with wireless maintenance interface (4), need not have a power failure and open chamber door, and the staff just can monitor and be provided with the advantage of parameter to the state of device on ground, can be widely used in the distribution system.

Claims

1. low-voltage comprehensive reactive power compensator, by controller (1), carrier meter reading concentrator (3), wireless maintenance interface (4), USB (universal serial bus) (5), capacitor (6), A.C. contactor (8), solid-state relay (9), air switch (11), current transformer (12) waits composition, it is characterized in that being provided with in controller (1) mainboard control unit (2).

2. low-voltage comprehensive reactive power compensator according to claim 1 is characterized in that in solid-state relay (9) two ends parallel connection A.C. contactor (8).

3. low-voltage comprehensive reactive power compensator according to claim 1 is characterized in that at the input of device current transformer (12) being installed.

4. low-voltage comprehensive reactive power compensator according to claim 1 is characterized in that being provided with high frequency radio interface module (4) in compensation arrangement.