CN202218020U

CN202218020U - Phase-control-type reactive power dynamic compensating device

Info

Publication number: CN202218020U
Application number: CN2011203373513U
Authority: CN
Inventors: 孟革生; 侯举贤; 关捷; 石生
Original assignee: JINZHOU WANSHI CAPACITOR COMPLETE SETS OF EQUIPMENT CO Ltd
Current assignee: Jinzhou Wanshi Special Transformer Co., Ltd.
Priority date: 2011-09-09
Filing date: 2011-09-09
Publication date: 2012-05-09
Anticipated expiration: 2021-09-09

Abstract

The utility model provides a phase-control-type reactive power dynamic compensating device composed of a dynamic control device, a dynamic zero passage switch element, multiple groups of filter capacitors and a protection feedback device. It is characterized in that the dynamic control device is composed of a sampling module used for synchronous detection of six groups of signals of three phase voltage signals and three phase current signals on a main low voltage transforming side, a dynamic master control module used for dynamic zero passage switch control of the multiple groups of the filter capacitors according to a volume of a reactive load, a trigger pulse module connected between the dynamic master control module and the dynamic zero passage switch element, a display module connecting with the dynamic master control module to display various running parameters and types of faults appearing in running, a key board input module connecting with the dynamic master control module and a communication interface transmitting signal to the external. The phase-control-type reactive power dynamic compensating device in the utility model solves a problem of reverse nodal point caused by three phase unbalanced loads, improves power factors of each phase to an optimal state, reduces loss of a power grid effectively, and improves the quality of power supply voltage.

Description

The phase control type reactive power dynamic compensation device

Technical field

The utility model relates to a kind of phase control type reactive power dynamic compensation device.

Background technology

In recent years; Non-linear, the asymmetric and impact load of low-voltage network increases rapidly; Cause the quality of power supply of mains by harmonics severe overweight, electrical network to worsen; This will produce following adverse effect: 1, the idle and harmonic current of nonlinear-load generation permeates to the middle and high electric system that is press-fitted in a large number, can not get for a long time administering, and has increased the loss of system.2, asymmetric load has aggravated the degree of unbalance of electrical network.3, impact load (as: rolling mill, welding machine, large-scale punch press etc.) is idle from the electrical network absorption fast, produces voltage fluctuation and flickering simultaneously, reduces the effective output of motor, and the finished product rate is reduced, and shortens service life of equipment.4, harmonic current not only causes the Transformer Winding supplementary load loss; Also cause shell, outer silicon steel sheet and the heating of some securing member; And might cause the seriously overheated of part; Harmonic wave increases transformer noise, and the harmonic current of the transformer of flowing through that harmonic source causes possibly damage transformer under condition of resonance.5, harmonic wave can be sensed on the communication line through capacitive coupling, electromagnetic induction and electrical conductivity, influences calling quality, under extreme case, and threat equipment and personnel's safety.Therefore be necessary that these load or burden without work is carried out the local compensation harmonic administers.

The method of control reactive power is more, and synchronous generator, synchronous motor, synchronous compensator, shunt capacitor etc. are arranged.In above-mentioned several method, shunt capacitor is simple, economical, convenient, and has filter function, so progressively replace first three methods, is the method for extensive use at present.The problem that existing reactive power shunt capacitor compensation arrangement exists is: 1, adopt mechanical contact switching power capacitors such as A.C. contactor, big, the voltge surge Da ﹑ sparking of shoving, vibration and useful life are short.2, employing is thrown and is cut the fixed capacitor group, because of overcompensation, undercompensation appear in load variations, thereby causes the capacitor utilance low, and the power factor of electrical network can not steadily be controlled.3, be all three-phase capacitor interlock switching mode, only be applicable to three-phase balancing load, and be difficult to be suitable for for the unbalanced load of enterprises and institutions such as skyscraper, civilian electricity and rural power system.

The utility model content

The utility model is to solve the problems referred to above that present technology exists; Provide a kind of current collection ability quality-monitoring, reactive power compensation, harmonic wave control in one; Can solve " node " phenomenon that the three-phase imbalance load occurs, each phase power factor is brought up to optimum state, effectively reduce the loss of electrical network; Harmonic voltage, harmonic current in effective inhibition system, quality and the safety and stability of electric power networks and the phase control type reactive power dynamic compensation device of economic operation level of raising supply power voltage.

The utility model is achieved in that by device for controlling dynamically, dynamic operating passing zero element, organizes filtering capacitor more and protect feedback device to form; Its special character is: described device for controlling dynamically be by to main transformer low-pressure side three-phase voltage and three-phase current totally six groups of signals carry out real-time synchronous detecting sampling unit, according to the idle size of load come to many groups filtering capacitor carry out dynamic operating passing zero control dynamic main control unit, be connected the dynamic main control unit and the dynamic display unit of the trigger impulse unit between the operating passing zero element, the fault type that is used for showing various operational factors and emerged in operation of being connected with dynamic main control unit, the keyboard input unit that is connected with dynamic main control unit and outside transmission signals are with the networking control of realization computer and the communication interface composition of management.

This reactive power dynamic compensation device changes the interlock switching of three-phase capacitor into can realize single-phase phase control type structure; Current collection ability quality-monitoring, reactive power compensation, harmonic wave control are in one; The input that can decide capacitor according to the size and the character of reactive power in the electrical network or withdraw from electrical network makes the reactive power in the electrical network be reduced to set point.Drop into the capacitor group constantly in the fracture voltage zero passage during switching; Excise capacitor group function constantly at current over-zero; Realize capacitor group no-flashy-flow and no overvoltage switching, eliminated the harm that system and capacitor equipment is caused by inrush phenomenon, switching overvoltage etc. like this; Can improve simultaneously the quality of voltage of electrical network, the raising electric power system is defeated, the transmittability of converting equipment; Prolong the useful life of capacitor, improved the reactive power compensation precision; Reach the purpose of the loss-reducing and electricity-saving and the realization integrated automation of transformation stations, improve the safety and stability and the economic operation level of electric power networks.This device is applicable to 380V, 50Hz three-phase low-voltage network; Low-voltage power users such as separate unit capacity 200KVA and above outdoor desk-top transformer, chamber, interior distribution station, box-type substation and machinery, mine, railway, chemical industry be can be widely used in and reactive power compensation and electric quantity monitoring carried out; Be the ideal equipment of upgrading urban and rural power grids and construction, it also has the following advantages:

(1) for the electric power system of 380/220V three-phase four-wire system, no matter whether balance all can compensate to cos ф more than 0.98 in load.

(2) can excavate the transformer equipment potentiality significantly, original cos ф≤0.7, overload, drop into this compensation arrangement after, i.e. no longer overload.

(3) can avoid the user to hand over power factor to regulate the electricity charge.For example cos ф=0.65 o'clock can pay 15% less, and for example: adapted 315KVA transformer, 2-4 ten thousand kW.h can economize on electricity every year.

(4) can realize contactless throw-in and throw-off, can be to capacitor " equipotential throw, zero current is cut ", big, the voltge surge Da ﹑ sparking of shoving when thoroughly having overcome in the past mechanical contact switching power capacitor such as A.C. contactor, vibration and useful life short shortcoming.

(5) can realize multiple functions such as " remote measurement ", " remote control ", " remote signalling ", " remote regulating ".

Description of drawings

Fig. 1 is the block diagram of the utility model;

Fig. 2 is the circuit structure diagram of the utility model.

Embodiment

As shown in the figure, the utility model by device for controlling dynamically 1, dynamically operating passing zero element 2, organize filtering capacitor 3 and protection feedback device 4 is formed more.Described dynamic operating passing zero element 2 adopts the high-power silicon controlled rectifier trigger module, organizes filtering capacitor 3 more and is metallization self-healing filtering capacitor.Described device for controlling dynamically 1 is by to main transformer low-pressure side three-phase voltage and three-phase current totally six groups of signal U _a, U _b, U _CAnd I _a, I _b, I _CCarry out real-time synchronous detecting and ripple sampling weekly sampling unit 101, with all data in each electrical network cycle of sampling unit 101 inputs analyze and with operational factor store and according to the idle size of load come to many groups filtering capacitor 3 carry out switching control dynamic main control unit 102, be connected dynamic main control unit 102 and dynamically the trigger impulse unit 103 between the operating passing zero element 2, be connected the display unit 104 of the fault type that is used for showing various operational factors and emerged in operation with main control unit 102; The keyboard input unit 105 that is connected with dynamic main control unit 102 is formed with communication interface 106; Described communication interface 106 is used for outside transmission signals to realize the networking control and the management of computer, further realizes multiple functions such as " remote measurement ", " remote control ", " remote signalling ", " remote regulating ".

Described dynamic main control unit 102 adopts two CPU control forms.

Dynamically main control unit 102 is to be the basis with digital signal processor DSP and VLSI circuit, in each electrical network cycle all data is analyzed.Display unit 104 adopts LCD can show 128 operational factors, and 1～63 subharmonic is analyzed, and the percent value of display bar type harmonic wave, and is in service if break down, prompt alarm, and can the failure judgement type show, be convenient to quick maintenance.

1 pair of three-phase voltage of device for controlling dynamically and three-phase current totally six groups of signals carry out real-time synchronous detecting; Ripple sampling weekly; Use the reactive power that FFT (fast Flourier) algorithm computation system offers load; Come many groups filtering capacitor 3 is carried out switching control according to the idle size of load, reducing the reactive power that load absorbs as much as possible from electric power system 5, and keep three-phase voltage in institute's claimed range.In addition, parameters such as three-phase voltage, electric current, power factor, active power, reactive power are detected and add up, these parameters are uploaded to main website through communication interface 106.

Be to guarantee the precision of detection signal, this dynamic apparatus adopts the synchronous sampling mode of following the tracks of zero crossing, and to because the time delay of sampling is carried out phase compensation.The input or the excision that reach regulation when measured reactive power are during condition, and device for controlling dynamically 1 just sends corresponding switching order, and deciding according to the size of reactive power is one group of switching, two or more groups capacitor.

It is pointed out that switching to many groups filtering capacitor 3 is to trigger when electric current and voltage is crossed null value or turn-off the thyristor in the dynamic operating passing zero element 2 in electric power system ((A, B, C, N)), to reduce impact to thyristor and system.If the voltage of electrical network surpasses or be lower than the upper and lower bound value of defined, device for controlling dynamically 1 will excise operation to many groups filtering capacitor 3 by the delay time of setting.

Claims

1. phase control type reactive power dynamic compensation device; By device for controlling dynamically, dynamically the operating passing zero element, organize filtering capacitor and the protection feedback device is formed more; It is characterized in that: described device for controlling dynamically be by to main transformer low-pressure side three-phase voltage and three-phase current totally six groups of signals carry out real-time synchronous detecting sampling unit, according to the idle size of load come to many groups filtering capacitor carry out dynamic operating passing zero control dynamic main control unit, be connected the dynamic main control unit and the dynamic display unit of the trigger impulse unit between the operating passing zero element, the fault type that is used for showing various operational factors and emerged in operation of being connected with dynamic main control unit, the keyboard input unit that is connected with dynamic main control unit and outside transmission signals are with the networking control of realization computer and the communication interface composition of management.