CN1599187A

CN1599187A - Electric energy mass and powerless compensation combination controller

Info

Publication number: CN1599187A
Application number: CN 200410009536
Authority: CN
Inventors: 孙元章; 李国杰; 黎雄
Original assignee: Tsinghua University
Current assignee: Tsinghua University
Priority date: 2004-09-10
Filing date: 2004-09-10
Publication date: 2005-03-23
Anticipated expiration: 2024-09-10
Also published as: CN100347922C

Abstract

The quality of power supply and the reactive compensation combination controller belongs to the field of the dynamic voltage compensation and reactive compensation technology of the power system. It adopts the design of the series-parallel connection, connects with the silicon controlled in series and with the inverter parallelly through the measure and control circuit centered on the DSP in normal working and increases the reliability and efficiency. When the voltage falls, the inverter will send out the corresponding sine wave to compensate the needed quantity of the voltage and thus can guarantee the failure free operation of users' equipments. When users' reactive demand is excess or negative and affects the level of the voltage, it will devote the shunt-wound general-patching capacitor in stages or get rid of it to compensate the reactive. When the interphase reactive is not balanced, solve the problem of the imbalanced interphase reactive through the casting control to the shunt-wound capacitor. It also solves the problems of fall of the alternating voltage and the reactive compensation in the power system and improves the level of the voltage.

Description

Integrated controller of eactive compensation and power quality

Technical field

Integrated controller of eactive compensation and power quality belongs to Electrical Power System Dynamic voltage compensation and reactive power compensation technology field.

Background technology

Economy reaches the requirement of quality of power supply level just high more all the more, power quality problem not only can bring very big economic loss to industrial quarters, cause production cost to increase as stopping work and restarting, the damage equipment that is quick on the draw, scrap semi-finished product, reduce product quality etc., and can endanger the normal operation of electric power system, EPRI-Electric Power Research Institute (EPRI) studies show that, power quality problem causes U.S.'s industry in data every year, on material and the productivity with a toll of 30,000,000,000 dollars, along with developing rapidly of China's high-technology industry, requirement to quality of power supply level is also more and more higher, it is wherein subject matter that voltage is subside, voltage is subside the stable problem that not only can cause electric power system, also can influence the operate as normal of power consumption equipment, electric power system fault, large-size machine starts, subcircuits short circuit etc. can cause that all voltage subsides, the feature that voltage is subside is that supply voltage drops to 10% to 90% normal voltage value suddenly and continues 0.5 to 50 cycle, remaining system voltage when the voltage dynamic compensator of tandem type utilizes voltage to subside has solved voltage effectively and has subside problem;

And along with the sustainable growth of China's economy, power load increases sharply, user's reactive requirement increases substantially, thereby bring the quadrature network loss day by day seriously to influence voltage levvl again, this brings more serious problem to the basis very serious China's network system of short of electricity, and therefore how wastage reducing and energy saving seems more urgent, adopt the method for shunt capacitor can solve idle network loss problem, to and ally the communists and mend capacitor and carry out the classification switching, thereby reduced reactive loss, improved voltage levvl; When alternate idle when uneven,, solved alternate idle unbalanced problem by parallel connection being divided the phase-splitting switching control of mending capacitor;

Voltage dynamic compensator and Static Var Compensator that independent design is arranged at present both at home and abroad, the design have proposed research and development and design integrated controller of eactive compensation and power quality first.

Summary of the invention

The object of the present invention is to provide a kind of integrated controller of eactive compensation and power quality;

The integrated controller of eactive compensation and power quality that the present invention proposes is a kind of connection in series-parallel design, under operate as normal, conducting simultaneously of the positive brachium pontis of inverter or the conducting simultaneously of negative brachium pontis, serial connection controllable silicon and inverter parallel connection power to the load like this, it is also high to have improved reliability and efficient, it is also can proof load when even open circuit takes place controllable silicon unaffected, when voltage is subside, corresponding sinusoidal wave by inverter output to compensate required voltage, the sine wave and the system voltage of output are cascaded, make user's terminal voltage normal, influence, guaranteed the normal operation of subscriber equipment thereby make subscriber equipment not subside by voltage; When user's reactive requirement is excessive, cause quadrature network loss increase and influenced voltage levvl that at this moment the common benefit capacitor with parallel connection carries out the classification input with compensating reactive power, has reduced reactive loss; And when user's reactive requirement has influenced voltage levvl for bearing, at this moment the common benefit capacitor with parallel connection carries out the classification excision, improved voltage levvl by compensating reactive power, when alternate idle when uneven, by parallel connection being divided the phase-splitting switching control of mending capacitor, solved alternate idle unbalanced problem;

The integrated controller of eactive compensation and power quality of connection in series-parallel design had both solved in the electric power system alternating voltage and had subside (moment decline) problem, compensated idlely again, had reduced the problem of idle network loss, had improved voltage levvl;

Its characteristics are as follows:

1. can solve the voltage problem of subsideing and improve the quality of power supply, can reduce idle network loss by reactive power compensation again, further improve voltage levvl;

2. connection in series-parallel design;

3. the quality of power supply and reactive power compensation are carried out Comprehensive Control;

4. serial connection controllable silicon and inverter parallel, high reliability and high efficiency;

The invention is characterized in:

It is a kind of series-parallel three-phase electric energy quality and reactive power compensation integrated controller, contains:

Measure and control circuit, comprise:

DSP is a data signal processor;

The supply voltage instrument transformer of serial connection is PT and filter circuit mutually, and the input of described supply voltage instrument transformer links to each other with supply voltage, and the output of described filter circuit links to each other with the supply voltage measuring-signal input of described DSP;

The load voltage instrument transformer of serial connection is PT and filter circuit mutually, and the input of described load voltage instrument transformer links to each other with load voltage, and the output of described filter circuit links to each other with the load voltage measuring-signal input of described DSP;

The load current instrument transformer of serial connection is CT and filter circuit mutually, and the input of described load current instrument transformer is a load current signal, and the output of described filter circuit links to each other with the load current measuring-signal input of described DSP;

The voltage sensor and the filter circuit of mutual serial connection, the input of described voltage sensor is a d. c. voltage signal, the output of described filter circuit links to each other with the dc voltage measurement signal input part of described DSP;

Serial connection controllable silicon whenever is made of two controllable silicon inverse parallels, and three-phase has three groups of inverse parallel controllable silicons, and they are serially connected with in three phase mains and the load circuit, and their control end links to each other with the serial connection controllable silicon control signal output ends of described DSP;

The energy storage branch road is formed by energy storage battery serial connection, three-phase by three groups independently the energy storage branch road constitute every phase energy storage branch road two ends and following this inverter direct-flow side two ends phase and connecting mutually;

Inverter, three-phase have three groups of independently inverters, and every phase inverter is that IGBT forms H type full-controlled bridge structure by four insulated door grid thyristors, described every phase inverter with this mutually energy storage battery be in parallel; The control end that each insulated door grid thyristor is IGBT links to each other with the control IGBT signal output part of above-mentioned DSP;

Filter circuit, every phase filter circuit is made up of ac filter inductance and electric capacity, and the tie point between this filter inductance and the filter capacitor links to each other with that contact that this controllable silicon that is in series links to each other with load; The other end of filter inductance links to each other with the ac output end of above-mentioned inverter, and the other end of filter capacitor links to each other with the ac input end of above-mentioned inverter;

And the benefit controllable silicon of allying the communists, form capacitor with following and the benefit capacitor of allying the communists and mend circuit altogether, can constitute for 12 grades by 3 grades or as many as, every grade has two groups of inverse parallel controllable silicons, A, the C that two groups of inverse parallel controllable silicons are serially connected in respectively and load links to each other and following and ally the communists and mend between the capacitor, and ally the communists and mend the silicon controlled control end and link to each other with the control of above-mentioned DSP and the benefit silicon controlled signal output part of allying the communists;

And the benefit capacitor of allying the communists, for triangle is a connection, its two ends link to each other with above-mentioned and the benefit silicon controlled corresponding end of allying the communists respectively; The B that the other end directly links to each other with load links to each other;

Mend controllable silicon in parallel the branch, form capacitor branch benefit circuit with the following benefit capacitor that divides in parallel, can or multistagely constitute by 1 grade, every grade has three groups of inverse parallel controllable silicons, A, the B that three groups of inverse parallel controllable silicons are serially connected in and load links to each other, C three-phase are mended between the capacitor with following branchs in parallel, and the control parallel connection branch benefit silicon controlled signal output part of mending silicon controlled control end and above-mentioned DSP that divides in parallel links to each other;

Mend capacitor in parallel the branch, and for star is the Y connection, its three end is mended the silicon controlled corresponding end with above-mentioned branch in parallel respectively and linked to each other, and common port links to each other with neutral point.

Between described serial connection controllable silicon and power source loads, respectively be connected in series an isolating switch, between power supply and load, be connected in series a by-pass switch.

The direct connection in series-parallel of the present invention is 380 volt of one side in voltage low pressure, under operate as normal, powers to the load by controllable silicon and inverter parallel connection, and reliability height and efficient are also high; And when voltage is subside, can protect power consumption equipment; When excessive, classification drops into three-phase and mends capacitor altogether to reach the purpose of effective compensating reactive power, further reduces network loss when idle, and when negative, classification is withdrawed from three-phase and mended capacitor altogether to reach the purpose of effective compensating reactive power, further improves the system voltage level when idle; Idle when uneven when three-phase, the switching three-phase divides mends capacitor reaching the idle purpose of active balance, thereby improves system voltage.

Description of drawings

Fig. 1. the integrated controller of eactive compensation and power quality schematic block circuit diagram.

Fig. 2. measure and the control circuit theory diagram.

Fig. 3. the integrated controller of eactive compensation and power quality schematic block circuit diagram of band by-pass switch.

Embodiment

In the empty frame of Fig. 1 is the design principle figure of integrated controller of eactive compensation and power quality 20, every mutually required energy is provided by

energy storage battery

7,8,9 respectively between the amortization period, every phase independent compensation, prolonged the life-span of storage battery like this, under operate as normal, serial connection controllable silicon and inverter parallel connection power to the load, and have had high reliability like this, and efficient is also high simultaneously;

Shown in the empty frame 20 of Fig. 1, integrated controller of eactive compensation and power quality 20 is by serial connection

controllable silicon

1,2,3,

inverter

4,5,6,

energy storage battery

7,8,9,

ac filter inductance

10,12,14, ac filter

electric capacity

11,13,15, and ally the communists and mend controllable silicon 16, and ally the communists and mend capacitor 17, mend controllable silicon 18 in parallel the branch, mend capacitor 19 in parallel the branch, and measure and control circuit 24 (see figure 2)s formation, below introduces each part in detail:

1,2,3 is three groups of antiparallel serial connection controllable silicons, and during operate as normal, supply voltage mainly offers load by them, they and inverter parallel, and when voltage was subside, serial connection controllable silicon disconnected;

4,5,6 is three separate inverter units, each inverter is formed H type fully controlled bridge structure by four IGBTs (insulated door gridistor), during operate as normal, conducting simultaneously of the positive brachium pontis of inverter or the conducting simultaneously of negative brachium pontis, parallel connection powers to the load with serial connection controllable silicon like this, has improved reliability, when the supply voltage instantaneous variation surpasses set point, according to required voltage, inverter is exported corresponding pulse-width modulation PWM signal;

7, the 8, the 9th, three groups of energy storage batteries independently are used for storage power so that required during compensation;

10, the 12, the 14th, the ac filter inductance, 11,13,15 o'clock ac filter electric capacity, every cross streams filter circuit is 10 and 11 by ac filter inductance and electric capacity, 12 and 13,14 and 15 form respectively, and voltage is subside the pwm signals of inverter 4,5 between the amortization period or 6 outputs behind filter circuit, obtains sinusoidal voltage, this sinusoidal voltage is connected in series to and compensates required voltage in the electrical network, the influence that makes load voltage not subside by supply voltage;

16,17 composition shunt capacitors are mended circuit altogether, they are respectively two groups of inverse parallel controllable silicons and the triangle and the benefit capacitor of allying the communists, can or cause 12 grades more and constitute by 3 grades to reach the purpose that classification is mended altogether, when idle when excessive, classification drops into three-phase and mends capacitor altogether to reach the purpose of effective compensating reactive power, further reduces network loss, when idle when negative, classification is withdrawed from three-phase and is mended capacitor altogether to reach the purpose of effective compensating reactive power, further improves the system voltage level;

18,19 form shunt capacitor branch benefit circuit, they are respectively that three groups of inverse parallels divide benefit controllable silicon and star to mend capacitor in parallel the branch, idle when uneven when three-phase, the switching three-phase divides mends capacitor reaching the idle purpose of active balance, thereby improves system voltage;

Goodbye Fig. 1～3:

When powering on, by-pass switch closes automatically, manual closing two isolating switches at this moment, and whole device is started working; During operate as normal, measurement and control circuit 24 send control signal and make conducting simultaneously of the positive brachium pontis of inverter or the conducting simultaneously of negative brachium pontis, and serial connection controllable silicon and inverter parallel connection power to the load like this; Measure and control circuit 24 real-time monitoring supply voltages, when detecting supply voltage above set point, turn-off serial connection controllable silicon, measurement and control circuit 24 send control signal and make inverter 4,5 or the corresponding pwm signal of 6 outputs, this pwm signal obtains required sinusoidal voltage behind ac filter circuit, this sinusoidal voltage and supply voltage are superimposed, make load obtain normal voltage, thereby guaranteed the normal operation of subscriber equipment; Measure and control circuit 24 real-time sampling load voltage and load currents, try to achieve the load reactive power by calculating, when load (user) when reactive requirement is excessive, send control signal by real-time monitoring supply voltage 24 the common benefit capacitor of parallel connection is carried out the classification input with compensating reactive power, thereby reduced reactive loss; And when the load reactive requirement has influenced voltage levvl for bearing, send control signal by real-time monitoring supply voltage 24 the common benefit capacitor of parallel connection is carried out the classification excision, improved voltage levvl by compensating reactive power, when alternate idle when uneven, send control signal by real-time monitoring supply voltage 24 and divide the benefit capacitor to carry out the control of phase-splitting switching, solved alternate idle unbalanced problem parallel connection;

In actual applications, design as shown in Figure 1 can directly be connected in series in the power supply of load, also can be connected in series to together in the power supply of load to maintain easily, to overhaul, as shown in Figure 3 with by-pass switch 21, isolating switch 22,23.

Claims

1. integrated controller of eactive compensation and power quality, it is characterized in that: it is a kind of series-parallel three-phase electric energy quality and reactive power compensation integrated controller, contains:

Measure and control circuit, comprise:

DSP is a data signal processor;

2. integrated controller of eactive compensation and power quality according to claim 1 is characterized in that: respectively be connected in series an isolating switch between described serial connection controllable silicon and power supply, load, be connected in series a by-pass switch between power supply and load.