CN102646986B - Magnetically controlled reactor controller and method thereof - Google Patents

Abstract

The invention discloses a magnetically controlled reactor controller and a method thereof. The magnetically controlled reactor controller comprises a controller module, wherein the controller module has a DSP (digital signal processor)+ARM (advanced RISC machine) structure, the DSP and the ARM are connected through a double-port RAM (random access memory), and the controller module is respectively connected with an analog quantity module (1) and an electric signal output unit; the analog quantity module comprises an AD (analog-digital) chip, the AD chip is connected with a voltage acquisition device arranged on an outer power grid, the controller module is also communicated with an upper computer, and the controller module and the electric signal output unit are respectively connected with a power source processing module; and the electric signal output unit is connected with a pulse transformer in a magnetically controlled reactor. The invention has the beneficial effects that reactive power and voltage parameters of the power grid can be detected quickly and accurately; the operation states (paralleling, separation and disconnection) of a transformer substation can be automatically detected and adapted; and corresponding control strategies can be adopted according to a control target (reactive power or voltage) for accurate control.

Description

Magnet controlled reactor controller and method thereof

Technical field

The present invention relates to a kind of reactor controller and method thereof, relate in particular to a kind of magnet controlled reactor controller and method thereof.

Background technology

Along with the development of Chinese national economy, the demand of electric power is increasing, and the idle pollution of the generation of load is also increasing.China is vast in territory, energy skewness, " transferring electricity from the west to the east, the fundamental state policy [5] of north and south Hu Gong”Shi China power system development.This has determined that China's electric power system power transmission network is huge, has a large amount of long-distance transmission lines.Under the condition of large electrical network, how electric energy is transported to safely and efficiently to the load center at distribution system place from power plant, how for user provides high-quality electric energy, how to effectively reduce the idle pollution to electrical network, guarantee that the safe and highly efficient operation of electrical network becomes one of of paramount importance research topic in electrical engineering field.

In electrical network, have a large amount of asynchronous motors, transformer, power electronic equipment, these equipment will consume a large amount of reactive powers.If these reactive powers can not be compensated in time, can be to the efficiency of electrical network, safety, stable having a negative impact.So producing, the research and development of the research of reactive power compensation theory and high-performance reactive-load compensation equipment just put on schedule.

The theory of reactive power compensation relates to the each side problem from system and user, and the problem relevant with the quality of power supply especially, because most power quality problem can be eased or thoroughly solve by reactive power is suitably controlled.Conventionally, the problem of reactive power compensation can be from the viewpoint of two: load compensation and voltage support.The object of load compensation will improve system power factor exactly, thus the active power that symmetrical alternating current electric power system produces, and eliminate the harmonic wave that high-power variation nonlinear-load produces.The target of voltage support is exactly the voltage fluctuation that will reduce transmission line ends.The reactive power compensation of transmission system is to improve AC system stability by improving the maximum transmitted ability of active power, and is conducive to keep the voltage stabilization of electric power systems at different levels.It can improve high voltage direct current transmission conversion terminal capabilities, improves efficiency of transmission, controls Steady state and transient state overvoltage, avoids system crash.

Series and parallel connections reactive power compensation is commonly used to improve the intrinsic electrical characteristic of AC electric power systems.What series compensation changed is the parameter of transmission system or distribution system, and shunt compensation change is the equiva lent impedance of load.The two can control effectively to the reactive power flow of system, thereby improves the performance of whole AC electric power systems.

The classification of reactive power compensation and development

What in reactive power compensation, develop is early stage, and synchronous compensator is being played the part of a dominant role aspect voltage stabilization and idle control.From principle angle, synchronous compensator is exactly the synchronous machine being connected with electric power system.After compensator operation, can produce or absorb the reactive power that alternating current circuit needs.By suitable automatic magnetic exciting circuit, phase modulation function provides continuous reactive power.Synchronous compensator take that to improve the stability of a system be object conventionally, is used in compartment system and transmission line, the in the situation that of load variations, keeps voltage to change in allowed limits.Yet; synchronous compensator takies larger space; need frequent starting and protective device; and it has increased short circuit current; can not compensate fast-changing load; loss and cost are more much bigger than Static Var Compensator, and its advantage is only the high overload ability having in short-term, seldom use now.

Within 1914, improve power factor of electric network first with shunt capacitor, shunt capacitor produces leading current the lagging current of load generation is compensated.The many factors that the selection of shunt capacitor need to be considered, what wherein need emphasis consideration is the idle size of hysteresis that load produces.If load changes, idlely also can fluctuate in the larger context, so the compensation of fixed capacitor group tends to cause mend or owes and mends.Can change reactive power compensation amount by switch on-off capacitor, according to total reactive requirement, drop into or excise capacitor group.The smoothness of controlling depends on the group number of switched capacitor.Yet, rely on the method response time of mechanical switch or contactor switching capacitance long and unreliable, they also can produce larger impulse current simultaneously, need to often safeguard.

Static Var Compensator (Static Var Compensator-SVC) is the class fast reactive adjusting device that grows up the external seventies, is successfully applied in the compensation of the loads such as electric railway, metallurgy, electric power, mining and high energy acclerator.This class device in the rapidity, the diversity of function that regulate, the aspects such as economy of the reliability of work, investment and operating cost have obvious advantage than synchronous compensator, can obtain good technical economic benefit, thereby obtain development faster at home and abroad.

The SVC of main flow mainly contains three classes: thyristor switchable capacitor (Thyristor Switched Capacitor, be called for short TSC), thyristor-controlled reactor (Thyristor Controlled Reactor, be called for short TCR), magnet controlled reactor (Magnetic valve Controllable Reactor is called for short MCR).

Although TSC can only grouping switching capacitor, can not regulate continuously reactive power, to control simply, cost is lower, and without harmonic current, the low-voltage load end that is adapted at electrical network disperses reactive power compensation.

TCR can smooth adjustment capacity and response speed very fast, in the reactive power compensation of medium voltage electricity circuit (6～35KV), obtained extensive application.But TCR directly controls reactor output current by controlling thyristor phase-triggered angle, output current distortion is very serious, and waveform indention, is a very large harmonic source, must move with filtering capacitor group (Filter Capacitor is called for short FC) simultaneously.A large amount of uses of TCR, can cause the significantly decline of the quality of power supply, and bring new threat to the safe operation of electrical network.In addition, in TCR system, thyristor and reactor, under same voltage, have limited its application on 110kV and above electrical network.

MCR is by the magnetic saturation of the excitatory change iron core of control loop DC control electric current (being working point), thereby reaches the object of the idle output of smooth adjustment.The version of MCR has a variety of, and characteristic difference is also larger.In recent years research shows, having application prospect MCR type is most two kinds of magnetic valve type and iron core split types.Compare with TCR, the voltage that the control thyristor of MCR bears only has 2% left and right of rated voltage, and its electric current is also only required specified control electric current, and the electric current and voltage of major loop will partly be born by reactor.This can make MCR be applied to any electric pressure, has avoided by the voltage of thyristor and capacity and the variety of issue bringing.And the harmonic performance of MCR output current is better than TCR, be conducive to the safe and highly efficient operation of electrical network.The manufacture of MCR is simple, and the design of magnet valve makes the efficiency of MCR obtain significantly improving in addition, and noise significantly reduces.From economy, consider, MCR is simple in structure, low price, and floor space is little.Various advantages based on above-mentioned, has the trend of using MCR to substitute TCR in a lot of fields.

Static reacance generator (Static Var Generator is called for short SVG) is a kind of modern power electronic reactive power compensator, and SVG only need to maintain its voltage compared with the capacitor of low capacity in its DC side and get final product [30].SVG, by suitable control, can make it send reactive power, is capacitive character, also can make its absorbing reactive power, is inductive.SVG is a kind of advanced person's modern compensation arrangement, if adopt multiplex or PWM control technology, can make its output current harmonics composition less and be applied to high voltage appearance grade, and shortcoming is can only compensating reactive power electric current, can not compensation harmonic electric current.

Active Power Filter-APF (Active Power Filter is called for short APF) is a kind of for dynamically suppressing the novel electric power electric device of harmonic wave, compensating reactive power.The harmonic wave that it can all change frequency and size and the reactive power of variation compensate, and the variation of target compensation are had to the response speed being exceedingly fast.For APF, what need at present solution is the production domesticization of (1) core devices; (2) reduce costs; (3) solve high-voltage applications integrity problem.If these problems are well solved, APF will become one of optimal selection improving power grid quality.

SVC is most widely used general, reactive-load compensation equipment [31-33] that technology is the most ripe in current various reactive-load compensation equipment.Reactive power compensation technology based on full control device (SVG, APF) exists device core technology by foreign corporation monopolization, the shortcoming such as cost is high, high-voltage applications technology is not mature enough, within a period of time from now on, in mesohigh field, can't replace SVC.

In at present main three kinds of SVC (TCR, MCR and TSC), MCR has the advantage of obvious technology and price in mesohigh reactive power compensation field, is applicable to large-scale promotion and uses.High performance controller can make the performance of MCR be greatly enhanced, and this makes the high-performance MCR controller of a set of applicable commercial Application of design and development become a very significant job.

1.2 research trends and existing problems

MCR is the operating experience of existing more than 20 year abroad, has the MCR of the 35～500kV of cover more than 50 electric pressure to apply in the engineering of Russia, member country of the Commonwealth of Independent States and Brazil.Within 2005, Russia has developed 500kV, 180Mvar three-phase magnetron reactor [34-37].Owing to recognizing the advantage of MCR in high-power field, European many countries also start MCR to carry out deep research.

At home, in early 1990s, carried out the research of this respect, successfully worked out the magnetic valve type compensation arrangement and the arc suppression coil that are applied to power distribution network, and put into operation in a plurality of electric railways Traction Station.Colleges and universities have also launched the research of this respect, and have obtained greater advance.Manufacturer is studied and produces as a trial superhigh pressure MCR and superhigh pressure high-impedance transformer formula controlled reactor (Transformer Type Controlled Shunt Reactor is called for short TCSR).

In April, 2006, relevant unit carries out exploitation and the application study of 110 kilovolts of controlled reactors.In April, 2007, develop 110 kilovolts of MCR of First, and passed through delivery test and relevant type approval test, in June, complete Installation and Debugging and put into operation successfully.MCR model machine (iron core split type) by the 500kV three-phase 40Mvar developing in 2006, by shop test, transports on-the-spot and trial run in April, 2007 to.

The shortcomings such as at present, the MCR controller that most domestic producer researchs and produces is mostly to take 80C196 as core, exists control rate slow, and sampling precision is not high enough, and man-machine interface is friendly not, have seriously restricted the performance of MCR performance and the popularization of product.In addition because MCR is applied in the technology that belongs in the world newer, still belong at home theory stage or trial run stage, deeply launch not yet on a large scale, many ins and outs do not relate to.Cause technical also immature.

In reality, the analytical work in theory of reactor controller is more, design in enforcement is comparatively complicated, adopts optical fiber communication more, causes enforcement and maintenance difficulties higher, in the situation that particularly high pressure or ultra high voltage field have higher requirements to insulating requirements, that really puts into practice is less.

Summary of the invention

Object of the present invention is exactly, in order to address the above problem, to provide a kind of magnet controlled reactor controller, and it has reliable, and high-performance, cost are low, are applicable to commercial Application, and MCR controller architecture is reasonable, and the performance of MCR can access maximum performance.The advantage of easily implementing.

To achieve these goals, the present invention adopts following technical scheme:

A controller, it comprises controller module, and described controller module is DSP+ARM framework, and described DSP is connected by dual port RAM with ARM, and controller module is connected respectively with signal of telecommunication output unit with analog module 1; Described analog module comprises AD chip, and the voltage collecting device that described AD chip is provided with external electrical network is connected, described controller module also with upper machine communication, described controller module, signal of telecommunication output unit are connected with power supply processing module respectively; Described signal of telecommunication output unit is connected with the pulse transformer in magnet controlled reactor.

Described DSP is connected with power supply processing module respectively with ARM; Described analog module comprises AD chip, described DSP input is connected with AD chip, DSP output is connected with signal of telecommunication output unit, and described DSP is also connected with nonvolatile memory with clock chip, and the ARM in described controller module and host computer are by serial or network interface communication.

Described DSP is connected with status indicator lamp.

Described voltage collecting device is voltage transformer, and the current transformer that described AD chip is also provided with external electrical network is connected.

Described signal of telecommunication output unit comprises insulating cement plank, at insulating cement plank, is provided with binding post, and described binding post one end is connected with DSP output pin, and the other end is connected with the pulse transformer in magnet controlled reactor by twisted-pair feeder or shielding conductor.

Described dsp chip is TMS320F28335; Dsp processor also connects JTAG chip internal test interface; Described ARM chip S3C2410A.

Described AD chip is connected with CT current transformer with outside PT voltage transformer.

A controller control method, it comprises the steps

1) voltage sensor, the current sensor of DSP by electrical network carries out AC sampling and obtains current system state; Described voltage sensor, current sensor carry out line voltage and line current collection to power network line, adopt two kinds of digital filter series connection associating filtering modes of comparison expression digital filter and integration type digital filter in described AC sampling in DSP; Subsequently to filtered line voltage and line current carry out digital phase-locked frequency multiplier sampling, by AD, change interrupt service routine the line voltage effective value of electrical network, line current effective value, active power, reactive power, apparent power, each quantity of state of power factor calculated;

2) by the touch screen operation being connected with ARM, select voltage adjustment or power factor to adjust one of two kinds of control models; The line voltage gathering or line current sinusoidal signal obtain synchronizing signal by crossing zero balancing, using zero crossing synchronizing signal as phase shift benchmark; DSP calculates the phase shifting angle that the every phase of current time should be exported; Described control program comprises the closed loop control algorithm based on DSP;

3) DSP according to the phase shift angle of calculating in conjunction with phase shift benchmark, and the magnetic valve type controllable reactor that will control is specially single-phase or three-phase, single-phase or the three-phase triggering signal triggering signal of corresponding generation, utilize signal of telecommunication pulsed drive pulse transformer wherein to control magnetic valve type controllable reactor, pulse transformer sends pulse train and ensures that the upper corresponding thyristor of magnetic valve type controllable reactor MCR excites reliably;

Described digital phase-locked frequency multiplier sampling comprises:

I), DSP has trapping module CAP to obtain current demand signal frequency, the magnetic valve type controllable reactor of controlling is as required specially single-phase or three relative trapping module CAP and accepts or rejects use; Described power system frequency is the inverse of time difference of twice positive going zeror crossing point of institute's survey line voltage; The synchronizing signal of any phase line voltage is input on CAP1 input port, by software, configures, and the hardware of CAP1 catches the time of adjacent twice saltus step, i.e. cycle T; Thereby frequency is asked as f=1/T, the grid line voltage signal frequency using it as first-harmonic; By line voltage signal frequency, the line current frequency of same phase obtains simultaneously;

Ii), the grid line voltage as first-harmonic that sample frequency is set as collecting or line current signal frequency 128 times, the high order harmonic component of need analyzing is 32 times, therefore low pass filter elects 50 * 32=3.2kHz as by frequency, 32 above high order harmonic components of elimination, prevent the aliasing of sampling effectively;

Iii), described digital phase-locked frequency multiplier is to be realized by dsp program, because digital circuit can realize precise synchronization output, so omit feedback element, adopts open-loop design principle; This digital phase-locked frequency multiplier is also referred to as homophase frequency multiplication;

The ADSOC that is input to AD module when synchronizing frequency doubling signal controls on mouth; By software, arrange, make an AD conversion of synchronizing frequency doubling signal rising edge triggering each time, after AD EOC, automatically trigger AD interrupt service routine; The result that in interrupt service routine, storage is sampled each time, then an AC sampling calculating is carried out in every 128 samplings after finishing, by the discrete formula of each physical quantity, calculate line voltage, line current, active power, reactive power, apparent power, the power factor value of electrical network, by dual port RAM and ARM, realize data sharing, as the input variable of controlling and showing;

Described closed loop control algorithm: controller has been taked two kinds of control strategies: user, according to actual conditions, selects different control models by touch screen operation; Voltage adjusts control model and power factor is adjusted control model; Voltage is adjusted control model and be take line voltage as controlled quentity controlled variable, by different reactive currents is provided, by the voltage stabilization of electrical network on given operating voltage point; Power factor is adjusted control model, and to take the power factor of electrical network be controlled quentity controlled variable, by different reactive currents is provided, the power factor of electrical network is stabilized on the power factor point of setting; According to control principle, if take voltage as controlling target, given voltage-regulation desired value, introduces voltage negative feedback; By the line voltage U and the given reference voltage U that detect _refcompare, its deviation is input to PI governing loop, and pi regulator calculates the phase-shift control angle of output, controls the reactive power output size of MCR by circuits for triggering, changes line voltage;

Equally, if will adjust control model with power factor, given power factor regulation desired value, introduces voltage and current feedback, calculates power factor of electric network as negative feedback; Line voltage u and power network current i by detecting, then calculate power-factor angle

with given reference voltage

compare, its deviation is input to PI governing loop; Pi regulator calculates the phase-shift control angle that export, controls the reactive power output size of MCR by circuits for triggering, changes power factor of electric network;

After two kinds of algorithm discretizations, on DSP, realize; The responsive time constant of the time constant of pi regulator and MCR itself adapts;

The line voltage gathering or line current sinusoidal signal obtain synchronizing signal by crossing zero balancing, using zero crossing synchronizing signal as phase shift benchmark, DSP calculates the phase shift angle that the every phase of current time should be exported, DSP is according to phase shift angle and the phase shift benchmark received, produce triggering signal, for the reliable thyristor that triggers, for pulse transformer, adopt trigger impulse is carried out to the method triggering that software homophase carrier wave is subdivided into a plurality of pulse trains.

Utilize dsp program to realize filter circuit; System has been used two kinds of filters: two kinds of filter series connection of comparison expression filter and integration type filter; Integration type filter is realized the low-pass filtering of digital signal, the effectively shake of the signal of filtering and burr, and filtering cut-off frequency is adjustable on a large scale, comparison expression filter is applicable to the higher situation of cut-off frequency, and the two is in conjunction with the input processing strengthening signal of interest;

Take sampling thheorem theory as basis, requiring sample frequency is the more than 2 times of highest frequency in measured signal frequency spectrum, adopt hardware synchronization sampling method to measured signal, be that synchronized sampling method is exactly the complete cycle of uniform sampling uniformly-spaced, between sampling number N, meet relational expression T=N Δ t in measured signal cycle T, sampling time interval Δ t and a cycle, that is: sample frequency be measured signal frequency N doubly.

Grid frequency measurement circuit measuring goes out current demand signal frequency, DSP calculates the frequency multiplication cycle by 128 frequencies, the synchronizing frequency doubling signal of generation and input signal homophase, has so just realized the homophase of supplied with digital signal times frequency sampling, and the ADSOC that sampled signal is input to DSP triggers AD interruption;

Described grid frequency measurement circuit is to utilize DSP trapping module CAP that the synchronous signal acquisition of line voltage is configured by software, and CAP can catch the time of adjacent twice saltus step, i.e. cycle T; Power system frequency is exactly the inverse of time difference of twice positive going zeror crossing point of surveyed phase voltage; This time difference is the cycle of alternating voltage amount namely; Thereby frequency can be asked as f=1/T.

It is mouthful upper that the ADSOC that synchronizing frequency doubling signal is input to DSP controls, and by software, arranges, make synchronizing frequency doubling signal each time rising edge trigger an AD conversion, after AD EOC, automatically trigger AD interrupt service routine;

The result that in described AD interrupt service routine, storage is sampled each time, then an AC sampling calculating and the closed loop control algorithm based on DSP are carried out in every 128 samplings after finishing, simultaneously by counter O reset, wait for the circulation after 128 samplings of next round finish, for sampling, to alternating voltage U, electric current I, active-power P, reactive power Q, power factor

discretization is carried out in the synchronous AC sampling of apparent power electric parameter, calculate voltage, electric current, active power, apparent power, reactive power, the power factor of electrical network, described AC sampling is calculated as the discrete formula by each physical quantity, calculate voltage, electric current, active power, reactive power, apparent power, the power factor value of electrical network, as the input variable of controlling and showing;

Described alternating voltage U, electric current I discrete formula

Current effective value, voltage effective value, be defined as:

$U=\sqrt{\frac{1}{T}{\∫}_0^T{u}^2\left(t\right)\mathrm{dt}}---(0-1)$

$I=\sqrt{\frac{1}{T}{\∫}_0^T{i}^2\left(t\right)\mathrm{dt}}---(0-2)$

In formula:

T---be the sampling period;

U (t)---instantaneous voltage;

I (t)---current instantaneous value.

By after above two formula discretizations:

$U=\sqrt{\frac{1}{N}\underset{k=0}{\overset{N-1}{\mathrm{\Σ}}}u{\left(k\right)}^2}---(0-3)$

$I=\sqrt{\frac{1}{N}\underset{k=0}{\overset{N-1}{\mathrm{\Σ}}}i{\left(k\right)}^2}---(0-4)$

In formula:

U (k)---the sampled value that voltage regulation is k time;

I (k)---the sampled value that electric current is the k time;

Sampling number in mono-cycle of N-------;

Described active-power P, reactive power Q, discrete formula

Single-phase active power and reactive power are defined as:

$P=\frac{1}{T}{\∫}_0^{T}p\left(t\right)\mathrm{dt}=\frac{1}{T}{\∫}_0^{T}u\left(t\right)i\left(t\right)\mathrm{dt}---(0-5)$

$Q=\frac{1}{T}{\∫}_0^{T}q\left(t\right)\mathrm{dt}=\frac{1}{T}{\∫}_0^{T}u(t-\frac{T}{4})i\left(t\right)\mathrm{dt}---(0-6)$

Discretization obtains later:

$P=\frac{1}{N}\underset{k=1}{\overset{N}{\mathrm{\Σ}}}u\left(k\right)i\left(k\right)---(0-7)$

$Q=\frac{1}{N}\underset{k=1}{\overset{N}{\mathrm{\Σ}}}u(k-\frac{N}{4})i\left(k\right)---(0-8)$

The calculating of described apparent power

Single-phase apparent power is:

$S=U\&times;I=\sqrt{{\mathrm{<figure-callout\; id="2"\; label="P"\; filenames="DEST\_PATH\_HDA00001721078800011.png,DEST\_PATH\_HDA00001721078800032.png"\; state="\{\{state\}\}">P</figure-callout>}}^2+Q^2}---(0-9)$

Described power factor

calculating

The relation of single-phase active power, reactive power and multiple merit power is as follows:

S＝P+jQ (0-10)

By formula (4-10), can try to achieve power factor is:

Due to power-factor angle

so can be calculated by following formula:

The judgement of load characteristic

When Q > 0,

load is perception; When Q < 0,

load is capacitive;

The described closed loop control algorithm based on DSP is, by touch-screen, selects different control models, and described different control model comprises, voltage adjustment and power factor adjustment.Voltage is adjusted control model and be take line voltage as controlled quentity controlled variable, by different reactive currents is provided, by the voltage stabilization of electrical network on given operating voltage point; Power factor is adjusted control model, and to take the power factor of electrical network be controlled quentity controlled variable, by different reactive currents is provided, the power factor of electrical network is stabilized on the power factor point of setting;

Internal processes obtains selected control model by judgement, if take voltage as controlling target, just by given voltage-regulation desired value, introduces voltage negative feedback, by the phase line voltage U and the given reference voltage U that detect _refcompare, its deviation is input to PI governing loop; Pi regulator calculates the phase-shift control angle that export, controls the reactive power output size of MCR by phase-shift trigger circuit, changes line voltage;

Equally, if take power factor as controlling target, just by given power factor regulation desired value, introduce voltage and current feedback, calculate power factor of electric network as negative feedback; Line voltage u and power network current i by detecting, then calculate power-factor angle

with given reference voltage

compare, its deviation is input to PI governing loop, and pi regulator calculates the phase-shift control angle that export, controls the reactive power output size of MCR by phase-shift trigger circuit, changes power factor of electric network, after two kinds of situation discretizations, on DSP, realizes;

The performing step of described phase-shift trigger circuit: in DSP, filtered synchronizing signal is outputed to its inner triggering signal generative circuit; Triggering signal generative circuit is also accepted the signal from ARM data receiver circuit, described data receiver circuit is the self-defined parallel bus of a 4bit, data receiver circuit receives the control signal of being sent by bidirectional RAM by ARM, and each phase Trigger Angle signal receiving is exported to triggering signal generative circuit; By triggering signal generative circuit, generate and specify the burst signal of the angle of flow to remove to control MCR; Described triggering signal generative circuit is: sinusoidal signal obtains synchronizing signal by zero passage comparison circuit, and synchronizing signal is input to DSP, by being sent to circuits for triggering generative circuit after DSP digital filtering.By obtaining counter equivalence waveform after integration counter, then the given angle of flow obtaining according to DSP, counter equivalence waveform is carried out to PWM conversion and obtain homophase carrier signal, after described homophase carrier signal output DSP, drive the upper corresponding thyristor of MCR.

Described ARM is provided with man-machine interaction program, and it comprises and is divided into three parts: keyboard decoding circuit program, Keyboard Control program, display routine;

Described keyboard decoding circuit program is: in ARM inside, MCR controller has been designed altogether to 15 function buttons and a reset key, 15 function buttons are become to 4bit data and be input to bidirectional RAM, the prerequisite of decoding is that hypothesis user only carries out the operation of a button at synchronization, if supress a plurality of keys simultaneously, with keypad priority, determine button;

Keyboard Control program is a critical function of man-machine interaction, and user can carry out Picture switch, parameter input, control command input operation by keyboard.

Described display routine comprises LCD initialization function and interface display function.Thus, having reached the magnetic valve type controllable reactor real-time working information that user is needed is shown in liquid crystal display.

The technology of the present invention main points

(1) controller hardware framework: hardware platform adopts multiprocessor Collaborative Control pattern-DSP+ARM framework, the last word TMS320F28335 of dsp chip WeiTI company, it is mainly responsible for the computing of Digital Signal Processing and core algorithm.ARM chip is 16/32 RISC (reduced instruction set computer) microprocessor S3C2410A based on ARM920T core of Samsung company, is mainly responsible for processing and the HMI (human-computer interaction function) of peripheral signal.Between two kinds of control chips, by dual port RAM, realize data sharing.Extend out at a high speed simultaneously, high accuracy 16 potential differences divide AD to realize quick undistorted sampling, meet well the requirement of industry spot speed and precision.

(2) controller software is realized: on software, adopted hierarchical control, modular thought, made every effort to realize and control succinct reliable, software and can assemble, maintenance upgrade is object easily.

First be the realization (core layer) of hierarchical control: the DSP functions such as realization, data storage and exchange of being responsible for quick high accuracy sampling, core algorithm; ARM be responsible for the control of liquid crystal display, the response of touch screen soft-keyboard and with the communication function (Communication Layer) of Monitor Computer Control System.

Next is the thought that has adopted modularization programming, DSP program and ARM program, strictly according to modular Programming principle, have been carried out careful functions of modules and have been cut apart and realize, and make whole program possess higher modularization level, better readable, later maintenance upgrading easily.

Major control process prescription is as follows:

DSP obtains current system state by AC sampling or instantaneous reactive Sampling techniques, and each quantity of state obtaining is realized data sharing by dual port RAM and ARM;

By control program and each defence program, calculate the current pilot angle of system;

The pilot angle obtaining is used for controlling magnet controlled reactor by signal of telecommunication pulse;

ARM be responsible for showing and the processing of touch screen operation and with the communication of Monitor Computer Control System.

During the design of system hardware schematic diagram, increase surge protection and electrostatic protection function; During PCB layout drawing, by each functional module, divide meticulously, take into full account EMC characteristic, realized high/low volt circuit separated, the separation of analog/digital circuit, the separation of low speed/high speed circuit; During Software for Design, according to soft project design philosophy from top to bottom, for various functions, divide module, modules cohesion is strong, the degree of coupling is low, easy upgrade maintenance.

Controller architecture, in strict accordance with < < IEC 60297-3-101-2004Mechanical structures for electronic equipment-Dimensions of mechanical structures of the 482,6mm (19in) series-Part 3-101:Subracks and associated plug-in units > > standard designs.Internal circuit board carries out Module Division by function and principle of EMC, and the size of each module designs in strict accordance with standard.Controller is divided into by each functional module: power module, analog module, digital quantity input module, digital output module, signal of telecommunication output unit, bus module etc.After dividing module by function, controller has the plurality of advantages such as strong interference immunity, easily debugging, easy care.

The operation principle of magnetic valve type controllable reactor

By embedded controller to magnet controlled reactor (Magnetic valve Controllable Reactor, the Trigger Angle of thyristor MCR) is controlled, by the excitatory magnetic saturation that changes iron core of control loop DC control electric current, thereby reach the calutron that its reactive capability of smooth adjustment is exported.MCR has polytype, and what wherein have development potentiality is magnetic valve type and two kinds of structures of iron core split type.MCR is the important device of voltage control and reactive power compensation in electric power system, is being subject to having paid attention to widely and having obtained preliminary application in recent years.Compare with existing other reactive power compensator, MCR has that applicable voltage range is wide, reactive capability is large, reliability is high, harmonic wave is little, cost is low, safeguard the advantages such as simple, is applicable to large-scale promotion and uses.

In the actual motion of MCR, need to communicate by letter and realize remote monitoring with comprehensive automation system of transformer substation.Comprehensive automation system of transformer substation generally adopts serial communication or network mode.Also controller module communication interface can be passed through, remote monitoring can be realized.

Beneficial effect of the present invention:

1) the idle and voltage parameter of detection of grid quick and precisely;

2) can automatically detect and adapt to substation operation state (apportion, off-the-line side by side);

3) can take corresponding control strategy according to controlling target (idle or voltage), accurately control;

4) the electric network reactive-load situation record of certain hour can be stored, user can read these data by serial communication mode;

5) can realize controller Long-distance Control controlled reactor, realize the separated installation of body and controller;

6) man-machine interface is friendly;

7) can meet on-the-spot EMC Requirements;

8) magnetic valve type controllable reactor manufacturing process is simple, and cost is low, and loss is little, and harmonic wave is little, and the voltage scope of application is wide, for the ability to transmit electricity, adjustment line voltage, compensating power and the over-voltage that improve electrical network, all has larger application potential.

Accompanying drawing explanation

Fig. 1 is magnet controlled reactor controller principle figure;

The magnetic circuit schematic diagram of Fig. 2 A magnetic valve type controllable reactor;

Fig. 2 B magnetic circuit equivalent schematic;

Fig. 3 is DSP principle of phase lock loop block diagram;

Fig. 4 is MCR voltage mode control schematic diagram;

Fig. 5 is MCR power factor controlling pattern diagram;

Fig. 6 is triggering signal generative circuit principle;

Fig. 7 A is the flow chart of interrupt service routine;

Fig. 7 B is the flow chart of interrupt service routine;

Fig. 8 is the flow chart of control system control method.

Wherein 1. analog modules, 2. host computer, 3. signal of telecommunication output unit, 4. status indicator lamp, 5. controller module, 6. power supply processing module, 7. clock chip, 8. nonvolatile memory.

Embodiment

Below in conjunction with accompanying drawing and embodiment, the invention will be further described.

In Fig. 1, a kind of magnet controlled reactor controller, it comprises controller module 5, controller module 5 is connected respectively with signal of telecommunication output unit 3 with analog module 1; Described controller module 5 is gone back and upper machine communication, and described controller module 5, signal of telecommunication output unit 3 are connected with power supply processing module 6 respectively; Signal of telecommunication output unit 3 is connected with reactor.

Controller module 5 is DSP+ARM framework, and described DSP is connected with power supply processing module 6 respectively with ARM; DSP is connected by dual port RAM with ARM; Analog module 1 comprises AD chip, described DSP input is connected with AD chip, DSP output is connected with signal of telecommunication output unit, and described DSP is also connected with nonvolatile memory 8 with clock chip 7, and the ARM in described controller module 5 and host computer 2 are by serial or network interface communication.

Signal of telecommunication output unit 3 is connected with power supply processing module 6; Described signal of telecommunication output unit 1 is connected with the pulse transformer in magnet controlled reactor.DSP is connected with status indicator lamp 4.Dsp chip is TMS320F28335; ARM chip S3C2410A.The PT that AD chip is provided with external electrical network is connected with CT.

Pulse-triggered shielded type cable, is convenient to outdoor wiring, and controller is portable construction, insertion box-type design, and dustproof, waterproof, shockproof, be applicable to outdoor use,

Power supply processing module is that ac-dc conversion device is AC/DC modular power source.Power supply processing module 6 provides working power for dsp chip and ARM core and dual port RAM.

The electric current time variant voltage that PT or CT connect is successively that I/V circuit, low-pass filter circuit, double-click turn single-level circuit, output protection circuit; described PT or CT comprise the PT being connected with main transformer, CT, the standby PT connecting, the standby CT connecting that becomes of becoming, i.e. main transformer PT, CT and standby PT, the CT of becoming that main transformer connects.

Described outside extension storage device is EEPROM; Described clock signal device comprises the calendar clock chip of expansion, and described calendar clock is DS1302, and described calendar clock chip is provided with crystal oscillator, and described crystal oscillator frequency is 30MHZ; Described display unit is LCD display, and LCD display is touch-screen; Or utilize controller module 5 communication interfaces to connect human-computer interaction device, as keyboard, described keyboard comprises 15 function keys and a reset key, described 15 function keys comprise rise, move, stop, communication, downward, determine, cancel, check, automatically, manually, arrange, to time and upper and lower, left and right options button; Described keyboard is Low level effective type, and the time constant of described reset key is greater than other keys; Described dsp processor also connects JTAG chip internal test interface.

Fig. 2 A is magnetic valve type controllable reactor magnetic circuit schematic diagram, by the large part of Area comparison (area is Ab, and length is l, is called " large area core packet " below) and the little part of Area comparison, (area is Ab1 to iron core, length is lt, is called " magnet valve core packet " below) be in series.

Within the scope of the whole capacity regulating of magnetic valve type controllable reactor, the operating state of large area core packet is the unsaturation linear zone in magnetic circuit all the time, and its magnetic resistance is very little with respect to magnet valve core packet, can ignore.The magnet valve part magnetic line of force is divided into two parts, and a part is by magnet valve iron core, and magnetic resistance is designated as Rt, and another part is by air gap, and equivalent magnetic resistance is designated as Rq

Fig. 2 B magnetic valve type controllable reactor magnetic circuit can equivalent schematic.In figure, F is magnetic circuit magnetic potential, and Φ is magnetic circuit total magnetic flux,

(μ ₀for air permeability), (μ is the average magnetic permeability of magnet valve iron core).

Fig. 3, Fig. 4, Fig. 5, Fig. 6, Fig. 7 A, Fig. 7 B, Fig. 8 magnet controlled reactor controller control method, it comprises the steps:

1) voltage sensor, the current sensor of DSP by electrical network carries out AC sampling and obtains current system state; Described voltage sensor, current sensor carry out line voltage and line current collection to power network line, adopt two kinds of digital filter series connection associating filtering modes of comparison expression digital filter and integration type digital filter in described AC sampling in DSP; Subsequently to filtered line voltage and line current carry out digital phase-locked frequency multiplier sampling, by AD, change interrupt service routine the line voltage effective value of electrical network, line current effective value, active power, reactive power, apparent power, each quantity of state of power factor calculated;

2) by the touch screen operation being connected with ARM, select voltage adjustment or power factor to adjust one of two kinds of control models; The line voltage gathering or line current sinusoidal signal obtain synchronizing signal by crossing zero balancing, using zero crossing synchronizing signal as phase shift benchmark; DSP calculates the phase shifting angle that the every phase of current time should be exported; Described control program comprises the closed loop control algorithm based on DSP;

3) DSP according to the phase shift angle of calculating in conjunction with phase shift benchmark, and the magnetic valve type controllable reactor that will control is specially single-phase or three-phase, single-phase or the three-phase triggering signal triggering signal of corresponding generation, utilize signal of telecommunication pulsed drive pulse transformer wherein to control magnetic valve type controllable reactor, pulse transformer sends pulse train and ensures that the upper corresponding thyristor of magnetic valve type controllable reactor MCR excites reliably;

Described digital phase-locked frequency multiplier sampling comprises:

I), DSP has trapping module CAP to obtain current demand signal frequency, the magnetic valve type controllable reactor of controlling is as required specially single-phase or three relative trapping module CAP and accepts or rejects use; Described power system frequency is the inverse of time difference of twice positive going zeror crossing point of institute's survey line voltage; The synchronizing signal of any phase line voltage is input on CAP1 input port, by software, configures, and the hardware of CAP1 catches the time of adjacent twice saltus step, i.e. cycle T; Thereby frequency is asked as f=1/T, the grid line voltage signal frequency using it as first-harmonic; By line voltage signal frequency, the line current frequency of same phase obtains simultaneously;

Ii), the grid line voltage as first-harmonic that sample frequency is set as collecting or line current signal frequency 128 times, the high order harmonic component of need analyzing is 32 times, therefore low pass filter elects 50 * 32=3.2kHz as by frequency, 32 above high order harmonic components of elimination, prevent the aliasing of sampling effectively;

Iii), described digital phase-locked frequency multiplier is to be realized by dsp program, because digital circuit can realize precise synchronization output, so omit feedback element, adopts open-loop design principle; This digital phase-locked frequency multiplier is also referred to as homophase frequency multiplication;

The ADSOC that is input to AD module when synchronizing frequency doubling signal controls on mouth; By software, arrange, make an AD conversion of synchronizing frequency doubling signal rising edge triggering each time, after AD EOC, automatically trigger AD interrupt service routine; The result that in interrupt service routine, storage is sampled each time, then an AC sampling calculating is carried out in every 128 samplings after finishing, by the discrete formula of each physical quantity, calculate line voltage, line current, active power, reactive power, apparent power, the power factor value of electrical network, by dual port RAM and ARM, realize data sharing, as the input variable of controlling and showing;

Described closed loop control algorithm: controller has been taked two kinds of control strategies: user, according to actual conditions, selects different control models by touch screen operation; Voltage adjusts control model and power factor is adjusted control model; Voltage is adjusted control model and be take line voltage as controlled quentity controlled variable, by different reactive currents is provided, by the voltage stabilization of electrical network on given operating voltage point; Power factor is adjusted control model, and to take the power factor of electrical network be controlled quentity controlled variable, by different reactive currents is provided, the power factor of electrical network is stabilized on the power factor point of setting; According to control principle, if take voltage as controlling target, given voltage-regulation desired value, introduces voltage negative feedback; By the line voltage U and the given reference voltage U that detect _refcompare, its deviation is input to PI governing loop, and pi regulator calculates the phase-shift control angle of output, controls the reactive power output size of MCR by circuits for triggering, changes line voltage;

Equally, if will adjust control model with power factor, given power factor regulation desired value, introduces voltage and current feedback, calculates power factor of electric network as negative feedback; Line voltage u and power network current i by detecting, then calculate power-factor angle with given reference voltage

compare, its deviation is input to PI governing loop; Pi regulator calculates the phase-shift control angle that export, controls the reactive power output size of MCR by circuits for triggering, changes power factor of electric network;

After two kinds of algorithm discretizations, on DSP, realize; The responsive time constant of the time constant of pi regulator and MCR itself adapts;

The line voltage gathering or line current sinusoidal signal obtain synchronizing signal by crossing zero balancing, using zero crossing synchronizing signal as phase shift benchmark, DSP calculates the phase shift angle that the every phase of current time should be exported, DSP is according to phase shift angle and the phase shift benchmark received, produce triggering signal, for the reliable thyristor that triggers, for pulse transformer, adopt trigger impulse is carried out to the method triggering that software homophase carrier wave is subdivided into a plurality of pulse trains.

Under certain conditions, as the application of reactor at (40HZ-60HZ) of power frequency 50HZ left and right, also can take directly to gather line voltage and line current signal in power network line, by DSP, control in real time, phase-shift control angle is provided, meets the needs that improve line voltage and improve power factor of electric network.

Utilize dsp program to realize filter circuit; System has been used two kinds of filters: two kinds of filter series connection of comparison expression filter and integration type filter; Integration type filter is realized the low-pass filtering of digital signal, the effectively shake of the signal of filtering and burr, and filtering cut-off frequency is adjustable on a large scale, comparison expression filter is applicable to the higher situation of cut-off frequency, and the two is in conjunction with the input processing strengthening signal of interest;

Take sampling thheorem theory as basis, requiring sample frequency is the more than 2 times of highest frequency in measured signal frequency spectrum, adopt hardware synchronization sampling method to measured signal, be that synchronized sampling method is exactly the complete cycle of uniform sampling uniformly-spaced, between sampling number N, meet relational expression T=N Δ t in measured signal cycle T, sampling time interval Δ t and a cycle, that is: sample frequency be measured signal frequency N doubly.

Grid frequency measurement circuit measuring goes out current demand signal frequency, DSP calculates the frequency multiplication cycle by 128 frequencies, the synchronizing frequency doubling signal of generation and input signal homophase, has so just realized the homophase of supplied with digital signal times frequency sampling, and the ADSOC that sampled signal is input to DSP triggers AD interruption;

Described grid frequency measurement circuit is to utilize DSP trapping module CAP that the synchronous signal acquisition of line voltage is configured by software, and CAP can catch the time of adjacent twice saltus step, i.e. cycle T; Power system frequency is exactly the inverse of time difference of twice positive going zeror crossing point of surveyed phase voltage; This time difference is the cycle of alternating voltage amount namely; Thereby frequency can be asked as f=1/T.

It is mouthful upper that the ADSOC that synchronizing frequency doubling signal is input to DSP controls, and by software, arranges, make synchronizing frequency doubling signal each time rising edge trigger an AD conversion, after AD EOC, automatically trigger AD interrupt service routine;

The result that in described AD interrupt service routine, storage is sampled each time, then an AC sampling calculating and the closed loop control algorithm based on DSP are carried out in every 128 samplings after finishing, simultaneously by counter O reset, wait for the circulation after 128 samplings of next round finish, for sampling, to alternating voltage U, electric current I, active-power P, reactive power Q, power factor

discretization is carried out in the synchronous AC sampling of apparent power electric parameter, calculate voltage, electric current, active power, apparent power, reactive power, the power factor of electrical network, described AC sampling is calculated as the discrete formula by each physical quantity, calculate voltage, electric current, active power, reactive power, apparent power, the power factor value of electrical network, as the input variable of controlling and showing;

Alternating voltage U, electric current I discrete formula

Current effective value, voltage effective value, be defined as:

$U=\sqrt{\frac{1}{T}{\&Integral;}_0^T{u}^2\left(t\right)\mathrm{dt}}---(0-13)$

$I=\sqrt{\frac{1}{T}{\&Integral;}_0^T{i}^2\left(t\right)\mathrm{dt}}---(0-14)$

In formula:

T---be the sampling period;

U (t)---instantaneous voltage;

I (t)---current instantaneous value.

By after above two formula discretizations:

$U=\sqrt{\frac{1}{N}\underset{k=0}{\overset{N-1}{\mathrm{\&Sigma;}}}u{\left(k\right)}^2}---(0-15)$

$I=\sqrt{\frac{1}{N}\underset{k=0}{\overset{N-1}{\mathrm{\&Sigma;}}}i{\left(k\right)}^2}---(0-16)$

In formula:

U (k)---the sampled value that voltage regulation is k time;

I (k)---the sampled value that electric current is the k time;

Sampling number in mono-cycle of N-------;

Described active-power P, reactive power Q, discrete formula

Single-phase active power and reactive power are defined as:

$P=\frac{1}{T}{\&Integral;}_0^{T}p\left(t\right)\mathrm{dt}=\frac{1}{T}{\&Integral;}_0^{T}u\left(t\right)i\left(t\right)\mathrm{dt}---(0-17)$

$Q=\frac{1}{T}{\&Integral;}_0^{T}q\left(t\right)\mathrm{dt}=\frac{1}{T}{\&Integral;}_0^{T}u(t-\frac{T}{4})i\left(t\right)\mathrm{dt}---(0-18)$

Discretization obtains later:

$P=\frac{1}{N}\underset{k=1}{\overset{N}{\mathrm{\&Sigma;}}}u\left(k\right)i\left(k\right)---(0-19)$

$Q=\frac{1}{N}\underset{k=1}{\overset{N}{\mathrm{\&Sigma;}}}u(k-\frac{N}{4})i\left(k\right)---(0-20)$

The calculating of described apparent power

Single-phase apparent power is:

$S=U\&times;I=\sqrt{{\mathrm{<figure-callout\; id="2"\; label="P"\; filenames="DEST\_PATH\_HDA00001721078800011.png,DEST\_PATH\_HDA00001721078800032.png"\; state="\{\{state\}\}">P</figure-callout>}}^2+Q^2}---(0-21)$

Described power factor

calculating

The relation of single-phase active power, reactive power and multiple merit power is as follows:

S＝P+jQ (0-22)

By formula, can try to achieve power factor is:

Due to power-factor angle so can be calculated by following formula:

The judgement of load characteristic

When Q > 0,

load is perception; When Q < 0,

load is capacitive;

The described closed loop control algorithm based on DSP is, by touch-screen, selects different control models, and described different control model comprises, voltage adjustment and power factor adjustment.Voltage is adjusted control model and be take line voltage as controlled quentity controlled variable, by different reactive currents is provided, by the voltage stabilization of electrical network on given operating voltage point; Power factor is adjusted control model, and to take the power factor of electrical network be controlled quentity controlled variable, by different reactive currents is provided, the power factor of electrical network is stabilized on the power factor point of setting;

Internal processes obtains selected control model by judgement, if take voltage as controlling target, just by given voltage-regulation desired value, introduces voltage negative feedback, by the phase line voltage U and the given reference voltage U that detect _refcompare, its deviation is input to PI governing loop; Pi regulator calculates the phase-shift control angle that export, controls the reactive power output size of MCR by phase-shift trigger circuit, changes line voltage;

Equally, if take power factor as controlling target, just by given power factor regulation desired value, introduce voltage and current feedback, calculate power factor of electric network as negative feedback; Line voltage u and power network current i by detecting, then calculate power-factor angle

with given reference voltage

compare, its deviation is input to PI governing loop, and pi regulator calculates the phase-shift control angle that export, controls the reactive power output size of MCR by phase-shift trigger circuit, changes power factor of electric network, after two kinds of situation discretizations, on DSP, realizes;

Described ARM is provided with man-machine interaction program, and it comprises and is divided into three parts: keyboard decoding circuit program, Keyboard Control program, display routine;

Described keyboard decoding circuit program is: in ARM inside, MCR controller has been designed altogether to 15 function buttons and a reset key, 15 function buttons are become to 4bit data and be input to bidirectional RAM, the prerequisite of decoding is that hypothesis user only carries out the operation of a button at synchronization, if supress a plurality of keys simultaneously, with keypad priority, determine button;

Keyboard Control program is a critical function of man-machine interaction, and user can carry out Picture switch, parameter input, control command input operation by keyboard.

Described display routine comprises LCD initialization function and interface display function.Thus, having reached the magnetic valve type controllable reactor real-time working information that user is needed is shown in liquid crystal display.

Although above-mentioned, by reference to the accompanying drawings the specific embodiment of the present invention is described; but be not limiting the scope of the invention; one of ordinary skill in the art should be understood that; on the basis of technical scheme of the present invention, those skilled in the art do not need to pay various modifications that creative work can make or distortion still in protection scope of the present invention.

Claims (1)

1. the control method of a magnet controlled reactor controller, it is characterized in that, described magnet controlled reactor controller comprises controller module (5), described controller module (5) is DSP+ARM framework, described DSP is connected by dual port RAM with ARM, and controller module (5) is connected respectively with signal of telecommunication output unit (3) with analog module (1); Described analog module (1) comprises AD chip, the voltage collecting device that described AD chip is provided with external electrical network is connected, described controller module (5) also with host computer (2) communication, described controller module (5), signal of telecommunication output unit (3) are connected with power supply processing module (6) respectively; Described signal of telecommunication output unit (3) is connected with the pulse transformer in magnet controlled reactor;

Described control method comprises the steps

1) voltage sensor, the current sensor of DSP by electrical network carries out AC sampling and obtains current system state; Described voltage sensor, current sensor carry out line voltage and line current collection to power network line, adopt two kinds of digital filter series connection associating filtering modes of comparison expression digital filter and integration type digital filter in described AC sampling in DSP; Subsequently to filtered line voltage and line current carry out digital phase-locked frequency multiplier sampling, by AD, change interrupt service routine the line voltage effective value of electrical network, line current effective value, active power, reactive power, apparent power, each quantity of state of power factor calculated;

2) by the touch screen operation being connected with ARM, select voltage adjustment or power factor to adjust one of two kinds of control models; The line voltage gathering or line current sinusoidal signal obtain synchronizing signal by crossing zero balancing, using zero crossing synchronizing signal as phase shift benchmark; DSP calculates the phase shifting angle that the every phase of current time should be exported; Control program comprises the closed loop control algorithm based on DSP;

3) DSP according to the phase shift angle of calculating in conjunction with phase shift benchmark, and the magnetic valve type controllable reactor that will control is specially single-phase or three-phase, single-phase or the three-phase triggering signal triggering signal of corresponding generation, utilize signal of telecommunication pulsed drive pulse transformer wherein to control magnetic valve type controllable reactor, pulse transformer sends pulse train and ensures that the upper corresponding thyristor of magnetic valve type controllable reactor MCR excites reliably;

Described digital phase-locked frequency multiplier sampling comprises:

I), DSP has trapping module CAP to obtain current demand signal frequency, the magnetic valve type controllable reactor of controlling is as required specially single-phase or three relative trapping module CAP and accepts or rejects use; Power system frequency is the inverse of time difference of twice positive going zeror crossing point of institute's survey line voltage; The synchronizing signal of any phase line voltage is input on CAP1 input port, by software, configures, and the hardware of CAP1 catches the time of adjacent twice saltus step, i.e. cycle T; Thereby frequency ask into: f=1/ t, the grid line voltage signal frequency using it as first-harmonic; By line voltage signal frequency, the line current frequency of same phase obtains simultaneously;

Ii), the grid line voltage as first-harmonic that sample frequency is set as collecting or line current signal frequency 128 times, the high order harmonic component of need analyzing is 32 times, therefore low pass filter elects 50 * 32=3.2kHz as by frequency, 32 above high order harmonic components of elimination, prevent the aliasing of sampling effectively;

Iii), described digital phase-locked frequency multiplier is to be realized by dsp program, because digital circuit can realize precise synchronization output, so omit feedback element, adopts open-loop design principle; This digital phase-locked frequency multiplier is also referred to as homophase frequency multiplication;

The ADSOC that is input to AD module when synchronizing frequency doubling signal controls on mouth; By software, arrange, make an AD conversion of synchronizing frequency doubling signal rising edge triggering each time, after AD EOC, automatically trigger AD interrupt service routine; The result that in interrupt service routine, storage is sampled each time, then an AC sampling calculating is carried out in every 128 samplings after finishing, by the discrete formula of each physical quantity, calculate line voltage, line current, active power, reactive power, apparent power, the power factor value of electrical network, by dual port RAM and ARM, realize data sharing, as the input variable of controlling and showing;

Described closed loop control algorithm: controller has been taked two kinds of control strategies: user, according to actual conditions, selects different control models by touch screen operation; Voltage adjusts control model and power factor is adjusted control model; Voltage is adjusted control model and be take line voltage as controlled quentity controlled variable, by different reactive currents is provided, by the voltage stabilization of electrical network on given operating voltage point; Power factor is adjusted control model, and to take the power factor of electrical network be controlled quentity controlled variable, by different reactive currents is provided, the power factor point that the power factor of electrical network is stabilized in to setting is upper: according to control principle, if take voltage as controlling target, given voltage-regulation desired value, introduces voltage negative feedback; By line voltage U and the given la tension de reference Uref est detecting, compare, its deviation is input to PI governing loop, and pi regulator calculates the phase-shift control angle of output, controls the reactive power output size of MCR by circuits for triggering, changes line voltage;

Equally, if will adjust control model with power factor, given power factor regulation desired value, introduces voltage and current feedback, calculates power factor of electric network as negative feedback; Line voltage u and power network current i by detecting, then calculate power-factor angle φ, and in given reference voltage φ _refcompare, its deviation is input to PI governing loop; Pi regulator calculates the phase-shift control angle that export, controls the reactive power output size of MCR by circuits for triggering, changes power factor of electric network;

After two kinds of algorithm discretizations, on DSP, realize; The responsive time constant of the time constant of pi regulator and MCR itself adapts;

The line voltage gathering or line current sinusoidal signal obtain synchronizing signal by crossing zero balancing, using zero crossing synchronizing signal as phase shift benchmark, DSP calculates the phase shift angle that the every phase of current time should be exported, DSP is according to phase shift angle and the phase shift benchmark received, produce triggering signal, for the reliable thyristor that triggers, for pulse transformer, adopt trigger impulse is carried out to the method triggering that software homophase carrier wave is subdivided into a plurality of pulse trains.

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