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, and " transferring electricity from the west to the east, north and south supplies mutually " is the fundamental state policy [5] of China's 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 big electrical network; How electric energy is transported to the load center that distribution system belongs to safely and efficiently from the power plant; How high-quality electric energy is provided for the user; How to effectively reduce idle pollution, guarantee that the safe and highly efficient operation of electrical network becomes one of of paramount importance research topic in electrical engineering field electrical network.
Have a large amount of asynchronous motors, transformer, power electronic equipment in the electrical network, these equipment will consume a large amount of reactive powers.If these reactive powers can not be compensated in time, can be to efficient, safety, stable the having a negative impact of electrical network.So producing, the research and development of reactive power compensation Study on Theory and high-performance reactive-load compensation equipment just put on schedule.
The theory of reactive power compensation relates to the aspects from system and user, and especially relevant with quality of power supply problem is because most power quality problem can be eased or thoroughly solution through reactive power is suitably controlled.Usually, the problem of reactive power compensation can be considered from two aspects: load compensation and voltage support.The purpose of load compensation will improve the system power factor exactly, thus the active power that the symmetrical alternating current electric power system produces, and eliminate the harmonic wave that high-power variation nonlinear-load produces.The target that voltage supports is exactly the voltage fluctuation that will reduce transmission line ends.The reactive power compensation of transmission system is to improve AC system stability through the maximum transmitted ability that improves active power, and helps keeping the voltage of electric power systems at different levels stable.It can improve high voltage direct current transmission conversion terminal capabilities, improves efficiency of transmission, and control stable state and temporary overvoltage are avoided system crash.
Series connection and parallelly connected reactive power compensation are 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 the 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
Early stage in reactive power compensation development, synchronous compensator have been played the part of a dominant role at voltage aspect the stable and idle control.From the principle angle, synchronous compensator is exactly the synchronous machine that links to each other with electric power system.After the compensator operation, can produce or absorb the reactive power that alternating current circuit needs.Through suitable automatic magnetic exciting circuit, the phase modulation function provides continuous reactive power.Synchronous compensator is a purpose to improve the stability of a system usually, is used in compartment system and transmission line, and under the situation of load variations, sustaining voltage changes in allowed limits.Yet; Synchronous compensator takies bigger 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 SVC, and its advantage only is the high overload ability that has in short-term, seldom use now.
Used shunt capacitor to improve power factor of electric network in 1914 first, shunt capacitor generation leading current compensates the lagging current of load generating.The factor that the selection of shunt capacitor need be considered is more, and what wherein need the emphasis consideration is the idle size of hysteresis of load generating.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 the reactive power compensation amount through the switch on-off capacitor, drop into or excise the capacitor group according to total reactive requirement.The smoothness of control 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 bigger impulse current simultaneously, need often to safeguard.
SVC (Static Var Compensator-SVC) is the one type of fast reactive adjusting device that grows up the external seventies, successfully is applied in the compensation of loads such as electric railway, metallurgy, electric power, mining and high energy acclerator.This type device has remarkable advantages at the aspects such as economy of reliability, investment and the operating cost of the rapidity of regulating, function diversity, work than synchronous compensator; Can obtain technical economic benefit preferably, thereby obtain development faster at home and abroad.
The SVC of main flow mainly contains three types: 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).
Though TSC can only the grouping switching capacitor, can not regulate reactive power continuously, control is simple, and cost is lower, and does not have harmonic current, and the low-voltage load end that is adapted at electrical network disperses reactive power compensation.
TCR can the smooth adjustment capacity and response speed very fast, (obtained extensive application in 6~35KV) the reactive power compensation at the medium voltage electricity circuit.But TCR triggers the phase angle through the control thyristor to come directly control reactor output current; The output current distortion is very serious, and the waveform indention is a very big harmonic source; Must move simultaneously with filtering capacitor group (Filter Capacitor is called for short FC).A large amount of uses of TCR can cause the decline significantly of the quality of power supply, and bring new threat for the safe operation of electrical network.In addition, thyristor and reactor are under the same voltage in the TCR system, have limited its application on 110kV and above electric pressure electrical network.
MCR is by the magnetic saturation of the excitatory change iron core of control loop DC control electric current (being the working point), thereby reaches the purpose of the idle output of smooth adjustment.The version of MCR has a variety of, and characteristic difference is also bigger.In recent years research shows, it is two kinds of magnetic valve type and iron core split types that application prospect MCR type is arranged most.Compare with TCR, the voltage that the control thyristor of MCR is born has only about 2% of rated voltage, and its electric current is also only required specified Control 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 that brings.And the harmonic performance of MCR output current is better than TCR, helps the safe and highly efficient operation of electrical network.The manufacturing of MCR is simple, and the design of magnet valve makes that the efficient of MCR has obtained significantly improving in addition, and noise reduces significantly.Consider that from economy MCR is simple in structure, low price, floor space is little.Based on above-mentioned various advantages, the trend of using MCR to substitute TCR is arranged all 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 keep its voltage than the capacitor of low capacity at its DC side and get final product [30].SVG can make it send reactive power through suitable control, is capacitive character, also can make its absorbing reactive power, is inductive.SVG is a kind of advanced person's a modern compensation arrangement, if adopt multipleization or PWM control technology, can make its output current harmonics composition less and be applied to the high voltage appearance grade, and shortcoming is can only the compensating reactive power electric current, can not the compensation harmonic electric current.
Active Power Filter-APF (Active Power Filter is called for short APF) is a kind of novel electric power electric device that is used for dynamically suppressing harmonic wave, compensating reactive power.It can compensate frequency and the harmonic wave that all changes of size and the reactive power of variation, and the variation of target compensation is had the response speed that is exceedingly fast.For APF, what need solution at present is the production domesticization of (1) core devices; (2) reduce cost; (3) solve the high-voltage applications integrity problem.If these problems are well solved, APF will become one of optimal selection that improves power grid quality.
SVC uses the reactive-load compensation equipment [31-33] the most extensive, that technology is the most ripe in the current various reactive-load compensation equipment.Based on the reactive power compensation technology (SVG, APF) of full control device have that the device core technology is high by foreign corporation's monopolization, cost, the technological shortcoming such as not mature enough of high-voltage applications, in a period of time from now on, can't replace SVC in the mesohigh field.
In at present main three kinds of SVC (TCR, MCR and TSC), MCR has the advantage of tangible technology and price in mesohigh reactive power compensation field, is fit to large-scale promotion and uses.The high performance of control device can make the performance of MCR be greatly enhanced, and this makes the high-performance MCR controller that designs and develop the suitable commercial Application of a cover become a very significant job.
1.2 research trends and existing problems
MCR is the operating experience in existing more than 20 year abroad, has the MCR of the 35~500kV of cover more than 50 electric pressure in the engineering of Russia, member country of the Commonwealth of Independent States and Brazil, to use.Russia had developed 500kV, 180Mvar three-phase magnet controlled reactor [34-37] in 2005.Owing to recognize the advantage of MCR in the high-power field, European many countries also begin MCR is carried out deep research.
At home, 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 in a plurality of electric railways Traction Station, put into operation in early 1990s.Colleges and universities have also launched the research of this respect, and have obtained bigger progress.Manufacturer studies 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 the exploitation and the application study of 110 kilovolts of controlled reactors.In April, 2007, to develop 110 kilovolts of MCR of domestic first platform, and passed through delivery test and relevant type approval test, in June, the completion Installation and Debugging also put into operation successfully.The MCR model machine (iron core split type) of 500kV three-phase 40Mvar by development in 2006 is through shop test, transports in April, 2007 on-the-spot and trys out.
At present, the MCR controller that most domestic producer researchs and produces mostly is to be core with 80C196, and it is slow to exist control rate, and sampling precision is not high enough, and man-machine interface is shortcoming such as close friend inadequately, has seriously restricted the performance of MCR performance and the popularization of product.Because MCR is applied in the technology that belongs to newer in the world, still belong to theory stage or trial run stage at home in addition, deeply do not launch on a large scale as yet, many ins and outs do not relate to.Cause that technical that is that all right is ripe.
The analytical work in theory of reactor controller is more in the reality; Design in the enforcement is comparatively complicated, adopts optical fiber communication more, causes enforcement and maintenance difficulties higher; Under 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
The object of the invention is exactly in order to address the above problem a kind of magnet controlled reactor controller to be provided, and it has reliable, and high-performance, cost are low, are fit to commercial Application, and the MCR controller architecture is reasonable, and the performance of MCR can access maximum performance.Be prone to the advantage of enforcement.
To achieve these goals, the present invention adopts following technical scheme:
A kind of magnet controlled reactor controller, it comprises controller module, and said controller module is the DSP+ARM framework, and said DSP is connected through dual port RAM with ARM, and controller module is connected respectively with signal of telecommunication output unit with analog module 1; Said analog module comprises the AD chip, and said AD chip is connected with the voltage collecting device that external electrical network is provided with, said controller module also with upper machine communication, said controller module, signal of telecommunication output unit are connected with power supply processing module respectively; Said signal of telecommunication output unit is connected with pulse transformer in the magnet controlled reactor.
Said DSP is connected with power supply processing module respectively with ARM; Said analog module comprises the AD chip; Said DSP input is connected with the AD chip; The DSP output is connected with signal of telecommunication output unit, and said DSP also is connected with nonvolatile memory with clock chip, and ARM in the said controller module and host computer are through serial or network interface communication.
Said DSP is connected with status indicator lamp.
Said voltage collecting device is a voltage transformer, and said AD chip also is connected with the current transformer that external electrical network is provided with.
Said signal of telecommunication output unit comprises the insulating cement plank, is provided with binding post at the insulating cement plank, and said binding post one end is connected with the DSP output pin, and the other end is connected with pulse transformer in the magnet controlled reactor through twisted-pair feeder or shielding conductor.
Said dsp chip is TMS320F28335; Dsp processor also connects JTAG chip internal test interface; Said ARM chip S3C2410A.
Said AD chip is connected with the CT current transformer with outside PT voltage transformer.
A kind of magnet controlled reactor controller control method, it comprises the steps
1) voltage sensor, the current sensor of DSP through electrical network carries out AC sampling and obtains current system mode; Said voltage sensor, current sensor carry out line voltage and line current collection to power network line, adopt comparison expression digital filter and two kinds of digital filter series connection of integration type digital filter associating filtering mode in the said AC sampling among the DSP; Subsequently the digital phase-locked frequency multiplier that carries out of filtered line voltage and line current is sampled, calculate through AD conversion interrupt service routine line voltage effective value, line current effective value, active power, reactive power, apparent power, each quantity of state of power factor to electrical network;
2) select one of voltage adjustment or two kinds of control models of power factor adjustment through the touch screen operation that is connected with ARM; Line voltage of gathering or line current sinusoidal signal obtain synchronizing signal through crossing zero balancing, with the zero crossing synchronizing signal as the phase shift benchmark; DSP calculates the phase shifting angle that the every phase of current time should be exported; Said control program comprises the closed loop control algorithm based on DSP;
3) DSP combines the phase shift benchmark according to the phase shift angle of calculating; 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 control magnetic valve type controllable reactor wherein, pulse transformer sends pulse train and ensures that magnetic valve type controllable reactor MCR goes up corresponding thyristor and excites reliably;
Said digital phase-locked frequency multiplier sampling comprises:
I), DSP has trapping module CAP to obtain the current demand signal frequency, the magnetic valve type controllable reactor of control is specially single-phase or three relative trapping module CAP accept or reject use as required; Said 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 the CAP1 input port, and through software arrangements, the hardware of CAP1 is caught the time of adjacent twice saltus step, i.e. cycle T; Thereby frequency is asked and is f=1/T, with its grid line voltage signal frequency as first-harmonic; Through line voltage signal frequency, the line current frequency of same phase obtains simultaneously;
Ii), with sample frequency be set at collect as the grid line voltage of first-harmonic or 128 times of line current signal frequency; The high order harmonic component of need analyzing is 32 times; Therefore low pass filter elects 50 * 32=3.2kHz as by frequency; The high order harmonic component of elimination more than 32 times prevents the aliasing of sampling effectively;
Iii), said 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 the open-loop design principle; This digital phase-locked frequency multiplier also is referred to as the homophase frequency multiplication;
Be input to when synchronizing frequency doubling signal on the ADSOC control mouth of AD module; Through software setting, make an AD conversion of synchronizing frequency doubling signal rising edge triggering each time, behind the AD EOC, trigger the AD interrupt service routine automatically; The result that storage is sampled each time in the interrupt service routine; Carrying out an AC sampling after per then 128 samplings finish calculates; Discrete formula by each physical quantity; Calculate line voltage, line current, active power, reactive power, apparent power, the power factor value of electrical network, realize data sharing, as the input variable of control and demonstration through dual port RAM and ARM;
Said closed loop control algorithm: controller has been taked two kinds of control strategies: the user selects the Different control pattern according to actual conditions through touch screen operation; Voltage adjustment control model and power factor adjustment control model; Voltage adjustment control model is controlled quentity controlled variable with the line voltage, through different reactive currents is provided, the voltage of electrical network is stabilized on the given operating voltage point; Power factor adjustment control model is a controlled quentity controlled variable with the power factor of electrical network, through different reactive currents is provided, the power factor of electrical network is stabilized on the power factor point of setting; According to control principle, as if being controlled target with voltage, given voltage-regulation desired value is introduced the voltage negative feedback; Through detected line voltage U and given reference voltage U
RefCompare, its deviation is input to the PI governing loop, and pi regulator calculates the phase-shift control angle of output, and the reactive power output size through circuits for triggering control MCR changes line voltage;
Equally, if will adjust control model with power factor, given power factor is regulated desired value, introduces the voltage and current feedback, calculates power factor of electric network as negative feedback; Through detected line voltage u and power network current i; Calculate power-factor angle
then and given reference voltage
compares, its deviation is input to the PI governing loop; Pi regulator calculates the phase-shift control angle that export, and the reactive power output size through circuits for triggering control MCR changes power factor of electric network;
On DSP, realize after two kinds of algorithm discretizations; The responsive time constant of the time constant of pi regulator and MCR itself adapts;
Line voltage of gathering or line current sinusoidal signal obtain synchronizing signal through crossing zero balancing; With the zero crossing synchronizing signal as the phase shift benchmark; DSP calculates the phase shift angle that the every phase of current time should be exported, and DSP produces triggering signal according to phase shift angle and the phase shift benchmark received; For the reliable thyristor that triggers, trigger impulse is carried out the method triggering that software homophase carrier wave is subdivided into a plurality of pulse trains to the pulse transformer employing.
Utilize dsp program to realize filter circuit; System has used two kinds of filters: two kinds of filter series connection of comparison expression filter and integration type filter; The integration type filter is realized the LPF of digital signal; The effectively shake of the signal of filtering and burr; And the filtering cut-off frequency is adjustable on a large scale, and the comparison expression filter is fit to the cut-off frequency condition with higher, and the two input that combines to strengthen signal of interest is handled;
Be the basis with the sampling thheorem theory; Promptly requiring sample frequency is more than 2 times of highest frequency in the measured signal frequency spectrum; Adopt the hardware synchronization sampling method to measured signal; Be that the synchronized sampling method is exactly the complete cycle of a uniform sampling uniformly-spaced, satisfy relational expression T=N Δ t between the sampling number N in measured signal cycle T, sampling time interval Δ t and one-period, that is: sample frequency be the measured signal frequency N doubly.
The grid frequency measurement circuit measuring goes out the 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 been realized the homophase frequency multiplication sampling to supplied with digital signal, and the ADSOC that sampled signal is input to DSP triggers the AD interruption;
Said grid frequency measurement circuit is to utilize DSP trapping module CAP that the synchronous signal acquisition of line voltage is passed through software arrangements, 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 the phase voltage of surveying; This time difference is the cycle of alternating voltage amount just; Thereby frequency can be asked and to be f=1/T.
Synchronizing frequency doubling signal is input on the ADSOC control mouth of DSP, through software setting, makes an AD conversion of synchronizing frequency doubling signal rising edge triggering each time, behind the AD EOC, triggers the AD interrupt service routine automatically;
The result that storage is sampled each time in the said AD interrupt service routine; After finishing, per then 128 samplings carry out that AC sampling calculates and based on the closed loop control algorithm of DSP; Simultaneously with counter O reset; Wait for the circulation after 128 samplings of next round finish; To sampling; Discretization is carried out in synchronous ac sampling to alternating voltage U, electric current I, active power P, reactive power Q, power factor
apparent power electric parameter, calculates voltage, electric current, active power, apparent power, reactive power, the power factor of electrical network, and said 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 control and demonstration;
Said alternating voltage U, electric current I discrete formula
Current effective value, voltage effective value, be defined as:
In the formula:
T---be the sampling period;
U (t)---instantaneous voltage;
I (t)---current instantaneous value.
After above two formula discretizations:
In the formula:
U (k)---the sampled value that voltage regulation is k time;
I (k)---the sampled value that electric current is the k time;
N-------sampling number in one-period;
Said active power P, reactive power Q, discrete formula
Being defined as of single-phase active power and reactive power:
Discretization obtains later on:
The calculating of said apparent power
Single-phase apparent power is:
The calculating of said power factor
The relation of single-phase active power, reactive power and multiple merit power is following:
S=P+jQ (0-10)
Can try to achieve power factor by formula (4-10) is:
Because power-factor angle
is so can be by computes:
The judgement of load characteristic
When Q>0,
load is a perception; When Q<0,
load is a capacitive;
Said closed loop control algorithm based on DSP is that through touch-screen selection Different control pattern, said Different control pattern comprises, voltage adjustment and power factor adjustment.Voltage adjustment control model is controlled quentity controlled variable with the line voltage, through different reactive currents is provided, the voltage of electrical network is stabilized on the given operating voltage point; Power factor adjustment control model is a controlled quentity controlled variable with the power factor of electrical network, through 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 through judgement, as if being controlled target with voltage, just by given voltage-regulation desired value, introduces the voltage negative feedback, through detected phase line voltage U and given reference voltage U
RefCompare, its deviation is input to the PI governing loop; Pi regulator calculates the phase-shift control angle that export, and the reactive power output size through phase-shift trigger circuit control MCR changes line voltage;
Equally,, just regulate desired value, introduce voltage and current and feed back, calculate power factor of electric network as negative feedback by given power factor as if being controlled target with the power factor; Through detected line voltage u and power network current i; Calculate power-factor angle
then and given reference voltage
compares; Its deviation is input to the PI governing loop; Pi regulator calculates the phase-shift control angle that export; Reactive power output size through phase-shift trigger circuit control MCR; Change power factor of electric network, on DSP, realize after two kinds of situation discretizations;
The performing step of said phase-shift trigger circuit: among the DSP filtered synchronizing signal is outputed to its inner triggering signal generative circuit; The triggering signal generative circuit is also accepted the signal from the ARM data receiver circuit; Said data receiver circuit is the self-defined parallel bus of a 4bit; Data receiver circuit receives the control signal of being sent through two-way RAM by ARM, and each the phase trigger angle signal that receives is exported to the triggering signal generative circuit; The burst signal that is generated the appointment angle of flow by the triggering signal generative circuit removes to control MCR; Said triggering signal generative circuit is: sinusoidal signal obtains synchronizing signal through the zero passage comparison circuit, and synchronizing signal is input to DSP, through being sent to the circuits for triggering generative circuit behind the DSP digital filtering.Through obtaining counter equivalence waveform behind the integration counter; The given angle of flow that obtains according to DSP then; Counter equivalence waveform is carried out the PWM conversion obtain the homophase carrier signal, behind the described homophase carrier signal output DSP, drive MCR and go up corresponding thyristor.
Said ARM is provided with the man-machine interaction program, and it comprises and is divided into three parts: keyboard decoding circuit program, Keyboard Control program, display routine;
Said keyboard decoding circuit program is: in ARM inside the MCR controller has been designed 15 function buttons and a reset key altogether; 15 function buttons are become the 4bit data be input to two-way RAM; The prerequisite of decoding is that the hypothesis user only carries out the operation of a button at synchronization; If supress a plurality of keys simultaneously, confirm button with keypad priority;
The Keyboard Control program is a critical function of man-machine interaction, and the user can carry out picture switching, parameter input, control command input operation through keyboard.
Said display routine comprises LCD initialization function and interface display function.Thus, having reached the magnetic valve type controllable reactor real-time working information that the user is needed is shown on the LCD.
Technical essential of the present invention
(1) controller hardware framework: hardware platform adopts multiprocessor Collaborative Control pattern-DSP+ARM framework, and dsp chip is the last word TMS320F28335 of TI company, and it mainly is responsible for the computing of Digital Signal Processing and core algorithm.The ARM chip is 16/32 RISC (reduced instruction set computer) microprocessor S3C2410A based on ARM920T nuclear of Samsung company, mainly is responsible for the processing and the HMI (human-computer interaction function) of peripheral signal.Realize data sharing through dual port RAM between two kinds of control chips.Extend out simultaneously at a high speed, high accuracy 16 potential differences divide AD to realize quick undistorted sampling, satisfy the requirement of industry spot speed and precision well.
(2) controller software is realized: on software, adopted hierarchical control, modular thought, made every effort to realize that control is succinct reliably, software can be assembled, maintenance upgrade is purpose easily.
It at first is the realization (core layer) that hierarchical control: DSP is responsible for the functions such as realization, storage and exchange of quick high accuracy sampling, core algorithm; ARM be responsible for liquid crystal display control, touch screen soft-keyboard response and with the communication function (Communication Layer) of ipc monitor system.
Next is the thought that has adopted modularization programming; DSP program and ARM program are strict with modular programming principle, have carried out careful functions of modules and have cut apart and realize, make whole procedure possess higher modularization level; Better readable, the later maintenance upgrading easily.
The major control process prescription is following:
DSP obtains current system mode through AC sampling or instantaneous reactive Sampling techniques, and each quantity of state that obtains is realized data sharing through dual port RAM and ARM;
Calculate the current pilot angle of system through control program and each defence program;
The pilot angle that obtains is used for controlling magnet controlled reactor through signal of telecommunication pulse;
ARM be responsible for showing with the processing of touch screen operation and with the communication of ipc monitor system.
Increase surge protection and electrostatic protection function during the design of system hardware schematic diagram; Undertaken dividing by each functional module during the PCB layout drawing carefully, take into full account the EMC characteristic, realized that height/low-voltage circuit separates the separation of analog/digital circuit, the separation of low speed/high speed circuit; According to soft project design philosophy from top to bottom, divide module to each item function during software design, each module's cohesion is strong, the degree of coupling is low, be prone to upgrade maintenance.
Controller architecture; Design 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.Internal circuit board carries out Module Division by function and principle of EMC, and the size of each module all designs in strict accordance with standard.Controller is divided into by each functional module: power module, analog module, digital quantity input module, digital quantity output module, signal of telecommunication output unit, bus module etc.Have strong interference immunity, be prone to plurality of advantages such as debugging, easy care by controller after the function division module.
The operation principle of magnetic valve type controllable reactor
Through 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 development potentiality was wherein arranged 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 the electric power system, payes attention to and obtained preliminary application widely having received in recent years.Compare with existing other reactive power compensator, MCR has advantages such as suitable voltage range is wide, reactive capability is big, reliability is high, harmonic wave is little, cost is low, maintenance is simple, is fit to large-scale promotion and uses.
In the actual motion of MCR, need and the remote monitoring of comprehensive automation system of transformer substation Communication Realization.Comprehensive automation system of transformer substation generally adopts serial communication or network mode.Also the 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 detect and adapt to substation operation state (apportion, off-the-line side by side) automatically;
3) can take corresponding control strategies according to controlled target (idle or voltage), accurately control;
4) can the electric network reactive-load situation record of certain hour be stored, the user can read these data through serial communication mode;
5) can realize controller Long-distance Control controlled reactor, realize the installation that separates of body and controller;
6) man-machine interface is friendly;
7) can satisfy on-the-spot Electro Magnetic Compatibility requirement;
8) the 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 that improves electrical network, adjustment line voltage, compensating power and over-voltage bigger application potential is arranged all.
Description of drawings
Fig. 1 is magnet controlled reactor controller principle figure;
The magnetic circuit sketch map of Fig. 2 A magnetic valve type controllable reactor;
Fig. 2 B magnetic circuit equivalent schematic;
Fig. 3 is a DSP principle of phase lock loop block diagram;
Fig. 4 is a MCR voltage mode control sketch map;
Fig. 5 is a MCR power factor controlling pattern diagram;
Fig. 6 is a 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 present invention is described further.
Among 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; Said controller module 5 also and upper machine communication, said 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 the DSP+ARM framework, and said DSP is connected with power supply processing module 6 respectively with ARM; DSP is connected through dual port RAM with ARM; Analog module 1 comprises the AD chip; Said DSP input is connected with the AD chip; The DSP output is connected with signal of telecommunication output unit, and said DSP also is connected with nonvolatile memory 8 with clock chip 7, and ARM in the said controller module 5 and host computer 2 are through serial or network interface communication.
Signal of telecommunication output unit 3 is connected with power supply processing module 6; Said signal of telecommunication output unit 1 is connected with pulse transformer in the magnet controlled reactor.DSP is connected with status indicator lamp 4.Dsp chip is TMS320F28335; ARM chip S3C2410A.The AD chip is connected with CT with the PT that external electrical network is provided with.
The pulse-triggered shielded type cable is convenient to outdoor wiring, and controller is a portable construction, the design of subrack formula, and dustproof, waterproof, shockproof are fit to outdoor use,
Power supply processing module is the AC/DC modular power source for the ac-dc conversion device.Power supply processing module 6 provides working power for dsp chip and ARM core and dual port RAM.
The electrorheological voltage that PT or CT connect successively is I/V circuit, low-pass filter circuit, double-click commentaries on classics single-level circuit, output protection circuit; Said PT or CT comprise CT that the PT that is connected with main transformer, main transformer connect, be equipped with and become the PT that connects, be equipped with and become the CT that connects, i.e. main transformer PT, CT and become PT, CT fully.
Said outside extension storage device is EEPROM; Said clock signal device comprises the calendar clock chip of expansion, and said calendar clock is DS1302, and said calendar clock chip is provided with crystal oscillator, and said crystal oscillator frequency is 30MHZ; Said display unit is a LCD display, and LCD display is a touch-screen; Or utilize controller module 5 communication interfaces to connect human-computer interaction device; Like keyboard; Said keyboard comprises 15 function keys and a reset key, said 15 function keys comprise rise, move, stop, communication, downward modulation, confirm, cancel, check, automatically, manually, be provided with, to the time and the upper and lower, left and right options button; Said keyboard is the effective type of low level, and the time constant of said reset key is greater than other keys; Said dsp processor also connects JTAG chip internal test interface.
Fig. 2 A is a magnetic valve type controllable reactor magnetic circuit sketch map; (area is Ab1 to iron core by the bigger part of area (area is Ab, and length is l, is called " large tracts of land core packet " below) and the smaller part of area; Length is lt, is called " magnet valve core packet " below) be in series.
In the entire capacity adjustable range of magnetic valve type controllable reactor, the operating state of large tracts of land core packet is in the unsaturation linear zone of magnetic circuit all the time, and its magnetic resistance is very little with respect to the magnet valve core packet, can ignore.The magnet valve part magnetic line of force is divided into two parts, and a part is through the magnet valve iron core, and magnetic resistance is designated as Rt, and another part is through air gap, and equivalent magnetic resistance is designated as Rq
Fig. 2 B magnetic valve type controllable reactor magnetic circuit can equivalent schematic.Among the figure, F is the magnetic circuit magnetic potential, and Φ is the magnetic circuit total magnetic flux,
(μ
0Be 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 through electrical network carries out AC sampling and obtains current system mode; Said voltage sensor, current sensor carry out line voltage and line current collection to power network line, adopt comparison expression digital filter and two kinds of digital filter series connection of integration type digital filter associating filtering mode in the said AC sampling among the DSP; Subsequently the digital phase-locked frequency multiplier that carries out of filtered line voltage and line current is sampled, calculate through AD conversion interrupt service routine line voltage effective value, line current effective value, active power, reactive power, apparent power, each quantity of state of power factor to electrical network;
2) select one of voltage adjustment or two kinds of control models of power factor adjustment through the touch screen operation that is connected with ARM; Line voltage of gathering or line current sinusoidal signal obtain synchronizing signal through crossing zero balancing, with the zero crossing synchronizing signal as the phase shift benchmark; DSP calculates the phase shifting angle that the every phase of current time should be exported; Said control program comprises the closed loop control algorithm based on DSP;
3) DSP combines the phase shift benchmark according to the phase shift angle of calculating; 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 control magnetic valve type controllable reactor wherein, pulse transformer sends pulse train and ensures that magnetic valve type controllable reactor MCR goes up corresponding thyristor and excites reliably;
Said digital phase-locked frequency multiplier sampling comprises:
I), DSP has trapping module CAP to obtain the current demand signal frequency, the magnetic valve type controllable reactor of control is specially single-phase or three relative trapping module CAP accept or reject use as required; Said 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 the CAP1 input port, and through software arrangements, the hardware of CAP1 is caught the time of adjacent twice saltus step, i.e. cycle T; Thereby frequency is asked and is f=1/T, with its grid line voltage signal frequency as first-harmonic; Through line voltage signal frequency, the line current frequency of same phase obtains simultaneously;
Ii), with sample frequency be set at collect as the grid line voltage of first-harmonic or 128 times of line current signal frequency; The high order harmonic component of need analyzing is 32 times; Therefore low pass filter elects 50 * 32=3.2kHz as by frequency; The high order harmonic component of elimination more than 32 times prevents the aliasing of sampling effectively;
Iii), said 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 the open-loop design principle; This digital phase-locked frequency multiplier also is referred to as the homophase frequency multiplication;
Be input to when synchronizing frequency doubling signal on the ADSOC control mouth of AD module; Through software setting, make an AD conversion of synchronizing frequency doubling signal rising edge triggering each time, behind the AD EOC, trigger the AD interrupt service routine automatically; The result that storage is sampled each time in the interrupt service routine; Carrying out an AC sampling after per then 128 samplings finish calculates; Discrete formula by each physical quantity; Calculate line voltage, line current, active power, reactive power, apparent power, the power factor value of electrical network, realize data sharing, as the input variable of control and demonstration through dual port RAM and ARM;
Said closed loop control algorithm: controller has been taked two kinds of control strategies: the user selects the Different control pattern according to actual conditions through touch screen operation; Voltage adjustment control model and power factor adjustment control model; Voltage adjustment control model is controlled quentity controlled variable with the line voltage, through different reactive currents is provided, the voltage of electrical network is stabilized on the given operating voltage point; Power factor adjustment control model is a controlled quentity controlled variable with the power factor of electrical network, through different reactive currents is provided, the power factor of electrical network is stabilized on the power factor point of setting; According to control principle, as if being controlled target with voltage, given voltage-regulation desired value is introduced the voltage negative feedback; Through detected line voltage U and given reference voltage U
RefCompare, its deviation is input to the PI governing loop, and pi regulator calculates the phase-shift control angle of output, and the reactive power output size through circuits for triggering control MCR changes line voltage;
Equally, if will adjust control model with power factor, given power factor is regulated desired value, introduces the voltage and current feedback, calculates power factor of electric network as negative feedback; Through detected line voltage u and power network current i; Calculate power-factor angle
then and given reference voltage
compares, its deviation is input to the PI governing loop; Pi regulator calculates the phase-shift control angle that export, and the reactive power output size through circuits for triggering control MCR changes power factor of electric network;
On DSP, realize after two kinds of algorithm discretizations; The responsive time constant of the time constant of pi regulator and MCR itself adapts;
Line voltage of gathering or line current sinusoidal signal obtain synchronizing signal through crossing zero balancing; With the zero crossing synchronizing signal as the phase shift benchmark; DSP calculates the phase shift angle that the every phase of current time should be exported, and DSP produces triggering signal according to phase shift angle and the phase shift benchmark received; For the reliable thyristor that triggers, trigger impulse is carried out the method triggering that software homophase carrier wave is subdivided into a plurality of pulse trains to the pulse transformer employing.
Under certain conditions; Application like (40HZ-60HZ) of reactor about power frequency 50HZ; Also can take directly to gather line voltage and line current signal in the power network line; Control in real time through DSP, phase-shift control angle is provided, satisfy and improve line voltage and the needs that improve power factor of electric network.
Utilize dsp program to realize filter circuit; System has used two kinds of filters: two kinds of filter series connection of comparison expression filter and integration type filter; The integration type filter is realized the LPF of digital signal; The effectively shake of the signal of filtering and burr; And the filtering cut-off frequency is adjustable on a large scale, and the comparison expression filter is fit to the cut-off frequency condition with higher, and the two input that combines to strengthen signal of interest is handled;
Be the basis with the sampling thheorem theory; Promptly requiring sample frequency is more than 2 times of highest frequency in the measured signal frequency spectrum; Adopt the hardware synchronization sampling method to measured signal; Be that the synchronized sampling method is exactly the complete cycle of a uniform sampling uniformly-spaced, satisfy relational expression T=N Δ t between the sampling number N in measured signal cycle T, sampling time interval Δ t and one-period, that is: sample frequency be the measured signal frequency N doubly.
The grid frequency measurement circuit measuring goes out the 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 been realized the homophase frequency multiplication sampling to supplied with digital signal, and the ADSOC that sampled signal is input to DSP triggers the AD interruption;
Said grid frequency measurement circuit is to utilize DSP trapping module CAP that the synchronous signal acquisition of line voltage is passed through software arrangements, 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 the phase voltage of surveying; This time difference is the cycle of alternating voltage amount just; Thereby frequency can be asked and to be f=1/T.
Synchronizing frequency doubling signal is input on the ADSOC control mouth of DSP, through software setting, makes an AD conversion of synchronizing frequency doubling signal rising edge triggering each time, behind the AD EOC, triggers the AD interrupt service routine automatically;
The result that storage is sampled each time in the said AD interrupt service routine; After finishing, per then 128 samplings carry out that AC sampling calculates and based on the closed loop control algorithm of DSP; Simultaneously with counter O reset; Wait for the circulation after 128 samplings of next round finish; To sampling; Discretization is carried out in synchronous ac sampling to alternating voltage U, electric current I, active power P, reactive power Q, power factor
apparent power electric parameter, calculates voltage, electric current, active power, apparent power, reactive power, the power factor of electrical network, and said 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 control and demonstration;
Alternating voltage U, electric current I discrete formula
Current effective value, voltage effective value, be defined as:
In the formula:
T---be the sampling period;
U (t)---instantaneous voltage;
I (t)---current instantaneous value.
After above two formula discretizations:
In the formula:
U (k)---the sampled value that voltage regulation is k time;
I (k)---the sampled value that electric current is the k time;
N-------sampling number in one-period;
Said active power P, reactive power Q, discrete formula
Being defined as of single-phase active power and reactive power:
Discretization obtains later on:
The calculating of said apparent power
Single-phase apparent power is:
The calculating of said power factor
The relation of single-phase active power, reactive power and multiple merit power is following:
S=P+jQ (0-22)
Can try to achieve power factor by formula is:
Because power-factor angle
is so can be by computes:
The judgement of load characteristic
When Q>0,
load is a perception; When Q<0,
load is a capacitive;
Said closed loop control algorithm based on DSP is that through touch-screen selection Different control pattern, said Different control pattern comprises, voltage adjustment and power factor adjustment.Voltage adjustment control model is controlled quentity controlled variable with the line voltage, through different reactive currents is provided, the voltage of electrical network is stabilized on the given operating voltage point; Power factor adjustment control model is a controlled quentity controlled variable with the power factor of electrical network, through 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 through judgement, as if being controlled target with voltage, just by given voltage-regulation desired value, introduces the voltage negative feedback, through detected phase line voltage U and given reference voltage U
RefCompare, its deviation is input to the PI governing loop; Pi regulator calculates the phase-shift control angle that export, and the reactive power output size through phase-shift trigger circuit control MCR changes line voltage;
Equally,, just regulate desired value, introduce voltage and current and feed back, calculate power factor of electric network as negative feedback by given power factor as if being controlled target with the power factor; Through detected line voltage u and power network current i; Calculate power-factor angle
then and given reference voltage
compares; Its deviation is input to the PI governing loop; Pi regulator calculates the phase-shift control angle that export; Reactive power output size through phase-shift trigger circuit control MCR; Change power factor of electric network, on DSP, realize after two kinds of situation discretizations;
Said ARM is provided with the man-machine interaction program, and it comprises and is divided into three parts: keyboard decoding circuit program, Keyboard Control program, display routine;
Said keyboard decoding circuit program is: in ARM inside the MCR controller has been designed 15 function buttons and a reset key altogether; 15 function buttons are become the 4bit data be input to two-way RAM; The prerequisite of decoding is that the hypothesis user only carries out the operation of a button at synchronization; If supress a plurality of keys simultaneously, confirm button with keypad priority;
The Keyboard Control program is a critical function of man-machine interaction, and the user can carry out picture switching, parameter input, control command input operation through keyboard.
Said display routine comprises LCD initialization function and interface display function.Thus, having reached the magnetic valve type controllable reactor real-time working information that the user is needed is shown on the LCD.
Though the above-mentioned accompanying drawing specific embodiments of the invention that combines is described; But be not restriction to protection range of the present 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 need not pay various modifications that creative work can make or distortion still in protection scope of the present invention.