CN101247046A - Harmonic wave dynamic managing and reactive-load dynamic compensation compound control method and implementing device thereof - Google Patents

Abstract

The present invention discloses a harmonic dynamic treating and reactive dynamic compensation composite control method and the realizing device, wherein, the realizing device comprises a main device and a control device. The main device comprises a HAPF, a SVC which is composed of a mechanical switching capacitor set that is Y-shape connected and a thyristor control reactor that is delta connected. The control device comprises a voltage and current mutual inductor which are accessed into the sampling module, and a DSP controller, an industrial controlling device, a communication module, a MSC logic control circuit, a RCR admittance-angle calculating module, a PWM signal generating module, and light end transmitter, a light end receiver, and MSC, TCR and HAPF which are lastly accessed into the main device with the insulating and power amplifying circuit. The invention executes dynamic coordination control to the hybrid active electric power wave filter and static reactive compensator, has excellent dynamic and static properties and robustness, and better adaptability.

Description

Harmonic wave dynamic managing and reactive-load dynamic compensation compound control method and implement device thereof

Technical field

The invention belongs to flexible AC electrical power trans mission/distribution system control technology field, particularly a kind of harmonic wave dynamic managing and reactive-load dynamic compensation compound control method and implement device thereof.

Background technology

Extensively there is a large amount of inductive loads in the electrical power trans mission/distribution system, these loads can consume a large amount of reactive powers in distribution system, the power factor of reduction system causes the line voltage distribution loss to strengthen and electric energy loss increases, and directly affects the economic benefit of electric power enterprise.In addition, for such as arc furnace, these impact load or burden without work of rolling mill, the big ups and downs that also can produce voltage worsen the power supply quality of electrical network.The effective ways that address these problems carry out reactive power compensation exactly.Static Var Compensator (SVC) has been widely used in reactive power compensation at present, and obtains considerable income, has that control response speed is fast, loss is less, reliability is high, can be by advantage such as control mutually.The SVC device generally has at present: fixed capacitor-thyristor-controlled reactor (FC-TCR), mechanical type switched capacitor-thyristor-controlled reactor (MSC-TCR), thyristor switchable capacitor-thyristor-controlled reactor (TSC-TCR), these SVC devices all pass through thyristor-controlled reactor (TCR) compensate the perception idle, capacitor compensates capacitive reactive power.

The operation principle of TCR itself has determined it can produce harmonic wave, and it is very harsh will reaching the balance movement condition during actual motion, can not satisfy usually.Imbalance will cause the uncharacteristic harmonics that TCR produces like this, and 3 times, 5 times, 7 times, 11 times, 13 subharmonic flow in the electrical network, causes electric network pollution.Development along with power electronic technology, increased a large amount of nonlinear loads in the power supply-distribution system, particularly with the static converter of on-off mode work, and other nonlinear loads such as arc furnace, electric welding machine, transformer, electric rotating machine, the capital produces the harmonic wave of different frequency and amplitude in electrical network, power system security, stable, economical operation are constituted huge threat.In order to build " green electrical network ", go back the electric circumstance of a cleaning of electrical network, should take effective harmonic wave to suppress means.Active Power Filter-APF (APF-Active Power Filter), it is a kind of power electronic equipment, can carry out dynamic compensation to frequency and the big or small harmonic wave that all changes, compensation characteristic is not subjected to the influence of electric network impedance and frequency change, can obtain than the better compensation effect of passive filter (PF-Passive Filter), be a kind of desirable harmonic compensation device.

At present, be respectively to reactive power compensation and harmonic wave control in the electric power system, carry out individually, not to unite by unified physical model to administer, be not easy to safeguard, less economical, the situation of attending to one thing and lose sight of another often appears.Harmonic wave for TCR produces generally adopts passive power filter to carry out harmonic wave control, its outstanding advantage be simple in structure, operational reliability is high, operating cost is low.But the filtering performance of passive power filter is subjected to the influence of mains frequency, impedance bigger, and passive filter is made up of jumbo reactor and capacitor, and machine volume is huge, the cost height.Existing document discloses employing APF and administered harmonic wave, and (TSC) compensates capacitive reactive power with thyristor switchable capacitor, and the weak point of existence is: the capacity of APF is less, will certainly increase cost if enlarge its capacity; TSC just compensates capacitive reactive power, and it is idle to compensate perception, just powerless for the occasion of capacitive reactive power surplus; A little whole system is controlled for starting with waveform, the dynamic of controller, stability, robustness, adaptability are relatively poor.By comparison, administer harmonic wave with HAPF, capacity is bigger, not only is fit to the low pressure place, but also is fit to the mesohigh place.

Summary of the invention

The objective of the invention is to overcome the deficiencies in the prior art and at the problem that exists, a kind of harmonic wave dynamic managing and reactive-load dynamic compensation compound control method and implement device thereof are proposed, based on SVC and HAPF design composite control method mixed active electric power filter and Static Var Compensator are carried out dynamic coordinate control, have good dynamically, static properties, robustness, adaptability are stronger.

For achieving the above object, the technical solution adopted in the present invention is: a kind of harmonic wave dynamic managing and reactive-load dynamic compensation compound control method may further comprise the steps:

(1) voltage, current transformer detection of grid bus three-phase voltage u _a, u _b, u _c, three-phase current i _a, i _b, i _cStatic Var Compensator output current i _Svc, comprise TCR, MSC output current i _Tcr, i _MscStatic Var Compensator output voltage u _SvcLoad current i _L

(2) detect the voltage draw, current signal by 2 MAX125 samplings after, send into dsp controller; Calculate three-phase voltage first-harmonic effective value V by dsp controller ₁, grid side harmonic current i _Sh, load-side harmonic current i _Lh, TCR harmonic current i _Tcr

(3) calculate fundamental voltage effective value V ₁With given magnitude of voltage V _RefDifference V _e, difference draws SVC controlled quentity controlled variable admittance B after regulating through neural network tuned proportion integration differentiation PI controller _Ref, its discrete control law is shown below:

B _ref(k)＝B _ref(k-1)+k _p1[V _e(k)-V _e(k-1)]+k _i1[V _e(k)]

(4) according to B _RefCalculate TCR, MSC compensation admittance B respectively _Tcr, B _Msc, and control TCR, MSC circuits for triggering provide thyristor trigger impulse, capacitor switching level, make the idle desired value that meets of SVC compensation;

(5) calculate current i _ShWith given mains by harmonics current i _Sh ^*Difference DELTA i _Sh, to difference DELTA i _ShRegulate the compensation rate that obtains the mains by harmonics electric current; Calculate current i _LhWith give fixed load harmonic current i _Lh ^*Difference DELTA i _Lh, to difference DELTA i _LhRegulate the compensation rate that obtains the load harmonic current; Calculate current i _TcrWith given TCR harmonic current i _Tcr ^*Difference DELTA i _Tcr, to difference DELTA i _TcrRegulate the compensation rate that obtains the TCR harmonic current;

(6) compensation rate of integrated load side harmonic current and mains by harmonics electric current, TCR harmonic current, the control reference signal of active filter is:

U＝K ₁·Δi _tcr+K ₂·Δi _Lh+K ₃·i _sh

Through drawing pwm signal after the modulation of high frequency triangular carrier, the break-make of control Active Power Filter-APF switching device IGBT is carried out the comprehensive regulation to harmonic wave;

(7) repeat above step, up to reaching idle compensation target.

The present invention also comprises a kind of cooperation control device based on resonance injection type hybrid active electric filter HAPF and Static Var Compensator SVC of realizing above-mentioned control method, comprise main device and control device, main device comprises the Static Var Compensator SVC that resonance injection type hybrid active electric filter HAPF, the thyristor-controlled reactor TCR that is connected with triangle by the mechanical type opening-closing capacitor bank MSC of star-like connection form; Active Power Filter-APF is connected in parallel by coupling transformer and first-harmonic resonance circuit behind the LC filter filtering, again through injecting capacitor C _GInsert electrical network; Every phase thyristor-controlled reactor is in series by the air core reactor of an antiparallel a pair of thyristor and a linearity and forms, and three-phase thyristor control reactor is connected into during △ shape is connected to the grid; Three-phase mechanical type switched capacitor is connected into Y shape, in being connected to the grid by controlled mechanical switch; Control device comprises the voltage that inserts sampling module, current transformer, the output of described sampling module inserts dsp controller, wherein there is industrial computer to be connected by communication module and dsp controller are two-way, the output of dsp controller inserts the MSC logic control circuit respectively, TCR admittance-angle calculation module, pwm signal generation module, MSC logic control circuit wherein, TCR admittance-angle calculation module is respectively by the MSC circuits for triggering, TCR circuits for triggering and pwm signal generation module together connect the light inputting end transmitter, insert light end receiver by optical fiber again, light end receiver is by isolating and power amplification circuit inserts MSC in the main device respectively, TCR and HAPF.

Operation principle of the present invention is described in detail as follows:

Described cooperation control device based on resonance injection type hybrid active electric filter HAPF and Static Var Compensator SVC, at first with normal voltage, current signal after voltage, the current transformer conversion, the input sample module is carried out filtering, is rejected Error processing; Carry out the controlled quentity controlled variable that computing draws whole device by dsp controller then, controlled quentity controlled variable is respectively through the MSC logic control circuit, TCR admittance-angle calculation module, draw controlled quentity controlled variable separately after the pwm signal generation module, the circuits for triggering of controlling MSC, TCR, HAPF respectively provide triggering signal, through the undistorted scene that is transferred to of optical fiber; Triggering signal drove the mechanical switch of MSC device, the thyristor of TCR device, the IGBT (insulated gate bipolar transistor npn npn) of resonance injection type hybrid active electric filter device afterwards through isolation and power amplification circuit, thereby realized the comprehensive regulation of Harmonious Waves in Power Systems and idle dynamic compensation.Dsp controller is sent to industrial computer to real-time voltage, the current signal gathered by communication module, and displays with the form of various figures, curve.

Wherein the SVC system is made up of the thyristor-controlled reactor TCR that the mechanical type opening-closing capacitor bank MSC of star-like connection is connected with triangle, the MSC coarse adjustment provides differential capacitive reactive power, it is idle that TCR produces continuously adjustable perception, the two is idle with perception in conjunction with producing continuously adjustable capacitive, detailed process is: idle by real-time detection of grid load, determine the group number of the capacitor group of input to produce differential capacitive reactive power according to idle needs, under the situation of capacitive reactive power surplus, regulate perceptual idle among the TCR, thereby finally make the idle Q of system _N=Q _V(system is required)-Q _MSC+ Q _TCR=constant or 0;

The resonance injection type mixed active electric power filter comprises Active Power Filter-APF and passive filter group, the output of described Active Power Filter-APF and the input of Y-connected coupling transformer link, each of the three-phase output of coupling transformer is connected in parallel with the first-harmonic resonance circuit, and behind second capacitor filtering, insert electrical network, the first-harmonic resonance circuit is composed in series by electric capacity and inductance, and its frequency of oscillation is the electrical network fundamental frequency.

Harmonic wave dynamic managing of the present invention and reactive-load dynamic compensation compound control method and implement device are realized, dynamically compensation idle in real time to system with Static Var Compensator SVC; With resonance injection type mixed active electric power filter HAPF mains by harmonics, load harmonic wave, TCR harmonic wave are carried out the comprehensive regulation, can realize dynamic improvement, avoided shortcomings such as the static improvement speed of traditional TCR harmonic wave is slow, real-time difference harmonic wave; Active filter mainly bears harmonic voltage and does not bear system's fundamental voltage, and the fundamental current of inflow seldom thereby helps reducing the capacity of active filter, reduces cost; Idle and harmonic wave are carried out compound control, the shortcoming of having avoided traditional reactive power compensation, harmonic wave control to do things in his own way, conflict mutually.

Description of drawings

Fig. 1 is the structured flowchart of the control device of cooperation described in the present invention.

Fig. 2 is the circuit structure diagram of main device in the control device of cooperation described in the present invention.

Fig. 3 is the control method structure chart that dsp controller is realized among Fig. 1.

Fig. 4 is neural network structure figure in the described control method of Fig. 3.

Embodiment

As shown in Figure 1, bus three-phase voltage u _a, u _b, u _c, Static Var Compensator output voltage u _SvcThree-phase current i _a, i _b, i _cStatic Var Compensator output current i _SvcLoad current i _LActive Power Filter-APF HAPF output current i _HAPF, draw corresponding small-signal through overvoltage, current transformer after detecting respectively, through sampling module, after promptly 2 totally 16 passage MAX125 chips are sampled, be input to dsp controller, and calculate three-phase voltage first-harmonic effective value V ₁, grid side harmonic current i _Sh, load-side harmonic current i _Lh, TCR harmonic current i _TcrBy the RS485 communication module all acquired signal are sent to industrial computer, and display with the form of various figures, curve.Provide expectation mains by harmonics current i by the input module keyboard in the host computer _Sh ^*Value, expectation load harmonic current i _Lh ^*Value, expectation TCR harmonic current i _Tcr ^*Value, desirable system magnitude of voltage V _Ref, send dsp controller to by communication module.The control signal that dsp controller calculates by compound control shown in Figure 3, the circuits for triggering of controlling HAPF, MSC, TCR respectively provide triggering signal, through the undistorted scene that is transferred to of optical fiber, signal drove IGBT, mechanical switch, thyristor afterwards through isolation and power amplification circuit, thereby realized the comprehensive regulation of Harmonious Waves in Power Systems and idle dynamic compensation.

As shown in Figure 2, the overall structure of harmonic wave dynamic managing and reactive-load dynamic compensation compound control method mainly by: resonance injection type hybrid active electric filter, thyristor-controlled reactor, mechanical type switched capacitor three parts are formed; Resonance injection type hybrid active electric filter HAPF comprises Active Power Filter-APF APF and passive filter group, A phase injection branch composes in series single tuned filter by capacitor C G, capacitor C 1, inductance L 1, capacitor C 1, inductance L 1 are composed in series A phase first-harmonic resonance circuit, the series arm of capacitor C 2, inductance L 2 and capacitor C 3, inductance L 3 series arms are two single tuned filters, are tuned at specific harmonic frequency place.Active Power Filter-APF HAPF is connected in parallel by coupling transformer and first-harmonic resonance circuit behind the LC filter filtering, inserts electrical network through injecting capacitor C G again, and the two-phase injection circuit links identical with A in addition; Every phase thyristor-controlled reactor is in series by the air core reactor of an antiparallel a pair of thyristor and a linearity and forms, and three-phase thyristor control reactor is connected into during △ shape is connected to the grid; Three-phase mechanical type switched capacitor is connected into Y shape, in being connected to the grid by controlled mechanical switch.

As shown in Figure 3, the control flow of dsp controller comprises SVC neural network tuned proportion integration differentiation PI control and the compound control of resonance injection mixed active power filter HAPF; Wherein SVC neural network tuned proportion integration differentiation PI controls main process and is: fundamental voltage effective value V ₁With given magnitude of voltage V _RefDifference be V _e, V _eDraw SVC controlled quentity controlled variable B by neural network tuned proportion integration differentiation PI control algolithm _Ref, as the formula (1).Neural net NN adopts 3 layers of forward direction BP network, and the learning algorithm of network adopts neural net multivariable learning algorithm, as shown in Figure 4; By self study, the adjustment weight coefficient of neural net, the parameter K of regulating the PI controller according to the running status of system _p, K _iB _RefAfter TCR/MSC admittance computing module (being formula 2) calculating, obtain each self-admittance B of MSC, TCR respectively _Msc, B _Tcr, its size has determined the quantity of MSC input and the size of TCR conducting angle; B _TcrBe transformed into radian (angle of flow of thyristor) through admittance-angle function and controlled what of perceptual idle input electrical network; B _MscThrough MSC logic controller output high level or low level, come control capacitor to drop into the number of electrical network.

B _ref(k)＝B _ref(k-1)+k _p1[V _e(k)-V _e(k-1)]+k _i1[V _e(k)] (1)

$\left\{\begin{array}{c}{B}_{\mathrm{ref}}=(1-\frac{B_{\mathrm{msc}}}{B_{\mathrm{\σ}}})B_{\mathrm{msc}}+(1-\frac{2B_{\mathrm{msc}}+B_L}{B_{\mathrm{\σ}}})B_{\mathrm{tcr}}\\ B_{\mathrm{msc}}={\mathrm{nB}}_C\end{array}\right.---\left(2\right)$

B in the formula (2) _σFor transformer susceptance (regarding ideal transformer here as) value is 1, n=1,2... are that capacitor drops into number.

Wherein the resonance injection type mixed active electric power filter is controlled main process and is: calculate current i _ShWith given mains by harmonics current i _Sh ^*Difference DELTA i _Sh, to difference DELTA i _ShRegulate the compensation rate that obtains the mains by harmonics electric current; Calculate current i _LhWith give fixed load harmonic current i _Lh ^*Difference DELTA i _Lh, to difference DELTA i _LhRegulate the compensation rate that obtains the load harmonic current; Calculate current i _TcrWith given TCR harmonic current i _Tcr ^*Difference DELTA i _Tcr, to difference DELTA i _TcrRegulate the compensation rate that obtains the TCR harmonic current.The compensation rate of integrated load side harmonic current and mains by harmonics electric current, TCR harmonic current, the control reference signal of active filter is:

U＝K ₁·Δi _tcr+K ₂·Δi _Lh+K ₃·i _sh (3)

U draws the switching mode of inverter through the PWM generator modulation.

As shown in Figure 4, neural net NN adopts 3 layers of forward direction BP network among Fig. 3, and the learning algorithm of network adopts neural net multivariable learning algorithm.Input layer (j) the node number that is used for the BP neural net of PI parameter tuning is 2, and input signal is deviation V _e(k) and deviation increment Delta V _e(k).That is: X ₁(k)=V _e(k), X ₂(K)=Δ V _e(k).Hidden layer (i) node number is 6, and output layer (l) node number is 2, respectively ratio and two parameters of integration of corresponding PI controller.ω _IjBe the link weight coefficients of input layer to hidden layer, ω _LiBe the link weight coefficients of hidden layer to output layer.Performance index function is:

$J=\frac{1}{2}[r(k+1)-y(k+1){]}^2---\left(4\right)$

In the following formula, r (k+1)=V _Ref(k+1), y (k+1)=V ₁(k+1);

Link weight coefficients ω _LiAnd ω _IjBy J their negative gradient direction (steepest descent method) is adjusted and revised.

Neural net hidden layer link weight coefficients computing formula is:

$\left\{\begin{array}{c}{\mathrm{\ω}}_{\mathrm{ij}}(k+1)={\mathrm{\ω}}_{\mathrm{ij}}\left(k\right)+\mathrm{\Δ}{\mathrm{\ω}}_{\mathrm{ij}}(k+1)\\ \mathrm{\Δ}{\mathrm{\ω}}_{\mathrm{ij}}(k+1)=\mathrm{\η}{\mathrm{\δ}}_i{X}_j\left(k\right)+\mathrm{\α\Δ}{\mathrm{\ω}}_{\mathrm{ij}}\left(k\right)\\ {\mathrm{\δ}}_i=f^{\′}\left[X_i\left(k\right)\right]\·\underset{l=0}{\overset{1}{\mathrm{\Σ}}}{\mathrm{\δ}}_l{\mathrm{\ω}}_{\mathrm{li}}\left(k\right)\end{array}\right.---\left(5\right)$

The excitation function of hidden layer neuron is: f[X _i(k)]=tanh[X _i(k)];

The link weight coefficients computing formula of neural net output layer is:

$\left\{\begin{array}{c}{\mathrm{\ω}}_{\mathrm{li}}(k+1)={\mathrm{\ω}}_{\mathrm{li}}\left(k\right)+\mathrm{\Δ}{\mathrm{\ω}}_{\mathrm{li}}(k+1)\\ \mathrm{\Δ}{\mathrm{\ω}}_{\mathrm{li}}(k+1)=\mathrm{\η}{\mathrm{\δ}}_l{X}_i\left(k\right)+\mathrm{\α\Δ}{\mathrm{\ω}}_{\mathrm{li}}\left(k\right)\\ {\mathrm{\δ}}_l=V_e(k+1)\mathrm{sgn}\left[\frac{\∂y(k+1)}{\∂u\left(k\right)}\right]\·\frac{\∂u\left(k\right)}{\∂X_l\left(k\right)}\·g^{\′}\left[X_l\right]\end{array}\right.---\left(6\right)$

I=0 in the formula, 1,3,4,5.The neuronic excitation function of output layer is $g\left[X_l\right]=\frac{1}{2}(1+\tanh [X_l\left]\right).$ η is a learning rate, and α is a smoothing factor.

Claims (2)

1. harmonic wave dynamic managing and reactive-load dynamic compensation compound control method is characterized in that, may further comprise the steps:

(1) voltage, current transformer detection of grid bus three-phase voltage u _a, u _b, u _c, three-phase current i _a, i _b, i _cStatic Var Compensator output current i _Svc, comprise TCR, MSC output current i _Tcr, i _MscStatic Var Compensator output voltage u _SvcLoad current i _L

(2) detect the voltage draw, current signal by 2 MAX125 samplings after, send into dsp controller; Calculate three-phase voltage first-harmonic effective value V by dsp controller ₁, grid side harmonic current i _Sh, load-side harmonic current i _Lh, TCR harmonic current i _Tcr

(3) calculate fundamental voltage effective value V ₁With given magnitude of voltage V _RefDifference V _e, difference draws SVC controlled quentity controlled variable admittance B after regulating through neural network tuned proportion integration differentiation PI controller _Ref, its discrete control law is shown below:

B _ref(k)＝B _ref(k-1)+k _p1[V _e(k)-V _e(k-1)]+k _i1[V _e(k)]

(4) according to B _RefCalculate TCR, MSC compensation admittance B respectively _Tcr, B _Msc, and control TCR, MSC circuits for triggering provide thyristor trigger impulse, capacitor switching level, make the idle desired value that meets of SVC compensation;

(5) calculate current i _ShWith given mains by harmonics current i _Sh ^*Difference DELTA i _Sh, to difference DELTA i _ShRegulate the compensation rate that obtains the mains by harmonics electric current; Calculate current i _LhWith give fixed load harmonic current i _Lh ^*Difference DELTA i _Lh, to difference DELTA i _LhRegulate the compensation rate that obtains the load harmonic current; Calculate current i _TcrWith given TCR harmonic current i _Tcr ^*Difference DELTA i _Tcr, to difference DELTA i _TcrRegulate the compensation rate that obtains the TCR harmonic current;

(6) compensation rate of integrated load side harmonic current and mains by harmonics electric current, TCR harmonic current, the control reference signal of active filter is:

U＝K ₁·Δi _tcr+K ₂·Δi _Lh+K ₃·i _sh

Through drawing pwm signal after the modulation of high frequency triangular carrier, the break-make of control Active Power Filter-APF switching device IGBT is carried out the comprehensive regulation to harmonic wave;

(7) repeat above step, up to reaching idle compensation target.

2. cooperation control device of realizing the described control method of claim 1 based on resonance injection type hybrid active electric filter HAPF and Static Var Compensator SVC, comprise main device and control device, it is characterized in that main device comprises the Static Var Compensator SVC that resonance injection type hybrid active electric filter HAPF, the thyristor-controlled reactor TCR that is connected with triangle by the mechanical type opening-closing capacitor bank MSC of star-like connection form; Active Power Filter-APF is connected in parallel by coupling transformer and first-harmonic resonance circuit behind the LC filter filtering, again through injecting capacitor C _GInsert electrical network; Every phase thyristor-controlled reactor is in series by the air core reactor of an antiparallel a pair of thyristor and a linearity and forms, and three-phase thyristor control reactor is connected into during △ shape is connected to the grid; Three-phase mechanical type switched capacitor is connected into Y shape, in being connected to the grid by controlled mechanical switch; Control device comprises the voltage that inserts sampling module, current transformer, the output of described sampling module inserts dsp controller, wherein there is industrial computer to be connected by communication module and dsp controller are two-way, the output of dsp controller inserts the MSC logic control circuit respectively, TCR admittance-angle calculation module, pwm signal generation module, MSC logic control circuit wherein, TCR admittance-angle calculation module is respectively by the MSC circuits for triggering, TCR circuits for triggering and pwm signal generation module together connect the light inputting end transmitter, insert light end receiver by optical fiber again, light end receiver is by isolating and power amplification circuit inserts MSC in the main device respectively, TCR and HAPF.

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