CN102769301B - Voltage control method for wind farm wind turbine-side voltage in dangerous state - Google Patents

Abstract

The invention relates to a voltage control method for wind farm wind turbine-side voltage in a dangerous state, belonging to the technical field of automatic voltage control of a power system. Firstly, two states of wind turbine-side voltage and two states of wind farm synchronization point voltage are defined. When the wind turbine-side voltage is in the dangerous state, a voltage emergency control method is adopted to control wind turbines and static reactive compensation devices in the wind farm, and reactive power of static var generators controls the wind turbine-side voltage to a safe state. The method can be integrated in an automatic voltage control system which operates in the field of the wind farm to enable the automatic voltage control system to monitor the voltage states of the wind turbines in real time, execute corresponding control strategies and guarantee the safety of the wind turbine-side voltage.

Description

A kind of wind electric field blower set end voltage voltage control method in the hole

Technical field

The present invention relates to a kind of wind electric field blower set end voltage voltage control method in the hole, belong to electric power system automatism voltage control technical field.

Background technology

Again and again there is in recent years wind energy turbine set inner blower because of voltage problem off-grid, and in wind energy turbine set, set up the effective means that automatic voltage control system is considered to solve wind energy turbine set voltage problem.Wind energy turbine set automatism voltage control, is the blower fan utilizing in wind energy turbine set, static passive compensation device, and static state reactive generator, waits equipment to complete the safety-optimized control of reactive voltage in wind energy turbine set.But be different from extreme misery power plant, wind energy turbine set has a plurality of control targets in voltage control: in wind energy turbine set, automatic voltage control system has not only needed that control centre issues to the control target of wind farm grid-connected point voltage (being generally wind energy turbine set booster stations high voltage bus voltage), more to guarantee that a set end voltage of interior different local wind turbines is all in safe range, and the set end voltage safe operation scope of the most of blower fan of current China is rated voltage ± 10%, compare Hydro-Thermal Systems unit, more harsh to the requirement of voltage.And because wind energy turbine set has network characteristics, guaranteeing on the basis that the whole network voltage is qualified, also will guarantee that the reactive power distribution of electric power networks in wind energy turbine set is reasonable.

But automatic voltage control system in existing wind energy turbine set, often only take wind farm grid-connected point voltage as controlling target, lacks the control to blower fan set end voltage.

In control method described herein, relate to the concept of voltage perunit value, He Yangzan, Wen Zengyin is in < < power system analysis (first volume) > > (publishing house of the Central China University of Science and Technology in January, 2002, the third edition, pp.3543) mention, mark the one system is a kind of of relative unit system, and in mark the one system, each physical quantity all represents with perunit value.Perunit value definition is provided by following formula.

For example the famous value of the reality of blower fan set end voltage is 690V, and selected its voltage reference value is its load voltage value 690V, and according to formula (1), the perunit value of known this blower fan set end voltage is 690/690=1.

In wind energy turbine set voltage control process, can use the sensitivity of reactive power to voltage, reactive power is for characterizing the linear relationship between reactive power and voltage to the sensitivity of voltage.If the reactive power variable quantity of node A is the voltage variety of Node B is the sensitivity of the reactive power of node A to Node B voltage definition can be provided by following formula:

$S_A^B=\frac{\&PartialD;V}{\&PartialD;Q}---\left(2\right)$

In wind energy turbine set, all internodal reactive powers can form the sensitivity matrix of reactive power to voltage to the sensitivity of voltage, the circular of reactive power to the sensitivity matrix of voltage, can be referring to Sun Hongbin, Zhang Baiming, Xiang Niande is at the analytical method > > of < < new sensitivity (Proceedings of the CSEE, in April, 1999 V19N4, pp.9-13).

Summary of the invention

The object of the invention is to propose a kind of wind electric field blower set end voltage voltage control method in the hole, to overcome the deficiencies in the prior art part, make the voltage status that the automatic voltage control system of wind energy turbine set can real time monitoring blower fan, implement corresponding control strategy, to ensure wind electric field blower set end voltage safety.

The wind electric field blower set end voltage voltage control method in the hole that the present invention proposes, comprises the following steps:

(1) establishing the perunit value of each blower fan set end voltage value in wind energy turbine set is V _g, the perunit value of the secure reference value of blower fan set end voltage value is if η is a judgment value, and 0< η <0.1, the voltage status of each blower fan in wind energy turbine set is judged, if blower fan set end voltage is in a safe condition, if blower fan set end voltage is in the hole, if all blower fan set end voltages are all in a safe condition, repeats this step, if there is one or more blower fan set end voltage in the hole, carries out step (2);

(2) actual value of establishing the grid-connected point voltage that wind energy turbine set is connected to the grid is the grid-connected point voltage that grid dispatching center issues is controlled desired value if the qualified threshold value of grid-connected point voltage is V _dead, the grid-connected point voltage state that wind energy turbine set is connected to the grid judges, if wind farm grid-connected point voltage is in normal condition, if wind farm grid-connected point voltage is in tracking state;

(3) reactive power of establishing wind electric field blower to the mean value of blower fan set end voltage sensitivity is if have the set end voltage of t Fans in the hole in the n Fans of wind energy turbine set, the current reactive power of the r Fans in t Fans is Q _{wtg, r}, higher limit and the lower limit of reactive power are respectively with the perunit value of r Fans set end voltage value is V _g,r, by the reactive power currency Q of set end voltage blower fan in the hole _{wtg, r}be adjusted into Reactive Power Control desired value $Q_{\mathrm{wtg},r}^{\mathrm{set}}=Q_{\mathrm{wtg},r}+\frac{V_G^{\mathrm{Ref}}-V_{G,r}}{S_{\mathrm{wtg}}^{\mathrm{wtg}}};$

(4) carry out judging:

If (4-1), in the interior blower fan in the hole of wind energy turbine set, the set end voltage of part blower fan is higher than the perunit value of the secure reference value of blower fan set end voltage value the set end voltage of part blower fan lower than send alarm signal, complete control;

If (4-2) wind farm grid-connected point voltage is normal condition, or wind farm grid-connected point voltage is tracking state, and grid-connected point voltage controlling party is to the voltage control opposite direction with set end voltage blower fan in the hole, sends alarm signal, completes control;

If (4-3) wind farm grid-connected point voltage is tracking state, and grid-connected point voltage controlling party is identical to the voltage control direction of the blower fan in the hole with set end voltage, carries out step (5);

(5) establishing the reactive power of every Fans in wind energy turbine set to the mean value of the sensitivity of wind farm grid-connected point voltage is sensitivity amplification coefficient is N ₁, N ₁value be the integer between 1-8, every static passive compensation device or static state reactive generator to the mean value of the sensitivity of wind farm grid-connected point voltage are sensitivity amplification coefficient is N ₂, N ₂value be the integer between 1-8, if wind energy turbine set has p platform static passive compensation device or static state reactive generator, in n Fans, have the set end voltage of s Fans in normal condition, in the blower fan of s platform set end voltage in normal condition, the current reactive power of i Fans is Q _{wtg, i}, reactive power higher limit and the lower limit of i Fans are respectively with the reactive power of the j platform in p platform static passive compensation device or static state reactive generator is Q _{svc, j}, higher limit and the lower limit of j platform static passive compensation device or static state reactive generator reactive power are respectively with if the Reactive Power Control desired value of i Fans is the Reactive Power Control desired value of j platform static passive compensation device or static state reactive generator is

If by s platform set end voltage, the reactive power currency of the blower fan in normal condition is adjusted into Reactive Power Control desired value respectively $Q_{\mathrm{wtg},i}^{\mathrm{set}}=Q_{\mathrm{wtg},i}+\frac{V_w^{\mathrm{Ref}}-V_w^{\mathrm{Real}}}{S_{\mathrm{wtg}}^{\mathrm{poc}}\&times;N_1}\&times;\frac{Q_{\mathrm{wtg},i}^{\mathrm{UpLmt}}-Q_{\mathrm{wtg},i}}{\underset{i=1}{\overset{s}{\mathrm{\&Sigma;}}}(Q_{\mathrm{wtg},i}^{\mathrm{UpLmt}}-Q_{\mathrm{wtg},i})},$

And respectively the reactive power currency of p platform static passive compensation device or static state reactive generator is adjusted into Reactive Power Control desired value $Q_{\mathrm{svc},j}^{\mathrm{set}}=Q_{\mathrm{svc},j}+\frac{V_w^{\mathrm{Ref}}-V_w^{\mathrm{Real}}}{S_{\mathrm{svc}}^{\mathrm{poc}}\&times;N_2}\&times;\frac{Q_{\mathrm{svc},j}^{\mathrm{UpLmt}}-Q_{\mathrm{svc},j}}{\underset{j=1}{\overset{p}{\mathrm{\&Sigma;}}}(Q_{\mathrm{svc},j}^{\mathrm{UpLmt}}-Q_{\mathrm{svc},j})},$

If by s platform set end voltage, the reactive power currency of the blower fan in normal condition is adjusted into Reactive Power Control desired value respectively $Q_{\mathrm{wtg},i}^{\mathrm{set}}=Q_{\mathrm{wtg},i}+\frac{V_w^{\mathrm{Ref}}-V_w^{\mathrm{Real}}}{S_{\mathrm{wtg}}^{\mathrm{poc}}\&times;N_1}\&times;\frac{{Q_{\mathrm{wtg},i}-Q}_{\mathrm{wtg},i}^{\mathrm{DownLmt}}}{\underset{i=1}{\overset{s}{\mathrm{\&Sigma;}}}(Q_{\mathrm{wtg},i}-Q_{\mathrm{wtg},i}^{\mathrm{DownLmt}})},$

And respectively the reactive power currency of p platform static passive compensation device or static state reactive generator is adjusted into Reactive Power Control desired value $Q_{\mathrm{svc},j}^{\mathrm{set}}=Q_{\mathrm{svc},j}+\frac{V_w^{\mathrm{Ref}}-V_w^{\mathrm{Real}}}{S_{\mathrm{svc}}^{\mathrm{poc}}\&times;N_2}\&times;\frac{{Q_{\mathrm{svc},j}-Q}_{\mathrm{svc},j}^{\mathrm{DownLmt}}}{\underset{j=1}{\overset{s}{\mathrm{\&Sigma;}}}(Q_{\mathrm{svc},j}-Q_{\mathrm{svc},j}^{\mathrm{DownLmt}})}.$

The wind electric field blower set end voltage voltage control method in the hole that the present invention proposes, its feature and effect are, the two states of blower fan set end voltage and the two states of wind farm grid-connected point voltage in the inventive method, have been defined, propose when blower fan set end voltage is in the hole, take Voltage Emergency Control method, control blower fan and static passive compensation device in wind energy turbine set, the reactive power of static state reactive generator, returns the control of blower fan set end voltage to safe condition.Than voltage control method in traditional wind energy turbine set of not considering blower fan set end voltage, more can provide safety guarantee for blower fan set end voltage.The inventive method, can be integrated in the automatic voltage control system of the on-the-spot operation of wind energy turbine set, makes the voltage status that this system can real time monitoring blower fan, implements corresponding control strategy, ensures blower fan set end voltage safety.

Accompanying drawing explanation

Fig. 1 is the wind energy turbine set electric power networks schematic diagram that uses the inventive method.

Embodiment

The wind electric field blower set end voltage voltage control method in the hole that the present invention proposes, as shown in Figure 1, the method comprises the following steps the electric power networks schematic diagram of wind energy turbine set wherein:

(1) establishing the perunit value of each blower fan set end voltage value in wind energy turbine set is V _g, the perunit value of the secure reference value of blower fan set end voltage value is if η is a judgment value, and 0< η <0.1, the voltage status of each blower fan in wind energy turbine set is judged, if blower fan set end voltage is in a safe condition, if blower fan set end voltage is in the hole, if all blower fan set end voltages are all in a safe condition, repeats this step, if there is one or more blower fan set end voltage in the hole, carries out step (2);

(2) actual value of establishing the grid-connected point voltage that wind energy turbine set is connected to the grid is the grid-connected point voltage that grid dispatching center issues is controlled desired value the controlling party that this desired value has represented wind farm grid-connected point voltage to, the qualified threshold value of establishing grid-connected point voltage is V _dead, the grid-connected point voltage state that wind energy turbine set is connected to the grid judges, if wind farm grid-connected point voltage is in normal condition, if wind farm grid-connected point voltage is in tracking state;

(3) adopt the new sensitivity computational methods of introducing in above background technology, according to network model in wind energy turbine set and on-the-spot electric metric data, can calculate the sensitivity matrix of all internodal reactive powers to voltage in wind energy turbine set, then from this sensitivity matrix, obtain the reactive power of every Fans in wind energy turbine set to the sensitivity of set end voltage separately, the mean value that calculates these sensitivity, is designated as if have the set end voltage of t Fans in the hole in the n Fans of wind energy turbine set, the current reactive power of the r Fans in t Fans is Q _{wtg, r}, higher limit and the lower limit of reactive power are respectively with the perunit value of r Fans set end voltage value is V _{g, r}, by the reactive power currency Q of set end voltage blower fan in the hole _{wtg, r}be adjusted into Reactive Power Control desired value

(4) carry out judging:

If (4-1), in the interior blower fan in the hole of wind energy turbine set, the set end voltage of part blower fan is higher than the perunit value of the secure reference value of blower fan set end voltage value the set end voltage of part blower fan lower than for example send " may there is mistake in the electric measurement of wind energy turbine set, or the no-load voltage ratio of the box type transformer of blower fan may arrange unreasonable " alarm signal, complete control;

If (4-2) wind farm grid-connected point voltage is normal condition, or wind farm grid-connected point voltage is tracking state, and grid-connected point voltage controlling party is to the voltage control opposite direction with set end voltage blower fan in the hole, send for example alarm signal of " it is unreasonable that wind farm grid-connected point voltage is controlled desired value ", complete control;

If (4-3) wind farm grid-connected point voltage is tracking state, and grid-connected point voltage controlling party is identical to the voltage control direction of the blower fan in the hole with set end voltage, carries out step (5);

(5) control object of this step is an interior static passive compensation device SVC(Static Var Compensator), static state reactive generator SVG(Static Var Generator) and the blower fan of set end voltage in normal condition.Controlling target is to follow wind farm grid-connected point voltage to control desired value thereby also can help set end voltage blower fan in the hole to get back to safe condition.The same new sensitivity computational methods of introducing in above background technology that adopt, according to network model in wind energy turbine set and on-the-spot electric metric data, calculate the sensitivity matrix of all internodal reactive powers to voltage in wind energy turbine set, then from this sensitivity matrix, obtain the sensitivity of the reactive power of every Fans in wind energy turbine set to wind farm grid-connected point voltage, the mean value of meter sensitivity, is designated as if corresponding sensitivity amplification coefficient is N ₁, N ₁value be the integer between 1-8, according to similar approach, calculate every static passive compensation device or the mean value of static state reactive generator to the sensitivity of wind farm grid-connected point voltage, be designated as corresponding sensitivity amplification coefficient is N ₂, N ₂value be the integer between 1-8, if wind energy turbine set has p platform static passive compensation device or static state reactive generator, in n Fans, have the set end voltage of s Fans in normal condition, in the blower fan of s platform set end voltage in normal condition, the current reactive power of i Fans is Q _{wtg, i}, reactive power higher limit and the lower limit of i Fans are respectively with the reactive power of the j platform in p platform static passive compensation device or static state reactive generator is Q _{svc, j}, higher limit and the lower limit of j platform static passive compensation device or static state reactive generator reactive power are respectively with if the Reactive Power Control desired value of i Fans is the Reactive Power Control desired value of j platform static passive compensation device or static state reactive generator is

If by s platform set end voltage, the reactive power currency of the blower fan in normal condition is adjusted into Reactive Power Control desired value respectively $Q_{\mathrm{wtg},i}^{\mathrm{set}}=Q_{\mathrm{wtg},i}+\frac{V_w^{\mathrm{Ref}}-V_w^{\mathrm{Real}}}{S_{\mathrm{wtg}}^{\mathrm{poc}}\&times;N_1}\&times;\frac{Q_{\mathrm{wtg},i}^{\mathrm{UpLmt}}-Q_{\mathrm{wtg},i}}{\underset{i=1}{\overset{s}{\mathrm{\&Sigma;}}}(Q_{\mathrm{wtg},i}^{\mathrm{UpLmt}}-Q_{\mathrm{wtg},i})},$

And respectively the reactive power currency of p platform static passive compensation device or static state reactive generator is adjusted into Reactive Power Control desired value $Q_{\mathrm{svc},j}^{\mathrm{set}}=Q_{\mathrm{svc},j}+\frac{V_w^{\mathrm{Ref}}-V_w^{\mathrm{Real}}}{S_{\mathrm{svc}}^{\mathrm{poc}}\&times;N_2}\&times;\frac{Q_{\mathrm{svc},j}^{\mathrm{UpLmt}}-Q_{\mathrm{svc},j}}{\underset{j=1}{\overset{p}{\mathrm{\&Sigma;}}}(Q_{\mathrm{svc},j}^{\mathrm{UpLmt}}-Q_{\mathrm{svc},j})},$

If by s platform set end voltage, the reactive power currency of the blower fan in normal condition is adjusted into Reactive Power Control desired value respectively $Q_{\mathrm{wtg},i}^{\mathrm{set}}=Q_{\mathrm{wtg},i}+\frac{V_w^{\mathrm{Ref}}-V_w^{\mathrm{Real}}}{S_{\mathrm{wtg}}^{\mathrm{poc}}\&times;N_1}\&times;\frac{{Q_{\mathrm{wtg},i}-Q}_{\mathrm{wtg},i}^{\mathrm{DownLmt}}}{\underset{i=1}{\overset{s}{\mathrm{\&Sigma;}}}(Q_{\mathrm{wtg},i}-Q_{\mathrm{wtg},i}^{\mathrm{DownLmt}})},$

And respectively the reactive power currency of p platform static passive compensation device or static state reactive generator is adjusted into Reactive Power Control desired value $Q_{\mathrm{svc},j}^{\mathrm{set}}=Q_{\mathrm{svc},j}+\frac{V_w^{\mathrm{Ref}}-V_w^{\mathrm{Real}}}{S_{\mathrm{svc}}^{\mathrm{poc}}\&times;N_2}\&times;\frac{{Q_{\mathrm{svc},j}-Q}_{\mathrm{svc},j}^{\mathrm{DownLmt}}}{\underset{j=1}{\overset{s}{\mathrm{\&Sigma;}}}(Q_{\mathrm{svc},j}-Q_{\mathrm{svc},j}^{\mathrm{DownLmt}})}.$

Claims (1)

1. a wind electric field blower set end voltage voltage control method in the hole, is characterized in that the method comprises the following steps:

(1) establishing the perunit value of each blower fan set end voltage value in wind energy turbine set is V _g, the perunit value of the secure reference value of blower fan set end voltage value is if η is a judgment value, and 0< η <0.1, the voltage status of each blower fan in wind energy turbine set is judged, if blower fan set end voltage is in a safe condition, if blower fan set end voltage is in the hole, if all blower fan set end voltages are all in a safe condition, repeats this step, if there is one or more blower fan set end voltage in the hole, carries out step (2);

(2) actual value of establishing the grid-connected point voltage that wind energy turbine set is connected to the grid is the grid-connected point voltage that grid dispatching center issues is controlled desired value if the qualified threshold value of grid-connected point voltage is V _dead, the grid-connected point voltage state that wind energy turbine set is connected to the grid judges, if wind farm grid-connected point voltage is in normal condition, if wind farm grid-connected point voltage is in tracking state;

(3) reactive power of establishing wind electric field blower to the mean value of blower fan set end voltage sensitivity is if have the set end voltage of t Fans in the hole in the n Fans of wind energy turbine set, the current reactive power of the r Fans in t Fans is Q _{wtg, r}, higher limit and the lower limit of reactive power are respectively with the perunit value of r Fans set end voltage value is V _{g, r}, by the reactive power currency Q of set end voltage blower fan in the hole _{wtg, r}be adjusted into Reactive Power Control desired value

(4) carry out judging:

If (4-1), in the interior blower fan in the hole of wind energy turbine set, the set end voltage of part blower fan is higher than the perunit value of the secure reference value of blower fan set end voltage value the set end voltage of part blower fan lower than send alarm signal, complete control;

If (4-2) wind farm grid-connected point voltage is normal condition, or wind farm grid-connected point voltage is tracking state, and grid-connected point voltage controlling party is to the voltage control opposite direction with set end voltage blower fan in the hole, sends alarm signal, completes control;

If (4-3) wind farm grid-connected point voltage is tracking state, and grid-connected point voltage controlling party is identical to the voltage control direction of the blower fan in the hole with set end voltage, carries out step (5);

(5) establishing the reactive power of every Fans in wind energy turbine set to the mean value of the sensitivity of wind farm grid-connected point voltage is sensitivity amplification coefficient is N ₁, N ₁value be the integer between 1-8, every static passive compensation device or static state reactive generator to the mean value of the sensitivity of wind farm grid-connected point voltage are sensitivity amplification coefficient is N ₂, N ₂value be the integer between 1-8, if wind energy turbine set has p platform static passive compensation device or static state reactive generator, in n Fans, have the set end voltage of s Fans in normal condition, in the blower fan of s platform set end voltage in normal condition, the current reactive power of i Fans is Q _{wtg, i}, reactive power higher limit and the lower limit of i Fans are respectively with the reactive power of the j platform in p platform static passive compensation device or static state reactive generator is Q _{svc, j}, higher limit and the lower limit of j platform static passive compensation device or static state reactive generator reactive power are respectively with if the Reactive Power Control desired value of i Fans is the Reactive Power Control desired value of j platform static passive compensation device or static state reactive generator is

If by s platform set end voltage, the reactive power currency of the blower fan in normal condition is adjusted into Reactive Power Control desired value respectively $Q_{\mathrm{wtg},i}^{\mathrm{set}}=Q_{\mathrm{wtg},i}+\frac{V_w^{\mathrm{Ref}}-V_w^{\mathrm{Real}}}{S_{\mathrm{wtg}}^{\mathrm{poc}}\&times;N_1}\&times;\frac{Q_{\mathrm{wtg},i}^{\mathrm{UpLmt}}-Q_{\mathrm{wtg},i}}{\underset{i=1}{\overset{s}{\mathrm{\&Sigma;}}}(Q_{\mathrm{wtg},i}^{\mathrm{UpLmt}}-Q_{\mathrm{wtg},i})},$

And respectively the reactive power currency of p platform static passive compensation device or static state reactive generator is adjusted into Reactive Power Control desired value $Q_{\mathrm{svc},j}^{\mathrm{set}}=Q_{\mathrm{svc},j}+\frac{V_w^{\mathrm{Ref}}-V_w^{\mathrm{Real}}}{S_{\mathrm{svc}}^{\mathrm{poc}}\&times;N_2}\&times;\frac{Q_{\mathrm{svc},j}^{\mathrm{UpLmt}}-Q_{\mathrm{svc},j}}{\underset{j=1}{\overset{p}{\mathrm{\&Sigma;}}}(Q_{\mathrm{svc},j}^{\mathrm{UpLmt}}-Q_{\mathrm{svc},j})},$

If by s platform set end voltage, the reactive power currency of the blower fan in normal condition is adjusted into Reactive Power Control desired value respectively $Q_{\mathrm{wtg},i}^{\mathrm{set}}=Q_{\mathrm{wtg},i}+\frac{V_w^{\mathrm{Ref}}-V_w^{\mathrm{Real}}}{S_{\mathrm{wtg}}^{\mathrm{poc}}\&times;N_1}\&times;\frac{{Q_{\mathrm{wtg},i}-Q}_{\mathrm{wtg},i}^{\mathrm{DownLmt}}}{\underset{i=1}{\overset{s}{\mathrm{\&Sigma;}}}(Q_{\mathrm{wtg},i}-Q_{\mathrm{wtg},i}^{\mathrm{DownLmt}})},$

And respectively the reactive power currency of p platform static passive compensation device or static state reactive generator is adjusted into Reactive Power Control desired value $Q_{\mathrm{svc},j}^{\mathrm{set}}=Q_{\mathrm{svc},j}+\frac{V_w^{\mathrm{Ref}}-V_w^{\mathrm{Real}}}{S_{\mathrm{svc}}^{\mathrm{poc}}\&times;N_2}\&times;\frac{{Q_{\mathrm{svc},j}-Q}_{\mathrm{svc},j}^{\mathrm{DownLmt}}}{\underset{j=1}{\overset{s}{\mathrm{\&Sigma;}}}(Q_{\mathrm{svc},j}-Q_{\mathrm{svc},j}^{\mathrm{DownLmt}})}.$