CN110912156B - Method and device for inhibiting doubly-fed fan subsynchronous resonance - Google Patents
Method and device for inhibiting doubly-fed fan subsynchronous resonance Download PDFInfo
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- CN110912156B CN110912156B CN201911233483.9A CN201911233483A CN110912156B CN 110912156 B CN110912156 B CN 110912156B CN 201911233483 A CN201911233483 A CN 201911233483A CN 110912156 B CN110912156 B CN 110912156B
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- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02J—CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY
- H02J3/00—Circuit arrangements for ac mains or ac distribution networks
- H02J3/24—Arrangements for preventing or reducing oscillations of power in networks
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- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02J—CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY
- H02J3/00—Circuit arrangements for ac mains or ac distribution networks
- H02J3/38—Arrangements for parallely feeding a single network by two or more generators, converters or transformers
- H02J3/40—Synchronising a generator for connection to a network or to another generator
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- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02P—CONTROL OR REGULATION OF ELECTRIC MOTORS, ELECTRIC GENERATORS OR DYNAMO-ELECTRIC CONVERTERS; CONTROLLING TRANSFORMERS, REACTORS OR CHOKE COILS
- H02P21/00—Arrangements or methods for the control of electric machines by vector control, e.g. by control of field orientation
- H02P21/24—Vector control not involving the use of rotor position or rotor speed sensors
- H02P21/28—Stator flux based control
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Abstract
The invention discloses a method and a device for inhibiting the subsynchronous resonance of a doubly-fed fan. The method comprises the following steps: acquiring an initial electric signal of a subsynchronous damping control loop; determining a compensation signal of a subsynchronous damping control loop according to the subsynchronous angular frequency reference value; the subsynchronous angular frequency reference value is the root mean square of the sum of the square of the maximum value of the subsynchronous angular frequency and the square of the minimum value of the subsynchronous angular frequency; and forming a control signal of the double-fed fan converter control loop according to the initial electric signal and the compensation signal. The subsynchronous angular frequency reference value changes according to the change of the subsynchronous angular frequency maximum value and the subsynchronous angular frequency minimum value, and the corresponding compensation signal changes adaptively according to the change of the subsynchronous angular frequency reference value, so that the compensation signal can better match the subsynchronous angular frequency of subsynchronous resonance, the positive damping generated by the subsynchronous damping control loop is larger, and the capability of the subsynchronous damping control loop in inhibiting the subsynchronous resonance is improved.
Description
Technical Field
The embodiment of the invention relates to the technical field of power system control, in particular to a method and a device for inhibiting sub-synchronous resonance of a double-fed fan.
Background
Series capacitance compensation can remarkably improve the transmission capacity and transient stability of a line, and can be applied to long-distance wind power delivery, but the risk of inducing subsynchronous Resonance (SSR) also exists.
Wind farm SSR issues have received extensive attention from both academic and industrial circles. A lot of research has shown that double-fed wind power plants are more prone to SSR problems than other types of plants. The SSR instability is caused by interaction among the double-fed wind generating set, the power electronic converter control system and the series compensation transmission line. In the existing scheme, a subsynchronous damping control loop is added in a rotor-side converter control strategy to realize the suppression of subsynchronous oscillation. The subsynchronous damping control loop has larger fluctuation when the subsynchronous damping control loop has the capability of inhibiting subsynchronous oscillation corresponding to different oscillation frequencies, so that the subsynchronous damping control loop has unstable capability of inhibiting the subsynchronous oscillation and smaller application range.
Disclosure of Invention
The invention provides a method and a device for inhibiting the subsynchronous resonance of a doubly-fed fan, which are used for improving the stability of a subsynchronous damping control loop in inhibiting the subsynchronous oscillation and increasing the application range of the subsynchronous damping control loop.
In a first aspect, an embodiment of the present invention provides a method for suppressing a sub-synchronous resonance of a doubly-fed wind turbine, including:
acquiring an initial electric signal of a subsynchronous damping control loop;
determining a compensation signal of a subsynchronous damping control loop according to the subsynchronous angular frequency reference value; the subsynchronous angular frequency reference value is the root mean square of the sum of the square of the subsynchronous angular frequency maximum value and the square of the subsynchronous angular frequency minimum value;
and forming a control signal of a double-fed fan converter control loop according to the initial electric signal and the compensation signal.
Optionally, the relationship between the secondary synchronization angular frequency reference value and the compensation signal is:
wherein e isrdqK is the maximum value of the absolute values of the attenuation rates of the synchronous current of the doubly-fed fan under n divergent working conditions for compensating signals, and n is a positive integer greater than 1 or equal to 1; l ismIs the excitation inductance of the doubly-fed fan, LsStator inductance, omega, of doubly-fed wind turbines2For the subsynchronous angular frequency reference value of the doubly-fed wind turbine,
is the stator flux, omega, of a doubly-fed wind turbineresIs a rotation speed reference value, omega, of the doubly-fed wind turbinerThe rotating speed of the double-fed fan is set,
is a flux linkage reference value, omega, of the doubly-fed wind turbinesThe synchronous rotating speed of the doubly-fed wind turbine is adopted.
Optionally, acquiring an initial electrical signal variation of the subsynchronous damping control loop includes:
acquiring an electric signal of a double-fed fan converter;
superposing the electric signal and the compensated electric signal, and then carrying out proportional-integral regulation to output an intermediate electric signal;
filtering the compensated electric signal to form a filtered electric signal;
and the filtered electric signal and the intermediate electric signal are superposed to form the initial electric signal.
Optionally, the filtering the compensated electrical signal to form a filtered electrical signal includes:
filtering the compensated electric signal by adopting a band-pass filter; the characteristic angular frequency of the filter is a subsynchronous angular frequency.
Optionally, the electric signal of the doubly-fed wind turbine converter is a rotor-side current signal or a stator-side current signal.
In a second aspect, an embodiment of the present invention further provides a device for suppressing a sub-synchronous resonance of a doubly-fed wind turbine, including:
the initial electric signal acquisition unit is used for acquiring an initial electric signal of the subsynchronous damping control loop;
the compensation signal determining unit is used for determining a compensation signal of the subsynchronous damping control loop according to the subsynchronous angular frequency reference value; the subsynchronous angular frequency reference value is the root mean square of the sum of the square of the subsynchronous angular frequency maximum value and the square of the subsynchronous angular frequency minimum value;
and the control signal generating unit is used for forming a control signal of the double-fed fan converter control loop according to the initial electric signal and the compensation signal.
Optionally, the relationship between the secondary synchronization angular frequency reference value and the compensation signal is:
wherein e isrdqK is the maximum value of the absolute values of the attenuation rates of the synchronous current of the doubly-fed fan under n divergent working conditions for compensating signals, and n is a positive integer greater than 1 or equal to 1; l ismIs the excitation inductance of the doubly-fed fan, LsStator inductance, omega, of doubly-fed wind turbines2For the subsynchronous angular frequency reference value of the doubly-fed wind turbine,
is the stator flux, omega, of a doubly-fed wind turbineresIs a rotation speed reference value, omega, of the doubly-fed wind turbinerThe rotating speed of the double-fed fan is set,
being flux linkages of doubly-fed wind-turbinesReference value, ωsThe synchronous rotating speed of the doubly-fed wind turbine is adopted.
Optionally, the initial electrical signal obtaining unit includes an electrical signal obtaining unit, a first adder, a second adder, a first proportional integral control unit, and a filtering unit;
the electric signal acquisition unit is used for acquiring an electric signal of the double-fed fan converter; the first adder is used for adding the electric signal and the compensated electric signal, the first proportional integral control unit is used for carrying out proportional adjustment on the signal obtained by adding the electric signal and the compensated electric signal to form an intermediate electric signal, the filtering unit is used for filtering the compensated electric signal to form a filtered electric signal, and the second adder is used for adding the filtered electric signal and the intermediate electric signal to form the initial electric signal.
According to the technical scheme of the embodiment of the invention, the subsynchronous angular frequency reference value is set to change according to the change of the subsynchronous angular frequency maximum value and the subsynchronous angular frequency minimum value, and the corresponding compensation signal is adaptively changed according to the change of the subsynchronous angular frequency reference value, so that the compensation signal is better matched with the subsynchronous angular frequency of subsynchronous resonance, and the larger the positive damping generated by the subsynchronous damping control loop is, thereby improving the capability of the subsynchronous damping control loop in inhibiting the subsynchronous resonance. In addition, the subsynchronous angular frequency reference value can be changed according to the subsynchronous angular frequency change, so that the subsynchronous damping control loop is not limited to the subsynchronous angular frequency when having better capability of inhibiting subsynchronous resonance, and the application range of the subsynchronous damping control loop is enlarged.
Drawings
FIG. 1 is a schematic structural diagram of series compensation power transmission of a doubly-fed wind turbine;
FIG. 2 is a schematic diagram of a control circuit of a rotor-side converter;
fig. 3 is a flowchart of a method for suppressing sub-synchronous resonance of a doubly-fed wind turbine according to an embodiment of the present invention;
fig. 4 is a schematic structural diagram of an apparatus for suppressing the sub-synchronous resonance of a doubly-fed wind turbine according to an embodiment of the present invention;
fig. 5 is a schematic diagram of a doubly-fed wind turbine series compensation power transmission system according to an embodiment of the present invention.
Detailed Description
The present invention will be described in further detail with reference to the accompanying drawings and examples. It is to be understood that the specific embodiments described herein are merely illustrative of the invention and are not limiting of the invention. It should be further noted that, for the convenience of description, only some of the structures related to the present invention are shown in the drawings, not all of the structures.
Fig. 1 is a schematic structural diagram of series compensation power transmission of a doubly-fed wind turbine. As shown in fig. 1, when the operating conditions of the fans in the wind farm are not different greatly, one doubly-fed fan can be used for the whole wind farm to be equivalent. Wherein e isr，esInduced electromotive forces of the rotor and stator, respectively, ucr，ucgOutput voltages, R, of the rotor-side converter and the stator-side converter, respectivelyr，RsResistance of rotor and stator windings, R, of asynchronous machinescrAnd LcrConnecting the equivalent resistance and inductance of the reactance, R, for a Rotor Side Converter (RSC)cgAnd LcgConnecting the equivalent resistance and inductance of the reactance, T, to a stator Side converter (GSC)gBeing an equivalent step-up transformer, Rg、LgAnd CgRespectively, the equivalent resistance, the inductance and the capacitance of the series compensation power transmission system.
The double-fed fan can send power under the condition that the rotating speed of the rotor is higher than the synchronous speed and lower than the synchronous speed by controlling the rotor-side converter and the stator-side converter. The rotor-side converter and the stator-side converter are usually controlled by a double closed loop, an outer loop generates reference current according to a control target, and an inner loop (current loop) tracks the reference current to generate reference voltage and outputs the reference voltage to the excitation voltage regulator. The rotor-side converter typically employs stator voltage-oriented control. The control aim of the rotor-side converter is to keep the motor speed stable and the stator output reactive power equal to the reference value. The control target of the stator-side converter is to maintain the voltage of the direct current capacitor between the stator converter and the rotor converter to be stable, and the terminal voltage of the double-fed fan to be stable. There are many implementations of the inner loop, such as proportional integral controller (PI), cross feed forward control, and proportional resonance control. The invention selects PI control as the realization mode of the inner ring, and is also effective for other control modes.
According to the control circuit of the double-fed fan converter, a subsynchronous damping control loop can be added to the control circuit of the rotor-side converter, and a subsynchronous damping control loop can also be added to the control circuit of the stator-side converter. Fig. 2 is a schematic diagram of a control circuit of a rotor-side converter. As shown in fig. 2, the control circuit of the rotor-side converter is taken as an example for explanation, and the control circuit of the rotor-side converter is a double closed-loop control circuit including a PI control circuit and a sub-synchronous damping control circuit 110. The phase difference between the phase of the additional matrix generated by the sub-synchronous damping control loop 110 and the phase of the rotor matrix variation is between 90 degrees and 270 degrees, so that the sub-synchronous damping control loop 110 generates a positive damping effect to suppress sub-synchronous resonance. The more the phase difference between the phase of the additional matrix generated by the sub-synchronous damping control circuit 110 and the phase of the rotor matrix variation amount is close to 180 °, the greater the positive damping generated by the sub-synchronous damping control circuit 110 is, the stronger the capability of suppressing the sub-synchronous resonance is.
In addition, the subsynchronous resonance frequency is the resonance frequency of the wind driven generator and the series compensation power transmission system connected with the wind driven generator. The subsynchronous resonance frequency can be calculated according to the series compensation degree, the equivalent inductance, the equivalent capacitance and the equivalent resistance of the series compensation power transmission system. Optionally, the subsynchronous resonance frequency may also be obtained by analyzing the waveform recorded by the fault recorder. In addition, the synchronous resonance frequency can be detected by a power system synchronous Phasor Measurement Unit (PMU). The subsynchronous resonance frequency is a constant value, and the compensation signal e of the subsynchronous damping control loop 110rdqCorresponding to the sub-synchronous resonant frequency. When the sub-synchronous resonant frequency is determined, the compensation signal e of the sub-synchronous damping control loop 110rdqIs a constant value. The sub-synchronous damping control loop 110 has a good damping effect on the corresponding sub-synchronous resonant frequency. When the sub-synchronous resonant frequency is changed,compensation signal erdqWithout change, the damping suppression action of the sub-synchronous damping control circuit 110 is reduced, and the control action of the sub-synchronous damping control circuit 110 is reduced. Wherein e isrdqThe subscript r of (1) denotes a rotor, d denotes a d-axis, and q denotes a q-axis. FIG. 2 is a schematic configuration diagram illustrating an exemplary d-axis or q-axis control loop of the rotor-side converter, and when d-axis is taken as an example for explanation, erdqCompensation signal e for d axisrd。
Aiming at the problems, the invention provides a method for inhibiting the sub-synchronous resonance of a double-fed fan. Fig. 3 is a flowchart of a method for suppressing the sub-synchronous resonance of the doubly-fed wind turbine according to an embodiment of the present invention, where the present embodiment is applicable to a case where a control circuit of the rotor-side converter or a control circuit of the stator-side converter includes a sub-synchronous damping control loop, and the method may be executed by a device for suppressing the sub-synchronous resonance of the doubly-fed wind turbine, and the device may be specifically integrated in the control circuit of the rotor-side converter or the control circuit of the stator-side converter. The method specifically comprises the following steps:
s110, acquiring an initial electric signal of a subsynchronous damping control loop;
specifically, referring to fig. 2 and 3, a control circuit of the rotor-side converter will be described as an example. The control circuit of the doubly-fed wind turbine converter comprises a PI control and subsynchronous damping control loop 110. The subsynchronous damping control loop 110 includes an adder 111 and a proportional integral control 112. Wherein the signal input of the adder 111 comprises the initial electrical signal VrdqCompensating signal erdqAnd a current signal i output from the rotor-side converterrdqInput signal E obtained by conversionrdq. Initial electrical signal VrdqAccording to the current i output by the rotor-side converterrdqAnd (6) calculating. In addition, an input signal ErdqCurrent signal i output by rotor-side converterrdqEquivalent inductance L 'with rotor'rThe product of the impedances formed.
S120, determining a compensation signal of a subsynchronous damping control loop according to the subsynchronous angular frequency reference value; the subsynchronous angular frequency reference value is the root mean square of the sum of the square of the maximum value of the subsynchronous angular frequency and the square of the minimum value of the subsynchronous angular frequency;
specifically, multiple subsynchronous resonances may occur during the operation of the doubly-fed wind turbine. The historical data of the doubly-fed wind turbine comprises subsynchronous angular frequency values of subsynchronous resonance, the maximum value is selected as the maximum value of the subsynchronous angular frequency, and the minimum value is selected as the minimum value of the subsynchronous angular frequency. And determining the subsynchronous angular frequency reference value according to the root mean square of the sum of the square of the subsynchronous angular frequency maximum value and the square of the subsynchronous angular frequency minimum value. It can be seen that the subsynchronous angular frequency reference value changes according to the variation of the subsynchronous angular frequency maximum value and the subsynchronous angular frequency minimum value, and the corresponding compensation signal erdqAdaptively changing according to the variation of the reference value of the subsynchronous angular frequency so as to compensate the signal erdqThe sub-synchronous angular frequency of the sub-synchronous resonance is better matched, and the larger the positive damping generated by the sub-synchronous damping control loop 110 is, so that the capability of the sub-synchronous damping control loop 110 for restraining the sub-synchronous resonance is improved. In addition, the sub-synchronous angular frequency reference value can be changed according to the sub-synchronous angular frequency change, so that the sub-synchronous damping control loop 110 is not limited to the sub-synchronous angular frequency when having better capability of suppressing the sub-synchronous resonance, thereby increasing the application range of the sub-synchronous damping control loop 110.
And S130, forming a control signal of the doubly-fed wind turbine converter control loop according to the initial electric signal and the compensation signal.
In particular, an initial electrical signal V is obtainedrdqAnd a compensation signal erdqThen, by measuring the current i output from the rotor-side converterrdqObtaining a current signal irdqAnd then forms a control signal through the adder 111 and the proportional integral control 112 of the subsynchronous damping control loop 110. The control signal being a compensation signal erdqFor the initial electric signal VrdqThe control signal formed after compensation, and thus relative to the initial electrical signal VrdqThe directly formed signal for controlling the converter has the function of inhibiting the sub-synchronous resonance of the double-fed fan, so that the sub-synchronous resonance can be inhibited. Wherein the proportional coefficient of the proportional integral control 112 is 1/R'r，R′rIs a rotorThe proportional integral control 112 has an integral coefficient of
In which ω isbIs the reference angular frequency, i.e. ωb2 pi f, where f is 50Hz for a 50Hz system and 60Hz for a 60Hz system.
According to the technical scheme of the embodiment, the subsynchronous angular frequency reference value is set to change according to the change of the subsynchronous angular frequency maximum value and the subsynchronous angular frequency minimum value, and the corresponding compensation signal is adaptively changed according to the change of the subsynchronous angular frequency reference value, so that the compensation signal is better matched with the subsynchronous angular frequency of subsynchronous resonance, the larger the positive damping generated by the subsynchronous damping control loop is, and the capability of the subsynchronous damping control loop in inhibiting the subsynchronous resonance is improved. In addition, the subsynchronous angular frequency reference value can be changed according to the subsynchronous angular frequency change, so that the subsynchronous damping control loop is not limited to the subsynchronous angular frequency when having better capability of inhibiting subsynchronous resonance, and the application range of the subsynchronous damping control loop is enlarged.
On the basis of the technical scheme, the relation between the subsynchronous angular frequency reference value and the compensation signal is as follows:
wherein e isrdqK is the maximum value of the absolute values of the attenuation rates of the synchronous current of the doubly-fed fan under n divergent working conditions for compensating signals, and n is a positive integer greater than 1 or equal to 1; l ismIs the excitation inductance of the doubly-fed fan, LsStator inductance, omega, of doubly-fed wind turbines2For the subsynchronous angular frequency reference value of the doubly-fed wind turbine,
is the stator flux, omega, of a doubly-fed wind turbineresIs a rotation speed reference value, omega, of the doubly-fed wind turbinerThe rotating speed of the double-fed fan is set,
is a flux linkage reference value, omega, of the doubly-fed wind turbinesThe synchronous rotating speed of the doubly-fed wind turbine is adopted.
Specifically, after the doubly-fed wind turbine is determined, the synchronous speed ω of the doubly-fed wind turbine is determinedsAnd an excitation inductor LmStator inductance LsAnd stator flux linkage
All are constant values. And the rotating speed reference value omega of the doubly-fed fanresThe method is determined by a reference table of wind speed and rotating speed of the doubly-fed wind turbine, and different wind speeds correspond to different rotating speed reference values omegares. Speed of rotation omegarThe actual rotating speed of the doubly-fed wind turbine can be obtained through measurement. Flux linkage reference value
The method is determined by a reference table of wind speed, rotating speed and power grid frequency of the doubly-fed wind turbine, and different wind speed, rotating speed and power grid frequency correspond to different flux linkage reference values
In addition, the double-fed fan is under different divergence working conditions, that is, the environmental parameters where the double-fed fan is located are different from the grid-connected parameters. For example, when the wind speed of the environment where the doubly-fed wind turbine is located changes, different wind speed environments are different divergence conditions. Under different divergence working conditions, the attenuation rates of the synchronous current of the double-fed fan are different. And k is the maximum value of the absolute values of the attenuation rates of the synchronous current of the doubly-fed fan under the n divergent working conditions, namely the attenuation rates corresponding to the two divergent working conditions with the maximum synchronous current change. For example, the attenuation rate of the synchronous current of the doubly-fed wind turbine under n divergent operating conditions is y1 … … yn, and k is maximum (| y1|, … … | yn |).
As can be seen from equation (1), the compensation signal erdqWith a reference value omega of the subsynchronous angular frequency2Is positively correlated. At the same time, when the angular frequency reference value omega of the subsynchronization2When increasing, compensating signal erdqWill also increase. Thus, the compensation signal erdqCan be adaptively changed according to the variation of the reference value of the subsynchronous angular frequency, so that the compensation signal erdqThe subsynchronous angular frequency of the subsynchronous resonance is better matched, and the larger the positive damping generated by the subsynchronous damping control loop is, so that the subsynchronous resonance restraining capability of the subsynchronous damping control loop is improved.
On the basis of the technical scheme, the method for acquiring the initial electric signal variation of the subsynchronous damping control loop comprises the following steps:
acquiring an electric signal of a double-fed fan converter;
in particular, with continued reference to fig. 2, the electrical signal of the control circuit of the current transformer may be a current signal as a control target of the control circuit. FIG. 2 shows an exemplary control circuit of the rotor-side converter, whereby the electrical signal is the current i of the rotor-side converterrdq′。
Superposing the electric signal and the compensated electric signal, performing proportional-integral regulation, and outputting an intermediate electric signal;
specifically, a control circuit of the converter adopts double closed-loop control, an outer ring generates reference current according to a control target, and an inner ring (current ring) tracks the reference current to generate reference voltage and outputs the reference voltage to the excitation voltage regulator. The outer ring feeds back the compensated electric signal output by the control circuit, and the electric signal is superposed and then converted into an intermediate electric signal through the PI controller. Wherein the intermediate electrical signal may be a voltage signal.
Filtering the compensated electric signal to form a filtered electric signal;
specifically, an inner ring in a control circuit of the converter is provided with a filter, and the filter filters the compensated electric signal output by the control circuit to form a filtered electric signal.
Filtering the compensated electric signal by adopting a band-pass filter; the characteristic angular frequency of the filter is the subsynchronous angular frequency. Illustratively, the filter may be a second order band pass filter with a transfer function of:
wherein G isBP(s) is the transfer function of the second order band-pass filter, ωcIs the characteristic angular frequency, omega, of a band-pass filterc＝2πfssr，fssrIs a sub-synchronous resonant frequency; xi is the damping ratio of the band-pass filter, and the value range of xi is 0.3-0.8. Setting the characteristic frequency of a band-pass filter to 2 pi fssrTo increase the gain around the subsynchronous resonance frequency as much as possible. By setting the characteristic angular frequency of the filter as the subsynchronous angular frequency, when the subsynchronous resonant frequency changes, the frequency range of the gain of the filter changes along with the change of the subsynchronous resonant frequency, so that the filter can realize the gain to different subsynchronous resonant frequencies.
In addition, a proportion unit Rv is further arranged on an inner ring of a control circuit of the converter, and the Rv is the maximum value of the inverse of the proportion of the current value of the synchronous current attenuated by the filter to the current value before attenuation under n divergent working conditions. For example, the ratios of the current value of the synchronous current attenuated by the filter to the current value before attenuation in n divergent conditions are k 1% and … kn%, respectively, so that Rv is maximum (1/(k 1%), 1/(k 2%), …, 1/(kn%)). At this time, the filtered electric signal Vrdq′＝GBP(s)×Rv×irdqAnd Rv can be adaptively adjusted according to different divergent working conditions and subsynchronous resonance characteristics.
The filtered electrical signal is superimposed with the intermediate electrical signal to form an initial electrical signal.
In particular, the inner loop will filter the electrical signal Vrrdq' fed back and superimposed with the intermediate electrical signal to form the initial electrical signal.
It should be noted that the electrical signal of the doubly-fed wind turbine converter may be a rotor-side current signal or a stator-side current signal.
Specifically, when the control circuit of the converter is a control circuit of the rotor-side converter, the electrical signal of the doubly-fed wind turbine converter may be a rotor-side current signal, and the control circuit controls the rotor-side converter through the rotor-side current signal. Fig. 2 shows as an example that the electrical signal of the rotor-side control circuit is a rotor-side current signal. When the control circuit of the converter is the control circuit of the stator-side converter, the electric signal of the doubly-fed wind turbine converter can be a stator-side current signal, and the control circuit controls the stator-side converter through the stator-side current signal.
Fig. 4 is a schematic structural diagram of a device for suppressing the sub-synchronous resonance of the doubly-fed wind turbine according to the embodiment of the present invention. As shown in fig. 4, the apparatus includes:
an initial electrical signal obtaining unit 10, configured to obtain an initial electrical signal of the subsynchronous damping control loop;
a compensation signal determination unit 20, configured to determine a compensation signal of the subsynchronous damping control loop according to the subsynchronous angular frequency reference value; the subsynchronous angular frequency reference value is the root mean square of the sum of the square of the maximum value of the subsynchronous angular frequency and the square of the minimum value of the subsynchronous angular frequency;
and the control signal generating unit 30 is configured to form a control signal of the doubly-fed wind turbine converter control loop according to the initial electrical signal and the compensation signal.
Specifically, the initial electric signal acquisition unit 10 provides the control signal generation unit 30 with an initial signal, and the compensation signal determination unit 20 provides the control signal generation unit 30 with a compensation signal. In the device for inhibiting the sub-synchronous resonance of the doubly-fed wind turbine, the compensation signal of the sub-synchronous damping control loop in the compensation signal determination unit 20 is changed according to the change of the sub-synchronous angular frequency reference value, and the sub-synchronous angular frequency reference value is the root mean square of the sum of the square of the maximum value of the sub-synchronous angular frequency and the square of the minimum value of the sub-synchronous angular frequency, so that the compensation signal can better match the sub-synchronous angular frequency of the sub-synchronous resonance, and the larger the positive damping generated by the sub-synchronous damping control loop is, thereby improving the capability of the sub-synchronous damping control loop for inhibiting the sub-synchronous resonance. In addition, the subsynchronous angular frequency reference value can be changed according to the subsynchronous angular frequency change, so that the subsynchronous damping control loop is not limited to the subsynchronous angular frequency when having better capability of inhibiting subsynchronous resonance, and the application range of the subsynchronous damping control loop is enlarged.
Fig. 5 is a schematic diagram of a doubly-fed wind turbine series compensation power transmission system according to an embodiment of the present invention. As shown in fig. 5, the system includes an apparatus 100 for suppressing the sub-synchronous resonance of the doubly-fed wind turbine, a series compensation unit 200 and a doubly-fed wind turbine 300. The initial electric signal acquisition unit includes an electric signal acquisition unit 40, a first adder 50, a second adder 60, a first proportional-integral control unit 70, and a filtering unit 80;
the electric signal obtaining unit 40 is used for obtaining an electric signal of the doubly-fed wind turbine converter; the first adder 50 is configured to add the electrical signal and the compensated electrical signal, the first proportional integral control unit 70 is configured to perform proportional adjustment on the added signal of the electrical signal and the compensated electrical signal to form an intermediate electrical signal, the filtering unit 80 is configured to filter the compensated electrical signal to form a filtered electrical signal, and the second adder 60 is configured to add the filtered electrical signal and the intermediate electrical signal to form an initial electrical signal.
Specifically, fig. 5 exemplarily shows that the device 100 for suppressing the sub-synchronous resonance of the doubly-fed wind turbine controls the rotor-side converter. The electric signal obtaining unit 40 in the apparatus 100 for suppressing the sub-synchronous resonance of the doubly-fed wind turbine is connected to the rotor-side converter of the doubly-fed wind turbine 200, and is configured to obtain an electric signal of the rotor-side converter. When the electrical signal is a current signal, the electrical signal acquisition unit may be a current detector. The control signal generating unit 30 is connected to a control terminal of the rotor-side converter, and after an initial electrical signal is formed, the control signal generating unit 30 controls the operation of the rotor-side converter based on a control signal formed by the initial electrical signal and the compensation signal. The control signal is formed by compensating the initial electric signal by the compensation signal, so that the control signal has the function of inhibiting the sub-synchronous resonance of the doubly-fed fan relative to the signal of the control converter directly formed by the initial electric signal, and the sub-synchronous resonance can be inhibited.
It should be noted that, in other embodiments, the device 100 for suppressing the sub-synchronous resonance of the doubly-fed wind turbine controls the stator-side converter. The electric signal obtaining unit 40 in the apparatus 100 for suppressing the sub-synchronous resonance of the doubly-fed wind turbine is connected to the stator-side converter of the doubly-fed wind turbine 200, and is configured to obtain an electric signal of the stator-side converter.
Optionally, the relationship between the sub-synchronization angular frequency reference value and the compensation signal is:
wherein e isrdqK is the maximum value of the absolute values of the attenuation rates of the synchronous current of the doubly-fed fan under n divergent working conditions for compensating signals, and n is a positive integer greater than 1 or equal to 1; l ismIs the excitation inductance of the doubly-fed fan, LsStator inductance, omega, of doubly-fed wind turbines2For the subsynchronous angular frequency reference value of the doubly-fed wind turbine,
is the stator flux, omega, of a doubly-fed wind turbineresIs a rotation speed reference value, omega, of the doubly-fed wind turbinerThe rotating speed of the double-fed fan is set,
is a flux linkage reference value, omega, of the doubly-fed wind turbinesThe synchronous rotating speed of the doubly-fed wind turbine is adopted.
It is to be noted that the foregoing is only illustrative of the preferred embodiments of the present invention and the technical principles employed. It will be understood by those skilled in the art that the present invention is not limited to the particular embodiments described herein, but is capable of various obvious changes, rearrangements and substitutions as will now become apparent to those skilled in the art without departing from the scope of the invention. Therefore, although the present invention has been described in greater detail by the above embodiments, the present invention is not limited to the above embodiments, and may include other equivalent embodiments without departing from the spirit of the present invention, and the scope of the present invention is determined by the scope of the appended claims.
Claims (6)
1. A method for inhibiting the subsynchronous resonance of a doubly-fed wind turbine is characterized by comprising the following steps:
acquiring an initial electric signal of a subsynchronous damping control loop;
determining a compensation signal of a subsynchronous damping control loop according to the subsynchronous angular frequency reference value; the subsynchronous angular frequency reference value is the root mean square of the sum of the square of the subsynchronous angular frequency maximum value and the square of the subsynchronous angular frequency minimum value;
forming a control signal of a double-fed fan converter control loop according to the initial electric signal and the compensation signal;
the relationship between the subsynchronous angular frequency reference value and the compensation signal is as follows:
wherein e isrdqK is the maximum value of the absolute values of the attenuation rates of the synchronous current of the doubly-fed fan under n divergent working conditions for compensating signals, and n is a positive integer greater than 1 or equal to 1; l ismIs the excitation inductance of the doubly-fed fan, LsStator inductance, omega, of doubly-fed wind turbines2For the subsynchronous angular frequency reference value of the doubly-fed wind turbine,
is the stator flux, omega, of a doubly-fed wind turbineresIs a rotation speed reference value, omega, of the doubly-fed wind turbinerThe rotating speed of the double-fed fan is set,
is a flux linkage reference value, omega, of the doubly-fed wind turbinesThe synchronous rotating speed of the doubly-fed wind turbine is adopted.
2. The method of claim 1, wherein obtaining an initial electrical signal variation of a subsynchronous damping control loop comprises:
acquiring an electric signal of a double-fed fan converter;
superposing the electric signal and the compensated electric signal, and then carrying out proportional-integral regulation to output an intermediate electric signal;
filtering the compensated electric signal to form a filtered electric signal;
and the filtered electric signal and the intermediate electric signal are superposed to form the initial electric signal.
3. The method of claim 2, wherein filtering the compensated electrical signal to form a filtered electrical signal comprises:
filtering the compensated electric signal by adopting a band-pass filter; the characteristic angular frequency of the filter is a subsynchronous angular frequency.
4. The method according to claim 2, wherein the electrical signal of the doubly fed wind turbine converter is a rotor side current signal or a stator side current signal.
5. A device for inhibiting doubly-fed fan subsynchronous resonance is characterized by comprising:
the initial electric signal acquisition unit is used for acquiring an initial electric signal of the subsynchronous damping control loop;
the compensation signal determining unit is used for determining a compensation signal of the subsynchronous damping control loop according to the subsynchronous angular frequency reference value; the subsynchronous angular frequency reference value is the root mean square of the sum of the square of the subsynchronous angular frequency maximum value and the square of the subsynchronous angular frequency minimum value;
the control signal generating unit is used for forming a control signal of a control loop of the double-fed fan converter according to the initial electric signal and the compensation signal;
the relationship between the subsynchronous angular frequency reference value and the compensation signal is as follows:
wherein e isrdqK is the maximum value of the absolute values of the attenuation rates of the synchronous current of the doubly-fed fan under n divergent working conditions for compensating signals, and n is a positive integer greater than 1 or equal to 1; l ismIs the excitation inductance of the doubly-fed fan, LsIs a stator of a doubly-fed fanInductance, ω2For the subsynchronous angular frequency reference value of the doubly-fed wind turbine,
is the stator flux, omega, of a doubly-fed wind turbineresIs a rotation speed reference value, omega, of the doubly-fed wind turbinerThe rotating speed of the double-fed fan is set,
is a flux linkage reference value, omega, of the doubly-fed wind turbinesThe synchronous rotating speed of the doubly-fed wind turbine is adopted.
6. The device for suppressing the subsynchronous resonance of the doubly-fed wind turbine as claimed in claim 5, wherein the initial electric signal obtaining unit comprises an electric signal obtaining unit, a first adder, a second adder, a first proportional integral control unit and a filtering unit;
the electric signal acquisition unit is used for acquiring an electric signal of the double-fed fan converter; the first adder is used for adding the electric signal and the compensated electric signal, the first proportional integral control unit is used for carrying out proportional adjustment on the signal obtained by adding the electric signal and the compensated electric signal to form an intermediate electric signal, the filtering unit is used for filtering the compensated electric signal to form a filtered electric signal, and the second adder is used for adding the filtered electric signal and the intermediate electric signal to form the initial electric signal.
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Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101449444A (en) * | 2006-05-30 | 2009-06-03 | Abb研究有限公司 | A thyristor controlled series capacitor suitable for damping sub-synchronous resonance |
| CN102869515A (en) * | 2010-03-11 | 2013-01-09 | 西门子公司 | Method and system for damping subsynchronous resonant oscillations in a power system using a wind turbine |
| CN105790269A (en) * | 2016-03-10 | 2016-07-20 | 国家电网公司华北分部 | Method and device for suppressing subsynchronous resonance through doubly-fed fan stator side converter |
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| CN105071416B (en) * | 2015-08-28 | 2018-05-04 | 中国神华能源股份有限公司 | A kind of sub-synchronous oscillation restraining device and method for suppressing power grid flickering |
| CN105790270B (en) * | 2016-03-10 | 2018-04-17 | 国家电网公司华北分部 | Suppress the method and device of subsynchronous resonance by double-fed fan rotor side converter |
| CN106329571A (en) * | 2016-09-14 | 2017-01-11 | 国网河南省电力公司平顶山供电公司 | Operation control method of DFIG grid side and rotor side PWM converter |
| CN106786674B (en) * | 2017-02-07 | 2019-09-13 | 华北电力科学研究院有限责任公司 | Double-fed blower-compensated transmission system subsynchronous resonance suppressing method and device |
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| Publication number | Priority date | Publication date | Assignee | Title |
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| CN101449444A (en) * | 2006-05-30 | 2009-06-03 | Abb研究有限公司 | A thyristor controlled series capacitor suitable for damping sub-synchronous resonance |
| CN102869515A (en) * | 2010-03-11 | 2013-01-09 | 西门子公司 | Method and system for damping subsynchronous resonant oscillations in a power system using a wind turbine |
| CN105790269A (en) * | 2016-03-10 | 2016-07-20 | 国家电网公司华北分部 | Method and device for suppressing subsynchronous resonance through doubly-fed fan stator side converter |
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