CN102891499A - Space vector pulse width modulation (SVPWM) algorithm-based and digital signal processor (DSP)-controlled energy storage system capable of inhibiting wind power fluctuations - Google Patents

Abstract

The invention discloses a space vector pulse width modulation (SVPWM) algorithm-based and digital signal processor (DSP)-controlled energy storage system capable of inhibiting wind power fluctuations. The energy storage system is characterized by comprising a main circuit unit, a synchronization signal detection circuit unit and a digital signal processor (DSP) controller unit. The working method of the energy storage system comprises the following steps of: acquiring signals, compiling an algorithm, emitting pulses and storing energy. The invention has the advantages that (1) the energy storage system is simple and easy to implement; (2) active power and reactive power are controlled independently; (3) the voltage utilization rate of a pulse width modulation (PWM) converter is improved effectively; and (4) the energy storage system has high processing speed and high sensitivity.

Description

The energy-storage system of the inhibition wind power fluctuation that the DSP based on the SVPWM algorithm controls

(1) technical field:

The invention belongs to the technical field of the access of distributed energy in intelligent grid electrical network, particularly a kind of based on SVPWM(Space Vector Pulse Width Modulation---space vector pulse width modulation) algorithm DSP (Digital Signal Processor---digital signal processor) energy-storage system of the inhibition wind power fluctuation controlled.

(2) background technology:

Along with the minimizing day by day of traditional energy, formed a recent studies on focus in electric power system---distributed generation technology (Distributed Generation Technology).Distributed power generation equipment often brings a lot of problems when grid-connected, by increasing energy storage device, can reduce the wind farm grid-connected impact that the stability of a system is produced, significant to improving the quality of power supply.Wind power generation be in the world today regenerative resource develop in the generation technology of the most ripe, the on the largest scale exploitation of technology and commercialized development prospect.

But, as the batch (-type) energy, the immediate cause that wind power generation not can be the utilization of first generation electrical network is the characteristic that it can't continuous power output.At present the existing wind generator system of China, because the power that intermittence causes can't be stablized the problem of output, makes it still can't generate electricity by way of merging two or more grid systems on a large scale, can only consume on the spot or for to the less demanding place of the quality of power supply.But, two generation electrical network construction start, it is trend of the times that wind-powered electricity generation generates electricity by way of merging two or more grid systems on a large scale, therefore to wind power generation power, the research of level and smooth stable output just seems especially important.

At present, propose several different methods and solved the level and smooth of output power fluctuation of wind farm.Have and adopt the method for directly regulating the wind turbine running status to carry out level and smooth its power output, but the method is limited in one's ability to power adjustments.Also have by full blast speed scope, in conjunction with variable pitch and speed Control, carrying out level and smooth generator active power of output, but the method can not be utilized wind energy in maximum efficiency.Adopt in addition static passive compensation device in parallel to regulate reactive power fluctuation, maintain the stable of wind power generation power network access point voltage, but smoothly active power fluctuation.Energy storage technology to develop into wind power generation extensive grid-connected and improve the wind power generation performance a kind of effective way is provided, energy storage is smoothly active power fluctuation both, can regulate reactive power again, solve to a great extent randomness and the fluctuation problem of wind power generation.

(3) summary of the invention:

The object of the present invention is to provide energy-storage system and the method for the inhibition wind power fluctuation of controlling based on the SVPWM algorithm DSP, it can overcome the deficiencies in the prior art, that a kind of power that can be applied to electric power system is smoothly exported field, the batteries to store energy technology is combined with wind generating technology, can reduce the impact of output power fluctuation of wind farm on electrical network, be conducive to improve the system and method for the stability of grid connected wind power field.

Technical scheme of the present invention: a kind of energy-storage system of the inhibition wind power fluctuation of controlling based on the SVPWM algorithm DSP is characterized in that main circuit unit, synchronization signal detection circuit unit and dsp controller unit; Wherein, the input of described synchronization signal detection circuit unit gathers synchronizing voltage and the current signal in main circuit unit, and its output connects the input of dsp controller unit; The input of described dsp controller unit gathers the voltage and current signal of main circuit unit, and its output connects the input of main circuit unit.

Described main circuit unit comprises that infinitely great electrical network, three-phase alternating-current supply, three-phase transformer, filter unit, three-phase PWM current transformer and electric power storage energy-storage units form; Wherein, the output of described infinite electrical network greatly connects three-phase alternating-current supply; The output of described three-phase alternating-current supply connects the input of three-phase transformer and the input of synchronization signal detection circuit unit; The output of described three-phase transformer connects the input of filter unit and the input of dsp controller unit; The input of described three-phase PWM current transformer is connected with the input of filter unit, and its output is connected with the input of electric power storage energy-storage units.

Described three-phase PWM current transformer is to be operated in the commutation inversion state, the two-way flow of mixed energy storage system and grid side energy be can realize, can decoupling zero the active power of wind farm grid-connected rear injection electrical network and the Three-Phase Voltage PWM Converter with the IGBT unit of reactive power be controlled.

Described DSP control unit comprises capturing unit, transducer ADCIN0 and transducer ADCIN1 unit, driver element, SVPWM pulse generation unit, current Control Algorithm unit and transducer ADCIN2 unit; Wherein, the input of described capturing unit receives three-phase current and the voltage signal that synchronous signal detection unit is sent, and its output connects the input of current Control Algorithm unit; The input of described current Control Algorithm unit also is connected with the output of transducer ADCIN0 and transducer ADCIN1 unit and the output of transducer ADCI2 unit, and its output connects the input of SVPWM pulse generation unit; The input of described driver element receives the pulse signal sent from SVPWM pulse generation unit, and its output connects the IGBT unit of three-phase PWM current transformer; The input of described transducer ADCIN0 and transducer ADCIN1 unit gathers the voltage signal of three-phase transformer leading-out terminal.

It is 50ns that described DSP control unit is selected the instruction cycle of deal with data, and the TMS320F240 dsp chip of the TI company of interfaces and input/output port occurs for integrated ADC transducer, serial communication protocol, the 9 road PWM of employing parallel data processing technology.

The method of work of the energy-storage system of the inhibition wind power fluctuation that a kind of DSP based on SVPWM controls is characterized in that it is to consist of following steps:

(1) the synchronization signal detection circuit unit gathers three-phase current signal and the voltage signal in three phase network in real time, and sends it to capturing unit in the dsp controller unit, waits for that it is processed data;

(2) after the voltage and current signal that the capturing unit of dsp controller unit is sent into according to the synchronization signal detection circuit unit obtained, obtain the signal of controller ADCIN0 and controller ADCIN1 unit, the control algolithm of being write electric current by the current Control Algorithm unit simultaneously;

(3) the dsp controller unit is according to the current Control Algorithm write, output it to SVPWM pulse generation unit, make it that SVPWM pulse signal under algorithm occur, realize the Power Exchange of AC and DC side and the control of stable DC side voltage thereby make driver element control the three-phase PWM current transformer;

(4) when the power sent when wind energy turbine set is sufficient, the three-phase PWM current transformer by unnecessary energy storage in the batteries to store energy unit;

(5) when underpower that wind energy turbine set is sent, energy storage device will discharge, and the energy stored will be fed back to three phase network by the three-phase PWM current transformer, to maintain the balance of grid-connected power.

The current Control Algorithm of described step in (3) adopted the method for Feedforward Decoupling to control respectively active current and reactive current, and it comprises the following steps:

1. by coordinate transform, the Mathematical Modeling of three-phase PWM current transformer is become to the Mathematical Modeling under the d-q coordinate, three-phase VSC(Voltage Source Convertor---voltage-source type current transformer under the d-q coordinate system) Mathematical Modeling be:

$\left\{\begin{array}{c}{u}_d=L\frac{{\mathrm{di}}_d}{\mathrm{dt}}+{\mathrm{Ri}}_d-\mathrm{\ω}{\mathrm{Li}}_q+e_d\\ u_q=L\frac{{\mathrm{di}}_q}{\mathrm{dt}}+{\mathrm{Ri}}_q-\mathrm{\ω}{\mathrm{Li}}_d+e_q\end{array}\right.$ Formula (1)

Can find that by above formula the d shaft current, together with the q current coupling, can not control respectively;

2. order $\left\{\begin{array}{c}{u}_d*\left(s\right)=(K_p+\frac{K_I}{s})(i_d*-i_d)\\ u_q*\left(s\right)=(K_p+\frac{K_I}{s})(i_q*-i_q)\end{array}\right.$ Formula (2)

I wherein _d* and i _q* the given value of current value that means respectively d axle and q axle

First two of formula (1) the equal sign right side are replaced with the pi regulator shown in formula (2),

That is: order $\left\{\begin{array}{c}L\frac{{\mathrm{di}}_d}{\mathrm{dt}}+{\mathrm{Ri}}_d=u_d*\left(s\right)\\ L\frac{{\mathrm{di}}_q}{\mathrm{dt}}+{\mathrm{Ri}}_q=u_q*\left(s\right)\end{array}\right.$ ，

Can obtain $\left\{\begin{array}{c}{u}_d=e_d-\mathrm{\ω}{\mathrm{Li}}_q+(K_p+\frac{K_I}{s})(i_d*-i_d)\\ u_q=e_q-\mathrm{\ω}{\mathrm{Li}}_d+(K_p+\frac{K_I}{s})(i_q*-i_q)\end{array}\right.$ Formula (3)

3. formula (3) substitution formula (1) can be obtained

$\left\{\begin{array}{c}\frac{{\mathrm{di}}_d}{\mathrm{dt}}=\frac{1}{L}(K_p+\frac{K_I}{s})i_d*-\frac{1}{L}[R+(K_p+\frac{K_I}{s})]i_d\\ \frac{{\mathrm{di}}_q}{\mathrm{dt}}=\frac{1}{L}(K_p+\frac{K_I}{s})i_q*-\frac{1}{L}[R+(K_p+\frac{K_I}{s})]i_q\end{array}\right.$ ；

4. as can be seen from the above equation, can realize current i by the current feed-forward Uncoupling Control Based _dand i _qcontrol be independent of each other, so just can realize the meritorious and idle component of net side without coupling and independently control, realize current Control Algorithm.

Operation principle of the present invention: IGBT(Insulated Gate Bipolar Transistors---insulated gate bipolar transistor) unit as three-phase VSC(Voltage Source Converter---voltage-source type current transformer) main element, play a part to transmit AC and DC side power; Three-phase VSC(voltage-source type current transformer) have 8 kinds of on off states, three phase voltage value of every kind of state, can obtain eight basic voltage vectors U0～U7 of α β coordinate surface through coordinate transform, wherein U0, U7 are two zero vectors, as shown in Figure 3, on α β coordinate surface, the voltage vector of any rotation all can synthesize with two basic vectors adjacent between this voltage vector location these vectors.Therefore know U α *, U β * on α β coordinate surface, also just determined the command voltage vector U that current tracking is controlled ^?thereby, realize the Current Control of 3-phase power converter.For guaranteeing higher vector U ^?synthetic precision, can adopt double triangle method synthetic schemes, utilizes U ^?it is synthetic that two adjacent space vector U1, U2 of sector, place carry out double triangle, and shown in Fig. 3 is synthetic U ^?process.Be T1, T2 the action time of supposing U1, U2 in a modulation period T, zero vector U0, U7 T0 action time, and T1+T2+T0=T and zero vector are uniformly distributed on the two ends and central point of U, by figure intermediate cam geometrical relationship, are obtained

$\left\{\begin{array}{c}\frac{\mathrm{<figure-callout\; id="1"\; label="T"\; filenames="HDA00002084278000022.png"\; state="\{\{state\}\}">T</figure-callout>}1}{2T}\left|\mathrm{<figure-callout\; id="1"\; label="U"\; filenames="HDA00002084278000022.png"\; state="\{\{state\}\}">U</figure-callout>}1\right|+\frac{T2}{2T}\left|U2\right|\cos 60=\frac{1}{2}U*\cos \mathrm{\&theta;}=\mathrm{U\&alpha;}*\\ \frac{T2}{2T}\left|U2\right|\sin 60=\frac{1}{2}U*\sin \mathrm{\&theta;}=\mathrm{U\&beta;}*\end{array}\right.$ ，

Due to

, and order

,

The symmetry that method considering zero vector U0, U7 distribute, at U ^*in apply half that vector U7 and time are T0, at U ^*two ends apply vector U0, and the time is respectively 1/4th of T0.Thereby interrupt just can realizing the generation of pwm signal by the dsp software timer.

The DSP that control circuit mainly adopts the SVPWM algorithm to control carries out the control of electric current and voltage to the three-phase PWM current transformer, to realize the two-way flow of power.Synchronization signal detection circuit is mainly the capturing unit that the three-phase voltage that will collect from electrical network and three-phase current signal are delivered to DSP, in order to wait for DSP, the three-phase PWM current transformer is controlled.Drive circuit is mainly to drive signal to carry out power amplification and send switching device IGBT to the PWM of reception, to control its conducting or shutoff.

Superiority of the present invention is: 1. hardware circuit and computer programming combine, and programming is simple; 2. adopt the method for Feedforward Decoupling and two closed-loop controls to realize the independent control of active current and reactive current, and then independently control active power and reactive power; 3. adopt SVPWM algorithm PWM Algorithm can effectively improve the voltage utilization of PWM current transformer; 4. adopt the ability of the high Precision Processing data of dsp chip, than single-chip microcomputer DSP, processing speed is faster arranged, will make like this control system form good adjusting function and there is very high sensitivity.

(4) accompanying drawing explanation:

The overall structure block diagram of the energy-storage system that Fig. 1 is the related a kind of inhibition wind power fluctuation of controlling based on the SVPWM algorithm DSP of the present invention.

The structural representation of the three-phase PWM converter module in the energy-storage system that Fig. 2 is the related a kind of inhibition wind power fluctuation of controlling based on the SVPWM algorithm DSP of the present invention.

U in SVPWM in the energy-storage system that Fig. 3 is the related a kind of inhibition wind power fluctuation of controlling based on the SVPWM algorithm DSP of the present invention ^*the vector composite diagram.

Electric current algorithm feed forward decoupling control schematic diagram in dsp controller in the energy-storage system that Fig. 4 is the related a kind of inhibition wind power fluctuation of controlling based on the SVPWM algorithm DSP of the present invention.

The control schematic diagram of the three-phase PWM current transformer in the energy-storage system that Fig. 5 is the related a kind of inhibition wind power fluctuation of controlling based on the SVPWM algorithm DSP of the present invention.

The algorithm software flow chart of the dsp controller unit in the energy-storage system that Fig. 6 is the related a kind of inhibition wind power fluctuation of controlling based on the SVPWM algorithm DSP of the present invention.

The flow chart of data processing figure of the dsp controller unit in the energy-storage system that Fig. 7 is the related a kind of inhibition wind power fluctuation of controlling based on the SVPWM algorithm DSP of the present invention.

(5) embodiment:

Embodiment: a kind of energy-storage system (see figure 1) of the inhibition wind power fluctuation of controlling based on the SVPWM algorithm DSP is characterized in that main circuit unit, synchronization signal detection circuit unit and dsp controller unit; Wherein, the input of described synchronization signal detection circuit unit gathers synchronizing voltage and the current signal in main circuit unit, and its output connects the input of dsp controller unit; The input of described dsp controller unit gathers the voltage and current signal of main circuit unit, and its output connects the input of main circuit unit.

Described main circuit unit (see figure 1) comprises that infinitely great electrical network, three-phase alternating-current supply, three-phase transformer, filter unit, three-phase PWM current transformer and electric power storage energy-storage units form; Wherein, the output of described infinite electrical network greatly connects three-phase alternating-current supply; The output of described three-phase alternating-current supply connects the input of three-phase transformer and the input of synchronization signal detection circuit unit; The output of described three-phase transformer connects the input of filter unit and the input of dsp controller unit; The input of described three-phase PWM current transformer is connected with the input of filter unit, and its output is connected with the input of electric power storage energy-storage units.

Described three-phase PWM current transformer (see figure 2) is to be operated in the commutation inversion state, the two-way flow of mixed energy storage system and grid side energy be can realize, can decoupling zero the active power of wind farm grid-connected rear injection electrical network and the Three-Phase Voltage PWM Converter with the IGBT unit of reactive power be controlled.

Described DSP control unit (see figure 1) comprises capturing unit, transducer ADCIN0 and transducer ADCIN1 unit, driver element, SVPWM pulse generation unit, current Control Algorithm unit and transducer ADCIN2 unit; Wherein, the input of described capturing unit receives three-phase current and the voltage signal that synchronous signal detection unit is sent, and its output connects the input of current Control Algorithm unit; The input of described current Control Algorithm unit also is connected with the output of transducer ADCIN0 and transducer ADCIN1 unit and the output of transducer ADCI2 unit, and its output connects the input of SVPWM pulse generation unit; The input of described driver element receives the pulse signal sent from SVPWM pulse generation unit, and its output connects the IGBT unit of three-phase PWM current transformer; The input of described transducer ADCIN0 and transducer ADCIN1 unit gathers the voltage signal of three-phase transformer leading-out terminal.

It is 50ns that described DSP control unit is selected the instruction cycle of deal with data, and the TMS320F240 dsp chip of the TI company of interfaces and input/output port occurs for integrated ADC transducer, serial communication protocol, the 9 road PWM of employing parallel data processing technology.

The method of work (seeing Fig. 3, Fig. 4, Fig. 5, Fig. 6, Fig. 7) of the energy-storage system of the inhibition wind power fluctuation that a kind of DSP based on SVPWM controls is characterized in that it is to consist of following steps:

(1) the synchronization signal detection circuit unit gathers three-phase current signal and the voltage signal in three phase network in real time, and sends it to capturing unit in the dsp controller unit, waits for that it is processed data;

(2) after the voltage and current signal that the capturing unit of dsp controller unit is sent into according to the synchronization signal detection circuit unit obtained, obtain the signal of controller ADCIN0 and controller ADCIN1 unit, the control algolithm of being write electric current by the current Control Algorithm unit simultaneously;

(3) the dsp controller unit is according to the current Control Algorithm write, output it to SVPWM pulse generation unit, make it that SVPWM pulse signal under algorithm occur, realize the Power Exchange of AC and DC side and the control of stable DC side voltage thereby make driver element control the three-phase PWM current transformer;

(4) when the power sent when wind energy turbine set is sufficient, the three-phase PWM current transformer by unnecessary energy storage in the batteries to store energy unit;

(5) when underpower that wind energy turbine set is sent, energy storage device will discharge, and the energy stored will be fed back to three phase network by the three-phase PWM current transformer, to maintain the balance of grid-connected power.

The current Control Algorithm of described step in (3) adopted the method for Feedforward Decoupling to control respectively active current and reactive current, and it comprises the following steps:

1. by coordinate transform, the Mathematical Modeling of three-phase PWM current transformer is become to the Mathematical Modeling under the d-q coordinate, three-phase VSC(Voltage Source Convertor---voltage-source type current transformer under the d-q coordinate system) Mathematical Modeling be:

$\left\{\begin{array}{c}{u}_d=L\frac{{\mathrm{di}}_d}{\mathrm{dt}}+{\mathrm{Ri}}_d-\mathrm{\&omega;}{\mathrm{Li}}_q+e_d\\ u_q=L\frac{{\mathrm{di}}_q}{\mathrm{dt}}+{\mathrm{Ri}}_q-\mathrm{\&omega;}{\mathrm{Li}}_d+e_q\end{array}\right.$ Formula (1)

Can find that by above formula the d shaft current, together with the q current coupling, can not control respectively;

2. order $\left\{\begin{array}{c}{u}_d*\left(s\right)=(K_p+\frac{K_I}{s})(i_d*-i_d)\\ u_q*\left(s\right)=(K_p+\frac{K_I}{s})(i_q*-i_q)\end{array}\right.$ Formula (2)

I wherein _d* and i _q* the given value of current value that means respectively d axle and q axle

First two of formula (1) the equal sign right side are replaced with the pi regulator shown in formula (2),

That is: order $\left\{\begin{array}{c}L\frac{{\mathrm{di}}_d}{\mathrm{dt}}+{\mathrm{Ri}}_d=u_d*\left(s\right)\\ L\frac{{\mathrm{di}}_q}{\mathrm{dt}}+{\mathrm{Ri}}_q=u_q*\left(s\right)\end{array}\right.$ ?，

Can obtain $\left\{\begin{array}{c}{u}_d=e_d-\mathrm{\&omega;}{\mathrm{Li}}_q+(K_p+\frac{K_I}{s})(i_d*-i_d)\\ u_q=e_q-\mathrm{\&omega;}{\mathrm{Li}}_d+(K_p+\frac{K_I}{s})(i_q*-i_q)\end{array}\right.$ Formula (3)

3. formula (3) substitution formula (1) can be obtained

$\left\{\begin{array}{c}\frac{{\mathrm{di}}_d}{\mathrm{dt}}=\frac{1}{L}(K_p+\frac{K_I}{s})i_d*-\frac{1}{L}[R+(K_p+\frac{K_I}{s})]i_d\\ \frac{{\mathrm{di}}_q}{\mathrm{dt}}=\frac{1}{L}(K_p+\frac{K_I}{s})i_q*-\frac{1}{L}[R+(K_p+\frac{K_I}{s})]i_q\end{array}\right.$ ；

4. as can be seen from the above equation, can realize current i by the current feed-forward Uncoupling Control Based _dand i _qcontrol be independent of each other, so just can realize the meritorious and idle component of net side without coupling and independently control, realize current Control Algorithm.

Claims (7)

1. the energy-storage system of an inhibition wind power fluctuation of controlling based on the SVPWM algorithm DSP, is characterized in that main circuit unit, synchronization signal detection circuit unit and dsp controller unit; Wherein, the input of described synchronization signal detection circuit unit gathers synchronizing voltage and the current signal in main circuit unit, and its output connects the input of dsp controller unit; The input of described dsp controller unit gathers the voltage and current signal of main circuit unit, and its output connects the input of main circuit unit.

2. the energy-storage system that a kind of inhibition wind power of controlling based on the SVPWM algorithm DSP fluctuates according to claim 1, is characterized in that described main circuit unit comprises that infinitely great electrical network, three-phase alternating-current supply, three-phase transformer, filter unit, three-phase PWM current transformer and electric power storage energy-storage units form; Wherein, the output of described infinite electrical network greatly connects three-phase alternating-current supply; The output of described three-phase alternating-current supply connects the input of three-phase transformer and the input of synchronization signal detection circuit unit; The output of described three-phase transformer connects the input of filter unit and the input of dsp controller unit; The input of described three-phase PWM current transformer is connected with the input of filter unit, and its output is connected with the input of electric power storage energy-storage units.

3. the energy-storage system that a kind of inhibition wind power of controlling based on the SVPWM algorithm DSP fluctuates according to claim 2, it is characterized in that described three-phase PWM current transformer is to be operated in the commutation inversion state, the two-way flow of mixed energy storage system and grid side energy be can realize, can decoupling zero the active power of wind farm grid-connected rear injection electrical network and the Three-Phase Voltage PWM Converter with the IGBT unit of reactive power be controlled.

4. the energy-storage system that a kind of inhibition wind power of controlling based on the SVPWM algorithm DSP fluctuates according to claim 1, is characterized in that described DSP control unit comprises capturing unit, transducer ADCIN0 and transducer ADCIN1 unit, driver element, SVPWM pulse generation unit, current Control Algorithm unit and transducer ADCIN2 unit; Wherein, the input of described capturing unit receives three-phase current and the voltage signal that synchronous signal detection unit is sent, and its output connects the input of current Control Algorithm unit; The input of described current Control Algorithm unit also is connected with the output of transducer ADCIN0 and transducer ADCIN1 unit and the output of transducer ADCI2 unit, and its output connects the input of SVPWM pulse generation unit; The input of described driver element receives the pulse signal sent from SVPWM pulse generation unit, and its output connects the IGBT unit of three-phase PWM current transformer; The input of described transducer ADCIN0 and transducer ADCIN1 unit gathers the voltage signal of three-phase transformer leading-out terminal.

5. the energy-storage system that a kind of inhibition wind power of controlling based on the SVPWM algorithm DSP fluctuates according to claim 1, it is characterized in that it is 50ns that described DSP control unit is selected the instruction cycle of deal with data, and the TMS320F240 dsp chip of the TI company of interfaces and input/output port occurs in integrated ADC transducer, serial communication protocol, the 9 road PWM of employing parallel data processing technology.

6. the method for work of the energy-storage system that the inhibition wind power of the DSP control based on SVPWM fluctuates is characterized in that it is to consist of following steps:

(1) the synchronization signal detection circuit unit gathers three-phase current signal and the voltage signal in three phase network in real time, and sends it to capturing unit in the dsp controller unit, waits for that it is processed data;

(2) after the voltage and current signal that the capturing unit of dsp controller unit is sent into according to the synchronization signal detection circuit unit obtained, obtain the signal of controller ADCIN0 and controller ADCIN1 unit, the control algolithm of being write electric current by the current Control Algorithm unit simultaneously;

(3) the dsp controller unit is according to the current Control Algorithm write, output it to SVPWM pulse generation unit, make it that SVPWM pulse signal under algorithm occur, realize the Power Exchange of AC and DC side and the control of stable DC side voltage thereby make driver element control the three-phase PWM current transformer;

(4) when the power sent when wind energy turbine set is sufficient, the three-phase PWM current transformer by unnecessary energy storage in the batteries to store energy unit;

(5) when underpower that wind energy turbine set is sent, energy storage device will discharge, and the energy stored will be fed back to three phase network by the three-phase PWM current transformer, to maintain the balance of grid-connected power.

7. the method for work of the energy-storage system of the inhibition wind power fluctuation that a kind of DSP based on SVPWM controls according to claim 6, it is characterized in that the current Control Algorithm during described step is has (3) adopted the method for Feedforward Decoupling to control respectively active current and reactive current, it comprises the following steps:

1. by coordinate transform, the Mathematical Modeling of three-phase PWM current transformer is become to the Mathematical Modeling under the d-q coordinate, three-phase VSC(Voltage Source Convertor---voltage-source type current transformer under the d-q coordinate system) Mathematical Modeling be:

$\left\{\begin{array}{c}{u}_d=L\frac{{\mathrm{di}}_d}{\mathrm{dt}}+{\mathrm{Ri}}_d-\mathrm{\&omega;}{\mathrm{Li}}_q+e_d\\ u_q=L\frac{{\mathrm{di}}_q}{\mathrm{dt}}+{\mathrm{Ri}}_q-\mathrm{\&omega;}{\mathrm{Li}}_d+e_q\end{array}\right.$ Formula (1)

Can find that by above formula the d shaft current, together with the q current coupling, can not control respectively;

2. order $\left\{\begin{array}{c}{u}_d*\left(s\right)=(K_p+\frac{K_I}{s})(i_d*-i_d)\\ u_q*\left(s\right)=(K_p+\frac{K_I}{s})(i_q*-i_q)\end{array}\right.$ Formula (2)

I wherein _d* and i _q* the given value of current value that means respectively d axle and q axle

First two of formula (1) the equal sign right side are replaced with the pi regulator shown in formula (2),

That is: order $\left\{\begin{array}{c}L\frac{{\mathrm{di}}_d}{\mathrm{dt}}+{\mathrm{Ri}}_d=u_d*\left(s\right)\\ L\frac{{\mathrm{di}}_q}{\mathrm{dt}}+{\mathrm{Ri}}_q=u_q*\left(s\right)\end{array}\right.$ ?，

Can obtain $\left\{\begin{array}{c}{u}_d=e_d-\mathrm{\&omega;}{\mathrm{Li}}_q+(K_p+\frac{K_I}{s})(i_d*-i_d)\\ u_q=e_q-\mathrm{\&omega;}{\mathrm{Li}}_d+(K_p+\frac{K_I}{s})(i_q*-i_q)\end{array}\right.$ Formula (3)

3. formula (3) substitution formula (1) can be obtained

$\left\{\begin{array}{c}\frac{{\mathrm{di}}_d}{\mathrm{dt}}=\frac{1}{L}(K_p+\frac{K_I}{s})i_d*-\frac{1}{L}[R+(K_p+\frac{K_I}{s})]i_d\\ \frac{{\mathrm{di}}_q}{\mathrm{dt}}=\frac{1}{L}(K_p+\frac{K_I}{s})i_q*-\frac{1}{L}[R+(K_p+\frac{K_I}{s})]i_q\end{array}\right.$ ；

4. as can be seen from the above equation, can realize current i by the current feed-forward Uncoupling Control Based _dand i _qcontrol be independent of each other, so just can realize the meritorious and idle component of net side without coupling and independently control, realize current Control Algorithm.

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