JP2515750B2 - Wind power generator control method - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a control method for a wind turbine generator mainly based on a variable speed control operation in which the rotation speed of a wind turbine is changed according to wind speed fluctuations, and more particularly to a rotor of the wind turbine or a wind turbine generator. The present invention relates to a program control method that enables effective energy acquisition under irregular wind condition change conditions based on generator speed information.

(Prior Art) Conventionally, as wind power generators, various types of systems having an input part such as a propeller type and a Darrieus type have been known, and DC generators, synchronous generators, and induction generators have been mainly adopted as generators. Has been done.

And, in such a conventional wind power generator, a control method matched to the characteristics of the generator side adopted is used, and it cannot be said that the operating state is suitable for the characteristics of the wind turbine blades, etc. Often overwhelmed.

Among them, many of the small ones use a DC generator, but they are merely combinations of the respective elements and are not sufficiently satisfactory in terms of their structure and control.

In addition, many of those that have assumed constant rotation control use a synchronous generator, but this control method cannot consider the efficiency characteristics of the wind turbine blades, and the fluctuation of input energy is controlled by constant rotation control. Therefore, there is a problem that a large fluctuating load is applied and effective energy acquisition cannot be maintained.

In addition, many of them are based on the assumption that the system is directly connected to another power source, but use an induction machine, but in this case as well, they have the same problems as the constant rotation control method using a synchronous machine. Moreover, since the slip-torque characteristic of the induction machine has a high gain, when the pitch control of the wind turbine blade is performed, a high responsiveness of the control system is required, and the power for that is large, which is not practical. Therefore, it is necessary to use an induction generator with a large capacity, which increases the starting wind speed, and it is difficult to protect the wind turbine against gusts (gusts). Was.

On the other hand, wind power generators include those of variable speed operation in which the number of revolutions is changed according to fluctuations in wind speed, and those of constant speed operation that are premised on system interconnection and that are premised on pitch angle control of wind turbine blades. This constant rotation operation has a relatively simple operation mode setting and control algorithm, but as described above, the energy acquisition efficiency tends to decrease, and the variable load is large and the trajectory characteristics are good. However, there is a problem that the pitch angle control accuracy and responsiveness are required to be high.

Therefore, the above problems can be solved by considering the operating characteristics of each of the variable speed and constant rotation, and no matter what kind of generator is adopted, it is necessary to fundamentally change the control algorithm. It has been desired to realize a control method that can easily cope with the problem and can acquire effective energy.

(Object of the invention) The present invention meets the above-mentioned demands, and performs variable speed control by program control having a predetermined relationship with the generator output based on the rotor speed information of the wind turbine or the generator, Regardless of the type of generator, it is possible to maintain a high energy acquisition rate under irregular wind conditions and improve start-up characteristics. A method for controlling a wind turbine generator that can easily respond to changes in the design conditions of blades, towers, and other structures, is highly economical, and can easily control the pitch angle of the wind turbine blades to save power. To do.

(Structure of the Invention) The present invention relates to a control method for a wind turbine generator that performs a variable speed control operation in which the rotation speed of a wind turbine is changed according to wind speed fluctuations, and a rotation speed of a generator or a rotor of a wind turbine until a rated output range is reached. The output is maintained at a set relationship by a program controlled constant speed ratio or variable speed operation close to it, and after reaching the rated output range, the pitch angle control of the wind turbine blades allows the fluctuation of the rotational speed to fall within a predetermined allowable range. The variable speed operation is performed to keep the output constant while keeping the output constant, and the setting relationship between the rotation speed and the output by the above program control is such that the constant frequency keeps the power factor of the wind turbine large until the rotation speed approaches the rated rotation speed. The speed ratio control and the change of the rotational speed and the output in the direction of decreasing the peripheral speed ratio of the wind turbine from before the rotational speed reaches the rated rotational speed allow the fluctuation of the rotational speed to a predetermined value. It has an algorithm with load control that keeps the range.

With this control method, variable speed operation that follows the peripheral speed ratio with high energy conversion efficiency according to the characteristics of the wind turbine blade is performed without changing the basic control algorithm according to the type of generator, and a wide rotation speed range Wind energy, which is a variable input, can be stored in the inertial system of the rotor of the wind turbine, generator, etc. over a period of time, so load fluctuations can be mitigated, start-up from low wind speeds is possible, and structure design is possible. It can be easily adapted to the conditions and characteristics.

(Example) FIG. 1 shows the basic configuration of a wind turbine generator that implements the control method of the present invention.

The device includes a wind turbine 1 that converts wind energy Pw into shaft power, a power-power converter 2 that converts the shaft power into electric power, specifically, a generator and a frequency converter (converter or the like), and a wind turbine 1 It is basically configured by a control device 3 that controls the output power of the power-power converter 2 by an output command signal that is preset according to the number of revolutions. And
An output command that detects the rotor rotation speed of the wind turbine 1 by the rotation speed sensor 4 and has a preset relationship (map) between the rotation speed and the output for the program control, which can be described later, in the control device 3. The output command signal P _REF determined by the generator 5 and the output signal P of the electric energy of the power-power converter 2 detected by the output detection circuit 6 are compared.
Then, the difference signal is used as the output of the control device 3 and the operation signal is given to the power-power converter 2 by the control amplifier 8.

In particular, in the present invention, although details will be described later, by performing variable speed control or control close to it in the program control by the map, torque fluctuation due to operation at a substantially constant peripheral speed ratio or change in wind conditions is slightly reduced. By permitting the energy consumption within the range of 1, the energy is effectively stored by operating the inertial system.

The principle will be described below by taking a propeller-type wind turbine as an example.

The basic characteristic of the output from a propeller-type wind turbine is expressed by the following equation.

Output P = 1 / 2ρ v ³ πR ² Cp (1) ρ: Air density, v: Wind velocity, Cp: Power coefficient, R: Propeller radius, ω: Angular velocity power coefficient Cp = 2P / ρπR ² v ³ … (2) Peripheral speed ratio TSR = ωR / v (3) Here, in order to obtain maximum efficiency as a wind turbine, it is sufficient to perform control that always keeps the maximum value of the power coefficient Cp, which enables maximum effective acquisition of energy. Become.

The power coefficient Cp characteristic of the wind turbine has maximum points according to the pitch angle β of the wind turbine blades, and can be expressed as a function of the peripheral speed ratio TSR from the equations (2) and (3). Therefore, when the pitch angle β of the wind turbine blade is set to a certain value, the peripheral speed ratio TSR that maximizes the power coefficient Cp is determined.

Now, assuming that the peripheral speed ratio TSR at which the power coefficient Cp is maximum is μmax, μmax = ωR / v v = ωR / μmax (4) ω = 2πN / 60 (5) where N: Wind turbine speed (rpm) From equations (4) and (5), v = R / μmax · πN / 30 (6) From equations (1) and (6) P = 1 / 2PπR ² Cp max (RπN / 30μmax) ³ = 1.8 × 10 ^{− 3} ρ R ⁵ Cp max (1 / μmax ³ ) N ³ (7) From this equation (7), it is found that the output P of the wind turbine is proportional to the cube of the rotation speed N, and the rotation speed N is used as information for constant frequency rotation. It can be seen that effective energy can be obtained by controlling the speed ratio.

The characteristics of the power coefficient Cp, output P, and torque T of these wind turbines with respect to the rotational speed N are shown in FIG. In the figure, the horizontal axis represents the rotation speed N, and the vertical axis represents the power coefficient Cp (solid line), output P (chain line), and torque T (dashed line) at each wind speed v _{1 to} v ₇ .
Shows the characteristic curve of and the line P _L shows the rated load. As can be seen from the figure, the output P shows the maximum value at the rotational speed N at which the maximum value (Cp max) of the power coefficient Cp at each wind speed V _{1 to} V ₇ is obtained. Therefore, by maintaining Cp max, the output P
Has the characteristic of curve (a), and the torque T at that time has the characteristic of curve (b). That is, by keeping the power coefficient Cp at the maximum value, the level of the output P is uniquely determined by the rotation speed N of the wind turbine. In the third diagram, N _vc is cut-in speed corresponding to the cut-in wind speed for starting the power generation (v _c), N _vL is the rated rotational speed corresponding to the rated wind speed V _L of the rated output of the wind turbine is out .

Next, a basic control chart of the wind turbine generator according to the algorithm of the present method will be described with reference to FIG. In the figure, the horizontal axis indicates the wind speed v, the vertical axis indicates the output P and the rotation speed N, v _s : the starting wind speed at which the wind turbine starts rotating, v _c : the cut-in wind speed at which power generation starts, vL: the wind turbine rating Rated wind speed at which output can be obtained, v _co : Cut-out wind speed at which wind turbine operation is stopped and _{feathered to release} wind energy, P _L : Rated output as a wind power generator, N _vc : Cut-in speed, N _vL : Rated speed, N _N : No-load setting speed of wind turbine, N _N ± 10%: Control speed range controlled by pitch control, Curve P _R : Loss power, and between v _s and v _c of generator mechanical loss and transmission loss of the gear (square curve), v _c when joined the excitation loss of the generator, v _c to v _L between the excitation loss and mechanical loss, between v _L to v _co is the generator excitation loss It is a mechanical loss (almost constant).

The operation status in FIG. 3 is as follows.

Wait: between wind speed 0 to V _s does not operating the transducer without power.

Start-up: The wind energy can be used as the energy to rotate the windmill between wind speeds v _{s and} v _c .

Cut-in: The wind power generator becomes ready to start power generation and excites the generator.

Load control area: The above-described maximum output control is performed during the wind speed v _{c to} v _L. That is, the generated electric power is controlled so that the rotation speed matches the situation of each wind speed. This gives the output P
Indicates an output characteristic proportional to the cube of the wind speed (rotation speed), and maximum output control is performed at each rotation speed.

The rotation speed N rises from v _s , rises in balance with the moment of inertia of the wind turbine, and after v _c , it is operated in proportion to the wind speed. The process in which the rotation speed increases and the process in which the wind weakens and the rotation speed decreases show a hysteresis characteristic as indicated by the arrow.

Load fixing region: The output P is kept constant during the wind speeds v _{L to} v _co , the energy of the input wind is released by a mechanical pitch controller, and the rotation speed N is controlled within a fixed allowable range.

Standby: In wind conditions above wind speed v _co , the wind energy exceeds the capacity of the equipment, so the mechanical governor uses feathers to release energy and maintain the windmill in a safe state.

In FIG. 3, the solid line of the output P is for variable speed control, and the broken line is for constant rotation control. From the comparison between the two, the cut-in wind speed v _c is reduced by the variable speed control,
It can be seen that the starting characteristics are improved.

FIG. 4 is a conceptual explanatory diagram of a control mode for energy acquisition by a wind turbine and a generator. In the figure, V is the wind speed, R represents a rotor radius of the wind turbine, Omega rotor angular velocity, Omega _R is the rotor of the nominal rotational angular velocity, C _Q torque coefficient of the wind turbine, Q _R is the rotor torque, Q _G is the generator torque, P _G is the generator output, K
The gain, K _P is a proportional gain, K _I is an integral gain, S is the derivative, I is indicated inertia, basically generator so that the difference always zero rotor torque Q _R and the generator torque Q _G is Is controlled, and the generator output P _G is obtained by multiplying the rotor angular velocity Ω and the generator torque Q _G.

Incidentally, the rotor torque Q _R in relation to the torque coefficient C _Q is a function of the command pitch angle beta mu peripheral speed ratio, the above command the pitch angle beta, the rotor angular velocity Omega is larger than the rated rotational angular velocity Omega _R Sometimes a transfer function with PI control And pitch conversion motor transmission function Obtained through. Also, the generator torque Q _G is the transfer function of the generator. Obtained through.

FIG. 5 is a relational map (algorithm) between the rotor speed N and the output P, which is the basis of the program control in the method of the present invention. Based on this map, the rotor speed information (N) is used to determine the excitation side of the generator. It gives a command and controls its output. Fig. 6 shows the output power coefficient C _P and the peripheral speed ratio TSR.
2 shows a driving trajectory according to the method of the present invention in the relationship of

In FIG. 5, a region between curves a and b is a constant peripheral speed ratio control region having a cube curve in which the output power coefficient C _P of the wind turbine keeps the highest value, and here, TSR = 11 (constant). . Further, a region in which load control is performed so that the rotation speed is kept within a certain allowable range between the substantially linear b-c immediately before reaching the rated rotation speed of the rotor that outputs the rated output. It is close to rotation control. The pitch angle of the wind turbine blade is fixed to a predetermined value between a and b. After the rated speed is reached, the linear output between cd is the area where the rated output is maintained by the pitch angle control. At the rated output point c, the peripheral speed ratio TSR = 7.7 and above that the peripheral speed ratio TSR. To reduce.

Further, in FIG. 6, the operating positions of points a and b are the above curve a.
-B, the operating locus from this point to the point c corresponds to the load control range corresponding to the curve b-c, and the operating locus from the points c to d corresponds to the curve c-d. This is the pitch control area. And the said control can be performed by seeing the output signal of a generator. In the area between the points b and c as described above, the constant peripheral speed ratio control is not performed as in the case between the points a and b, and the relationship between the rotational speed and the output is changed so as to decrease the peripheral speed ratio of the wind turbine, In other words, the control is performed so that the generator output is increased while the increase in the rotation speed is limited by the increase in the load, and as described below, this reduces noise, ensures reliability, and improves economic efficiency. While satisfying the requirements, the function of the wind turbine and the generator can be utilized to the maximum limit.

FIG. 7 shows the control mode by the algorithm of the method of the present invention in the relation between the output P and the generator speed N with respect to the wind speed V. Further, FIG. 8 shows a Campbell diagram of the relationship between the rotational angular velocity Ω of the rotor and the natural vibration angular velocity. As described above, in the variable speed control, if constant speed ratio control that follows the maximum value of the power coefficient C _P to reach the rated wind speed is performed, the energy acquisition efficiency is maximized, but the number of revolutions corresponding to the rated output is Since it is considerably high, the noise is increased, the centrifugal force of the blade and the force applied to the blade supporting portion are increased, and the resonance and the like are likely to deteriorate reliability and durability. Therefore, as an actual design problem, the upper limit of the allowable rotational speed is determined by the resonance between the tower and the blades of the wind turbine rotor, and the constraint such as the limit of the rotor peripheral speed. An allowable rotational speed limit (an allowable rotational speed limit in a state where the blade has a predetermined pitch angle) is set so as to satisfy requirements such as securing. When the rotational speed allowable limit is set to be somewhat low due to these restrictions and requirements, the generator output does not rise to the rated output even if the rotational speed allowable limit is reached only by the constant peripheral speed ratio control.

It is possible to lower the natural frequency, which is a problem, by strengthening the structure of the tower and the blade side, but in that case, of course, the weight increases and the cost increases.

Therefore, according to the present invention, the seventh algorithm is used.
As shown in the figure, constant peripheral speed ratio control is performed until the generator rotational speed N reaches the predetermined rotational speed N _1, and both the rotational speed and the output increase while varying the rotational speed according to the wind speed fluctuation. After reaching ₁ , the load control (curve P ₁ ) is performed on the generator side, that is, by changing the relationship between the rotational speed and the output in the direction of decreasing the peripheral speed ratio of the wind turbine, while limiting the increase in rotational speed. The control is performed to increase the generator output. For this reason, even if the rotational speed allowable limit is set to be somewhat low due to various restrictions and requirements as described above, the generator output can be increased to the rated output by the load control. Further, after the rated output is reached, the load is fixed and the pitch angle is controlled within a predetermined allowable range. Here, the above specified speed
N1 is set to a value smaller than the optimum rotation speed N ₂ in the case of controlling the constant peripheral speed ratio, which is determined by the theoretical characteristics of the blade. The curve P ₂ is the output when constant peripheral speed ratio control is performed up to the rated output.

Further, in FIG. 8, .OMEGA.R ^* is rated rotational angular velocity based on the theoretical characteristics of the blade, ^* -10% angular velocity Omega _R and Omega _{R *} ⁺ 20% of the range (hatched portion) seen when the rotor primary natural frequency 2P of rotation speed (2P ± 20%) in mode (flapping)
However, in the range of Ω _R −10% and Ω _R + 20% of Ω _R , which is lower than Ω _R ^* , the rotor primary natural vibration mode is 2P (2P (+/- 20%) is slightly cleared. In this range, the tower's first-order natural vibration mode also clears 1P of rotation speed (± 20% is not shown).

By lowering the operating speed in this way, both the rotor and the tower can be removed from the resonance region, the design conditions are relaxed, and the problems of the weight and cost of the structure can be solved.

Even in this problem, the difference in the amount of power generation obtained from the constant peripheral speed ratio operation is extremely small as shown by the hatched portion in FIG. 7, and the decrease in efficiency does not pose a problem.

Next, a control flow chart of the pitch conversion system on the wind turbine side and a flow chart of the control system on the generator side for implementing the above algorithm are shown in FIGS. 9 and 10, respectively.
Shown in the figure. In this embodiment, the rated output P _G is set to 890 Kw, and the pitch angle β is fixed to 4 ° on the wind turbine side and the field control I as the load control is performed on the generator side until the rated output P _G is reached to reach the rated output P _G. After that, the PID control of the pitch angle, which is a variable speed control near the rated speed, is performed on the wind turbine side, and the load (output) fixed field control II is performed on the generator side. By this control, the operation locus as shown in FIG. 6 described above can be obtained.

11 and 12 show a specific configuration example of a wind turbine generator in which the above control method is implemented, and the same reference numerals are given to the parts corresponding to the basic configuration of FIG. 1 described above.

In FIG. 11, a synchronous generator SG and a forward conversion thyristor inverter 21 are used as the power-power converter 2, and the output command generator 5 in the control device 3 uses the rotor rotation speed W _r for executing the algorithm of the present invention. And a conversion circuit for the output command P _r . The output detection circuit 6 has a current / voltage detection circuit, and the control amplifier 8 is an exciting device.
In this specific example, a reverse conversion converter 22 is provided at the output of the inverter 21, and a system interconnection output is obtained via a transformer 23. Due to this system interconnection, the gate circuit 24 controls the phase of the inverter 22 while synchronizing the output signal of the output command generator 5 and the output of the transformer 23. A DC generator may be used instead of the synchronous generator SG and the converter 21.

In FIG. 12, an induction machine IG and a transistor inverter 21 are used as the power-to-power converter 2, and other configurations are the same as in FIG. In addition, 25 is a capacitor or a battery.

As described above, regardless of whether the DC machine, the synchronous machine, or the induction machine is used, the operation mainly based on the variable speed control described above can be performed by slightly changing the map pattern in the conversion circuit.

Next, the energy acquisition amount in the variable speed control that is the main subject of the operation according to the method of the present invention will be described in comparison with the case of constant rotation control.

Now, the rotor system axis moment of inertia I, the rotor angular velocity Omega, the rotor torque Q _R, when the generator load torque and Q _G, Is established. However, C _Q : Torque coefficient μ: Peripheral speed ratio β: Pitch angle P (Ω): Generator load… Characteristics in Fig. 5 V: Wind speed R: Rotor radius ρ: Air density PI for pitch control and _{controls, β = β O + K P} (Ω-Ω R) + KI∫ (Ω-Ω R) dt is established. However, β: Pitch angle β _O : Initial pitch angle (rated pitch) Ω _R : Rotor rated angular velocity K _P : Proportional gain K _I : Integral gain Here, the gain of variable speed control by simulation is the gust in the operating wind speed range. When responding to a factor (GF) of 1.5, K _P = 9.0 K _I = 0.7, which is based on the condition that the rotation speed is allowed up to the rated ± 20%, while the gain of constant rotation control is based on the assumed wind conditions. K _P = 500 K _I = 0.7 based on the condition that the rotation speed is allowed up to the rated ± 0.5%. Now, the wind conditions are rated wind speed 13m, amplitude ± 4m / s, cycle 1
Assuming that the variable speed change is 0 sec, the wind speed is V = 13 + 4sin 2πt / 10 (m / s), and the simulation results of rotor speed, rotor output, and acquired power generation amount are shown in FIGS. 13, 14, and 15, respectively. It will be as shown in the figure. From FIG. 15, it can be seen that in the case of variable speed operation, the acquired power generation amount increases in 100 seconds as compared with the case of constant rotation operation by about 15%.

Next, the fluctuation of the load torque in the variable speed control will be considered. The difference in output between the variable speed control and the constant rotation control by the above simulation is shown in FIGS. 16 and 17. Each wind speed condition is V = 13 + 4sin 2πt / 10 (m / s) in FIG. 16 and V = 9 + 4sin 2πt / 10 (m / s) in FIG. Focusing on the output fluctuation level, in the case of FIG. 16,
In the variable speed control, it is reduced to about 1/2 of the constant rotation control, and to about 1/3 in Fig. 17 as well. Here, if the fluctuation of the rotational speed can be ignored as compared with the level of the output fluctuation, the output fluctuation level can be considered as the load torque fluctuation level received by the transmission system as it is. Therefore, the same input (wind speed)
It can be seen that the variable speed control is reduced to a fraction of the load condition in the variable speed control as compared with the constant speed control.
In the above simulation, the periodical fluctuation of the input (wind speed) is assumed, but the same load condition can be mitigated with respect to the influence of tower shadow, wind shear (wind condition distribution in the height direction), and the like.

Next, a comparison will be made between constant speed control of variable speed control of power required for pitch angle control. As described above, assuming that the gain in variable speed control is K _P = 9.0 and the gain in constant rotation control is K _P = 500, and the reaction torque (due to aerodynamic force, centrifugal force, etc.) during pitch control is the same. Since the required power is proportional to the pitch angle rotation speed, it can be considered as a ratio of K _P. Therefore, it is determined that the required power in the variable speed control may be about 1/50 of that in the constant rotation control. That is, power loss can be reduced by relaxing the pitch angle control accuracy and slowing the speed at which it is moved.

(Effects of the Invention) As described above, according to the control method of the present invention, the constant peripheral speed ratio is controlled by the program control having a predetermined relationship between the rotation speed of the generator or the rotor of the wind turbine and the output until the rated output range is reached. Alternatively, a variable speed operation close to that is performed, and the predetermined relationship between the rotational speed and the output is controlled by a constant peripheral speed ratio control for maintaining a large value of the wind turbine power coefficient, and a load control for maintaining the fluctuation of the rotational speed within a predetermined allowable range. The combination of the above algorithms makes it possible to perform wind power generation operation that enables easy acquisition of effective energy regardless of the type of generator under wind conditions that fluctuate irregularly, and reduces fluctuating load. In addition, the rotor rotation speed and output characteristics can be set appropriately in response to changes in the design conditions of structures such as wind turbine blades and towers, resulting in low cost, light weight, and high economic efficiency. The dynamic wind speed can be reduced, that is, the start-up characteristics can be improved, which contributes to the acquisition of effective energy. Furthermore, since the pitch angle control of the wind turbine blade can be slow, the control can be facilitated and the required power can be reduced. You can

[Brief description of drawings]

FIG. 1 is a basic configuration diagram of a wind turbine generator to which the control method of the present invention is applied, FIG. 2 is a characteristic diagram of power coefficient, output, and torque with respect to the rotational speed of a wind turbine, and FIG. FIG. 4 is a conceptual diagram of a control mode according to the method of the present invention, FIG. 5 is a relational diagram of program control according to the method of the present invention, and FIG. 6 is an explanatory diagram showing a driving locus according to the method of the present invention. FIG. 7 is an explanatory view of a control mode according to the method of the present invention, FIG. 8 is a relationship diagram between the rotational angular velocity of the wind turbine and the natural vibration angular velocity, FIG. 9 is a flow chart of the pitch conversion system control, and FIG. 10 is a generator control system. FIG. 11, FIG. 11 and FIG. 12 are configuration diagrams showing a concrete example of a wind turbine generator to which the present invention is applied, and FIGS. 13 to 17 are diagrams for explaining the operational effects of variable speed control and constant rotation control, respectively. Simulation results for FIG. 1 ... Windmill, 2 ... Power-power converter, 3 ... Control device, 4 ... Rotation speed sensor, 5 ... Output command generator, 6 ...
... output detection circuit, 7 ... comparison means.

Claims (1)

(57) [Claims] 1. A method for controlling a wind turbine generator that performs a variable speed control operation in which the rotational speed of a wind turbine is changed according to wind speed fluctuations, and the rotational speed and output of a generator or the rotor of a wind turbine are set until a rated output range is reached. A constant peripheral speed ratio or a variable speed motion close to it is performed by program control to keep the relationship as stated above, and after reaching the rated output range, the fluctuation of the rotational speed is kept within a predetermined allowable range by the pitch angle control of the wind turbine blade. Variable speed operation is performed to keep the output constant, and the setting relationship between the rotation speed and the output by the above program control is that the constant peripheral speed ratio control maintains a large value of the power coefficient of the wind turbine until the rotation speed approaches the rated rotation speed. , By changing the relationship between the rotational speed and the output in the direction of decreasing the peripheral speed ratio of the wind turbine before the rotational speed reaches the rated rotational speed, a negative limit for keeping the fluctuation of the rotational speed within a predetermined allowable range. Control method of a wind power generation apparatus characterized by having the algorithm of the control.