Wind driven generator control system

Abstract

The utility model discloses a wind driven generator control system. The system comprises a wind driven generator, a rectifier module, a voltage conversion module, a control module, an information acquisition module and a load module, the wind driven generator is used for generating alternating current voltage; the rectification module is used for converting the alternating current voltage into first direct current voltage; the voltage conversion module is used for converting the first direct-current voltage into second direct-current voltage; the information acquisition module is used for acquiring first information of the wind driven generator and second information of the load module; and the control module is used for adjusting the alternating voltage generated by the wind driven generator by adopting a perturbation and observation method, so that the output power of the voltage conversion module reaches preset target power. According to the embodiment of the invention, the pressure and wind curtailment phenomena caused by frequent use of the unloading device are avoided, and the heating phenomenon of the wind driven generator caused by overlarge load for a long time due to long-time use of the unloading module is avoided.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of wind driven generators, in particular to a wind driven generator control system. BACKGROUND

[0002] The wind driven generator is a power device which converts wind energy into mechanical work, and the mechanical work drives the rotor to rotate, and finally outputs alternating current. At present, when the wind speed is large, if the output power of the wind driven generator system is greater than the required power of the load module, in order to match the output power of the wind driven generator system with the required power of the load module, the existing scheme is to use an unloading module, and a part of the output power of the wind driven generator system is consumed by the unloading device, which will cause the unloading module to be frequently started and stopped, and the instantaneous large current caused by the frequent starting and stopping of the unloading module will impact the system. Moreover, when the wind speed is large for a long time, the unloading module needs to be operated for a long time, and since the unloading module consumes power in the form of heat, not only the unloading module generates a large amount of heat, but also the wind driven generator generates heat due to the large load for a long time. CONTENT OF THE UTILITY MODEL

[0003] The present application provides a wind driven generator control system to solve the problems of the existing technology that the unloading module is frequently started and stopped, the system is impacted, and the unloading module is operated for a long time, and the wind driven generator generates heat.

[0004] To achieve the above-mentioned purpose, the present application provides a wind driven generator control system, which comprises a wind driven generator, a rectifier module, a voltage conversion module, a control module, an information acquisition module and a load module.

[0005] The wind driven generator is connected with the input end of the rectifier module through the output end, and is used to generate alternating voltage.

[0006] The rectifier module is connected with the input end of the voltage conversion module through the first output end, and is used to convert the alternating voltage into first direct current voltage.

[0007] The voltage conversion module is connected with the input end of the load module through the output end of the direct current bus, and is used to convert the first direct current voltage into second direct current voltage.

[0008] The information acquisition module is connected with the input end of the control module through the output end, and is used to acquire the first information of the wind driven generator and the second information of the load module.

[0009] The control module is connected with the input end of the wind driven generator through the first control end, and is used to adjust the alternating voltage by using the perturbation and observation method, so that the output power of the voltage conversion module reaches the preset target power.

[0010] As an improvement of the above-mentioned scheme, the information collection module comprises:

[0011] a wind speed sensor, an output end of which is connected with an output end of the information collection module, for collecting a wind speed of an environment where the wind power generator is located;

[0012] a first voltage sensor, an output end of which is connected with an output end of the information collection module, for collecting the alternating voltage;

[0013] a first current sensor, an output end of which is connected with an output end of the information collection module, for collecting an output current of the wind power generator;

[0014] a second voltage sensor, an output end of which is connected with an output end of the information collection module, for collecting a voltage of the load module;

[0015] a second current sensor, an output end of which is connected with an output end of the information collection module, for collecting a current of the load module.

[0016] As an improvement of the above-mentioned scheme, the control module comprises a lookup table unit, a calculation unit, a comparison unit and a tracking unit;

[0017] the lookup table unit, an input end of which is connected with an input end of the control module, and an output end of which is connected with a first input end of the comparison unit, for obtaining a corresponding maximum output power according to the wind speed through lookup table;

[0018] the calculation unit, an input end of which is connected with an input end of the control module, and an output end of which is connected with a second input end of the comparison unit, for calculating the power of the load module according to the voltage of the load module and the current of the load module;

[0019] the comparison unit, an output end of which is connected with an input end of the tracking unit, for comparing the maximum output power and the power of the load module, and outputting a first comparison signal;

[0020] the tracking unit, a control end of which is connected with a first control end of the control module, for adjusting the alternating voltage according to the first comparison signal by using a perturbation and observation method, so that the output power of the voltage conversion module reaches the power indicated by the first comparison signal.

[0021] As an improvement of the above-mentioned scheme, if the maximum output power is greater than the power of the load module, the power indicated by the first comparison signal is the power of the load module; if the maximum output power is less than or equal to the power of the load module, the power indicated by the first comparison signal is the maximum output power.

[0022] As an improvement of the above-mentioned scheme, the control module further comprises:

[0023] a PWM control unit, an input end of which is connected with the input end of the control module, and a control end of which is connected with the second control end of the control module, for controlling the output current of the voltage conversion module by duty cycle;

[0024] As an improvement of the above-mentioned scheme, the rectifier module comprises a rectifier circuit and a first filter circuit connected in sequence.

[0025] As an improvement of the above-mentioned scheme, the voltage conversion module comprises a Bost circuit and a second filter circuit connected in sequence.

[0026] As an improvement of the above-mentioned scheme, the wind power generator control system further comprises:

[0027] a load relief module, a control end of which is connected with the third control end of the control module, and an input end of which is connected with the second output end of the rectifier module, for controlling the input and removal of the load relief module according to the comparison result between the instantaneous output current when starting the wind power generator and the preset maximum current.

[0028] As an improvement of the above-mentioned scheme, the wind power generator control system further comprises:

[0029] a storage module, which is connected with the control module, for storing the preset corresponding relation table of wind speed and optimal wind power generator speed, and the preset corresponding relation table of optimal wind power generator speed and maximum output power, or the preset corresponding relation table of wind speed, optimal wind power generator speed and maximum output power, or the preset corresponding relation table of wind speed and maximum output power.

[0030] As an improvement of the above-mentioned scheme, the load module comprises:

[0031] a storage battery, an input end of which is connected with the input end of the load module;

[0032] a plurality of loads, an input end of each of which is connected with the input end of the load module.

[0033] Compared with the prior art, the wind power generator control system provided by the embodiment of the application adjusts the alternating voltage generated by the wind power generator (i.e., the output voltage of the wind power generator) by setting the control module and using the perturbation and observation method, so that the output power of the voltage conversion module (i.e., the output power of the wind power generator system) reaches the preset target power and matches the required power of the load module (i.e., the rear-end load), thereby avoiding the need to use the unloading module to consume the over-generated power in the traditional scheme, reducing the use frequency of the unloading module to the greatest extent, avoiding the occurrence of the stress on the system and the wind power generation abandonment phenomenon caused by frequent use of the unloading module, and avoiding the occurrence of the heating phenomenon of the wind power generator caused by the long-time overloading of the wind power generator. In addition, the reserved unloading module only serves as a protection device to reduce the impact of the large current load during the start and stop of the wind power generator. BRIEF DESCRIPTION OF DRAWINGS

[0034] Figure 1 is a structural block diagram of a wind power generator control system provided by the embodiment of the application;

[0035] Figure 2 is another structural block diagram of a wind power generator control system provided by the embodiment of the application;

[0036] Figure 3 is still another structural block diagram of a wind power generator control system provided by the embodiment of the application;

[0037] Figure 4 is still another structural block diagram of a wind power generator control system provided by the embodiment of the application;

[0038] Figure 5 is still another structural block diagram of a wind power generator control system provided by the embodiment of the application;

[0039] Figure 6 is still another structural block diagram of a wind power generator control system provided by the embodiment of the application;

[0040] Figure 7 is still another structural block diagram of a wind power generator control system provided by the embodiment of the application;

[0041] Figure 8 is still another structural block diagram of a wind power generator control system provided by the embodiment of the application;

[0042] Figure 9 is a corresponding relationship diagram of the output voltage and the output power of the wind power generator at each rotational speed provided by the embodiment of the application;

[0043] Figure 10 is a relationship diagram of the load power curve and the wind turbine system output power curve provided by the embodiment of the application;

[0044] Figure 11 is another relationship diagram of the load power curve and the fan system output power curve provided by the embodiment of the present application;

[0045] Figure 12 is still another relationship diagram of the load power curve and the fan system output power curve provided by the embodiment of the present application;

[0046] Figure 13 is a flow chart of the wind power generator control system provided by the embodiment of the present application. DETAILED DESCRIPTION

[0047] The technical solutions in the embodiments of the present application will be clearly and completely described in combination with the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, but not all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor fall within the protection scope of the present application.

[0048] Referring to Figure 1 , Figure 1 is a structural block diagram of a wind power generator control system provided by the embodiment of the present application, the wind power generator control system comprising: a wind power generator 11, a rectification module 12, a voltage conversion module 13, a control module 14, an information acquisition module 15 and a load module 16;

[0049] The wind power generator 11 is connected with the input end of the rectification module 12, and is used for generating an alternating voltage;

[0050] The rectification module 12 is connected with the input end of the voltage conversion module 13, and is used for converting the alternating voltage into a first direct current voltage;

[0051] The voltage conversion module 13 is connected with the input end of the load module 16 through a direct current bus, and is used for converting the first direct current voltage into a second direct current voltage;

[0052] The information acquisition module 15 is connected with the input end of the control module 14, and is used for acquiring first information of the wind power generator 11 and second information of the load module 16;

[0053] The control module 14 is connected with the input end of the wind power generator 11, and is used for adjusting the alternating voltage by using a perturbation and observation method, so that the output power of the voltage conversion module 13 reaches a preset target power.

[0054] It can be understood that the embodiment of the application can be directly set to be used in the scene where the wind speed is large (for example, the wind speed of the environment where the wind turbine 11 is located is greater than a preset wind speed threshold), and the control module 14 adjusts the AC voltage by using the perturbation and observation method, so that the output power of the voltage conversion module 13 reaches a preset target power, which is set as the required power of the load module 16 in advance, so that the output power of the voltage conversion module 13 matches the required power of the load module 16. The embodiment of the application can not be provided with an unloading module, avoiding the use of the unloading module to consume the excess power in the traditional scheme, which can minimize the use frequency of the unloading module, not only avoiding the pressure on the system and the occurrence of the wind power abandonment phenomenon caused by the frequent use of the unloading module, but also avoiding the occurrence of the heating phenomenon of the wind turbine caused by the long-time overloading of the wind turbine.

[0055] The required power of the load module 16 is obtained by multiplying the voltage of the load module 16 and the current of the load module 16, that is, the required power of the load module 16 is obtained by multiplying the voltage of the load module 16 and the current of the load module 16.

[0056] In an alternative embodiment, as Figure 2 The information acquisition module 15 comprises:

[0057] A wind speed sensor, an output end of which is connected to an output end of the information acquisition module 15, for acquiring the wind speed of the environment where the wind turbine 11 is located;

[0058] A first voltage sensor, an output end of which is connected to an output end of the information acquisition module 15, for acquiring the AC voltage;

[0059] A first current sensor, an output end of which is connected to an output end of the information acquisition module 15, for acquiring the output current of the wind turbine 11;

[0060] A second voltage sensor, an output end of which is connected to an output end of the information acquisition module 15, for acquiring the voltage of the load module 16;

[0061] A second current sensor, an output end of which is connected to an output end of the information acquisition module 15, for acquiring the current of the load module 16.

[0062] In the embodiment of the present application, the wind speed sensor, the first voltage sensor, the first current sensor, the second voltage sensor and the second current sensor are arranged to collect the wind speed of the environment where the wind turbine 11 is located, the AC voltage, the output current of the wind turbine 11, the voltage of the load module 16 and the current of the load module 16 in real time. The voltage of the load module 16 is the voltage of the DC bus, and the current of the load module 16 is the current of the DC bus.

[0063] Further, the information collection module 15 further comprises a rotation speed sensor, an output end of the rotation speed sensor being connected with an output end of the information collection module, for collecting the rotation speed of the wind turbine.

[0064] In the embodiment of the present application, the rotation speed sensor is arranged to collect the rotation speed of the wind turbine 11 in real time.

[0065] In an alternative embodiment, as Figure 3 , the control module 14 comprises a lookup table unit, a calculation unit, a comparison unit and a tracking unit.

[0066] The lookup table unit is connected with the input end of the control module 14 and connected with the first input end of the comparison unit, for obtaining the corresponding maximum output power by looking up the table according to the wind speed.

[0067] The calculation unit is connected with the input end of the control module 14 and connected with the second input end of the comparison unit, for calculating the power of the load module 16 according to the voltage of the load module 16 and the current of the load module 16.

[0068] The comparison unit is connected with the input end of the tracking unit, for comparing the maximum output power and the power of the load module 16 and outputting a first comparison signal.

[0069] The tracking unit is connected with the first control end of the control module 14, for adjusting the AC voltage by using the perturbation and observation method according to the first comparison signal, so that the output power of the voltage conversion module 13 reaches the power indicated by the first comparison signal.

[0070] It can be understood that the maximum output power obtained by the table lookup is the maximum output power of the voltage conversion module at the optimal wind turbine speed corresponding to the current wind speed. Wherein, the wind turbine can obtain the maximum wind energy utilization coefficient at the optimal wind turbine speed. The correspondence table of wind speed and optimal wind turbine speed can be set in advance, and the correspondence table of optimal wind turbine speed and maximum output power can be set in advance, so as to obtain the corresponding maximum output power at the current wind speed by table lookup; the wind speed, the optimal wind turbine speed and the maximum output power can be set in advance, so as to obtain the corresponding maximum output power at the current wind speed by table lookup; or the correspondence table of wind speed and maximum output power can be directly set in advance, so as to obtain the corresponding maximum output power at the current wind speed by table lookup.

[0071] In an optional embodiment, if the maximum output power is greater than the power of the load module 16, the power indicated by the first comparison signal is the power of the load module 16; if the maximum output power is less than or equal to the power of the load module 16, the power indicated by the first comparison signal is the maximum output power.

[0072] It can be understood that the preset target power can be set as the power indicated by the first comparison signal in the embodiment of the application. Specifically, if the maximum output power is greater than the power of the load module 16, the power indicated by the first comparison signal is the power of the load module 16, that is, the first comparison signal indicates that the power of the load module 16 is the preset target power, so that the control module 14 adjusts the alternating voltage by using the perturb and observe method, so that the output power of the voltage conversion module 13 reaches the power of the load module 16; if the maximum output power is less than or equal to the power of the load module 16, the power indicated by the first comparison signal is the maximum output power, that is, the first comparison signal indicates that the maximum output power is the preset target power, so that the control module 14 adjusts the alternating voltage by using the perturb and observe method, so that the output power of the voltage conversion module 13 reaches the maximum output power.

[0073] In an optional embodiment, as Figure 4 , the control module 14 further comprises:

[0074] a PWM control unit, an input end of which is connected with the input end of the control module 14, a control end of which is connected with the second control end of the control module 14, and which is used for controlling the output current of the voltage conversion module 13 by duty cycle; and the second control end of the control module 14 is connected with the control end of the voltage conversion module 13.

[0075] In the embodiment of the present application, the output current of the voltage conversion module 13 is actively regulated to reduce the AC voltage generated by the wind driven generator 11, and then the output power of the wind driven generator 11 is controlled by changing the torque of the wind driven generator 11, and then the output power of the voltage conversion module 13 is controlled to be accurately matched with the required power of the load module 16.

[0076] In an alternative embodiment, as shown in Figure 5 , the rectifier module 12 comprises a rectifier circuit and a first filter circuit connected in sequence.

[0077] In the embodiment of the present application, the AC output of the wind driven generator 11 is converted to DC output by the rectifier module 12, and specifically, the rectifier circuit is a rectifier bridge and the first filter circuit is a first capacitor.

[0078] In an alternative embodiment, as shown in Figure 6 , the voltage conversion module 13 comprises a Bost circuit and a second filter circuit connected in sequence.

[0079] In the embodiment of the present application, the first DC voltage output by the rectifier module 12 is converted to a second DC voltage by the voltage conversion module 13 and output to the DC bus, and specifically, the second filter circuit is an inductor and a second capacitor.

[0080] In an alternative embodiment, as shown in Figure 7 , the wind driven generator control system further comprises:

[0081] The unloading module 17 has a control end connected to the third control end of the control module 14 and an input end connected to the second output end of the rectifier module 12, and is configured to control the input and removal of the unloading module 17 according to a comparison result between the instantaneous output current when the wind driven generator 11 is started and the preset maximum current.

[0082] In the embodiment of the present application, the unloading module can also be retained, and the retained unloading module 17 only serves as a protection device to reduce the impact of the large current load when the wind driven generator 11 is started and stopped.

[0083] In an alternative embodiment, as shown in Figure 8 , the wind driven generator control system further comprises:

[0084] The storage module 18 is connected to the control module 14 and is configured to store a preset correspondence table of wind speed and optimal wind driven generator speed, a preset correspondence table of optimal wind driven generator speed and maximum output power, or a preset correspondence table of wind speed, optimal wind driven generator speed and maximum output power, or a preset correspondence table of wind speed and maximum output power.

[0085] In the embodiment of the present application, the control module 14 can call the storage module to obtain the required information.

[0086] In an alternative embodiment, the load module 16 comprises:

[0087] a battery, the input end of which is connected to the input end of the load module 16;

[0088] a plurality of loads, the input end of each of which is connected to the input end of the load module 16.

[0089] For better understanding of the embodiments of the present application, the following will be described in detail:

[0090] The specific principle of the embodiments of the present application:

[0091] ① When the wind speed reaches 2 m / s, the wind turbine control system starts;

[0092] ② When the wind speed is low and the output power of the voltage conversion module is less than the required power of the load module, the speed of the wind turbine is controlled according to the real-time wind speed to maintain the optimal tip speed ratio to obtain the maximum wind energy utilization coefficient, to ensure the maximum output under the current wind speed, and the remaining load required energy is supplemented by photovoltaic, battery, mains and other energy sources;

[0093] ③ When the wind speed is large and the output power of the voltage conversion module is greater than the required power of the load module, the output current of the voltage conversion module is actively controlled according to the required power of the load module to reduce the alternating voltage generated by the wind turbine, thereby changing the torque of the wind turbine to control the output power of the wind turbine, and then controlling the output power of the voltage conversion module to quickly and accurately match the required power of the load. By changing the alternating voltage generated by the wind turbine, the number of triggering unloading voltage points is reduced to achieve the condition of unloading as little as possible, and the excess energy is balanced by the passive pitch structure of the front wind wheel. When the required power of the load module decreases and the wind speed remains unchanged, the wind wheel energy is greater than the required power, the speed of the wind turbine is changed by controlling the torque, and then the output power of the wind turbine is controlled, thereby controlling the output power of the voltage conversion module. The wind turbine used in the embodiments of the present application is a mechanical centrifugal passive pitch wind turbine. After actively increasing the speed of the wind turbine to meet the centrifugal pitch condition, the passive centrifugal pitch structure is actively triggered to change the blade angle, so that the wind wheel absorbs less energy and automatically balances the power of the front and rear ends.

[0094] According to the output formula of the wind turbine P=T×2π×n / 60, where P is the output power of the wind turbine, unit KW; T is the torque of the wind turbine, unit N·m; n is the speed of the wind turbine, unit r / min. It can be seen that the output power of the wind turbine is related to the speed and torque.

[0095] The rotation speed of the wind turbine and the wind energy utilization coefficient C p Correlation, C p The expression is:

[0096]

[0097] Wherein, β is the blade pitch angle, The tip speed ratio, Wherein, R is the wind wheel radius, n is the rotation speed of the wind turbine, and v is the wind speed. When the blade pitch angle β is constant, there is only one maximum value C pmax Corresponding to a unique tip speed ratio Therefore, under different wind speeds v, there is a certain rotation speed n of the wind turbine corresponding to the optimal tip speed ratio And get the maximum wind energy utilization coefficient C pmax The optimal wind turbine speed n under a certain wind speed is calculated and stored. In this system, through the wind speed feedback of the anemometer in the wind turbine, the rear-end controller looks up the table and adjusts the rotation speed of the wind turbine to the optimal wind turbine speed under the wind speed, so as to obtain the optimal wind energy utilization coefficient. When the blade pitch angle β increases, the wind energy utilization coefficient C p With the increase of the blade pitch angle β, the wind energy utilization coefficient C

[0098] The change of the torque of the wind turbine will also affect the output power of the wind turbine. By limiting the output current of the voltage conversion module, the alternating voltage generated by the wind turbine can be changed, and then the torque of the wind turbine can be changed. The output characteristic table of the 5kW / 200V motor used by the mechanical centrifugal pitch wind turbine is shown in Table 1, and the corresponding relationship between the output voltage and the output power of the wind turbine at each rotation speed is shown in Figure 9

[0099] Table 1 5kW / 200V wind turbine output characteristic table

[0100]

[0101] From Figure 9 It can be seen that the voltage-output power of the wind turbine at different rotation speeds presents a parabolic shape, and with the increase of the voltage, the output power of the wind turbine first increases to the maximum power point, and then gradually decreases. Similarly, the output power of the voltage conversion module presents the same trend, first increases to the maximum power point, and then gradually decreases.

[0102] ​The system adopts the disturbance observation method to track the maximum power point, i.e. the preset target power. The AC voltage generated by the wind driven generator is changed to observe the corresponding power change, and then the preset target power is approached. Two voltage change steps are set. When the preset target power is compared with the current output power, the AC voltage generated by the wind driven generator is changed with a large step to quickly approach the preset target power when the difference is large, and the AC voltage generated by the wind driven generator is changed with a small step to accurately match the preset target power when the difference is small. In the system, after the speed of the wind driven generator is adjusted to the optimal wind driven generator speed, the voltage and current of the load module are monitored, the required power is calculated, and the maximum output power at the wind speed is compared, the preset target power is adjusted, and the following two cases exist:

[0103] (1) The required power of the load is greater than or equal to the maximum output power

[0104] As shown in Figure 10 , when the required power of the load is greater than or equal to the maximum output power, the load power curve is above the fan system output power curve or is tangent to the fan system output power curve. In this case, the wind driven generator should maintain the output power, so that the output power of the voltage conversion module is the maximum output power at the wind speed, and therefore the tracked preset target power should be the maximum point of the fan system output power curve.

[0105] (2) The required power of the load is within the output power range

[0106] When the required power of the load is within the output power range, the load power curve intersects with the fan system output power curve, and there can be 1-2 intersection points, as shown in Figures 11-12 . In this case, the wind driven generator should limit the output power so that the output power of the voltage conversion module is equal to the required power of the load module, and therefore the tracked preset target power should be the intersection point of the load power curve and the fan system output power curve. In the case of two intersection points, the right intersection point has the same curve relationship as the case of one intersection point, that is, when the output voltage is increased, the output power will gradually decrease to approach the preset target power. Therefore, when the output power of the voltage conversion module is greater than the required power of the load module, the system will increase the AC voltage generated by the wind driven generator to track the right intersection point as the preset target power.

[0107] The overall flow of the embodiment of the application is as shown in Figure 13Where P (target) is the power to be tracked, i.e. the preset target power, P (max) is the maximum output power at the wind speed, P (load) is the power required by the load module; P (K) is the output power of the voltage conversion module at the current moment, U (K) is the output voltage of the wind generator at the current moment; P (K-1) is the output power of the voltage conversion module before the last cycle, U (K-1) is the output voltage of the wind generator before the last cycle; ΔU1 is a small step, ΔU1 = 2V; ΔU2 is a large step, ΔU2 = 6V.

[0108] Collecting the current wind speed V 风速 , and obtaining the corresponding maximum output power at the current wind speed through table lookup;

[0109] The voltage of the load module is measured by the second voltage sensor, and the current of the load module is measured by the second current sensor, the power required by the load is calculated and judged, if the maximum output power is greater than the power required by the load module, the preset target power to be tracked is the power required by the load module; otherwise, the preset target power to be tracked is the maximum output power.

[0110] The current output power P (K) is compared with the preset target power P (target), if greater than or equal to, the left branch is taken to continue comparison. If the two are equal, the leftmost branch is taken, the current output value is maintained and the cycle is ended. If the current output power P (K) is greater than the preset target power P (target), there should be two cases, one working in the d region of Figure 12 , and one working in the a region of Figure 11 . At this time, the output voltage is increased by a step value, i.e. the current point on the fan system output power curve is moved right by a step, for the case of 2 intersection points, the right intersection point is tracked right; for the case of 1 intersection point, the unique intersection point is also tracked right. Then comparison is made, if the absolute value of the difference between the current output power P (K) and the preset target power P (target) is less than 0.5W, the preset target power is slowly approached with a small step; if greater than 0.5W, the preset target power is quickly approached with a large step. Finally, return to the beginning and continue the cycle.

[0111] If the current output power P (K) < the preset target power P (target), and:

[0112] 1) The current output power P (K) < the output power P (K-1) before the last cycle, and the current output voltage U (K) < the output voltage U (K-1) before the last cycle, i.e. the power is reduced after moving left by a step on the fan system output power curve, working in the d region of Figure 12If the output voltage is in region c, it should move right to track the preset target power, increasing the output voltage by one step. A comparison is then performed. If the absolute value of the difference between the current output power P(K) and the preset target power P(target) is less than 0.5W, the target point is slowly approached with small steps. If it is greater than 0.5W, the target power is quickly approached with large steps. Finally, the circuit returns to the beginning and the cycle continues.

[0113] 2) The current output power P(K) < the output power P(K-1) before the last cycle, and the current output voltage U(K) > the output voltage U(K-1) before the last cycle, that is, the power decreases after moving one step to the right on the output power curve of the fan system, and the fan system works at Figure 11 b area or Figure 12 If the output voltage is in the e region, it should move left to the preset target power, that is, reduce the output voltage by one step size. Then, if the absolute value of the difference between the current power P(K) and the preset target power P(target) is less than 0.5W, the preset target power is slowly approached with small steps. If it is greater than 0.5W, the preset target power is quickly approached with large steps. Finally, return to the beginning and continue the cycle.

[0114] 3) If the current output power P(K) is greater than the output power P(K-1) before the previous cycle, and the current output voltage U(K) is less than the output voltage U(K-1) before the previous cycle, then the system's power increases after a step shift to the left on the wind turbine system's output power curve. The operating area is the same as in case 2). The system should shift left to track the preset target power. This means reducing the output voltage by one step. The absolute value of the difference between the current power P(K) and the preset target power P(target) is then compared to determine the appropriate step size. Finally, the system returns to the beginning and continues the cycle.

[0115] 4) If the current output power P(K) is greater than the output power P(K-1) before the previous cycle, and the current output voltage U(K) is greater than the output voltage U(K-1) before the previous cycle, then the system's power increases after a rightward shift of one step on the wind turbine system's output power curve. The operating area is the same as in case 1), and the system should shift rightward to track the preset target power, increasing the output voltage by one step. The absolute value of the difference between the current output power P(K) and the preset target power P(target) is then compared to determine the appropriate step size for the reduction. Finally, the system returns to the beginning and the cycle continues.

[0116] The above is a preferred embodiment of the present application. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principles of the present application. These improvements and modifications are also considered to be within the scope of protection of the present application.

Claims

1. A wind power generator control system, characterized in that, The wind power generator, the rectifier module, the voltage conversion module, the control module, the information acquisition module and the load module are connected in series. The wind power generator is connected with the input end of the rectifier module, and is used for generating alternating voltage. The first output end of the rectifier module is connected with the input end of the voltage conversion module, and is used for converting the alternating voltage into first direct current voltage. The output end of the voltage conversion module is connected with the input end of the load module through a direct current bus, and is used for converting the first direct current voltage into second direct current voltage. The output end of the information acquisition module is connected with the input end of the control module, and is used for acquiring first information of the wind power generator and second information of the load module. The first control end of the control module is connected with the input end of the wind power generator, and is used for adjusting the alternating voltage by using the perturb and observe method, so that the output power of the voltage conversion module reaches preset target power.

2. A wind power generator control system according to claim 1, characterised in that, The information acquisition module comprises: A wind speed sensor, whose output end is connected with the output end of the information acquisition module, is used for acquiring wind speed of the environment where the wind power generator is located. A first voltage sensor, whose output end is connected with the output end of the information acquisition module, is used for acquiring the alternating voltage. A first current sensor, whose output end is connected with the output end of the information acquisition module, is used for acquiring output current of the wind power generator. A second voltage sensor, whose output end is connected with the output end of the information acquisition module, is used for acquiring voltage of the load module. A second current sensor, whose output end is connected with the output end of the information acquisition module, is used for acquiring current of the load module.

3. A wind generator control system as claimed in claim 2, wherein, The control module comprises a lookup table unit, a calculation unit, a comparison unit and a tracking unit. The lookup table unit is connected with the input end of the control module, and is connected with the first input end of the comparison unit, and is used for obtaining corresponding maximum output power by looking up a table according to the wind speed. The calculation unit is connected with the input end of the control module, and is connected with the second input end of the comparison unit, and is used for calculating power of the load module according to voltage of the load module and current of the load module. The comparison unit is connected with the input end of the tracking unit, and is used for comparing the maximum output power and the power of the load module, and outputting a first comparison signal. The tracking unit is connected with the first control end of the control module, and is used for adjusting the alternating voltage by using the perturb and observe method according to the first comparison signal, so that the output power of the voltage conversion module reaches power indicated by the first comparison signal.

4. A wind generator control system as claimed in claim 3, wherein, If the maximum output power is greater than the power of the load module, the power indicated by the first comparison signal is the power of the load module; if the maximum output power is less than or equal to the power of the load module, the power indicated by the first comparison signal is the maximum output power.

5. A wind power generator control system according to claim 3, wherein The control module further comprises: A PWM control unit, an input end of which is connected with the input end of the control module, and a control end of which is connected with the second control end of the control module, is used for controlling the output current of the voltage conversion module by duty cycle.

6. The wind power generator control system according to claim 1, wherein The rectification module comprises a rectification circuit and a first filter circuit connected in sequence.

7. The wind power generator control system according to claim 1, wherein The voltage conversion module comprises a Bost circuit and a second filter circuit connected in sequence.

8. The wind power generator control system of claim 1, wherein, The wind driven generator control system further comprises: An unloading module, a control end of which is connected with the third control end of the control module, and an input end of which is connected with the second output end of the rectification module, is used for controlling the input and cut-off of the unloading module according to the comparison result between the instantaneous output current and the preset maximum current when starting the wind driven generator.

9. The wind power generator control system according to claim 1, wherein The wind driven generator control system further comprises: A storage module, which is connected with the control module, is used for storing the preset corresponding relation table of wind speed and optimal wind driven generator rotating speed, and the preset corresponding relation table of optimal wind driven generator rotating speed and maximum output power; or, the preset corresponding relation table of wind speed, optimal wind driven generator rotating speed and maximum output power; or, the preset corresponding relation table of wind speed and maximum output power.

10. The wind power generator control system as claimed in claim 1, wherein The load module comprises: A storage battery, an input end of which is connected with the input end of the load module; A plurality of loads, an input end of each of which is connected with the input end of the load module.

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