Wind driven generator blade deicing system based on pulse deicing

Abstract

The invention provides a wind driven generator blade deicing system based on pulse deicing. The wind driven generator blade deicing system comprises a detection module, a deicing module and a deicing control module. The deicing module comprises a magnet exciting coil and a skin, the magnet exciting coil is attached to a set deicing point of the fan blade, the skin is fixed to the surface of the fan blade at the deicing point, and the magnet exciting coil is completely covered with the skin; the deicing control module comprises a control unit and an excitation driving unit; the control unit is used for receiving the icing detection signal output by the detection module, judging the icing thickness and controlling the excitation driving unit to work according to the icing thickness so as to output excitation pulses to the corresponding excitation coils.

Description

Technical Field

[0001] The invention relates to an electric deicing system, in particular to a wind turbine blade deicing system based on pulse deicing. Background Art

[0002] When wind turbines are installed in high altitude areas, they inevitably face the problem of blade icing. When blades are covered with ice, their aerodynamic performance is affected, which in turn reduces the power generation and efficiency of the wind turbine. When the ice is severe, it may even cause the wind turbine to malfunction or stop operating.

[0003] There are generally two ways to de-ice fan blades. One is electric heating de-icing, and the other is vibration de-icing. The electric heating de-icing method has the problem of high energy consumption and poor economy. The vibration de-icing in the prior art is difficult to effectively remove the ice on the blades, that is, vibration de-icing often leaves ice residue, which still affects the operation of the fan.

[0004] Therefore, in order to solve the above technical problems, it is urgent to propose a new technical means. Summary of the invention

[0005] In view of this, the purpose of the present invention is to provide a wind turbine blade de-icing system based on pulse de-icing, which generates eddy currents on the skin by means of electric pulses, and then generates mechanical vibrations, and removes ice from the wind turbine blades through the mechanical vibrations. It can effectively and more thoroughly remove the ice on the blades without affecting the power generation performance of the wind turbine, reduce the mechanical load on the wind turbine blades, and ensure the efficiency and stability of wind turbine power generation in winter.

[0006] The present invention provides a wind turbine blade deicing system based on pulse deicing, comprising a detection module, a deicing module and a deicing control module;

[0007] The deicing module includes an excitation coil and a skin, wherein the excitation coil is attached to the deicing point set for the fan blade, and the skin is fixed to the surface of the fan blade at the deicing point and the excitation coil is completely covered by the skin;

[0008] The de-icing control module includes a control unit and an excitation drive unit;

[0009] The control unit is used to receive the ice coating detection signal output by the detection module and determine the ice coating thickness, and control the excitation drive unit to work according to the ice coating thickness, so as to output an excitation pulse to the corresponding excitation coil.

[0010] Furthermore, the control unit controls the action of the excitation drive unit according to the ice thickness, specifically including:

[0011] The control unit calculates the ice thickness at each deicing point based on the detection signal;

[0012] Sort the ice thickness of each deicing point from small to large;

[0013] The control unit uses the ice thickness sequence as the de-icing action priority sequence to control the corresponding excitation drive units to work in sequence.

[0014] Furthermore, the excitation unit includes a voltage doubling circuit, an energy storage charging circuit and an excitation coil control circuit;

[0015] The input end of the voltage doubling circuit is connected to the power supply, the output end of the voltage doubling circuit is connected to the input end of the energy storage charging circuit, the output end of the energy storage charging circuit is connected to the excitation coil control circuit, and the excitation coil control circuit supplies power to the excitation coil; the control input ends of the energy storage charging circuit and the excitation coil control circuit are connected to the control unit.

[0016] Further, the energy storage charging circuit includes an electronic switch Q1, a resistor R1 and a capacitor CR;

[0017] The input end of the electronic switch Q1 is connected to the output end of the voltage doubling circuit, the output end of the electronic switch Q1 is connected in series with the resistor R1 and the capacitor CR and then grounded, the common connection point between the resistor R1 and the capacitor CR serves as the output end of the energy storage charging circuit, and the control end of the electronic switch Q1 is connected to the control unit.

[0018] Further, the excitation coil control circuit includes an electronic switch Q2 and a resistor R2;

[0019] The input end of the electronic switch Q2 is connected to the output end of the energy storage charging circuit, the output end of the electronic switch Q2 is connected to one end of the resistor R2 through the excitation coil L1, the other end of the resistor R2 is grounded, and the control end of the electronic switch Q2 is connected to the control unit.

[0020] Furthermore, the excitation current is input to the excitation coil of each deicing point at least twice, and after all deicing actions of the deicing points with a high priority are completed, the deicing action is performed on the deicing point with the next priority.

[0021] Furthermore, the input voltage of the next deicing action of the excitation coil of each deicing point is lower than the previous deicing action voltage, and the deicing action voltage of the excitation coil is determined by the following formula:

[0022] Where t is the charging time of capacitor CR, V max is the maximum voltage output by the voltage doubler circuit, and RC is the time coefficient.

[0023] The beneficial effects of the present invention are as follows: Through the present invention, eddy currents are generated on the skin by means of electric pulses, thereby generating mechanical vibrations, and the ice on the wind turbine blades is removed by the mechanical vibrations. The ice on the blades can be removed effectively and more thoroughly without affecting the power generation performance of the wind turbine, thereby reducing the mechanical load on the wind turbine blades and ensuring the efficiency and stability of wind turbine power generation in winter. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] The present invention will be further described below in conjunction with the accompanying drawings and embodiments:

[0025] Figure 1 It is a schematic diagram of the deicing point arrangement structure in the present invention.

[0026] Figure 2 It is a schematic diagram of the voltage doubling circuit structure of the present invention.

[0027] Figure 3 It is a schematic diagram of the structure of the energy storage charging circuit of the present invention.

[0028] Figure 4 It is a schematic diagram of the structure of the excitation coil control circuit of the present invention.

[0029] Figure 5 It is a schematic diagram of the electrical structure of the present invention. DETAILED DESCRIPTION

[0030] The present invention is further described in detail below:

[0031] The present invention provides a wind turbine blade deicing system based on pulse deicing, comprising a detection module, a deicing module and a deicing control module;

[0032] The deicing module includes an excitation coil and a skin, wherein the excitation coil is attached to the deicing point set for the fan blade, and the skin is fixed to the surface of the fan blade at the deicing point and the excitation coil is completely covered by the skin; Figure 1 As shown, Figure 1 The middle circle indicates the deicing point. The distance between two adjacent deicing points is set to 1 meter, and the distance between the deicing point and the windward edge of the blade is set to 0.5 meter. This arrangement is more conducive to deicing.

[0033] The de-icing control module includes a control unit and an excitation drive unit;

[0034] The control unit is used to receive the ice detection signal output by the detection module and determine the ice thickness, and control the excitation drive unit to work according to the ice thickness, so as to output an excitation pulse to the corresponding excitation coil. Among them, the control unit adopts an existing single-chip microcomputer, the detection module adopts an existing camera, and the existing algorithm is used to estimate the ice thickness of each deicing point of the fan blade through the acquired blade image information. It will not be repeated here. Through the above structure, eddy currents are generated on the skin by means of electric pulses, and then mechanical vibrations are generated. The ice on the fan blades is removed by the mechanical vibration, and the ice on the blades can be effectively and more thoroughly removed without affecting the power generation performance of the wind turbine, reducing the mechanical load of the fan blades, and ensuring the efficiency and stability of wind turbine power generation in winter.

[0035] The skin can be made of aluminum material, which has a relatively small mass and can reduce the load on the blades. The skin is fixed to the surface of the wind turbine blades by rivets.

[0036] In this embodiment, the control unit controls the action of the excitation drive unit according to the ice thickness, specifically including:

[0037] The control unit calculates the ice thickness at each deicing point based on the detection signal;

[0038] Sort the ice thickness of each deicing point from small to large;

[0039] The control unit uses the ice thickness sequence as the de-icing action priority sequence to control the corresponding excitation drive units to work in sequence. The thicker the ice thickness, the stronger the adhesion between the ice and the blade surface. Therefore, de-icing is performed first at the location with a smaller ice thickness to destroy the ice layer and gradually reduce the adhesion between the ice and the blade in the thicker ice area, which is more conducive to removing the ice.

[0040] In this embodiment, the excitation unit includes a voltage doubling circuit, an energy storage charging circuit and an excitation coil control circuit;

[0041] The input end of the voltage doubling circuit is connected to the power supply, the output end of the voltage doubling circuit is connected to the input end of the energy storage charging circuit, the output end of the energy storage charging circuit is connected to the excitation coil control circuit, the excitation coil control circuit supplies power to the excitation coil; the control input ends of the energy storage charging circuit and the excitation coil control circuit are connected to the control unit. The control unit adopts an existing single chip microcomputer, which will not be described in detail here.

[0042] Specifically: the energy storage charging circuit includes an electronic switch Q1, a resistor R1 and a capacitor CR;

[0043] The input end of the electronic switch Q1 is connected to the output end of the voltage doubling circuit, the output end of the electronic switch Q1 is connected in series with the resistor R1 and the capacitor CR and then grounded, the common connection point between the resistor R1 and the capacitor CR serves as the output end of the energy storage charging circuit, and the control end of the electronic switch Q1 is connected to the control unit.

[0044] The excitation coil control circuit includes an electronic switch Q2 and a resistor R2;

[0045] The input end of the electronic switch Q2 is connected to the output end of the energy storage charging circuit, the output end of the electronic switch Q2 is connected to one end of the resistor R2 through the excitation coil L1, the other end of the resistor R2 is grounded, and the control end of the electronic switch Q2 is connected to the control unit. The electronic switch can be implemented by existing NMOS switches, triodes, etc. The on and off of Q2 and Q1 are: when charging Cr, Q1 is turned on and Q2 is turned off. After Cr is charged, Q1 is turned off and Q2 works, and the control signal of Q2 is a PWM signal, so as to perform pulse discharge. When Cr is discharged, the next time the capacitor Cr at the current deicing point is charged, a time interval is required, which is at least the time required for the excitation coil to dissipate heat.

[0046] In this embodiment, the excitation current is input into the excitation coil of each deicing point at least twice, and after all deicing actions of the deicing points with higher priority are completed, the deicing action is performed on the deicing point with the next priority. Generally speaking, one deicing point needs to perform four deicing actions, that is, the capacitor is charged and discharged four times, and then the deicing action is performed on the next deicing point. Through the above, the ice covering the fan blades can be removed more thoroughly.

[0047] In this embodiment, the input voltage of the excitation coil of each deicing point in the next deicing action is lower than the voltage of the previous deicing action, and the deicing action voltage of the excitation coil is determined by the following formula:

[0048] Where t is the charging time of capacitor CR, V max is the maximum voltage output by the voltage doubler circuit, and RC is the time coefficient. In this way, it can ensure that the mechanical vibration generated by the excitation pulse has sufficient destructive power and can also save energy to a certain extent.

[0049] Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solution of the present invention can be modified or replaced by equivalents without departing from the purpose and scope of the technical solution of the present invention, which should be included in the scope of the claims of the present invention.

Claims

1. A wind turbine blade deicing system based on pulse deicing, characterized in that: It includes a detection module, a deicing module and a deicing control module; The deicing module includes an excitation coil and a skin, wherein the excitation coil is attached to the deicing point set for the fan blade, and the skin is fixed to the surface of the fan blade at the deicing point and the excitation coil is completely covered by the skin; The de-icing control module includes a control unit and an excitation drive unit; The control unit is used to receive the ice coating detection signal output by the detection module and determine the ice coating thickness, and control the excitation drive unit to work according to the ice coating thickness, so as to output an excitation pulse to the corresponding excitation coil.

2. The wind turbine blade deicing system based on pulse deicing according to claim 1 is characterized in that: The control unit controls the action of the excitation drive unit according to the ice thickness, specifically including: The control unit calculates the ice thickness at each deicing point based on the detection signal; Sort the ice thickness of each deicing point from small to large; The control unit uses the ice thickness sequence as the de-icing action priority sequence to control the corresponding excitation drive units to work in sequence.

3. The wind turbine blade deicing system based on pulse deicing according to claim 2 is characterized in that: The excitation unit includes a voltage doubling circuit, an energy storage charging circuit and an excitation coil control circuit; The input end of the voltage doubling circuit is connected to the power supply, the output end of the voltage doubling circuit is connected to the input end of the energy storage charging circuit, the output end of the energy storage charging circuit is connected to the excitation coil control circuit, and the excitation coil control circuit supplies power to the excitation coil; the control input ends of the energy storage charging circuit and the excitation coil control circuit are connected to the control unit.

4. The wind turbine blade deicing system based on pulse deicing according to claim 3 is characterized in that: The energy storage charging circuit includes an electronic switch Q1, a resistor R1 and a capacitor CR; The input end of the electronic switch Q1 is connected to the output end of the voltage doubling circuit, the output end of the electronic switch Q1 is connected in series with the resistor R1 and the capacitor CR and then grounded, the common connection point between the resistor R1 and the capacitor CR serves as the output end of the energy storage charging circuit, and the control end of the electronic switch Q1 is connected to the control unit.

5. The wind turbine blade deicing system based on pulse deicing according to claim 4 is characterized in that: The excitation coil control circuit includes an electronic switch Q2 and a resistor R2; The input end of the electronic switch Q2 is connected to the output end of the energy storage charging circuit, the output end of the electronic switch Q2 is connected to one end of the resistor R2 through the excitation coil L1, the other end of the resistor R2 is grounded, and the control end of the electronic switch Q2 is connected to the control unit.

6. The wind turbine blade deicing system based on pulse deicing according to claim 4 is characterized in that: The excitation current is input to the excitation coil of each deicing point at least twice, and after all deicing actions of the deicing points with a high priority are completed, the deicing action is performed on the deicing point with the next priority.

7. The wind turbine blade deicing system based on pulse deicing according to claim 6 is characterized in that: The input voltage of the next deicing action of the excitation coil of each deicing point is lower than the previous deicing action voltage, and the deicing action voltage of the excitation coil is determined by the following formula: Where t is the charging time of capacitor CR, V max is the maximum voltage output by the voltage doubler circuit, and RC is the time coefficient.

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