Insulation material for power cable of low-voltage wind turbine generator and preparation method

Abstract

An insulation material for a power cable of a low-voltage wind turbine generator, and a preparation method, belonging to the technical field of wind power generation. By combining the properties of multiple raw materials and leveraging the respective strengths thereof, the present invention exhibits properties such as excellent aging resistance, high and low temperature resistance and high strength. A composite of three anti-aging agents, anti-aging agent RD, anti-aging agent MB and anti-aging agent XH-3, is used to comprehensively improve the heat resistance of the insulation. Compared with a single anti-aging agent, the anti-aging agents can have a synergistic effect, resulting in superior heat resistance, and the tensile strength and elongation at break thereof can remain at a high level after thermal aging. By means of optimization of the formula, the cable meets environmental protection requirements.

Description

Insulation material and preparation method for low-voltage wind turbine power cable Technical Field

[0001] The present application relates to the field of wind power generation technology, for example, an insulation material for a power cable of a wind turbine generator set and a preparation method thereof. Background Art

[0002] The development of wind energy can effectively alleviate the current energy shortage. Compared to other new energy sources, wind energy is a renewable and inexhaustible source of energy. Furthermore, wind power generation is a major global priority due to its vast reserves. Even 1% of wind energy can meet human energy needs, reducing carbon dioxide emissions, minimizing the greenhouse effect, and achieving sustainable development.

[0003] As calls for wind and thermal power generation to achieve parity in power costs grow, the trend toward cost reduction in wind power generation is becoming increasingly evident. Renovating older power lines to increase transmission capacity is imperative. Without changing the existing line voltage, increasing the allowable current carrying capacity of cables is the primary approach to improving normal transmission capacity. To meet the high load demands of cables, it is essential to increase their current carrying capacity, long-term operating temperature tolerance, and maximum operating temperature. This ensures reliable and safe operation and prevents thermal and electrical aging insulation failures. This allows for dynamic capacity expansion based on the cable's real-time operating environment.

[0004] The power cables of wind turbines are generally insulated with 90℃ ethylene propylene rubber. If the method of increasing the cross-section is used to improve the current transmission capacity, not only the cables need to be replaced, but also the supporting components such as cable clamps need to be redesigned, which will increase the cost significantly. If the current carrying capacity is improved by increasing the operating temperature of the cable, it will cause cable overload, accelerate the aging of the insulation layer, and easily cause fire.

[0005] Currently, the long-term operating temperature of conventional wind power cables is 90°C. Because the insulation layer can only withstand temperatures up to 90°C, this limits the cable's current carrying capacity. Therefore, it is necessary to develop materials that can improve the insulation's heat resistance and aging resistance while also meeting environmental requirements.

[0006] Summary of the Invention

[0007] The following is a summary of the subject matter described in detail herein. This summary is not intended to limit the scope of the claims.

[0008] To solve the above technical problems, the present application provides an insulation material and preparation method for a low-voltage wind turbine power cable, namely, an insulation material and preparation method for a wind turbine power cable with a rated voltage of 1.8 / 3kV.

[0009] This application is implemented through the following technical solutions:

[0010] The first object of the present application is to provide an insulation material for a low-voltage wind turbine power cable, comprising the following components by weight:

[0011] In one embodiment of the present application, the antioxidants are antioxidant RD, antioxidant MB, and antioxidant XH-3; the mass ratio of antioxidant RD to antioxidant MB is 1:1. Antioxidant RD can be purchased from Sinopec Nanjing Chemical Industry Co., Ltd., also known as rubber antioxidant TMQ; antioxidant MB can be purchased from Jiangsu Huaxing New Materials Technology Co., Ltd.; and antioxidant XH-3 can be purchased from Taizhou Xubang New Materials Development Co., Ltd.

[0012] In one embodiment of the present application, the antioxidant RD is 1.0-2.0 parts; the antioxidant MB is 1.0-2.0 parts.

[0013] In one embodiment of the present application, the talc powder is selected from talc powder 1250 mesh.

[0014] In one embodiment of the present application, the vulcanizing agent is selected from DCP.

[0015] In one embodiment of the present application, the coupling agent is selected from coupling agent A-172. The coupling agent A-172 can be purchased from Linjing Chemical (Shanghai) Co., Ltd.

[0016] In one embodiment of the present application, the vulcanization auxiliary agent is selected from triallyl isocyanurate.

[0017] The second object of the present application is to provide a method for preparing an insulation material for a low-voltage wind turbine power cable, comprising the following steps:

[0018] 1) mixing the EPDM rubber in an internal mixer;

[0019] 2) adding talc, modified calcined kaolin, nano zinc oxide, microcrystalline wax, titanium dioxide, stearic acid, antioxidant, paraffin oil and coupling agent to the mixture obtained in step 1), and mixing in an internal mixer for 2-3 minutes;

[0020] 3) adding a vulcanizing agent and a vulcanizing aid to the mixture obtained in step 2), and mixing in an internal mixer for 0.5 min to 1.5 min to obtain a mixed rubber material;

[0021] 4) The mixed rubber material obtained in step 3) is thinned on an open mill 1-2 times, while the rubber is swung 2-3 times, and then cut into sheets. After passing through a talcum powder box, the insulation material for the low-voltage wind turbine power cable is obtained.

[0022] In one embodiment of the present application, in step 1), the mixing conditions are: mixing at 90° C.-110° C. for 2 min-3 min.

[0023] The third object of the present application is to provide a low-voltage wind turbine generator power cable, comprising a conductor, an insulating layer and an outer sheath; the insulating layer is made of the insulating material.

[0024] The above technical solution of the present application has the following advantages over the prior art:

[0025] (1) This application provides an insulation material and preparation method for a low-voltage wind turbine power cable (the structural diagram of the wind turbine power cable is shown in Figure 1). This application integrates the performance of multiple raw materials, taking advantage of their strengths and overcoming their weaknesses, and has excellent aging resistance, high and low temperature resistance, high strength and other properties. Experiments have shown that the insulation performance of this application is qualified at an operating temperature of 125°C, the preparation process is simple, and the operability is strong.

[0026] (2) This application increases the current carrying capacity by more than 20% while ensuring that the cable structure size and weight remain unchanged.

[0027] (3) The three antioxidants described in this application, antioxidant RD, antioxidant MB, and antioxidant XH-3, are compounded to improve the heat resistance of the insulation as a whole. Compared with a single antioxidant, the antioxidants produce a synergistic effect, resulting in better heat resistance. Its tensile strength and elongation at break can still maintain a high level after thermal aging, and can solve the problem of frost on the rubber surface. And through the optimization of the formula, the cable meets environmental protection requirements (each formula small material is made of environmentally friendly materials).

[0028] Still other aspects will become apparent upon reading and understanding the accompanying drawings and detailed description. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] The accompanying drawings are used to provide a further understanding of the technical solution of this article and constitute a part of the specification. Together with the embodiments of this application, they are used to explain the technical solution of this article and do not constitute a limitation on the technical solution of this article.

[0030] In order to make the content of this application easier to understand, the following is a further detailed description of this application based on the specific embodiments of this application and in conjunction with the accompanying drawings, wherein

[0031] FIG1 is a schematic structural diagram of a power cable for a wind turbine generator set according to the present invention; wherein 1 is a conductor; 2 is an insulation layer; 3 is an outer sheath;

[0032] FIG2 shows the sample state before and after aging of the sample prepared in Example 1 (adding 1.5 parts of RD and 1.5 parts of MB) in the performance test of this application;

[0033] FIG3 shows the sample state before and after aging of the sample prepared in Example 2 (adding 1.0 part RD and 1.0 part MB) in the performance test of this application;

[0034] FIG4 shows the sample state before and after aging of the sample prepared in Example 3 (adding 2.0 parts of RD and 2.0 parts of MB) in the performance test of this application;

[0035] FIG5 shows the sample state before and after aging of the sample prepared in Comparative Example 1 (adding 1.0 part of RD) in the performance test of this application;

[0036] FIG6 shows the sample state before and after aging of the sample prepared in Comparative Example 2 (adding 1.0 part MB) in the performance test of this application;

[0037] FIG7 shows the sample state before and after aging of the sample prepared in Comparative Example 3 (adding 2.5 parts of RD and 2.5 parts of MB) in the performance test of this application. DETAILED DESCRIPTION

[0038] The present application will be further described below in conjunction with the accompanying drawings and specific embodiments so that those skilled in the art can better understand the present application and implement it, but the embodiments are not intended to limit the present application.

[0039] Example 1

[0040] This embodiment provides an insulation material for a power cable of a wind turbine generator set, which comprises the following components in parts by weight:

[0041] Table 1

[0042] The preparation method of the insulation material of the power cable of the wind turbine generator set is as follows:

[0043] 1) 50 parts of the EPDM rubber were mixed in an internal mixer at 90° C. to 110° C. for 2 minutes until the mixing was uniform.

[0044] 2) 18 parts of 1250 mesh talc, 35 parts of modified calcined kaolin (primarily composed of silicon oxide and aluminum oxide; purchased from Shanghai Yichenhong Industrial Co., Ltd., material designation JP220), 2.5 parts of nano-zinc oxide, 3.0 parts of microcrystalline wax, 1.5 parts of titanium dioxide, 0.8 parts of stearic acid, 1.5 parts of antioxidant RD, 1.5 parts of antioxidant MB, 1.5 parts of antioxidant XH-3, 6.0 parts of paraffin oil, and coupling agent A-172 were added to the internal mixer and mixed for 3 minutes. Antioxidants RD, MB, and XH-3 are compounded to improve the overall heat resistance of the insulation.

[0045] 3) Finally, 2.0 parts of the vulcanizing agent dicumyl peroxide (DCP) and 1.5 parts of TAIC (triallyl isocyanurate) were added to the internal mixer, mixed for 1.5 minutes, and then the mixed rubber material was discharged.

[0046] 4) The mixed rubber material is thinned twice on an open mill and the rubber is swung three times, and then the rubber sheet is cut into sheets on a three-roll calender. The output rubber sheet is cooled by a cooling roller and passed through a talcum powder box to obtain a finished product.

[0047] Example 2

[0048] This embodiment provides an insulation material for a power cable of a wind turbine generator set, and its components are similar to those of Example 1, except that 1 part of antioxidant RD and 1 part of antioxidant MB are added to the components of the insulation material.

[0049] Example 3

[0050] This embodiment provides an insulation material for a power cable of a wind turbine generator set. The composition of the insulation material is similar to that of Example 1, except that 2 parts of antioxidant RD and 2 parts of antioxidant MB are added to the insulation material.

[0051] Comparative Example 1

[0052] This comparative example provides a wind turbine generator power cable, the components of which are similar to those of Example 1, except that 1 part of antioxidant RD is added to the insulating material components, and no antioxidant MB is added.

[0053] Comparative Example 2

[0054] This comparative example provides a wind turbine generator power cable, the components of which are similar to those of Example 1, except that 1 part of antioxidant MB is added to the insulating material components, and no antioxidant RD is added.

[0055] Comparative Example 3

[0056] This comparative example provides a wind turbine generator power cable, the components of which are similar to those of Example 1, except that 2.5 parts of antioxidant RD and 2.5 parts of antioxidant MB are added to the insulating material.

[0057] Performance Testing

[0058] (1) The insulating materials prepared in Examples 1-3 and Comparative Examples 1-3 were subjected to strength and elongation at break tests (GB / T 2951.12-2008) before and after aging. The results are shown in Table 2 and Figures 2-4:

[0059] Table 2

[0060] As can be seen from Table 3 and Figure 2-7, the 125°C operating temperature cable insulation formula uses EPDM raw rubber as the base material. EPDM raw rubber itself has excellent anti-aging properties. However, antioxidants must be added during the insulation production process to improve high-temperature aging resistance and service life. Antioxidant MB is a typical non-polluting antioxidant with excellent protection against thermal oxidative aging and climate aging. However, in actual use, it was found that when antioxidant MB was used alone, the insulation samples would turn brown and become brittle during aging. Consider adding antioxidant RD in combination. Antioxidant RD is a general-purpose amine rubber antioxidant with significant protection against thermal oxidative aging. However, when antioxidant RD was used alone, the elongation change rate during thermal aging would be too large. Therefore, the combination of antioxidant RD and antioxidant MB was ultimately chosen to improve the thermal aging performance of the rubber material. The above experimental data shows that when antioxidant RD and antioxidant RB each account for 1.0 to 2.0 parts, the strength, elongation, and aging performance of the insulation material are optimal. The aging test at 158℃ for 7 days proves that the insulation performance of this application is qualified at a working temperature of 125℃.

[0061] (2) The cable in this test example was prepared using the insulating material prepared in Example 1. The resulting cable was tested for current carrying capacity by TICW15-2012 "National Wire and Cable Quality Supervision and Inspection Center Technical Specifications Single Cable Air Laying Current Carrying Capacity Test Method", and the specific results are shown in Tables 3 and 4 below, where Table 3 is the current carrying capacity specified in the standard.

[0062] Table 3

[0063] Table 4

[0064] It can be seen from Tables 3 and 4 that the current carrying capacity can be increased by more than 20% while ensuring that the cable structure size and weight remain unchanged.

[0065] Obviously, the above embodiments are merely examples for clarity of explanation and are not intended to limit the implementation methods. Those skilled in the art will appreciate that other variations or modifications can be made based on the above description. It is not necessary and impossible to enumerate all implementation methods here. Obvious variations or modifications arising therefrom remain within the scope of protection of this application.

Claims

1. An insulating material for a low-voltage wind turbine power cable, wherein: By weight, it includes the following components:

2. The insulating material according to claim 1, wherein The antioxidants are antioxidant RD, antioxidant MB and antioxidant XH-3; the mass ratio of the antioxidant RD to the antioxidant MB is 1:

1.

3. The insulating material according to claim 2, wherein: The antioxidant RD is 1.0-2.0 parts; the antioxidant MB is 1.0-2.0 parts.

4. The insulating material according to claim 1, wherein The talcum powder is selected from talcum powder 1250 mesh.

5. The insulating material according to claim 1, wherein The vulcanizing agent is selected from DCP.

6. The insulating material according to claim 1, wherein The coupling agent is selected from coupling agent A-172.

7. The insulating material according to claim 1, wherein The vulcanization aid is selected from triallyl isocyanurate.

8. A method for preparing an insulating material for a low-voltage wind turbine power cable, comprising the following steps: 1) mixing the EPDM rubber uniformly in an internal mixer; 2) adding talcum powder, modified calcined kaolin, nano zinc oxide, microcrystalline wax, titanium dioxide, stearic acid, antioxidant, paraffin oil and coupling agent to the mixture obtained in step 1), and mixing in an internal mixer for 2-3 minutes; 3) adding a vulcanizing agent and a vulcanizing aid to the mixture obtained in step 2), and mixing in an internal mixer for 0.5 min to 1.5 min to obtain a mixed rubber material; 4) The mixed rubber material obtained in step 3) is thinly passed through an open mixer for 1-2 times, and the rubber is swung for 2-3 times, and then cut into strips and passed through a talcum powder box to obtain the insulation material for the low-voltage wind turbine power cable.

9. The preparation method according to claim 8, wherein: In step 1), the mixing conditions are: mixing at 90° C.-110° C. for 2 min-3 min.

10. A low-voltage wind turbine power cable, comprising a conductor, an insulating layer and an outer sheath; the insulating layer is made of the insulating material according to any one of claims 1 to 7.

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