JP2021111548A

JP2021111548A - Electric field relaxing material

Info

Publication number: JP2021111548A
Application number: JP2020003510A
Authority: JP
Inventors: 宏光平井; Hiromitsu Hirai; 徹志岡本; Tetsushi Okamoto; 智博竪山; Tomohiro Tateyama; 顕一山崎; Kenichi Yamazaki; 洋静垂井; Hiroyasu Tarui
Original assignee: Toshiba Corp; Toshiba Energy Systems and Solutions Corp
Current assignee: Toshiba Corp; Toshiba Energy Systems and Solutions Corp
Priority date: 2020-01-14
Filing date: 2020-01-14
Publication date: 2021-08-02

Abstract

To provide an electric field relaxing material that prevents electric field relaxing properties from deteriorating due to application of a high-frequency voltage.SOLUTION: An electric field relaxing material has a resin, and particles dispersed in the resin. The particle includes nonlinear resistant particles having nonlinear resistant properties to an electric field, and high dielectric constant particles.SELECTED DRAWING: Figure 1

Description

本発明の実施形態は、電界緩和材料に関する。 Embodiments of the present invention relate to electric field relaxation materials.

電界緩和材料は、電力機器における高電界部位の電界を緩和するために使用されている。例えば、回転機固定子コイルにおいては、炭化ケイ素（ＳｉｌｉｃｏｎＣａｒｂｉｄｅ：以下、「ＳｉＣ」と略記する。）粒子を樹脂中に分散させた塗料状の電界緩和材料を所定の位置に塗布して、電界緩和材料からなる領域を形成している。ＳｉＣ粒子は、電界が高くなるにつれて非線形に抵抗が小さくなる特性を持っている。 Electric field relaxation materials are used to relax the electric field at high field sites in electric power equipment. For example, in a rotating machine stator coil, a paint-like electric field easing material in which silicon carbide (hereinafter abbreviated as “SiC”) particles are dispersed in a resin is applied to a predetermined position to generate an electric field. It forms an area of relaxation material. The SiC particles have the property that the resistance decreases non-linearly as the electric field increases.

従来、電力機器を運転する際には、商用電源として供給されている周波数５０Ｈｚあるいは６０Ｈｚの交流電圧を印加していた。しかし、近年、電力機器の高効率化を目的として、インバータ駆動といった技術により、電力機器にこれまで想定されていなかった高周波数の電圧が印加される機会が増えてきている。 Conventionally, when operating an electric power device, an AC voltage having a frequency of 50 Hz or 60 Hz, which is supplied as a commercial power source, has been applied. However, in recent years, for the purpose of improving the efficiency of electric power equipment, there are increasing opportunities to apply a high frequency voltage, which has not been expected so far, to the electric power equipment by a technique such as inverter drive.

電力機器に使用される電界緩和材料においては、従来、電力機器に周波数５０Ｈｚあるいは６０Ｈｚの交流電圧が印加されることを想定して特性が検討されてきた。このため、電界緩和材料からなる領域を有する電力機器に、高周波数の電圧が印加されると、電界緩和材料による電界を緩和する効果が十分に得られない場合があった。 Conventionally, the characteristics of electric field relaxation materials used in electric power equipment have been studied on the assumption that an AC voltage having a frequency of 50 Hz or 60 Hz is applied to the electric power equipment. Therefore, when a high frequency voltage is applied to a power device having a region made of an electric field relaxing material, the effect of relaxing the electric field by the electric field relaxing material may not be sufficiently obtained.

特許第４６９０７９７号公報Japanese Patent No. 4690797

岡本徹志，河原誠，山田利光，井上良之，中村修平：「２粒子系複合体のパーコレーション現象と電界緩和材料の開発」，電学論Ａ，Vol.126，No.10，pp.1004-1012 (2006)Tetsushi Okamoto, Makoto Kawahara, Toshimitsu Yamada, Yoshiyuki Inoue, Shuhei Nakamura: "Percolation Phenomena of Two-Particle Composites and Development of Electric Field Relaxation Materials", Institute of Electrical Engineers of Japan A, Vol.126, No.10, pp.1004-1012 (2006) 中村隆央，熊田亜紀子，池田久利，日高邦彦，Steven A. Boggs，坪井雄一，木崎原智仁，櫻井隆幸，吉満哲夫：「繰り返しインパルス印加時のモータコイルにおける電界緩和層の電位分布および温度分布」，電気学会論文誌Ａ，Vol.135，No.2，pp.100-106 (2015)Takao Nakamura, Akiko Kumada, Kuri Ikeda, Kunihiko Hidaka, Steven A. Boggs, Yuichi Tsuboi, Tomohito Kizakihara, Takayuki Sakurai, Tetsuo Yoshimitsu: "Potential distribution and temperature distribution of the electric field relaxation layer in the motor coil when repeated impulses are applied" , IEEJ Transactions A, Vol.135, No.2, pp.100-106 (2015)

本発明が解決しようとする課題は、高周波数の電圧が印加されることによる電界緩和特性の低下が生じにくい電界緩和材料を提供することである。 An object to be solved by the present invention is to provide an electric field relaxation material in which the electric field relaxation characteristics are less likely to be deteriorated due to the application of a high frequency voltage.

実施形態の電界緩和材料は、樹脂と、樹脂中に分散された粒子とを持つ。粒子が、電界に対して非線形抵抗特性を有する非線形抵抗粒子と、高誘電率粒子とを含む。 The electric field relaxation material of the embodiment has a resin and particles dispersed in the resin. The particles include non-linear resistance particles having non-linear resistance characteristics to an electric field and high dielectric constant particles.

本実施形態の電界緩和材料を説明するための模式図。The schematic diagram for demonstrating the electric field relaxation material of this embodiment. 本実施形態の電界緩和材料からなる領域を有する電力機器の一例における回路。A circuit in an example of an electric power device having a region made of an electric field relaxation material of the present embodiment. 本実施形態の電界緩和材料からなる領域を有する電力機器モデルの例を示した概略断面図。FIG. 6 is a schematic cross-sectional view showing an example of an electric power equipment model having a region made of an electric field relaxation material of the present embodiment. 図３に示す電力機器モデルにおける電極の端面からの距離Ｌと電界緩和材料からなる領域の表面電位との関係を示したグラフ。FIG. 3 is a graph showing the relationship between the distance L from the end face of the electrode and the surface potential of the region made of the electric field relaxation material in the electric power equipment model shown in FIG. 本実施形態の電界緩和材料の一例における電界と比誘電率との関係を示したグラフ。The graph which showed the relationship between the electric field and the relative permittivity in an example of the electric field relaxation material of this embodiment.

以下、実施形態の電界緩和材料を、図面を参照して説明する。 Hereinafter, the electric field relaxation material of the embodiment will be described with reference to the drawings.

図１は、本実施形態の電界緩和材料を説明するための模式図である。図１に示すように、本実施形態の電界緩和材料４は、バインダー（特許請求の範囲における「樹脂」に相当する）２と、バインダー２中に分散された粒子とを含む。粒子は、電界に対して非線形抵抗特性を有する非線形抵抗粒子１と、高誘電率粒子３とを含む。 FIG. 1 is a schematic view for explaining the electric field relaxation material of the present embodiment. As shown in FIG. 1, the electric field relaxation material 4 of the present embodiment includes a binder (corresponding to "resin" in the claims) 2 and particles dispersed in the binder 2. The particles include non-linear resistance particles 1 having non-linear resistance characteristics with respect to an electric field, and high dielectric constant particles 3.

バインダー２としては、例えば、エポキシ樹脂、ポリアミド樹脂、ウレタン樹脂、ポリイミド樹脂などから選ばれる１種または２種以上の樹脂を用いることができる。 As the binder 2, for example, one kind or two or more kinds of resins selected from epoxy resin, polyamide resin, urethane resin, polyimide resin and the like can be used.

非線形抵抗粒子１は、電界に対して非線形抵抗特性を有する材料からなる粒子であればよく、電界が高くなるにつれて非線形に抵抗が小さくなる特性を有するものを用いることが好ましい。この場合、非線形抵抗粒子１の非線形抵抗特性によって、電界緩和効果がより効果的に得られる電界緩和材料４となる。電界が高くなるにつれて非線形に抵抗が小さくなる特性を有する非線形抵抗粒子１としては、例えば、ＳｉＣ、ＺｎＯなどからなる粒子が挙げられる。非線形抵抗粒子１は、１種類の粒子のみであってもよいし、２種以上の粒子であってもよい。 The non-linear resistance particle 1 may be a particle made of a material having a non-linear resistance characteristic with respect to an electric field, and it is preferable to use a particle having a characteristic that the resistance decreases non-linearly as the electric field increases. In this case, the non-linear resistance characteristic of the non-linear resistance particle 1 makes the electric field relaxation material 4 more effective in obtaining the electric field relaxation effect. Examples of the non-linear resistance particle 1 having a characteristic that the resistance decreases non-linearly as the electric field increases include particles made of SiC, ZnO, and the like. The nonlinear resistance particle 1 may be only one kind of particle or two or more kinds of particles.

非線形抵抗粒子１の形状は、特に限定されるものではなく、例えば、略球状であってもよいし、不定形であってもよい。また、非線形抵抗粒子１の粒径は、均一であってもよいし、不均一であってもよい。非線形抵抗粒子１の粒径は、例えば、動的光散乱法、レーザー回折法、遠心沈降法により測定できる。 The shape of the nonlinear resistance particle 1 is not particularly limited, and may be, for example, substantially spherical or irregular. Further, the particle size of the nonlinear resistance particles 1 may be uniform or non-uniform. The particle size of the nonlinear resistance particles 1 can be measured by, for example, a dynamic light scattering method, a laser diffraction method, or a centrifugal sedimentation method.

高誘電率粒子３としては、−５℃から１５５℃での比誘電率が５以上である高誘電率材料を用いることが好ましく、１０以上である高誘電率材料を用いることがより好ましい。このような材料としては、具体的には、Ｍｇ_２ＳｉＯ_４、Ａｌ_２Ｏ_３、ＭｇＴｉＯ_２、ＺｎＴｉＯ_３、Ｚｎ_２ＴｉＯ_４、ＴｉＯ_２、ＣａＴｉＯ_３、ＳｒＴｉＯ_３、ＢａＴｉＯ_３、ＳｒＺｒＯ_３、ＢａＴｉ_２Ｏ_５、ＢａＴｉ_４Ｏ_９、Ｂａ_２Ｔｉ_９Ｏ_２０、Ｂａ_２（Ｔｉ，Ｓｎ）_９Ｏ_２０、ＺｒＴｉＯ_４、（Ｚｒ，Ｓｒ）ＴｉＯ_４、ＢａＮｄ_２Ｔｉ_５Ｏ_１４、ＢａＳｍ_２ＴｉＯ_１４、Ｂｉ_２Ｏ_３ＢａＯＮｄ_２Ｏ_３ＴｉＯ_２、（Ｂｉ_２Ｏ_３，ＰｂＯ）ＢａＯＮｄ_２Ｏ_３ＴｉＯ_２、Ｌａ_２Ｔｉ_２Ｏ_７、Ｎｄ_２Ｔｉ_２Ｏ_７、（Ｌｉ，Ｓｍ）ＴｉＯ_３、Ｂａ（Ｍｇ_１／３Ｔａ_２／３）Ｏ_３、Ｂａ（Ｚｎ_１／３Ｔａ_２／３）Ｏ_３、Ｂａ（Ｚｎ_１／３Ｎｄ_２／３）Ｏ_３、Ｓｒ（Ｚｎ_１／３Ｎｄ_２／３）Ｏ_３などが挙げられる。高誘電率粒子３は、１種類の粒子のみであってもよいし、２種以上の粒子であってもよい。 As the high dielectric constant particles 3, it is preferable to use a high dielectric constant material having a relative permittivity of 5 or more at −5 ° C. to 155 ° C., and more preferably to use a high dielectric constant material having a relative dielectric constant of 10 or more. Such materials, _{_{_{_{specifically, Mg 2 SiO 4, Al 2}}}} O 3, MgTiO 2, ZnTiO 3, Zn 2 TiO 4, TiO 2, CaTiO 3, SrTiO 3, BaTiO 3, SrZrO 3, BaTi 2 _{_{_{O 5, BaTi 4 O 9,}}} Ba 2 Ti 9 O 20, Ba 2 (Ti, Sn) 9 O 20, ZrTiO 4, (Zr, Sr) TiO 4, BaNd 2 Ti 5 O 14, BaSm 2 TiO 14, Bi ₂ O ₃ BaONd ₂ O ₃ TiO ₂ , (Bi ₂ O ₃ , PbO) BaONd ₂ O ₃ TiO ₂ , La ₂ Ti ₂ O ₇ , Nd ₂ Ti ₂ O ₇ , (Li, Sm) TiO ₃ , Ba (Mg) _1/3 Ta _2/3 ) O ₃ , Ba (Zn _1/3 Ta _2/3 ) O ₃ , Ba (Zn _1/3 Nd _2/3 ) O ₃ , Sr (Zn _1/3 Nd _2/3 ) O _{3 and the} like can be mentioned. The high dielectric constant particles 3 may be only one kind of particles or two or more kinds of particles.

高誘電率粒子３は、高誘電率材料からなるものであればよい。高誘電率粒子３としては、電界に対して線形の誘電率特性を有する材料からなる粒子のみを用いてもよいし、電界に対して非線形の誘電率特性を有する材料からなる粒子のみを用いてもよいし、電界に対して線形の誘電率特性を有する材料からなる粒子と電界に対して非線形の誘電率特性を有する材料からなる粒子の両方を用いてもよい。 The high dielectric constant particles 3 may be made of a high dielectric constant material. As the high dielectric constant particles 3, only particles made of a material having a dielectric constant characteristic linear with respect to the electric field may be used, or only particles made of a material having a dielectric constant characteristic non-linear with respect to the electric field may be used. Alternatively, both particles made of a material having a dielectric constant characteristic linear with respect to the electric field and particles made of a material having a dielectric constant characteristic non-linear with respect to the electric field may be used.

本実施形態においては、高誘電率粒子３の一部または全部が、電界に対して非線形の誘電率特性を有することが好ましい。電界に対して非線形の誘電率特性を有する材料としては、電界が高くなるにつれて非線形に誘電率が上昇する特性を有するものを用いることが好ましい。このような特性を有する材料としては、例えば、ＳｒＴｉＯ_３、ＢａＴｉＯ_３、ＣａＴｉＯ_３などが挙げられる。 In the present embodiment, it is preferable that a part or all of the high dielectric constant particles 3 have a dielectric constant characteristic that is non-linear with respect to the electric field. As the material having a non-linear dielectric constant characteristic with respect to the electric field, it is preferable to use a material having a characteristic that the dielectric constant increases non-linearly as the electric field increases. Examples of the material having such characteristics include SrTiO ₃ , BaTiO ₃ , CaTiO _{3, and the} like.

電界緩和材料４が、電界が高くなるにつれて非線形に誘電率が上昇する特性を有する材料からなる粒子を含む高誘電率粒子３を含む場合、以下に示す（１）および（２）の効果が得られる。
（１）サージ電圧などの高周波かつ高電圧の電源が電界緩和材料４に供給された場合の効果。
この場合、高誘電率粒子３の誘電率が上昇するので、電界緩和材料４の誘電率がより高くなる。したがって、高誘電率粒子３を含むことによる電界緩和材料４と異なる部分での電位降下を防止する効果がより顕著となる。その結果、電界緩和材料４による電界緩和効果がより効果的に発揮される。 When the electric field relaxation material 4 includes high dielectric constant particles 3 including particles made of a material having a property that the dielectric constant increases non-linearly as the electric field increases, the effects of (1) and (2) shown below are obtained. Be done.
(1) Effect when a high-frequency and high-voltage power source such as a surge voltage is supplied to the electric field relaxation material 4.
In this case, since the dielectric constant of the high dielectric constant particles 3 increases, the dielectric constant of the electric field relaxation material 4 becomes higher. Therefore, the effect of preventing the potential drop at a portion different from the electric field relaxation material 4 due to the inclusion of the high dielectric constant particles 3 becomes more remarkable. As a result, the electric field relaxation effect of the electric field relaxation material 4 is more effectively exhibited.

（２）商用電源として供給されている周波数５０Ｈｚあるいは６０Ｈｚの交流電圧が電界緩和材料４に印加されているときの効果。
このとき、高誘電率粒子３の誘電率は低い状態であるので、電界緩和材料４の誘電率が高くなりすぎることが抑制される。このため、電界緩和材料４の周囲が、長期的に高い電界ストレスを受けることを防止できる。
なお、周波数５０Ｈｚあるいは６０Ｈｚの交流電圧が電界緩和材料４に印加されている状態であるときの電界緩和材料４の誘電率が高すぎると、電界緩和材料４の周囲の電界が高くなる。その結果、電界緩和材料４の周囲が、長期的に高い電界ストレスを受ける恐れがある。 (2) Effect when an AC voltage having a frequency of 50 Hz or 60 Hz supplied as a commercial power source is applied to the electric field relaxation material 4.
At this time, since the dielectric constant of the high dielectric constant particles 3 is in a low state, it is suppressed that the dielectric constant of the electric field relaxation material 4 becomes too high. Therefore, it is possible to prevent the periphery of the electric field relaxation material 4 from being subjected to high electric field stress for a long period of time.
If the dielectric constant of the electric field relaxation material 4 is too high when an AC voltage having a frequency of 50 Hz or 60 Hz is applied to the electric field relaxation material 4, the electric field around the electric field relaxation material 4 becomes high. As a result, the periphery of the electric field relaxation material 4 may be subjected to high electric field stress in the long term.

高誘電率粒子３の形状は、特に限定されるものではなく、例えば、略球状であってもよいし、不定形であってもよい。また、高誘電率粒子３の粒径は、均一であってもよいし、不均一であってもよい。高誘電率粒子３の粒径は、例えば、動的光散乱法、レーザー回折法、遠心沈降法により測定できる。 The shape of the high dielectric constant particles 3 is not particularly limited, and may be, for example, substantially spherical or irregular. Further, the particle size of the high dielectric constant particles 3 may be uniform or non-uniform. The particle size of the high dielectric constant particles 3 can be measured by, for example, a dynamic light scattering method, a laser diffraction method, or a centrifugal sedimentation method.

本実施形態の電界緩和材料４においては、高誘電率粒子３の平均粒径が、非線形抵抗粒子１の平均粒径以下であることが好ましい。この場合、バインダー２中において、高誘電率粒子３が非線形抵抗粒子１同士の接触を阻害しにくいものとなる。
本実施形態の電界緩和材料４においては、高誘電率粒子３の平均粒径１に対して、非線形抵抗粒子１の平均粒径が、２．５以上であることが好ましい。この場合、非線形抵抗粒子１同士の接触による電気的導電パスがより一層形成されやすくなる。 In the electric field relaxation material 4 of the present embodiment, the average particle size of the high dielectric constant particles 3 is preferably equal to or less than the average particle size of the nonlinear resistance particles 1. In this case, in the binder 2, the high dielectric constant particles 3 are less likely to inhibit the contact between the nonlinear resistance particles 1.
In the electric field relaxation material 4 of the present embodiment, the average particle size of the nonlinear resistance particles 1 is preferably 2.5 or more with respect to the average particle size 1 of the high dielectric constant particles 3. In this case, an electrically conductive path due to contact between the nonlinear resistance particles 1 is more likely to be formed.

本実施形態の電界緩和材料４においては、非線形抵抗粒子１の体積比率が３０体積％以上であり、かつ高誘電率粒子３の体積比率が非線形抵抗粒子１の体積比率以下であることが好ましい。
電界緩和材料４中に含まれる非線形抵抗粒子１の体積比率が３０体積％以上であると、バインダー２中において、非線形抵抗粒子１同士の接触による電気的導電パスが形成されやすくなる。
電界緩和材料４全体の体積中に含まれる非線形抵抗粒子１の体積比率は、３５体積％以上であることがより好ましく、４０体積％以上であることがさらに好ましい。この場合、非線形抵抗粒子１同士の接触による電気的導電パスがより一層形成されやすくなるとともに、非線形抵抗粒子１同士の接触による電気的導電パスが電界緩和材料４全体に均一に形成されやすくなる。 In the electric field relaxation material 4 of the present embodiment, it is preferable that the volume ratio of the nonlinear resistance particles 1 is 30% by volume or more and the volume ratio of the high dielectric constant particles 3 is equal to or less than the volume ratio of the nonlinear resistance particles 1.
When the volume ratio of the nonlinear resistance particles 1 contained in the electric field relaxation material 4 is 30% by volume or more, an electrically conductive path due to contact between the nonlinear resistance particles 1 is likely to be formed in the binder 2.
The volume ratio of the nonlinear resistance particles 1 contained in the total volume of the electric field relaxation material 4 is more preferably 35% by volume or more, further preferably 40% by volume or more. In this case, the electrically conductive path due to the contact between the nonlinear resistance particles 1 is more likely to be formed, and the electrically conductive path due to the contact between the nonlinear resistance particles 1 is more likely to be uniformly formed in the entire electric field relaxation material 4.

電界緩和材料４全体の体積中に含まれる高誘電率粒子３の体積比率が、非線形抵抗粒子１の体積比率以下であると、バインダー２中において、高誘電率粒子３が非線形抵抗粒子１同士の接触を阻害しにくいものとなる。
電界緩和材料４全体の体積中に含まれる高誘電率粒子３の体積比率と、非線形抵抗粒子１の体積比率との比（高誘電率粒子３：非線形抵抗粒子１）は、１：１．５〜１：８．０の範囲であることが好ましく、１：６〜１：２の範囲であることがより好ましい。上記の比が１：１．５〜１：８．０の範囲であると、非線形抵抗粒子１同士の接触による電気的導電パスがより一層形成されやすくなるとともに、非線形抵抗粒子１同士の接触による電気的導電パスが電界緩和材料４全体に均一に形成されやすくなる。 When the volume ratio of the high dielectric constant particles 3 contained in the entire volume of the electric field relaxation material 4 is equal to or less than the volume ratio of the non-linear resistance particles 1, the high dielectric constant particles 3 are among the non-linear resistance particles 1 in the binder 2. It becomes difficult to obstruct contact.
The ratio of the volume ratio of the high dielectric constant particles 3 contained in the entire volume of the electric field relaxation material 4 to the volume ratio of the non-linear resistance particles 1 (high dielectric constant particles 3: non-linear resistance particles 1) is 1: 1.5. The range is preferably in the range of ~ 1: 8.0, and more preferably in the range of 1: 6 to 1: 2. When the above ratio is in the range of 1: 1.5 to 1: 8.0, the electrically conductive path due to the contact between the nonlinear resistance particles 1 is more likely to be formed, and the contact between the nonlinear resistance particles 1 makes it easier to form. The electrically conductive path is likely to be uniformly formed in the entire electric field relaxation material 4.

電界緩和材料４全体の体積中に含まれる非線形抵抗粒子１と高誘電率粒子３の合計の体積は、７０体積％以下であることが好ましい。非線形抵抗粒子１と高誘電率粒子３の合計の体積が、７０体積％以下であると、電界緩和材料４が、未硬化（硬化前）のバインダー２中に粒子が分散された組成物の状態であるときに、塗料として取扱いしやすい粘度に調製しやすい。しかも、上記組成物を被形成面に塗布して硬化させることにより、被形成面に十分な強度で付着した硬化物からなる塗膜が得られやすい。
本明細書において、電界緩和材料４全体の体積とは、非線形抵抗粒子１と、高誘電率粒子３と、バインダー２の体積の総和を意味する。 The total volume of the nonlinear resistance particles 1 and the high dielectric constant particles 3 contained in the total volume of the electric field relaxation material 4 is preferably 70% by volume or less. When the total volume of the non-linear resistance particles 1 and the high dielectric constant particles 3 is 70% by volume or less, the electric field relaxation material 4 is in a state of a composition in which the particles are dispersed in the uncured (before curing) binder 2. When it is, it is easy to adjust the viscosity so that it can be easily handled as a paint. Moreover, by applying the above composition to the surface to be formed and curing it, it is easy to obtain a coating film made of a cured product that adheres to the surface to be formed with sufficient strength.
In the present specification, the volume of the entire electric field relaxation material 4 means the total volume of the nonlinear resistance particles 1, the high dielectric constant particles 3, and the binder 2.

本実施形態の電界緩和材料４は、室温での比誘電率が１０〜１０００の範囲内であることが好ましく、２０〜５００の範囲内であることがより好ましい。上記比誘電率が１０以上であると、電界緩和材料４の静電容量が大きいものとなる。このため、６０Ｈｚを超える高周波数の交流電圧が印加された場合においても、電界緩和材料４と異なる部分からの静電容量を介する電流の流れと電位降下が生じにくくなる。よって、電界緩和材料４による電界緩和効果が効果的に得られる。また、上記比誘電率が１０００以下であると、電界緩和材料４以外の高誘電率でない部分に電位が分担され、分担された部分の電界が高くなることによって生じる不具合を防止できる。 The electric field relaxation material 4 of the present embodiment preferably has a relative permittivity in the range of 10 to 1000 at room temperature, and more preferably in the range of 20 to 500. When the relative permittivity is 10 or more, the capacitance of the electric field relaxation material 4 becomes large. Therefore, even when an AC voltage having a high frequency exceeding 60 Hz is applied, a current flow and a potential drop through the capacitance from a portion different from the electric field relaxation material 4 are less likely to occur. Therefore, the electric field relaxation effect of the electric field relaxation material 4 can be effectively obtained. Further, when the relative permittivity is 1000 or less, the potential is shared by the portion other than the electric field relaxation material 4 which does not have a high dielectric constant, and it is possible to prevent a problem caused by an increase in the electric field of the shared portion.

電界緩和材料４は、未硬化（硬化前）のバインダー２中に粒子が分散された組成物の状態であってもよいし、未硬化のバインダー２と粒子とを含む組成物を硬化させた硬化物の状態であってもよい。電界緩和材料４が、未硬化のバインダー２中に粒子が分散された組成物の状態である場合、組成物中には、バインダー２と粒子の他に、必要に応じて溶媒が含まれていてもよい。溶媒としては、公知のものを用いることができ、バインダー２の種類などに応じて、適宜決定できる。 The electric field relaxation material 4 may be in a state of a composition in which particles are dispersed in an uncured (before curing) binder 2, or a cured composition containing the uncured binder 2 and particles is cured. It may be in the state of an object. When the electric field relaxation material 4 is in a state of a composition in which particles are dispersed in an uncured binder 2, the composition contains a solvent in addition to the binder 2 and particles, if necessary. May be good. As the solvent, a known solvent can be used and can be appropriately determined depending on the type of the binder 2 and the like.

次に、本実施形態の電界緩和材料４の製造方法について説明する。
本実施形態の電界緩和材料４は、例えば、未硬化（硬化前）のバインダー２と、非線形抵抗粒子１と、高誘電率粒子３と、必要に応じて含有される溶媒とを公知の方法により混合し、バインダー２中に非線形抵抗粒子１および高誘電率粒子３を分散させる方法により製造できる。このことにより、未硬化（硬化前）のバインダー２中に粒子が分散された組成物の状態の電界緩和材料４が得られる。バインダー２として、主剤と硬化剤とを混合して硬化させる２液混合タイプのものを使用する場合、非線形抵抗粒子１および高誘電率粒子３の含有量は、２液を混合した時点で所定の割合となるようにすればよい。したがって、バインダー２として２液混合タイプのものを使用する場合、非線形抵抗粒子１および高誘電率粒子３を、主剤および硬化剤にそれぞれ分散させてもよい。
組成物の状態の電界緩和材料４は、塗料として用いることができる。組成物の状態の電界緩和材料４は、公知の方法により被形成面に塗布して硬化させる方法により、硬化物である塗膜の状態とすることができる。 Next, a method for producing the electric field relaxation material 4 of the present embodiment will be described.
The electric field relaxation material 4 of the present embodiment contains, for example, an uncured (before curing) binder 2, non-curable resistance particles 1, high dielectric constant particles 3, and a solvent contained as needed by a known method. It can be produced by a method of mixing and dispersing the nonlinear resistance particles 1 and the high dielectric constant particles 3 in the binder 2. As a result, the electric field relaxation material 4 in the state of the composition in which the particles are dispersed in the uncured (before curing) binder 2 is obtained. When a two-component mixed type in which the main agent and the curing agent are mixed and cured is used as the binder 2, the contents of the nonlinear resistance particles 1 and the high dielectric constant particles 3 are predetermined when the two liquids are mixed. It should be a ratio. Therefore, when a two-component mixed type binder 2 is used, the nonlinear resistance particles 1 and the high dielectric constant particles 3 may be dispersed in the main agent and the curing agent, respectively.
The electric field relaxation material 4 in the state of the composition can be used as a paint. The electric field relaxation material 4 in the state of the composition can be made into a state of a coating film which is a cured product by a method of applying the electric field relaxation material 4 to the surface to be formed by a known method and curing the material.

本実施形態の電界緩和材料４は、電力機器における高電界部位の電界を緩和するために用いることができる。具体的には、例えば、電力機器の所定の位置に、組成物の状態の電界緩和材料４を塗布して硬化させる方法により用いることができる。
本実施形態の電界緩和材料４からなる領域が設けられる電力機器は、特に限定されないが、電界緩和材料４からなる領域と異なる部分に静電容量を有する電力機器であると、本実施形態の電界緩和材料４を用いることによる電界緩和効果が顕著となる。
本実施形態の電界緩和材料４からなる領域が設けられる電力機器としては、例えば、電力ケーブルの接続部およびスイッチギヤなどの円筒形状を有するものであってもよいし、回路素子およびバスバーなどの第１面に高圧電極が備えられ第２面に接地された電極が備えられた円盤形状を有するものであってもよいし、回転機固定子コイルなどであってもよく、特に限定されない。 The electric field relaxation material 4 of the present embodiment can be used to relax the electric field in the high electric field portion of the electric power device. Specifically, for example, it can be used by a method in which the electric field relaxation material 4 in the state of the composition is applied and cured at a predetermined position of the electric power device.
The electric power device provided with the region made of the electric field relaxation material 4 of the present embodiment is not particularly limited, but the electric field of the present embodiment is defined as a power device having a capacitance in a portion different from the region made of the electric field relaxation material 4. The electric field relaxation effect by using the relaxation material 4 becomes remarkable.
The electric power device provided with the region made of the electric field relaxation material 4 of the present embodiment may have a cylindrical shape such as a power cable connection portion and a switch gear, or may have a cylindrical shape such as a circuit element and a bus bar. It may have a disk shape having a high-voltage electrode provided on one surface and an electrode grounded on the second surface, or may be a rotary machine stator coil or the like, and is not particularly limited.

本実施形態の電界緩和材料４は、バインダー２と、バインダー２中に分散された粒子とを含み、粒子が、電界に対して非線形抵抗特性を有する非線形抵抗粒子１と、高誘電率粒子３とを含む。このため、本実施形態の電界緩和材料４は、高周波数の電圧が印加されることによる電界緩和特性の低下が生じにくい。 The electric field relaxation material 4 of the present embodiment includes a binder 2 and particles dispersed in the binder 2, and the particles include a non-linear resistance particle 1 having a non-linear resistance characteristic with respect to an electric field and a high dielectric constant particle 3. including. Therefore, the electric field relaxation material 4 of the present embodiment is unlikely to deteriorate in the electric field relaxation characteristics due to the application of a high frequency voltage.

より詳細には、本実施形態の電界緩和材料４は、高誘電率粒子３を含むため静電容量が大きい。このため、６０Ｈｚを超える高周波数の交流電圧が印加された場合においても、電界緩和材料４と異なる部分からの静電容量を介する電流の流れと電位降下が生じにくい。したがって、高周波数の電圧が印加されることによる電界緩和特性の低下が生じにくく、高周波数の電圧が印加されても電界緩和材料４による電界緩和効果が効果的に得られる。その結果、所定の位置に電界緩和材料４からなる領域が設けられた電力機器に、インバータ駆動などにより高周波数の電圧が印加された場合においても、電界緩和材料４による電界緩和効果が十分に得られ、電力機器を高電界から保護できる。 More specifically, the electric field relaxation material 4 of the present embodiment has a large capacitance because it contains high dielectric constant particles 3. Therefore, even when an AC voltage having a high frequency exceeding 60 Hz is applied, a current flow and a potential drop through the capacitance from a portion different from the electric field relaxation material 4 are unlikely to occur. Therefore, the electric field relaxation characteristics are less likely to deteriorate due to the application of the high frequency voltage, and the electric field relaxation effect of the electric field relaxation material 4 can be effectively obtained even when the high frequency voltage is applied. As a result, even when a high frequency voltage is applied to a power device provided with a region made of the electric field relaxation material 4 at a predetermined position by driving an inverter or the like, the electric field relaxation effect of the electric field relaxation material 4 can be sufficiently obtained. And can protect power equipment from high electric fields.

図２は、本実施形態の電界緩和材料からなる領域を有する電力機器の一例における回路である。図２において、符号２０は、本実施形態の電界緩和材料からなる領域の静電容量の等価回路を示している。図２に示す例における電界緩和材料からなる領域には、非線形抵抗と静電容量とが並列に配置され、それらが直列に４つ接続されている。また、符号２１は、電力機器の有する電界緩和材料からなる領域と異なる部分の静電容量の等価回路を示している。
図２に示す回路において、電源から高周波数の交流電圧が印加された場合、本実施形態の電界緩和材料４の静電容量が大きいため、等価回路２１に電流が流れにくく、等価回路２１での電位降下が生じにくい。 FIG. 2 is a circuit in an example of an electric power device having a region made of the electric field relaxation material of the present embodiment. In FIG. 2, reference numeral 20 indicates an equivalent circuit of capacitance in a region made of the electric field relaxation material of the present embodiment. In the region made of the electric field relaxation material in the example shown in FIG. 2, a nonlinear resistor and a capacitance are arranged in parallel, and four of them are connected in series. Further, reference numeral 21 indicates an equivalent circuit of capacitance in a portion different from the region made of the electric field relaxation material of the electric power device.
In the circuit shown in FIG. 2, when a high-frequency AC voltage is applied from the power source, the capacitance of the electric field relaxation material 4 of the present embodiment is large, so that it is difficult for current to flow through the equivalent circuit 21, and the equivalent circuit 21 Potential drop is unlikely to occur.

これに対し、例えば、本実施形態の電界緩和材料４に代えて、高誘電率粒子３を含まない電界緩和材料が用いられている場合、図２に示す回路において、電源から高周波数の交流電圧が印加されると、等価回路２１の静電容量に起因するインピーダンスが低下する。そのため、例えば、電源から周波数５０Ｈｚあるいは６０Ｈｚの交流電圧が印加されている場合と比較して、等価回路２１に電流が多く流れ、電位が急激に低下してしまう。その結果、電界緩和材料４からなる領域と異なる部分での電位降下が生じ、電界緩和材料４による電界緩和効果が得られにくくなる。 On the other hand, for example, when an electric field relaxation material that does not contain the high dielectric constant particles 3 is used instead of the electric field relaxation material 4 of the present embodiment, in the circuit shown in FIG. 2, a high frequency AC voltage is applied from the power source. Is applied, the impedance due to the capacitance of the equivalent circuit 21 decreases. Therefore, for example, as compared with the case where an AC voltage having a frequency of 50 Hz or 60 Hz is applied from the power source, a large amount of current flows through the equivalent circuit 21, and the potential drops sharply. As a result, a potential drop occurs in a portion different from the region made of the electric field relaxation material 4, and it becomes difficult to obtain the electric field relaxation effect of the electric field relaxation material 4.

本実施形態の電界緩和材料４において、高誘電率粒子３の平均粒径が、非線形抵抗粒子１の平均粒径以下である場合、バインダー２中において、高誘電率粒子３が非線形抵抗粒子１同士の接触を阻害しにくいものとなる。その結果、非線形抵抗粒子１同士の接触による電気的導電パスが形成されやすくなる。よって、非線形抵抗粒子１の非線形抵抗特性による電界緩和効果がより効果的に得られる電界緩和材料４となる。 In the electric field relaxation material 4 of the present embodiment, when the average particle size of the high dielectric constant particles 3 is equal to or less than the average particle size of the non-linear resistance particles 1, the high dielectric constant particles 3 are each other in the binder 2. It becomes difficult to obstruct the contact of the particles. As a result, an electrically conductive path is easily formed by the contact between the nonlinear resistance particles 1. Therefore, the electric field relaxation material 4 can more effectively obtain the electric field relaxation effect due to the nonlinear resistance characteristics of the nonlinear resistance particles 1.

本実施形態の電界緩和材料４において、非線形抵抗粒子１の体積比率が３０体積％以上であり、かつ高誘電率粒子３の体積比率が非線形抵抗粒子１の体積比率以下である場合、以下に示す効果が得られる。すなわち、電界緩和材料４全体の体積中に含まれる非線形抵抗粒子１の体積比率が３０体積％以上であるので、バインダー２中において、非線形抵抗粒子１同士の接触による電気的導電パスが形成されやすくなる。しかも、電界緩和材料４全体の体積中に含まれる高誘電率粒子３の体積比率が、非線形抵抗粒子１の体積比率以下であるので、バインダー２中において、高誘電率粒子３が非線形抵抗粒子１同士の接触を阻害しにくいものとなる。その結果、非線形抵抗粒子１同士の接触による電気的導電パスがより形成されやすくなる。したがって、非線形抵抗粒子１の非線形抵抗特性による効果がより効果的に得られる電界緩和材料４となる。 In the electric field relaxation material 4 of the present embodiment, when the volume ratio of the nonlinear resistance particles 1 is 30% by volume or more and the volume ratio of the high dielectric constant particles 3 is equal to or less than the volume ratio of the nonlinear resistance particles 1, it is shown below. The effect is obtained. That is, since the volume ratio of the nonlinear resistance particles 1 contained in the entire volume of the electric field relaxation material 4 is 30% by volume or more, an electrically conductive path is easily formed in the binder 2 due to the contact between the nonlinear resistance particles 1. Become. Moreover, since the volume ratio of the high dielectric constant particles 3 contained in the entire volume of the electric field relaxation material 4 is equal to or less than the volume ratio of the non-linear resistance particles 1, the high dielectric constant particles 3 are the non-linear resistance particles 1 in the binder 2. It becomes difficult to prevent contact between each other. As a result, an electrically conductive path due to contact between the nonlinear resistance particles 1 is more likely to be formed. Therefore, the electric field relaxation material 4 can more effectively obtain the effect of the non-linear resistance characteristic of the non-linear resistance particle 1.

本実施形態の電界緩和材料４が、室温（２７℃）での比誘電率が１０〜１０００の範囲内である場合、６０Ｈｚを超える高周波数の交流電圧が印加された場合においても、電界緩和材料４による電界緩和効果が効果的に得られる。しかも、電界緩和材料４以外の高誘電率でない部分に電位が分担され、分担された部分の電界が高くなることによって生じる不具合を防止できる。 When the electric field relaxation material 4 of the present embodiment has a relative permittivity in the range of 10 to 1000 at room temperature (27 ° C.), the electric field relaxation material even when a high frequency AC voltage exceeding 60 Hz is applied. The electric field relaxation effect of 4 can be effectively obtained. Moreover, it is possible to prevent a problem caused by the potential being shared by a portion other than the electric field relaxation material 4 having a non-high dielectric constant and the electric field of the shared portion being increased.

本実施形態の電界緩和材料４の電界緩和効果について、図３に示す電力機器モデルを用いて評価した。
図３は、本実施形態の電界緩和材料からなる領域を有する電力機器モデルの例を示した概略断面図である。 The electric field relaxation effect of the electric field relaxation material 4 of the present embodiment was evaluated using the electric power equipment model shown in FIG.
FIG. 3 is a schematic cross-sectional view showing an example of an electric power equipment model having a region made of the electric field relaxation material of the present embodiment.

図３に示す電力機器モデルは、円筒形状であり、中心に金属の丸棒電極６を有する。丸棒電極６の外周面は、樹脂７で覆われている。樹脂７の外周面には、リング状の２つの電極５１、５２が、５０ｍｍの間隔を空けて平行に設置されている。２つの電極５１、５２の間に配置されている樹脂７の外面には、電界緩和材料４からなる塗膜が形成されている。 The electric power equipment model shown in FIG. 3 has a cylindrical shape and has a metal round bar electrode 6 in the center. The outer peripheral surface of the round bar electrode 6 is covered with the resin 7. Two ring-shaped electrodes 51 and 52 are installed in parallel on the outer peripheral surface of the resin 7 with an interval of 50 mm. A coating film made of the electric field relaxation material 4 is formed on the outer surface of the resin 7 arranged between the two electrodes 51 and 52.

図３に示す電力機器モデルにおいて、丸棒電極６および電極５１に周波数１ｋＨｚ、電圧２０ｋＶの交流を印加し、電極５２を接地した。そして、比誘電率が５０、１００、１０００である電界緩和材料４からなる塗膜を形成した場合における、電極５１の端面からの距離Ｌに対する電界緩和材料４表面の表面電位をそれぞれ解析した。解析には、ＣＯＭＳＯＬＭｕｌｔｉｐｈｙｓｉｃｓ（ＣＯＭＳＯＬ社製）を用いた。その結果を図４に示す。 In the electric power equipment model shown in FIG. 3, an alternating current having a frequency of 1 kHz and a voltage of 20 kV was applied to the round bar electrode 6 and the electrode 51, and the electrode 52 was grounded. Then, when a coating film made of the electric field relaxation material 4 having a relative permittivity of 50, 100, 1000 was formed, the surface potential of the surface of the electric field relaxation material 4 with respect to the distance L from the end face of the electrode 51 was analyzed. For the analysis, COMSOL Multiphysics (manufactured by COMSOL) was used. The result is shown in FIG.

比誘電率が５０である電界緩和材料４からなる塗膜は、以下に示す方法により形成した。すなわち、エポキシ樹脂（商品名：主剤ｊＥＲ８２８（三菱ケミカル社製）、硬化剤ポリエーテルアミン（三井化学ファイン社製））からなるバインダー２と、平均粒径１４μｍのＳｉＣ粒子からなる非線形抵抗粒子１と、平均粒径１μｍのＢａＴｉＯ_３粒子からなる電界に対して非線形の誘電率特性を有する高誘電率粒子３とを、それぞれ所定量用意した。これらを混合して分散させることにより組成物とした。組成物中のバインダー２と非線形抵抗粒子１と高誘電率粒子３との体積比（バインダー２：非線形抵抗粒子１：高誘電率粒子３）は、４２：４０：１８とした。得られた組成物を２つの電極５１、５２間の樹脂７の外面に塗布して乾燥させることにより、膜厚約１ｍｍの塗膜を得た。 The coating film made of the electric field relaxation material 4 having a relative permittivity of 50 was formed by the method shown below. That is, a binder 2 made of an epoxy resin (trade name: main agent jER828 (manufactured by Mitsubishi Chemical Co., Ltd.) and a curing agent polyether amine (manufactured by Mitsui Chemical Fine Co., Ltd.)) and non-linear resistance particles 1 made of SiC particles having an average particle size of 14 μm. , High dielectric constant particles 3 having a dielectric constant characteristic that is non-linear with respect to an electric field composed _{of BaTiO 3} particles having an average particle diameter of 1 μm were prepared in predetermined amounts. These were mixed and dispersed to prepare a composition. The volume ratio of the binder 2, the non-linear resistance particles 1, and the high dielectric constant particles 3 in the composition (binder 2: non-linear resistance particles 1: high dielectric constant particles 3) was 42:40:18. The obtained composition was applied to the outer surface of the resin 7 between the two electrodes 51 and 52 and dried to obtain a coating film having a film thickness of about 1 mm.

また、上記と同様にして、比誘電率が４、１００、１０００である電界緩和材料からなる塗膜を形成した場合における、電極５１の端面からの距離Ｌに対する電界緩和材料表面の表面電位を解析した。その結果を図４に示す。 Further, in the same manner as described above, the surface potential of the surface of the electric field relaxing material with respect to the distance L from the end face of the electrode 51 when a coating film made of the electric field relaxing material having a relative permittivity of 4, 100, 1000 is formed is analyzed. did. The result is shown in FIG.

図４は、図３に示す電力機器モデルにおける電極の端面からの距離Ｌと電界緩和材料からなる領域の表面電位との関係を示したグラフである。
図４において、符号８は、電界緩和材料の比誘電率が４である場合の結果である。符号９は、電界緩和材料の比誘電率が５０である場合の結果である。符号１０は、電界緩和材料の比誘電率が１００である場合の結果である。符号１１は、電界緩和材料の比誘電率が１０００である場合の結果である。 FIG. 4 is a graph showing the relationship between the distance L from the end face of the electrode and the surface potential of the region made of the electric field relaxation material in the electric power equipment model shown in FIG.
In FIG. 4, reference numeral 8 is a result when the relative permittivity of the electric field relaxation material is 4. Reference numeral 9 is a result when the relative permittivity of the electric field relaxation material is 50. Reference numeral 10 is a result when the relative permittivity of the electric field relaxation material is 100. Reference numeral 11 is a result when the relative permittivity of the electric field relaxation material is 1000.

図４に示すように、電界緩和材料の比誘電率が５０、１００、１０００である場合、比誘電率が高いほど、高誘電率粒子３を含まない電界緩和材料の比誘電率が４である場合と比較して、電極５１の端面からの距離Ｌに対する表面電位の低下を示す傾斜が緩やかになっている。
これは、電界緩和材料の比誘電率が５０、１００、１０００である場合、１ｋＨｚの高周波数の電圧が印加されても、電界緩和材料と異なる部分からの静電容量（図３に示す電力機器モデルでは、樹脂７）を介する電流の流れと電位降下が生じにくく、電界緩和材料による電界緩和効果が効果的に得られたことによるものと推定される。 As shown in FIG. 4, when the relative permittivity of the electric field relaxation material is 50, 100, 1000, the higher the relative permittivity, the higher the relative permittivity of the electric field relaxation material containing no high dielectric constant particles 3. Compared with the case, the inclination indicating the decrease in the surface potential with respect to the distance L from the end face of the electrode 51 is gentle.
This is because when the relative permittivity of the electric field relaxation material is 50, 100, 1000, even if a high frequency voltage of 1 kHz is applied, the capacitance from a portion different from that of the electric field relaxation material (power equipment shown in FIG. 3). In the model, it is presumed that the current flow and potential drop through the resin 7) are unlikely to occur, and the electric field relaxation effect of the electric field relaxation material is effectively obtained.

また、図４に示すように、電界緩和材料４の比誘電率が１０００である場合、最も電界が低い場合の電極５１の端面からの距離Ｌに対する表面電位の低下を示す傾斜（直線）に近似する傾斜となった。このことから、電界緩和材料４の比誘電率が５０〜１０００である場合、電界緩和材料４による電界緩和効果が得られることが確認できた。 Further, as shown in FIG. 4, when the relative permittivity of the electric field relaxation material 4 is 1000, it is close to an inclination (straight line) indicating a decrease in the surface potential with respect to the distance L from the end face of the electrode 51 when the electric field is the lowest. It became a slope. From this, it was confirmed that the electric field relaxation effect of the electric field relaxation material 4 can be obtained when the relative permittivity of the electric field relaxation material 4 is 50 to 1000.

以下に示す方法により、試験体としての電界緩和材料４からなる塗膜を形成した。
すなわち、エポキシ樹脂（商品名：主剤ｊＥＲ８２８（三菱ケミカル社製）、硬化剤ポリエーテルアミン（三井化学ファイン社製））からなるバインダー２と、平均粒径１４μｍのＳｉＣ粒子からなる非線形抵抗粒子１と、平均粒径１μｍのＢａＴｉＯ_３粒子からなる電界に対して非線形の誘電率特性を有する高誘電率粒子３とを、それぞれ所定量用意した。これらを、硬化後の電界緩和材料４からなる塗膜に含まれる非線形抵抗粒子１が４０体積％、高誘電率粒子３が１８体積％、残部エポキシ樹脂となるように、混合して分散させることにより組成物とした。得られた組成物を厚みが１ｍｍとなるように塗布して乾燥させた。 A coating film made of the electric field relaxation material 4 as a test piece was formed by the method shown below.
That is, a binder 2 made of an epoxy resin (trade name: main agent jER828 (manufactured by Mitsubishi Chemical Co., Ltd.) and a curing agent polyether amine (manufactured by Mitsui Chemical Fine Co., Ltd.)) and non-linear resistance particles 1 made of SiC particles having an average particle size of 14 μm. , High dielectric constant particles 3 having a dielectric constant characteristic that is non-linear with respect to an electric field composed _{of BaTiO 3} particles having an average particle diameter of 1 μm were prepared in predetermined amounts. These are mixed and dispersed so that the non-linear resistance particles 1 contained in the coating film made of the electric field relaxation material 4 after curing are 40% by volume, the high dielectric constant particles 3 are 18% by volume, and the balance is an epoxy resin. To make a composition. The obtained composition was applied to a thickness of 1 mm and dried.

このようにして得られた電界緩和材料４からなる塗膜について、高圧アンプＨＡＰ−１０Ｂ４０（松定プレシジョン社製）、オシロスコープＤＰＯ７１０４（Ｔｅｋｔｒｏｎｉｘ社製）、高圧プローブＰ６０１５Ａ（Ｔｅｋｔｒｏｎｉｘ社製）を用いて、電界と比誘電率との関係を調べた。その結果を図５に示す。
図５は、本実施形態の電界緩和材料の一例における電界と比誘電率との関係を示したグラフである。図５に示すように、ＢａＴｉＯ_３粒子からなる高誘電率粒子３を含む電界緩和材料４は、電界が高くなるにつれて非線形に誘電率が上昇する特性を有することが確認できた。 The coating film made of the electric field relaxation material 4 thus obtained was used with a high-voltage amplifier HAP-10B40 (manufactured by Matsusada Precision), an oscilloscope DPO7104 (manufactured by Tektronix), and a high-voltage probe P6015A (manufactured by Tektronix). The relationship between the electric field and the relative permittivity was investigated. The result is shown in FIG.
FIG. 5 is a graph showing the relationship between the electric field and the relative permittivity in an example of the electric field relaxation material of the present embodiment. As shown in FIG. 5, it was confirmed that the electric field relaxation material 4 containing the high dielectric constant particles 3 composed of _{BaTiO 3 particles has a characteristic that the dielectric constant increases non-linearly as the electric field increases.}

以上説明した少なくともひとつの実施形態によれば、樹脂と、樹脂中に分散された粒子とを含み、粒子が、電界に対して非線形抵抗特性を有する非線形抵抗粒子と、高誘電率粒子とを含むことにより、高周波数の電圧が印加されることによる電界緩和特性の低下が生じにくい電界緩和材料を提供することができる。 According to at least one embodiment described above, the resin and the particles dispersed in the resin are included, and the particles include non-linear resistance particles having non-linear resistance characteristics to an electric field and high dielectric constant particles. This makes it possible to provide an electric field relaxation material in which the electric field relaxation characteristics are less likely to deteriorate due to the application of a high frequency voltage.

本発明のいくつかの実施形態を説明したが、これらの実施形態は、例として提示したものであり、発明の範囲を限定することは意図していない。これら実施形態は、その他の様々な形態で実施されることが可能であり、発明の要旨を逸脱しない範囲で、種々の省略、置き換え、変更を行うことができる。これら実施形態やその変形は、発明の範囲や要旨に含まれると同様に、特許請求の範囲に記載された発明とその均等の範囲に含まれるものである。 Although some embodiments of the present invention have been described, these embodiments are presented as examples and are not intended to limit the scope of the invention. These embodiments can be implemented in various other forms, and various omissions, replacements, and changes can be made without departing from the gist of the invention. These embodiments and modifications thereof are included in the scope and gist of the invention, as well as in the scope of the invention described in the claims and the equivalent scope thereof.

１…非線形抵抗粒子、２…バインダー、３…高誘電率粒子、４…電界緩和材料、６…丸棒電極、７…樹脂、２０、２１…等価回路、５１、５２…電極。 1 ... Non-linear resistance particle, 2 ... Binder, 3 ... High dielectric constant particle, 4 ... Electric field relaxation material, 6 ... Round bar electrode, 7 ... Resin, 20, 21 ... Equivalent circuit, 51, 52 ... Electrode.

Claims

It contains a resin and particles dispersed in the resin.
An electric field relaxation material in which the particles include non-linear resistance particles having non-linear resistance characteristics with respect to an electric field and high dielectric constant particles.

The electric field relaxation material according to claim 1, wherein the average particle size of the high dielectric constant particles is equal to or less than the average particle size of the nonlinear resistance particles.

The volume ratio of the nonlinear resistance particles is 30% by volume or more, and the volume ratio is 30% by volume or more.
The electric field relaxation material according to claim 1 or 2, wherein the volume ratio of the high dielectric constant particles is equal to or less than the volume ratio of the nonlinear resistance particles.

The electric field relaxation material according to any one of claims 1 to 3, wherein a part or all of the high dielectric constant particles have a dielectric constant characteristic that is non-linear with respect to an electric field.

The electric field relaxation material according to any one of claims 1 to 4, wherein the relative permittivity at 27 ° C. is in the range of 10 to 1000.