JPS60116105A - Voltage/current nonlinear resistor - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed Description of the Invention] [Technical Field of the Invention] The present invention relates to a voltage/current nonlinear resistor made of a sintered body containing zinc oxide (ZnO) as a main component, and which has particularly excellent life characteristics when DC current is applied. Concerning voltage-current nonlinear resistors.

[Technical background of the invention and its problems]

Various types of voltage/current non-direction resistors (varistors) have been polished in the past, and one of them uses a sintered body mainly composed of 1CZnO. This Z! In V, which uses a sintered body containing 10 as a main component, attempts have been made to add various subcomponents to obtain desired characteristics.

Recently, the development of DC power transmission has been carried out, but unlike in the case of intercurrent power transmission, a unidirectional electric field is always applied to a nonlinear resistor, resulting in extremely harsh conditions. Currently, a voltage-current nonlinear resistor with DC life characteristics that can withstand such harsh conditions has not been obtained. For example, ZnOvcH shown in JP-A-49-119188
120g, OoO, 8b203, Nip.

those with MnO added, those with B and Bi added to ZnO as shown in Japanese Patent Publication No. 19472/1972,
6-33842, in which a glass containing boron oxide is added to ZnO, etc., are known, but none of them have sufficient characteristics. For example, when DC voltage is applied, the leakage current increases over time, causing thermal runaway.
The DC life characteristics were poor.

In addition, as power transmission becomes more ultra-high voltage (UHV) in recent years, the required characteristics, such as acupuncture current non-direct characteristics and life characteristics, are becoming more severe.

As described above, the demand for improving the life characteristics, nonlinearity, and other performance characteristics is increasing year by year, and research is being conducted at various locations to satisfy these demands.

[Purpose of the invention]

The present invention has been made in consideration of the above points, and it is an object of the present invention to provide a non-direct-flow resistor with excellent DC life characteristics l/'C. A further object of the present invention is to provide a voltage/current nonlinear resistor having excellent voltage/current nonlinear characteristics.

[Summary of the invention]

The main component of the present invention is zinc oxide, and the subcomponents are bismuth, cobalt, manganese, antimony, and nickel, respectively.
Converted to 208゜NiO, Bi2O30,1--5mo1%, Oo20g 0
．． 1-5 mo1%.

Mn (J o, 1-5 moi 1%, 8b2030.
1-5tno1%.

Ni0 0.1-5 ma1% Furthermore, at least one selected from aluminum, indium, and gallium, or 0.0001-0.05 mai1% or less in terms of All, In, and Ga based on the basic composition contained. , boron is converted to B203VC and becomes 0
．． The present invention is a voltage/current nonlinear resistor characterized in that it is made of a sintered body in which glass containing boron is added in an amount of 0.001 to 1 wt%.

The above (B 1203, Co,, 03, 'M
By adopting a composition in which a glass containing B is added to a basic component containing nO, 5b203, NiO and at least one of A, g, In, and Ga, the DC life characteristics are significantly improved. It also has excellent life characteristics and nonlinear characteristics when AC is applied.

In the present invention, B i, 03.0o20. , , M
nO, Sb, 0. .

The reason why NiU is set to 0.1 to 5 mal1% each is because if it deviates from this range, the nonlinear characteristics and life characteristics will deteriorate.

AA', In, Ga is 0.0001 ma
Is it effective in the range of i1% to 0.05 mol? 11-8. Although A13+ and the like can be effective with a small amount of sprinkling, they exhibit excellent effects when m8710 is contained in an amount of 0,0001 mo1% or more of IC. Moreover, if there is too much, the characteristics will deteriorate. AI especially in non-linear characteristics
The effect of such attention is a dog. Since the effect of improving properties can be obtained with a very small amount, it is preferable to prepare an aqueous solution of a compound such as nitrate in water.

By adding B-treated glass to this basic composition, the timekeeping performance is improved, but the direct current life in particular is significantly reduced. That is, if only the basic composition is used, the V leakage 2t'4 current increases over time when DC voltage is applied, causing thermal runaway, and it is impossible to use B for DC applications.
By adding 0.001 to 1 wt% in terms of , the change in leakage current over time is reduced, and the direct molding life characteristics are dramatically improved.

If it is less than 0.001 wt%, the effect of adding the B-containing M glass will not be apparent, and if it is added in an amount of 0.001 wt% or more, the DC life characteristics in particular will be improved. If it exceeds 1 wt%, it will not only deteriorate the DC life characteristics, but also deteriorate the AC life and non-linear characteristics.

Even in the case where A11JFt is not present, the direct current life can be improved to some extent by adding B-containing glass, but this not only deteriorates the non-direct current characteristics but also leads to a significant decrease in discharge capacity.

When a voltage non-linear resistor is used for a device intended to absorb large surges, such as a power surge arrester, it is particularly required to have an excellent ability to handle energy per unit volume.

In order to express the energy processing capacity of a general VC voltage nonlinear resistor in a specific value, a 2 ms current rectangular wave is applied and a rectangular wave discharge capacity of υ per unit volume is used. (The test method is described in JffO-203P, 43, for example.) In other words, if the discharge withstand capacity is small, applying a large current impulse to a voltage nonlinear resistor will cause creeping flash or through-breakage. This will cause the surge to fail, failing to fulfill its original purpose of absorbing surges, and will also significantly reduce the performance of lightning arresters and other equipment.

In yarns that do not contain AI, In, or iJa, this discharge withstand capacity becomes small.

〔Effect of the invention〕

As explained above, according to the present invention, the DC life characteristic
It is possible to obtain a non-linear resistor with increased pressure. The resistor of the present invention also has excellent nonlinear characteristics and AC life characteristics.

Therefore, it is effective as a surge absorber for DC high-pressure feeding. Cross again? ) It is also effective for IC sending FJJ. It is good J1& for UHV in ql. Furthermore, since both DC and AC applications can be manufactured on the same line, there is also the advantage of low cost manufacturing. Since each characteristic VC is hidden, it is also effective as a consumer device.

[Embodiments of the invention]

Hereinafter, the present invention will be explained in detail.

B 1203 , 0o20s as a ZnOIC subcomponent
, MnU, 5b203゜NiU, Al(N
After preparing and mixing a glass containing US)s・9H20 and B in a desired composition ratio, PVA was added as a binder and granulated, and formed into a disk-shaped plate material.

After drying this temporary phase, it was fired for about 1,100 to 1,300°02 hours, and then polished on both sides.
A sintered body of m was formed. The glasses used are shown in Table 1.

Stain poles were formed on both surfaces of this sample by Al spraying, and an electric current non-1α ray resistor was formed on the surface of the sample, and various characteristics were measured.

The results are shown in Table 2. In Table 2, compositions outside the scope of the present invention are also shown as comparative examples. In Table 2, the voltage-current nonlinear characteristics are “J 2 K A
/ V ImA s life characteristic is indicated by L400. 'J
Bi was expressed as a weight ratio with respect to the basic components, with B2O5 added.

V (l m AI + f, 'voltage at 1 hour of flow) (0) I (400) is at an ambient temperature of 90°C, and in the case of D, O, a voltage of 0.75 x V'1 mA is applied for 400 hours. Leakage ton υIC measured at room temperature after continuing, A, O
In the case of , the leakage current was constant at 6111 at room temperature after a pressure of 0.85×V+mA was continuously applied for 400 hours. ■(0) is the initial value, L4o, o is I (400)
It is expressed as a ratio of 1 (0).

Note that the mark X in the table indicates that thermal runaway occurred within 400 hours. Also, in Table 2, one company shown in Table 1 was used as the glass type.

As is clear from Tables 1 and 2, in the examples of the present invention, D, O, I (400)/I (0) is small and the DC life is excellent. In addition, it can be seen that the other characteristics are AC life A, (j, I (400)/l (0), nonlinearity VIKA/■1 mA, and are originally 2-fold.

As is clear from the comparative examples (samples Nn 38', 39), if the amount of glass additive 7Jl is too small, the lifespan will be poor, and if it is too large, in addition to the life expectancy of υ, C0,
O, life and non-straightness also deteriorate.

As is clear from the ratio 1 bite example (sample Nn40.41), even if the glass contains an appropriate amount of Byc, if the amount of Al falls outside the range, the nonlinear characteristics will be greatly inferior, and the lvl.
If the amounts of C and Al are too large, thermal runaway will occur in both A, U, l) and the 0 mark. Furthermore, when i is small, the life characteristics are inferior, although it is not as noticeable when it is large.

Furthermore, if the amount of KA7 is outside the range, the discharge withstand capacity will be significantly degraded. Table 3 shows the discharge withstand capacity when changing the A/way for the composition system of sample floor 16. Similarly, Fig. 1 shows the radiation resistance characteristic diagram.

As is clear from Table 3 and Figure 1, within the reasonable range it is about 250 J/cya'', but outside this range it is extremely inferior to about 200 J/cya'' or less.

Effects similar to those shown in Table 3 A7 could also be obtained with In and Ga. The results are shown in Table 4. -The method is the same as above.〇As is clear from Table 4, In and Ga are the same as L, and by adding glass containing B, a varistor with excellent C life can be obtained. can be obtained.

When the crystal structure of Bi in the voltage-current nonlinear resistor according to the present invention was examined at 0°, it was found that an α phase (orthorhombic system) was formed. The ratio of this α phase in the total Bi2O3 changes depending on manufacturing conditions such as temperature and composition.

When we investigated the change in characteristics depending on the ratio of this α phase, we found that the total Si
20. It has been found that DC life characteristics are excellent when the α phase t (Rα) in i is 10% or more, preferably 30% or more, particularly 50% or more. This tendency is the same in the composition range of the present invention, A13+, In'',
Cta" and vh deviations were also the same. However, when the basic components were different, the α phase did not occur. For example,
Zn0-B 1203-Oo20. -MnO-N 1O
Even when B2O3 was added to the basic component of -sb2o3 plus 0r20= and Sin, no α phase was generated, and neither the nonlinearity nor the life characteristics were improved.

Further, this α phase changes into other phases by heat treatment. Therefore, it is desirable not to add a process that changes this crystal phase and includes a certain degree of heating.

Especially in the case of direct current application, B4O0 is improved with Rα210, and Bα? It settles down to an almost constant level at 50. If itα is small, thermal runaway will occur.

If no B-containing glass is added, α=0, and B
A pα phase begins to form upon addition of the containing glass.

Table 5 shows the relationship between the α phase-stitch and the properties in the above-mentioned samples.

The α phase was defined by Rα shown in the baby's weight.

Similarly to Table 5, 1 is also A due to changes in α, 01L400 (dashed line)
, D, 0L400 (solid line) is shown in Figure 42. As is clear from the figure, ltα grows in the region where lO is not grooved, and O.

[Mark 7Jl] Sometimes thermal runaway occurs. A, O, 'L400 becomes stable when Rα〉3O, and l is also a 2.50
As the temperature increases, O and B4O0 become stable.

[Brief explanation of the drawing]

Figures 1 and 2 are characteristic curve diagrams. Agent: Patent attorney Noriyuki Kon (1 person) Figure 1 Figure 2

Claims (1)

[Claims] Zinc oxide is the main component, and bismuth is a subcomponent. Cobalt, manganese, antimony, and nickel are IJ 1203, 0o20B, MnU, Sb, respectively.
03, converted to NiO, Hi2030.1~5mo7%, 0o20s 0.1~
5mo1%. Mn0 0.1-5mol%, 5b2030.1-5r
no1%. Ni0 0.1 to 5 mo1% Furthermore, boron is 820. Convert to 0.001～
A voltage/current nonlinear resistor comprising a sintered body in which glass containing boron is added in an amount of 1 wt%.