JPH0628703Y2 - Shunt reactor load current measuring device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial field of application) The present invention relates to a load current measuring device for a shunt reactor.

(Prior Art) A shunt reactor in which a main coil and an auxiliary coil are provided and an auxiliary switch connected to the auxiliary coil is turned on / off to switch the capacity is already proposed separately. See Japanese Laid-Open Publication No. 61-105823, Japanese Patent Publication No. 5
-86641)].

FIG. 2 shows the structure of an example thereof, and 1 is a main reactor portion, which is composed of iron core legs 2 to 4 and main coils 5 to 7 wound around the iron core legs 2 to 4. Reference numeral 8 is an upper yoke core, and 9 is a main switchgear connected to the main coils 5 to 7. The neutral point side of the main coil 5 is connected together.

Reference numeral 12 denotes an auxiliary reactor portion, which includes core legs 13 to 15 and auxiliary coils 16 to 18 wound around the core legs 13 to 15.
It is composed of and. 19 is a lower yoke iron core, 2
Reference numeral 0 is an auxiliary switchgear connected to the auxiliary coils 16-18. Both reactor parts 1 and 12 have an intermediate yoke core 2
It is integrally configured via 3.

In the configuration shown, the main coils 5 to 7 and the auxiliary coils 16 to 18 are connected in parallel, and the auxiliary switching device 20 is connected to the neutral point side of the auxiliary coils. The shunt reactor is connected to the system line via the main switchgear 9.

Here, if the main switchgear 9 is turned off, the capacity connected to the system is zero, and if the main switchgear 9 is turned on and the auxiliary switchgear 20 is turned off, the capacity determined by the main coils 5 to 7 is reduced. When both switchgear are turned on, the capacity determined by both the main and auxiliary coils will be connected to the system.

By the way, in such a shunt reactor, it may be required to individually measure the load currents flowing in both the main coil and the auxiliary coil. For example, when it is desired to detect the temperature of each coil, this cannot be directly performed, and therefore the thermometer may be operated from each load current.

A current transformer may be used to measure the load current. FIG. 3 shows a connection diagram at that time. This figure shows one phase of the shunt reactor of FIG. 2, 21 is a switching element for one phase of the auxiliary switch 20,
Reference numeral 32 is a current transformer inserted in each circuit of the main coil 5 and the auxiliary coil 16.

By the way, in this kind of shunt reactor, it is usual that each iron core around which a coil is wound is housed in an oil-filled tank 33 for use. On the other hand, since the current transformers 31 and 32 separately measure the currents flowing through the main coil 5 and the auxiliary coil 16 as described above, the branch point A of both coils 5 and 16 and each coil 5 are measured as shown in FIG. It is necessary to insert the current transformers 31 and 32 between the current transformers 16 and 16.

In this case, if the branch point A is provided in the tank 33, each of the current transformers 31 and 32 must be independently installed inside the tank 33 rather than the branch point A. However, as a current transformer that must be independently installed deep inside the tank 33 in this manner, a current transformer having a complicated structure must be used.

(Problems to be solved by the invention) This invention is composed of a main reactor part connected to a system line via a main switchgear and an auxiliary reactor part connected in parallel to the main reactor part via an auxiliary switchgear. In a road reactor, when measuring the load current flowing in each reactor part by a current transformer, it aims at simplifying the structure of the current transformer for the measurement.

(Means for Solving Problems) The present invention is directed to a first tube transformer for measuring a load current flowing through a main switchgear and a second tube for measuring a load current flowing through an auxiliary switchgear. A current transformer is provided so that the load current flowing in the auxiliary reactor portion is the secondary current of the second sleeve current transformer, and the load current flowing in the main reactor portion is the difference between the secondary currents of both sleeve current transformers. It is characterized in that it is detected by.

(Embodiment) An embodiment of the present invention will be described with reference to FIG. 1 corresponding to FIG. The same reference numerals as in FIG. 3 indicate the same or corresponding parts. According to this invention, a line 41 connecting the branch point A between the coils 5 and 16 and the main switchgear 9 is connected.
The first sleeve current transformer 42 is inserted into. Further, the second sleeve current transformer 44 is inserted into the line 43 connecting the switching element 21 for one phase of the auxiliary switching device and the auxiliary coil 16. Each trocar current transformer 42, 44 can be easily installed by using a trocar used when the lines 41, 43 are passed through the tank 33. That is, 10 is the tank 33.
The tube 41 is installed on the wall surface of the tube so as to pass through it, and the line 41 is inserted into the tube and led out to the outside. The lower portion 10A of the sleeve 10 is inside the tank 33, and the sleeve current transformer 42 is configured by disposing a current transformer coil so as to surround the lower portion 10A. Similarly, reference numeral 11 denotes a sleeve tube which is installed on the wall surface of the tank 33 so as to penetrate therethrough, and the line 43 is inserted into this sleeve and led out to the outside. The lower portion 11A of the sleeve 11 is inside the tank 33, and the lower portion 1A
The trocar current transformer 43 is configured by arranging a current transformer coil in 1A so as to surround it.

Since the trocar current transformer can be constructed by the trocars used for passing the respective lines 41 and 43 in this way, like the current transformer to be independently installed inside the tank 33 as shown in FIG. There is no need to use current transformers of complicated structure.

Reference numerals 45 and 46 are dial type temperature indicators operated by currents flowing in the respective coils, and 47 and 48 are display portions thereof.
49 and 50 are heat coils, and 51 and 52 are sensing units. Then, the secondary current of the tube current transformer 44 is made to flow through the heat coil 50, and the current of the difference between the secondary currents of the tube current transformers 42 and 44 is made to flow through the heat coil 49. I am doing it.

In the above configuration, when both the switchgear 9 and 20 are turned on, if the current flowing through the main coil 5 is I ₁ and the current flowing through the auxiliary coil 16 is I ₂ , the current flowing through the main switchgear 9 is I. It becomes ₁ + I ₂ . Now, assuming that the secondary currents of the trocar current transformers when the currents I ₁ and I ₂ respectively flow in the trocar current transformers are i ₁ and i ₂ , respectively, the secondary current of the trocar current transformer 42 is The current is i ₁ + i ₂ , and the secondary current of the tube current transformer 44 is i
It becomes ₂ .

Therefore, the current of the difference between the secondary currents of the two tube current transformers, that is, the current i ₁ flows through the heat coil 49, and the secondary current of the tube current transformer 44 flows through the heat coil 50. Therefore, each temperature indicator 45, 46 is connected to each coil 5,
The temperature of each coil corresponding to the load currents I ₁ and I ₂ flowing in 16 is indicated.

Although FIG. 1 shows one phase of the shunt reactor, it goes without saying that each phase is similarly connected.

(Effect of the Invention) As described in detail above, according to the present invention, since the load current flowing in each coil can be measured from the current flowing in the main and auxiliary switchgear, a current transformer for the measurement can be used.
Since it can be inserted in a line connecting the main and auxiliary coils and the main and auxiliary switchgear, a trocar current transformer using a trocar used as the current transformer to draw the line to the outside Can be used, and has the effect of simplifying the configuration of the current transformer as compared with the conventional current transformer installed independently inside the tank.

[Brief description of drawings]

FIG. 1 is a connection diagram showing an embodiment of the present invention, FIG. 2 is a connection diagram of a variable capacity type shunt reactor, and FIG. 3 is a commonly considered connection diagram. 1 ... Main reactor part, 5-6 ... Main coil, 9 ... Main switchgear, 12 ... Auxiliary reactor part, 16-18 ...
Auxiliary coil, 20 ... Auxiliary switchgear, 41,43 ... Line, 42,44 ... Trouble transformer,

Claims (1)

[Scope of utility model registration request] 1. A system line is connected through a main switchgear,
A shunt reactor is configured by a main reactor part in which the neutral point side is collectively connected and an auxiliary reactor part in which the neutral point side is collectively connected via an auxiliary switchgear and is connected in parallel to the main reactor part. And a first sleeve transformer for measuring a load current flowing through the main switchgear,
Second for measuring a load current flowing through the auxiliary switchgear
And a load current flowing in the auxiliary reactor portion by a secondary current of the second charge converter current transformer, and a load current flowing in the main reactor portion by a load current flowing in the two reactor tubes. A load current measuring device for a shunt reactor, which is detected by the difference in the secondary current of each device.