JPS5923089B2 - Tap changer drive control device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an improvement in a drive control device for a tap changer.

In order to issue a stop command at a predetermined tap position, a conventional drive control device uses a rotary switch and the same number of electromagnetic contactors as the number of taps, as shown in FIG.

In Figure 3, 24M is a three-phase induction motor that drives the tap changer, and 24R is the two main contacts 24Rm and auxiliary contact 2.
Magnetic contactor for upward switching having 4Ra and 24Rb, 24
L is two main contacts 24Lm and auxiliary contacts 24La, 24L
The electromagnetic contactor 24P for downward switching having b is driven from 24M via a reduction gear and is a rotary switch consisting of a current collecting ring, a movable contact, a fixed contact with several tap points, and a baking plate. As shown in Figure 4 (a), it is possible to
Perform two notch operations. 1x to 5x are electromagnetic relays sequentially energized by 24P, each having two auxiliary contacts 1xb to 5xb.

The PS closes at the middle position of each tap as shown in Figure 4,
It is a cam switch that opens when tapped in place. 43P is an operating rotary switch for instructing a predetermined tap.

In the above description, a means a normally open contact and b means a normally closed contact. This conventional device uses a rotary switch and requires the same number of electromagnetic relays as the number of tap points, so it has the following disadvantages. (1) The mechanism is complicated.

(2) The contacts of the rotary switch are prone to wear, and there is a risk of dielectric breakdown due to abrasion particles.

(3) The life of the device is short.

(4) Cost is high.

The present invention was made to solve the above problems, and its purpose is to replace the rotary switch rotated by an electric motor used in the conventional drive control device with a cam switch. It is an object of the present invention to provide a drive control device for a tap changer that is highly reliable, inexpensive, and has a simple mechanism.

The details of the present invention will be explained below with reference to the drawings.

FIG. 1 is a circuit diagram showing an embodiment of the tap changer drive control device according to the present invention, and FIG. 2 is an explanatory diagram of the operation sequence of each cam switch. In Fig. 1, 1 is a three-phase induction motor connected to a power supply, 2 is a reducer, and 3 is driven by the electric motor 1 via the reducer 2, and rotates in both forward and reverse directions to switch the tap position. The tap changer 4 consists of a first cam 4-0 that rotates together with the tap changer 3, and microswitches 4-1 to 4-5 (only one is shown in the figure) of the same number as the number of tap positions. 5 is a second cam switch consisting of a second cam 5-0 that rotates together with the tap changer 3, and a micro switch 5-1; 6 is a terminal of the motor 1 connected to the power supply; 7 is a pair of cam switches. An electromagnetic contactor for upward switching has a main contact 7a and auxiliary contacts 7b, 7c, 8 is an electromagnetic contactor for downward switching having a pair of main contacts 8a and auxiliary contacts 8b, 8c, 9 is the number of tap positions of the tap changer The tap position selection switch has one fixed contact, one current collecting contact, and one movable contact, which are arranged in the same number and in the same order as the tap positions of the tap changer. Note that each of the contacts 4-1a to 4 of the plurality of micro switches 4-1 to 4-5 in the first cam switch 4
-5a is connected in series in the same order as the contact point of the tap position selection switch 9, and as shown in FIG. When the tap position selection switch is within the desired range, the corresponding contact of the tap position selection switch is opened, and when it is outside the desired range, it is closed.

Also, the micro switch 5 in the second cam switch 5
-1 contact 5-1a is immediately after, the other one is the electromagnetic contactor 7
. When it is outside the desired range, it is open, and when it is outside the desired range, it is closed. In this tap changer drive control device,
During the upward switching operation, for example, when the tap position of the tap position selection switch 9 is changed from 1 to 2, the contact 4-1a of the first cam switch 4 is open, and the other four contacts 4 are open.
-2a to 4-5a are closed, so the tap position selection switch 9 and the first cam switch are closed.
-2a to 4-5a, the upward switching electromagnetic contactor 7 is energized via the auxiliary contact 8b of the downward switching electromagnetic contactor 8,
Electric motor 1 starts to start.

After a while, the contact 5-1a of the second cam switch 5
is closed, then the contact 4-2a of the first cam switch 4 is opened, and the contact 4-1a is closed. In this case, current is passed through the electromagnetic contactor 7 for upward switching via the contact 5-1a of the second cam switch 5, the auxiliary contact 7c of the electromagnetic contactor 7 for upward switching, and the auxiliary contact 8b of the electromagnetic contactor 8 for downward switching. It will be.
That is, the upward switching electromagnetic contactor 7 is self-held by its auxiliary contact 7c. When the electric motor 1 further rotates, the contact 5-1a of the second cam switch 5 opens, the electromagnetic contactor 7 for upward switching is deenergized, and the current flow to the electric motor 1 is switched to the main contact of the electromagnetic contactor 7 for upward switching. 7a opens, the tap changer 3 stops at the position where the tap position is changed from 1 to 2, and the tap change is completed. Further, during a downward switching operation, for example, when changing the tap position of the tap position selection switch 9 from 2 to 1, the contact 4-2a of the first cam switch 4 is open and the other The four contacts 4-1a and 4-3a
4-5a are closed, the downward switching electromagnetic contactor 8 is energized via the operation panel 9, the contact 4-1a of the first cam switch 4, and the auxiliary contact 7b of the upward switching electromagnetic contactor 7. The electric motor 1 starts to start.

After a while, first the contact 5-1 of the second cam switch 5
a closes, then the contact 4-1a of the first cam switch 4 opens and the contact 4-2a closes, and the downward switching electromagnetic contactor 8
is energized via the contact 51a of the second cam switch 5, the auxiliary contact 8c of the downward switching electromagnetic contactor 8, and the auxiliary contact 7b of the upward switching electromagnetic contactor 7. That is, it is self-held by the auxiliary contact 8c of the downward switching electromagnetic contactor 8. When the electric motor 1 further rotates, the contact 5-1a of the second cam switch 5 opens, the downward switching electromagnetic contactor 8 is deenergized, and the flow of current to the electric motor 1 is reduced until the main contact 8a of the downward switching electromagnetic contactor 8 is opened. When the tap is released, the tap changer 3 stops at the position where the tap is changed from tap position 2 to tap position 1, and the tap change is completed. As mentioned above, in the present invention, a cam switch is used instead of a rotary switch rotated by an electric motor to change the taps, so the electromagnetic relay in the conventional device using the rotary switch is not required. According to the present invention, it is possible to provide a drive control device for a tap changer with a simple mechanism, high reliability, low cost, and long life.

Note that the configuration of the present invention is not limited to the above-mentioned embodiments, and for example, a proximity switch or the like may be used instead of a micro switch in each cam switch.

[Brief explanation of the drawing]

Fig. 1 is a circuit diagram showing an embodiment of the tap changer drive control device according to the present invention, Fig. 2 is an explanatory diagram of the operation sequence of each cam switch, and Fig. 3 is a circuit diagram showing a conventional example of the tap changer drive control device. The circuit diagram of FIG. 4A is an operational diagram of the conventional rotary switch 24P and cam switch PS. 1...Electric motor, 2...Reducer, 3...
...Tap changer, 4...First cam switch, 5...Second cam switch.

Claims (1)

[Claims] 1. A first cam switch and a second cam switch described in a) and b) below are provided, and the first tap on the switching command side is switched from the first tap during operation to the first tap on the switching command side. In switching to the adjacent second tap, the electromagnetic contactor, the electric motor, the first cam switch, the second cam switch, and the tap changer are configured to operate in the order c) below, and the tap position selection switch A tap changer drive control device characterized in that, when the commanded tap is different from the second tap, the operation c) below is continuously repeated until the commanded tap is reached so that a desired tap can be selected. a) a first cam that rotates in correspondence with the tap changer;
The switch is opened and closed by the first cam, and is composed of the same number of switches as the number of tap positions of the tap changer, and each contact of the switch is connected in series in the same order as the tap position, and each contact of the switch corresponds to the number of tap positions. A first cam switch configured to open when the switch is within a desired range including the home position and close when the switch is outside the desired range. b) It consists of a second cam that rotates in correspondence with the tap changer, and one switch that is opened and closed by the second cam, and the contacts of the switch are configured to control each tap position, including each tap position, as desired. A second cam switch configured to open when within the range and close when outside the desired range. c) The electromagnetic contactor on the switching command side is energized by the switching command from the tap position selection switch, and the electric motor that rotates the tap changer, the first cam, and the second cam rotates, and the second cam is rotated first. This closes the contact of the second cam switch, maintains the rotation of the motor, and the tap changer continues to rotate. on the other hand,
The first cam switch is such that after the contacts of the second cam switch are closed, the contacts of the first cam switch corresponding to the second tap are opened, and then the contacts of the first cam switch corresponding to the first tap are closed. The cam switch contacts close. As the motor further rotates, the second cam switch contact opens and the tap changer reaches a predetermined position, completing the changeover from the first tap to the second tap.