JPS61128427A - Fluidic operator for switchgear - 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 The present invention relates to an operating device for a power circuit breaker, and more particularly to a fluid operating device for a circuit breaker with improved contactor closing and breaker cylinder fluid control valves.

[Conventional technology]

SF6 gas, which has excellent insulation performance and current cutoff performance, is used as an arc extinguishing medium, and during the cutoff process, the movable contactor is operated as a piston to sufficiently compress the SF6 gas sealed in the buffer chamber, resulting in high-pressure gas. Many so-called buffer-type gas circuit breakers are in practical use, which extinguish the arc by spraying it onto the arc.

In particular, hydraulic operation is mainly used as the operating mechanism for buffer-type circuit breakers in 800W and 500W systems, and because it provides a large operating force, it is also possible to perform high-speed interrupting of two cycles or more. , the interrupting performance is improved.

In the case of the hydraulic operation method, the fluid pressure is greater than that of the compressed air operation method, and the operation mechanism can be made compact and economical. However, as the speed of the circuit breaker increases, the hydraulic operating mechanism and, for example, the electromagnetic switching valve that controls it, must also become larger. Generally, electromagnetic repulsion type control valves are used, but in order to obtain a large force, they need to be made larger.

[Problem that the invention seeks to solve]

On the other hand, in order to solve the problems associated with higher speed circuit breakers and meet the demand for improved breaking performance, we selected the optimal breaking speed according to the voltage and current conditions of the line at the time of breaking, and developed ultra-high-speed circuit breakers. Reducing the large stress placed on the circuit breaker drive section helps improve circuit breaker reliability. Furthermore, by selecting the breaking speed in consideration of parameters that determine the breaking duty, such as the current to be interrupted, and by changing the speed pattern during breaking, the range of breaking conditions that can be covered by the circuit breaker expands. As a result, china clay with blocking performance is revealed.

Furthermore, as is clear from the travel curve (stroke time curve) of the circuit breaker shown in Fig. 8, when the aforementioned buffer type circuit breaker does not perform speed control during operation (
The travel curve (shown by the dotted line) is distorted, which has an undesirable effect on the shutoff characteristics, but being able to control the speed during shutoff provides an effective means of solving this problem. From these viewpoints, it has been desired to develop a means for controlling the speed of the circuit breaker using ON-LINE.

[Means for solving problems]

The present invention was made to meet these demands.
The purpose of this is to apply a linear motor which has a larger output than an electromagnetic repulsion type control valve or the like, and which has an extremely fast response of 2 to Bms during drive.

[Effect]

In addition to using a linear motor, a linear motor drive signal current editing and conversion device is installed to know the voltage and current status of the line at the time of interruption on 0N-LINE and to perform optimal speed control of the circuit breaker according to the situation. By controlling the drive of the motor and driving the main fluid control valve with a linear motor without using a width increasing valve, so-called ON-LINE speed control that can perform optimal speed control of the circuit breaker becomes possible.

[Embodiments of the invention]

The present invention will be explained according to an embodiment shown in FIG.

(1) is a cut-off contact, (2) is a hydraulic cylinder that closes or cuts off this contact (1), and (3) is a main control valve, and this main control valve (3) is controlled by a near motor (4). .

The linear motor (4) has a permanent magnet (5) and a coil (6)
A permanent magnet (5) is installed movably in the longitudinal direction of the coil (6). A main control valve (3) is formed at one end of the permanent magnet (5) together with a valve box (8) configured to surround the spool (7).

The valve box (8) has a hole (b) with a pipe line (9) that opens at the constricted part in the middle of the spool (7), and a pressure oil side that communicates with the pipe line (9) through a spool land. Pipe α
The hole (to) where Q was installed and the oil drain side pipe αυ, which also communicates with the pipe (9) through the spool land, are installed at 6α.
There is a shoulder. Note that the holes αs and uq are both oil drains. The hydraulic cylinder (2) consists of an auxiliary cylinder, a piston (G), and a rod (4).A pipe line (9) supplies pressure oil for injection from the piston head side and pressure oil for shutoff from the rod side, and cA is the cylinder αη. are installed respectively. (28a), (2ab), (28c)
Both are low-pressure tanks that store return oil. (Incorporated) is an accumulator that constantly stores pressure oil, and the pressure oil is constantly replenished by a pump (not shown). Zeng and Zeng are a current transformer (CT) and a transformer (FD) for respectively detecting the voltage and current state of the line to be cut off, and this information is sent to the sequential speed control pattern determining device diagram. Furthermore, it is sent as speed control pattern information to the linear motor drive signal signal converter q. The signal conversion device q receives a command to operate the circuit breaker and converts the fixed side coil (6) of the linear motor (4) based on the instantaneous speed control pattern of the shutdown command stored in the speed control pattern determination device described above. The permanent magnet (5) of the linear motor (4) repeatedly moves and stops at a predetermined position at high speed by excitation and demagnetization of the coil (6) by the signal current. .

First, when trying to close the circuit breaker contact (1) as shown in the figure, the closing operation command given to the circuit breaker is converted into a series of drive signal currents via the converter peak and is output to the linear motor (4
). The linear motor repeats a series of drive stops according to a set pattern based on the state of the line to be cut off, and the main control valve (3) is switched to the position shown.

Now, high pressure oil is supplied to the rod side of the piston through the pipe (E) during both the turning on and shutting off, but by switching the main control valve (3) mentioned above, is a hole (
2) Since the high pressure oil is also supplied to the head side of the piston, the piston moves to the left and the contact (1) of the circuit breaker is closed.

When a shutoff operation command is given, a series of drive signal currents are transmitted from the converter end to the linear motor and the main control valve (3)
switch to the opposite position.

As a result, the pipes (9) and (6) are communicated through the holes □□□ and ae, and the pressure oil on the cylinder head side is discharged, and the pressure difference between the rod side and the head side causes the circuit breaker contact (1 ) is blocked.

Next, speed control will be explained using FIG. 2. (
a) = (b) → (c) - (d) is the process from the closed state to the closed state, and (d) → (e) → (f) → (a
) is the main control valve (3) in the process from shutoff state to closed state
The position of the spool (7) inside is shown.

The positions of each of these spools are indicated by (a) to (f) shown in the solid line travel curve (stroke one hour curve) in Figure 8.
) corresponds to the symbol.

Spool (7) stopped on the left in the loaded state in (a)
moves to the right in response to a breaking operation command, and moves to position (b) when the load on the buffer cylinder of the circuit breaker is large and it is necessary to maximize the breaking speed. As the load on the buffer cylinder decreases, less force is required to maintain the same speed, so the spool (7)
is moved further to the right to reduce the cross-sectional area of the big end, increasing the exhaust pressure on the cylinder head side and controlling the speed.

At the end of the shutdown, as shown in (C), the spool (7) is further moved to the right and the large end is squeezed close to the fully closed state to increase the braking effect by meter-out control and achieve a stop with a small impact force. I can make you do it.

When stopping in the cut-off state after the cut-off is completed, the spool (7) is pulled back to the left as shown in (d) to maintain complete communication between the hole @ and the α slope.

When charging, the spool (7) is moved to the left as shown in (e) to communicate the hole (to) and (2). By doing so, the hydraulic cylinder (2) forms a differential circuit.

The speed is controlled by moving the spool (7) to the left in the same way as when shutting off.

At the end of the charging process, as shown in (f), the spool (7) is further moved to the left and the hole (2) is squeezed to a nearly fully closed state to increase the braking effect through meter-in control and achieve a stop with a small impact force. can be made to do so.

In such a configuration, an amplification valve and a dashpot for braking, which are necessary when using an electromagnetic repulsion type control valve, are unnecessary, and the structure is simple, resulting in a small operating mechanism.

FIG. 4 shows a part of the structure of another embodiment of the present invention using a rotary main control valve. In the figure, the Foundation is a rotary main control valve with a rotary valve body (2
) and a valve box (e) that rotatably surrounds it.

One end of the lever is fixed to a rotating valve body.
The other end of the beam is rotatably connected to the permanent magnet (5) of the near motor via a pin.

The valve box (7) has holes (12a), (18a), (14
a) is provided, and its functions are the hole (b) provided in the valve box (8) of the linear main control valve mentioned above, a3. (B)
correspond to each.

As is clear from the figure, when an operation command is given and the linear motor (4) performs a linear motion, the rotary main control valve rotates and connects the communication hole (2a) with the hole (1aa) or (14a).
The speed is controlled by narrowing the flow path between the two.

Furthermore, in the above embodiments, the case of a buffer-type circuit breaker was explained, but in the case of disconnectors and grounding devices that require current switching performance, there are many that are equipped with a buffer cylinder, and this is a standard for such equipment. Application of the invention produces effects similar to those of the embodiments described above.

〔Effect of the invention〕

As described above, according to the present invention, a linear motor is used as the drive device for the main control valve of the fluid operating mechanism, and the voltage and current state of the line at the time of interruption is detected by 0N-LINE, and the In order to perform optimal speed control of the circuit breaker, a signal conversion device for the drive signal current of the linear motor is provided to control the drive of the linear motor, and the main fluid control valve is driven by the linear motor without using a width increaser valve. Since the fluid operating device is configured to perform optimal speed control of the circuit breaker, unnecessary mechanical stress applied to the circuit breaker is reduced, and as a result, operational reliability of the circuit breaker is improved.

At the same time, there is an advantage that the range of breaking conditions that can be covered by the circuit breaker is expanded.

[Brief explanation of the drawing]

Fig. 1 is a structural diagram of a fluid operation mechanism of a circuit breaker according to an embodiment of the present invention, Fig. 2 is an explanatory diagram of the operation of the main control valve, Fig. 8 is an explanatory diagram of the travel curve of the circuit breaker, and Fig. 4 is a diagram illustrating the travel curve of the circuit breaker. FIG. 7 is a structural diagram showing a main part of a fluid operation mechanism of a circuit breaker showing another embodiment of the present invention. Figure smell. (1) is a contact, (2) is a hydraulic cylinder, (3) is a main control valve (fluid control valve), (4) is a beam near motor, ... is a signal conversion device, and (Foundation) is a speed control pattern determination device. be. Note that the same reference numerals in each figure indicate the same or corresponding parts.

Claims (1)

[Claims] A cylinder driven by a contact and a fluid control valve that controls the supply of fluid to the cylinder for closing and shutting off the contact, wherein the circuit breaker a first device that generates information regarding a speed control pattern of the linear motor; and a second device that converts the speed control pattern into an electrical signal for driving a linear motor according to commands for turning on and off.
A linear motor drive signal outputted from the device is transmitted to the linear motor, and the cylinder is selectively driven in different directions by operating a fluid control valve using the displacement of the linear motor to switch the fluid passage. , the fluid control valve driven by the linear motor is given a throttling effect by setting a position in the middle of switching of the fluid control valve to a position different from a final stop position in the shutoff or closing state. A fluid operating device for a switchgear, characterized in that the speed of the cylinder is controlled.