JP4627417B2 - Power circuit breaker - Google Patents

Description

  The present invention relates to a power circuit breaker, and more particularly to a power circuit breaker suitable for high voltage specifications such as a substation and a switching station.

  Power circuit breakers provided in substations and switch stations maintain a current-carrying state during normal operation, and cut off the current when an abnormal current is generated in the power system due to a lightning strike or the like. As the operating device for driving the circuit breaker, since the demand for electric power is increasing, a hydraulic type or a spring type is frequently used from the viewpoint of high speed and small size and light weight of the circuit breaker.

  The operating device operates an electromagnet, which is a type of electromagnetic actuator, when a shutoff or closing command is input regardless of the drive system. Then, the holding of the driving force for blocking or closing is released. An example using such an electromagnet is described in Patent Document 1. In the operation device described in this publication, the cutoff spring force in the energized state is held using the cutoff latch, the second cutoff latch, and the cutoff trigger of the cutoff control mechanism, and the cutoff spring force during the cutoff operation is detected by the electromagnet plunger. Press to release. Further, the closing spring force is held or released by using a closing latch, a closing trigger, and a closing electromagnet of the closing control mechanism.

  Patent Document 2 describes another example of a conventional power circuit breaker. In the circuit breaker described in this publication, a two-stage mechanism including a latch and a trigger is used to perform a blocking operation, and a control switch and a delay capacitor are provided in the blocking control circuit. Thereby, the excitation of the breaking electromagnet is delayed, the opening time is delayed, the direct current component is reduced, and the short-circuit current is cut off.

JP 2003-115243 A (page 5, FIG. 1)

JP-A-4-368745 (Page 4, FIG. 1)

  The breaker open / close pole time is mostly the operation time of the plunger and the operation time of the mechanism from the break trigger or closing trigger to the movable iron core. The operation time of the latter mechanism is generally determined from the driving force and the inertial mass of the interruption and closing. The operation time of the former plunger is determined by the attractive force and load generated by the electromagnet. However, when converting the electrical energy supplied to the electromagnet to magnetic energy, loss of strong non-linearities such as magnetic flux leakage and eddy current loss occurs in the iron core, and it is difficult to accurately predict this loss. is there.

  In the conventional operating device, when the breaking capacity of the breaker increases, the driving force necessary for breaking the current increases, so that the force acting on the trip trigger of the breaking control mechanism increases. As a result, the load on the breaking-side electromagnet also increases, so that the magnetic circuit is improved by increasing the size of the electromagnet. However, the magnetic resistance increases and the operation of the plunger becomes slow.

  Therefore, if the plunger operating time is slower than the target opening time, the material of the iron core is changed to a material with excellent magnetic properties such as 3% silicon steel, and the rise of the attractive force is improved by accelerating the magnetization of the iron core. ing. According to this method, it is possible to cope with a breaker having a large breaking capacity, but the types of electromagnets of the operating device increase according to the breaking capacity.

  In the case where individual differences occur due to part manufacturing errors or assembly errors, it is necessary to adjust the opening / closing pole time at the time of product shipment. For this purpose, the operating device described in Patent Document 1 adjusts the engagement margin between the trigger and the latch and the idle travel distance of the electromagnet plunger. In the method of adjusting the idling distance, if the engagement allowance is small, the opening time may be too fast or unstable operation may be caused. In the circuit breaker operating device described in Patent Document 2, the electrical circuit delays the opening time without adjusting the engagement margin between the trigger and the latch. However, it is not considered that the load of the electromagnet changes according to the breaking capacity.

  The present invention has been made in view of the above problems of the prior art, and an object thereof is to share an electromagnet in a power circuit breaker having a large and small current breaking capacity. Another object of the present invention is to make the attractive force of the electromagnet variable without changing the engagement margin between the trigger and the latch of the power circuit breaker.

  A feature of the present invention that achieves the above object is that, in a power circuit breaker that uses a force generated by an electromagnet for a switching operation of a contact having a stationary contact and a movable contact via a cam and a link mechanism, the electromagnet is linearly operated. A movable plunger, a movable iron core attached to the plunger, and metal first and second fixed iron cores adjacent to the movable iron core, the magnetic properties and resistivity of the first fixed iron core being It is different from those of the second fixed iron core.

  In this feature, two movable iron cores may be arranged in the axial direction, and an annular recess for accommodating a coil is formed in the first fixed iron core, and the first fixed iron core and the second fixed iron core are formed. May be arranged adjacent to each other in the axial direction. Further, the first fixed iron core is formed in a cylindrical shape and arranged on the inner peripheral side of the second iron core, and a plate that engages with the side surfaces of the first and second fixed iron cores is provided. The first fixed core may be detachable from the electromagnet by releasing the engagement of the second plate.

  In the above feature, the movable iron core and the first fixed iron core may each have a conical surface formed adjacent to each other, and the cones may have substantially the same inclination. At least one of the two fixed iron cores may be made of materials having different magnetic characteristics. Further, the first fixed iron core and the second fixed iron core are connected by an inlay shape, and the axial length of the inlay portion is made longer than the second fixed iron core by the first fixed iron core, so that the volume of the recess is increased. Alternatively, an annular coil may be arranged between the first fixed core and the second fixed core, a capacitor may be connected in series to the coil, and a resistor may be connected in parallel to the capacitor.

  Another feature of the present invention that achieves the above-mentioned objects is a shut-off unit that opens and closes a contact having a fixed contact and a movable contact to switch power off and on, a shut-off member that opens and closes the contact, and a throw-in member, A power control system comprising a shutoff control mechanism and a throwing control mechanism for holding or releasing the driving force by the shutoff member and the throwing member, and an electromagnet having a built-in coil excited by a shutoff command or a throwing command and having a fixed iron core and a movable iron core In the circuit breaker, the fixed core of the electromagnet has at least first and second divided shape portions, and the first divided shape portion and the second divided shape portion are made of metal materials having different magnetic properties and specific resistance. It is what has been.

  In this feature, the divided shape of the movable iron core may be divided in a direction perpendicular to the operation direction, or may be divided in a direction parallel to the operation direction.

  According to the present invention, since the fixed iron core or the movable iron core is divided and the iron cores are combined with different materials, the attractive force generated by the electromagnet can be changed. As a result, the electromagnet can be shared regardless of the current interruption capacity. Further, since the operation time of the plunger can be adjusted without changing the engagement margin between the trigger and the latch in the control mechanism, the reliability of the power circuit breaker is improved and the adjustment of the open / close pole time is facilitated.

  Hereinafter, some embodiments of a power circuit breaker 100 according to the present invention will be described with reference to the drawings. FIGS. 1-8 is a figure of one Example of this invention, FIG. 1 is a longitudinal cross-sectional view of the electromagnets 201 and 202 part which the circuit breaker 100 for electric power has, FIG.2 and FIG.3 is a figure explaining the characteristic, 4 is a front view of the power circuit breaker 100, and FIGS. 5 to 8 are schematic views of an operation mechanism of the power circuit breaker 100. FIG.

  As shown in FIG. 4, the power circuit breaker 100 includes a horizontally disposed cylindrical tank 103 and two left and right bushings 101 and 102 extending obliquely upward from the cylindrical tank 103. A box 104 for storing the operation device is provided on the side of the cylindrical tank 103. The cylindrical tank 103 is placed on a gantry 105, and the gantry 105 and the box 104 are connected to each other.

For example, SF ₆ gas (sulfur hexafluoride gas) is enclosed in the cylindrical tank 103 at a specified pressure. Further, a contact provided with a movable contact and a fixed contact (not shown) is also accommodated. In the bushings 101 and 102, conductors that connect the electric wires in the substation and the switching station to form an electric circuit are accommodated.

  In the power circuit breaker 100 configured as described above, power is supplied to the conductor in the cylindrical tank 103 via the bushing 102 on the upstream side from the system during normal energization. The contact formed at the tip of the conductor is closed, and power is supplied to the bushing 101 on the downstream side from the conductor connected to one of the contacts, and the power is returned to the system again. When an accident occurs in the system due to a lightning strike or the like, the operating device in the box 104 is driven to open a contact, and the supply of power to the downstream side is interrupted.

  Operation | movement of the operating device which the circuit breaker 100 for electric power has is demonstrated using FIGS. The power breaker 100 is in the on state. The power circuit breaker 100 includes a shutoff control mechanism 401 having an electromagnet 201, a closing control mechanism 402 having an electromagnet 202, a shutoff spring portion 403 centered on the main shaft 4, a closing spring portion 404 centered on the camshaft 2, and It has a contact portion 405 for turning on or off power. The spring force of the cutoff spring 26 provided in the cutoff spring portion is released to cut off the electric power, and the spring force of the closing spring 28 is released to turn on the electric power. The shut-off spring 26 is stored by the release of the closing spring 28, and the closing spring 28 is stored by the drive motor 50 and the reduction gears 51 and 52.

  The contact portion has one end attached to the main shaft 4 and the other end forming a movable contact 32, a fixed contact 29b with which the movable end of the movable contact 32 contacts, and the rotation of the movable contact 32. And a fixed contact 29a that forms a moving end portion. The cutoff spring portion has a main lever 5 attached to the main shaft 4 and having a T shape. A roller 6 is attached to one end of the main lever 5, and a roller 7 is attached to one end. A rod-shaped blocking spring link 25 is connected to the remaining end of the main lever 5, and the blocking spring link 25 moves up and down as the main shaft 4 rotates. A flange 34 is attached to the lower end of the cutoff spring link 25, and a cutoff spring (blocking member) 26 is wound around the cutoff spring link 25 using the flange 34 as a stopper. The upper end portion of the cutoff spring 26 is pressed by the housing 1.

  The roller 6 is in contact with the outer peripheral surface of a closing cam 3 described later of the closing control mechanism, and a load is transmitted from the closing cam 3 during the closing operation. The roller 7 can be engaged with a second blocking latch 8 connected to the blocking electromagnet 201. The 2nd interruption | blocking latch 8 is an open V-shape, and is rotatably supported by the housing | casing 1 in the center part. An engaging portion 8a that engages with the roller 7 is formed on one end side. A roller 10 is attached to the other end of the second blocking latch 8, and this roller 10 engages with the blocking latch 11. A return spring 9 is attached to the middle of the arm on the engagement portion 8 a side of the second blocking latch 8, and one end of the return spring 9 is fixed to the housing 1. The blocking latch 11 has substantially the same configuration as the second blocking latch 8 and is rotatably supported by the housing 1. An engaging portion 11a that engages with the roller 10 is formed on one end side of the V-shape, and a roller 13 that engages with the blocking trigger 14a is attached to the multi-end side. A return spring 12 having one end fixed to the housing 1 is attached to the middle of the arm on the roller 13 side.

  The interruption trigger 14a is L-shaped and can be rotated at a bent portion. A return spring 15 is attached to an intermediate portion of the arm portion extending in the horizontal direction. A blocking trigger 14b is attached to the rotation shaft 14c of the blocking trigger 14a. The plunger 211 of the blocking electromagnet 201 is brought into contact with the blocking trigger 14b, and the blocking spring 26 acts. The tip end of the arm extending in the vertical direction of the blocking trigger 14 a is engaged with the roller 13.

  The return springs 9, 12, and 15 provided on the second cutoff latch 8, the cutoff latch 11, and the cutoff trigger 14a are compressed from the free length of the spring in the state shown in FIG. These latches 8 and 11 and trigger 14a are always subjected to spring forces of 9, 12, and 15 when they are restored.

  In the state shown in FIG. 5, the spring force of the cutoff spring 26 tries to rotate the main lever 5 counterclockwise. However, since the roller 7 of the main lever 5 is engaged with the engaging portion 8a of the second blocking latch 8, this rotational movement is prevented. Similarly, the second shut-off latch 8 is also prevented from rotating since the roller 10 is engaged with the engaging portion of the shut-off latch 11. The blocking latch 11 is also prevented from rotating because the roller 13 is engaged with the vertical end of the blocking trigger 14a. As a result, in the shut-off control mechanism, the respective components engage with each other, and the spring force of the shut-off spring 26 is held without being released. In the breaking operation described later, the engagement between these components is released, the spring force of the breaking spring 26 is released, and the contact portion is opened.

  A large gear 52 is attached to the camshaft 2 at the closing spring portion. One end of the closing spring link 27 is attached to the large gear 52 eccentrically. The other end of the closing spring link 27 is connected to a spring receiver 35 that holds the closing spring 28 by a pin. A closing spring (closing member) 28 is inserted through the closing spring link 27. One end of the closing spring 28 is held by a spring receiver 35 and the other end is held by the housing 1. The large gear 52 meshes with the small gear 51 attached to the motor 50.

  A cam 3 that can be engaged with the roller 6 of the cutoff spring portion is also attached to the cam shaft 2. A roller 18 is attached to a substantially maximum diameter portion of the cam 3, and the engaging portion 19 a of the closing latch 19 is engaged with the roller 18. The closing latch 19 has a V shape, and a rotating shaft 19b is attached in the vicinity of the bent portion of the V shape. A return spring 20 having one end fixed to the housing is attached to an intermediate portion of the arm 19c different from the arm on which the engaging portion 19a is formed. A roller 21 is attached to the end of the arm 19c. A throwing trigger 22 is disposed so as to be engageable with the roller 21. The throwing trigger 22 is rotatable at the intermediate portion and has two arms. The tip of one arm can engage the roller 21, and the other arm can abut against the plunger 212 of the making electromagnet 202. A return spring 23 is attached to an intermediate portion of the arm on the plunger 212 side.

  Due to the spring force of the closing spring 28, a counterclockwise rotational force is applied to the cam 3 via the large gear 52 and the cam shaft 2. However, since the roller 18 is engaged with the engaging portion 19a of the closing latch 19, the rotation of the cam 3 is prevented. Similarly, since the roller 21 is engaged with the making trigger 22, rotation of the making latch 19 is prevented. Thus, since the components are engaged with each other in the closing control mechanism, the spring force of the closing spring 28 is held without being released.

  A series of operations of the operating device will be described below. FIG. 5 is a diagram showing the input state of the operating device, FIG. 6 is a diagram showing the shut-off state, FIG. 7 is a diagram showing the in-progress state, and FIG. In these drawings, the cutoff spring 26 and the closing spring 28 are both compression coil springs. In FIG. 5, these springs 26 and 28 are in a compressed state.

  When a shut-off command is input in the state of FIG. 5, the shut-off electromagnet 201 is excited. When the blocking electromagnet 201 is excited, the plunger 211 protrudes upward in FIG. 5 and pushes the blocking trigger 14b. The interruption trigger 14b rotates counterclockwise, and the engagement between the interruption trigger 14a and the interruption latch 11 is released.

  Since the engagement with the cutoff trigger 14a is released, the cutoff latch 11 is free to rotate. The roller 10 of the second blocking latch 8 pushes the blocking latch 11, and the blocking latch 11 rotates counterclockwise. The engagement between the blocking latch 11 and the second blocking latch 8 is released, and the second blocking latch 8 is free to rotate. Then, it rotates counterclockwise by the contact force of the main lever 5 and disengages from the main lever 5.

  Although the main lever 5 has stopped the movement of the cutoff spring link 25 that presses the cutoff spring 26, since this restriction of the main lever 5 has been eliminated, the cutoff spring 26 is released and pushes the cutoff spring link 25 downward. The main lever 5 rotates counterclockwise, the movable contact 32 moves downward, and the contact 29a, 29b is opened. FIG. 6 shows a state where the blocking operation has been completed. The roller 6 of the main lever 5 comes into contact with the cam 3 of the closing mechanism and comes to rest.

  The making operation for returning from the shut-off state to the making state shown in FIG. 5 will be described below. When the input command is input, the input electromagnet 202 is excited, and the plunger 212 protrudes downward in FIG. The plunger 212 presses one end of the making trigger 22. The pressed closing trigger 22 rotates counterclockwise to release the engagement with the closing latch 19. The closing latch 19 is pushed by the roller 18 of the cam 3 and rotates counterclockwise, and the engagement with the roller 18 is released. Since the restriction on the movement of the cam 3 is eliminated, the spring force of the closing spring 28 is released, and the closing spring link 27 moves downward. When the closing spring link 27 moves, the camshaft 2 and the large gear 52 rotate counterclockwise.

  Since the cam shaft 2 is rotated, the cam 3 is also rotated counterclockwise. Then, it contacts the roller 6 of the main lever 5 and rotates the main lever 5 clockwise. This state is shown in FIG. When the closing spring 28 is further released and the closing spring link 27 is pushed downward, the cam 3 continues to rotate counterclockwise. Since the cam 3 rotates the main lever 5 and the main shaft 4 in the clockwise direction, the cutoff spring link 25 connected to one arm of the main lever 5 moves upward and compresses the cutoff spring 26. When the cam 3 rotates approximately half a half from the stationary position, the maximum radius of curvature of the cam 3 comes into contact with the roller 6 of the main lever 5 and compresses the cutoff spring 26 to substantially the original position. At this time, the movable contact 32 connected to the main shaft 4 moves upward and closes the contact points 29a and 29b.

  In parallel with the closing operation between the contacts 29a and 29b, the levers of the shut-off control mechanism are returned. That is, the return spring 9 rotates the second cutoff latch 8 clockwise to return it to its original position. Similarly, the return spring 12 pushes the blocking latch 11 to return to the original position. The return spring 15 pushes the cutoff trigger 14 to return to the original position. Thereby, the making operation is completed. This state is shown in FIG.

  When the closing operation is completed, the closing spring 28 is compressed and returned to its original state. Specifically, the electric motor 50 is driven to rotate the small gear 51 clockwise. The large gear 52 that meshes with the small gear 51 rotates counterclockwise, and the closing spring link 27 moves upward. Since the closing spring link 27 has moved upward, the closing spring 28 is compressed. When the large gear 52 rotates approximately half a turn, a limit switch (not shown) stops the electric motor 50. At this time, the closing spring 28 tries to release the spring force. However, since the roller 18 of the cam 3 is engaged with the engaging portion 19a of the closing lever 19 and the closing lever 19 is engaged with the closing trigger 22, respectively. The spring 28 is held in a compressed state. The shut-off spring 26 and the closing spring 28 return to the original compression state, and the closing holding state shown in FIG. 5 is obtained.

  A detailed longitudinal sectional view of the electromagnets 201 and 202 used in the above embodiment is shown in FIG. In FIG. 1, the states before and after the operation of the plungers 211 and 212 are shown in the same drawing. That is, the left half of the figure is the state before the operation of the plungers 211 and 212 and the movable iron core 205, and the right half is the state after the operation.

A movable iron core 205 is fitted to plungers 211 and 212 made of a nonmagnetic metal, for example, austenitic stainless steel. The first fixed iron core 203 is arranged with a slight gap from the plungers 211 and 212. The second fixed iron core 204 and the movable iron core 205 are arranged adjacent to each other. A coil 208 is disposed on the outer peripheral side of the first fixed iron core 203 and the movable iron core 205, and a second fixed iron core 204 is disposed so as to cover the side surface portion and the outer peripheral portion of the coil 208. Nonmagnetic plates 207 are disposed on the side surfaces of the second fixed iron core 204 and the movable iron core 205.

  The second fixed iron core 204 is concave downward, and the first fixed iron core 203 is convex upward. The first fixed iron core 203 and the second fixed iron core 204 are formed with inlay portions. After combining the inlay portions, the first and second fixed iron cores 203 and 204 are fixed with bolts or the like. While the power circuit breaker is energized, a return spring (not shown) pushes the movable core 205 so that the top of the movable core 205 is in contact with the plate 207, and there is a gap between the movable core 205 and the first fixed core 203. A gap is formed in the axial direction.

The electromagnets 201 and 202 configured as described above operate as follows. When a breaker or closing command is input to the power breaker, power is supplied to the coil 208 from a power source (not shown) via the electric wire 209. The coil 208 magnetizes the first fixed iron core 203. The movable core 205 is attracted to the magnetized first fixed core 203 and moves downward, and the distance between the first fixed core 203 and the movable core 205 is reduced. The planners 211 and 212 to which the movable core 205 is attached also move downward, and push the triggers 14b and 22 shown in FIG. When the commanded operation is completed, a return spring that presses the movable core 205 returns the movable core 205 to the initial position.

  FIG. 2 shows an example of the magnetic characteristics of the magnetic material. The horizontal axis of the figure is the magnetic field strength H, and the unit is (A / m). The vertical axis represents the magnetic flux density B, and the unit is (T). The solid line (a) is the characteristic of the first material where the magnetic flux density is about 1.0 (T) when the magnetic field strength is 2000 (A / m), and the broken line (b) is the magnetic field strength. This is a characteristic of the second material in which the magnetic flux density exceeds about 1.5 (T) and the saturation magnetic flux density reaches about 2.0 (T) when is 2000 (A / m). As the first material, for example, SUS430, which is ferritic stainless steel, is used. Pure iron or 3% silicon steel is used as the second material.

  When all of the movable iron core 205 and the fixed iron cores 203 and 204 are made of the same material, it is preferable that the movable iron core 205 and the fixed iron cores 203 and 204 are made of a second material having a higher magnetic permeability than the first material. This is because the generated suction force is large and the operation time of the plunger is increased. The specific resistance of the first and second materials is about 0.99 (μ · Ω · m) for SUS430 and about 0.47 (μ · for 3% silicon steel when compared between SUS430 and 3% silicon steel. It is about twice as large as (Ω · m). Therefore, the use of the first material requires a smaller current value, and the loss due to eddy current is also small.

  FIG. 3 shows the time change of the current flowing through the coil. The horizontal axis is time, and the unit is (s). The vertical axis represents current, and the unit is (A). The steady current is a value obtained by dividing the control voltage by the total resistance of the control circuit. If the steady-state current value is larger than the specified value with only the coil resistance, adjust the resistance by inserting a resistance in series with the coil.

  The operating state of the plungers 211 and 212 can be estimated from the current change. Shut off or turn on is commanded at time zero. Since the coil 208 has an inductance, even if a voltage is applied to the magnetic circuit including the coil 208, the current does not immediately reach a steady value. Due to the time constant of the magnetic circuit including the coil 208, the current rises as shown in FIG. When the plungers 211 and 212 start to move, the distance between the fixed iron core 203 and the movable iron core 205 decreases. As a result, the inductance increases and the current of the coil 208 decreases.

  As time further elapses, the current decreases, and a recessed point A may appear in the current waveform. Point A is a state in which the plungers 211 and 212 have made full strokes to push the trigger levers 14 b and 22, and no load is applied to the plungers 211 and 212 from the trigger levers 14 b and 22. Thereafter, the current rises toward the steady current. The time from the moment when the input or shut-off command is commanded to the point A is the operating time of the plungers 211 and 212.

  When the iron core is formed by combining only the second materials having good magnetic characteristics and low specific resistance, the maximum current value until reaching point A is large as shown in the thin line (a), and the operation time of the plunger is large. short. On the other hand, in the iron core composed of only the first material having a magnetic property worse than that of the first material and having a large specific resistance, as shown by the thick line (b), the rise of current and the magnetization of the iron core are slow. In this case, a sufficient suction force cannot be obtained, and the plungers 211 and 212 may stagnate without pressing the trigger levers 14 b and 22.

  When the iron core is configured by combining the first and second materials, as shown by the broken line (c), the rise of the current is slower than that of the thin line (a), but the electromagnets (plungers 211 and 212 that satisfy the opening characteristics) are satisfied. ) Can be shortened. By changing the combination of the materials of the iron core, the operation time of the plungers 211 and 212 can be increased or decreased.

  According to the present embodiment, various attractive forces of the electromagnets 201 and 202 are set by using a combination of materials having different magnetic permeability and specific resistance for the movable cores 205 and the fixed cores 203 and 204 of the electromagnets 201 and 202, respectively. it can. As a result, the operation time of the plungers 211 and 212 can be adjusted. Thereby, when the flat part of the width W formed in the edge part of the interruption | blocking trigger 14a acts as an engagement allowance, adjustment with the roller 13 and this flat part becomes unnecessary, and operation | movement stability of the operating device of the circuit breaker for electric power is stabilized. Increase reliability and improve reliability.

  Several modifications of the electromagnet according to the present invention are shown in longitudinal sectional views in FIGS. In these drawings, the left side is a diagram before the operation of the electromagnet, and the right side is a diagram after the operation. In the above-described embodiment, the fixed iron core is composed of the first fixed iron core 203 on the inner peripheral side and the second fixed iron core 204 on the outer peripheral side. However, in the modification shown in FIG. The upper fixed iron core 204a and the lower fixed iron core 203a divided into two in the direction are configured. The coil 208 is accommodated in the lower fixed iron core 203a.

  The movable iron core is also composed of movable iron cores 205a and 205b divided into two in the axial direction. As a result, the combination of materials having different magnetic characteristics increases, and the design likelihood increases. In addition, when adjusting the operation time of the plungers 211 and 212, it is preferable to change the material of the movable iron core 205b appropriately.

  In the embodiment shown in FIG. 1, an example in which the second fixed iron is divided into two in the axial direction and the first fixed iron core is formed in a cylindrical shape is shown in FIG. The divided second fixed iron cores 204b1 and 204b2 form an annular space with the first fixed iron core 203b in order to hold the coil 208. Further, in order to hold the fixed iron cores 204b2 and 203b, a non-magnetic plate 210 is provided on the lower side surface of the fixed iron cores 204b2 and 203b. Also in this modification, the operation time of the plungers 211 and 212 can be adjusted. According to this modification, since the fixed iron core 203b is provided on the inner side of the coil 208, the fixed iron core 203b can be magnetized early on the inner peripheral side where the magnetic force is stronger, and the rise of the action of attracting the movable iron core 205 is quick. Become.

In the example shown in FIG. 10, the example which made the side part of the movable iron core and the fixed iron core adjacent to it conical is shown in FIG. The inner side surface portion of the fixed iron core 203c is formed in a conical shape, and the surface adjacent to the fixed iron core 203c of the movable iron core 205c is formed by a conical surface having the same inclination as this conical surface. When changing from the example shown in FIG. 10 to the shape shown in FIG. 11, a bolt or the like (not shown) that connects the fixed iron cores 203b, 204b2 and the plate 210 may be removed. Therefore, it is easy to structural change, the relationship between the axial distance between the attraction force between the fixed iron core 203c movable core 205 c is changed.

  When the changes shown in FIGS. 9 to 11 are applied to the electromagnets 201 and 202, the attractive force characteristics that are the characteristics of the distance between the iron cores and the attractive force in the electromagnets 201 and 202 can be easily changed. As a result, the operation time of the plungers 211 and 212 can be easily adjusted with one electromagnet. In addition, the operation time of the plungers 211 and 212 can be increased.

  FIG. 12 shows an example in which one movable iron core is used without dividing the movable iron core in the example shown in FIG. In the electromagnets 201 and 202, a gap is formed in the spigot connection between the fixed iron core 203 and the fixed iron core 204. The axial length of the spigot portion of the fixed iron core 203d is made longer than the corresponding length of the fixed iron core 204a to reduce the cross-sectional area, thereby limiting the magnetic flux flowing from the fixed iron core 203 to the fixed iron core 204. According to this modification, the attractive force generated by the electromagnets 201 and 202 is smaller than that in the example shown in FIG. As a result, the operation time of the plungers 211 and 212 can be adjusted late.

  FIG. 13 is a schematic diagram showing an electrical circuit connected to the shutoff control mechanism and the closing control mechanism of the above embodiment. A control power source 306 is connected to the coil 208 of the blocking or closing electromagnets 201 and 202. A capacitor 304 is connected in series to the coil 208 of the electromagnets 201 and 202, and a resistor 305 is connected in parallel to the capacitor 304. Since the sum of the internal resistance of the coil 208 and the resistance 305 is the total resistance of the circuit, the value of the resistance 305 is determined so as to satisfy the regulation of the steady current. A large current flows transiently through the coil 208 from the moment the power supply voltage is applied by inputting a closing command or a shut-off command. As a result, the rising of the suction force is accelerated, and the operation time of the plungers 211 and 212 is accelerated.

  Although the gas breaker using SF6 gas has been described in the above embodiments and modifications, it goes without saying that other switchgear such as a vacuum circuit breaker may be used.

The longitudinal cross-sectional view of one Example of the electromagnet with which the circuit breaker for electric power which concerns on this invention is provided. The figure explaining a magnetization curve. The figure explaining coil current. The side view of one Example of the circuit breaker for electric power which concerns on this invention. The schematic diagram of the interruption | blocking spring part and closing spring part of the circuit breaker for electric power shown in FIG. The figure explaining operation | movement of a closing spring part and a cutoff spring. The figure explaining operation | movement of a closing spring part and a cutoff spring. The figure explaining operation | movement of a closing spring part and a cutoff spring. The longitudinal cross-sectional view of the modification of the electromagnet which the circuit breaker for electric power which concerns on this invention has. The longitudinal cross-sectional view of the other modification of the electromagnet which the circuit breaker for electric power which concerns on this invention has. The longitudinal cross-sectional view of the further another modification of the electromagnet which the circuit breaker for electric power which concerns on this invention has. The longitudinal cross-sectional view of the further another modification of the electromagnet which the circuit breaker for electric power which concerns on this invention has. The schematic diagram of the control part with which the circuit breaker for electric power is provided.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Housing, 2 ... Cam shaft, 3 ... Cam, 4 ... Main shaft, 5 ... Main lever, 8 ... 2nd interruption | blocking latch, 11 ... interruption | blocking latch, 14 ... interruption | blocking trigger, 19 ... closing latch, 22 ... closing trigger, DESCRIPTION OF SYMBOLS 100 ... Circuit breaker for electric power, 201 ... Electromagnet for interruption, 202 ... Electromagnet for insertion, 203, 203a ... Fixed iron core, 204 ... Second fixed iron core, 205 ... Movable iron core, 208 ... Coil, 211, 212 ... Plunger, 300 ... electric circuit, 304 ... capacitor, 305 ... resistor, 306 ... control power source.

Claims (2)

A shut-off unit that opens and closes a contact having a fixed contact and a movable contact to switch off and on power, a shut-off member and a feed member that open and close the contact, and a driving force by the shut-off member and the feed member is retained or released. In a power circuit breaker including a shut-off control mechanism and a closing control mechanism that perform, and an electromagnet including a coil that is excited by a shut-off command or a closing command, and having a fixed iron core and a movable iron core, the electromagnet is capable of linear motion A plunger, a movable iron core attached to the plunger, and metal first and second fixed iron cores adjacent to the movable iron core, the first fixed iron core penetrating the plunger and having one end side opposite the one end side in the axial direction of the movable core, the second fixed iron core is solid the other end of the first with one end side to face with a gap on an outer peripheral portion of the movable iron core The first and second fixed iron cores are connected to the other end side of the iron core, and are made of metal materials having different magnetic characteristics and specific resistance, and the outer periphery of the first fixed iron core and the second An annular recess for accommodating the coil is formed between the first fixed iron core and the first fixed iron core is formed in a cylindrical shape and arranged on the inner peripheral side of the second fixed iron core. A plate that is coupled to the side surfaces of the first and second fixed iron cores is provided, and the first fixed iron core is detachable by releasing the coupling between the plate and the first and second fixed iron cores. Power circuit breaker. A shut-off unit that opens and closes a contact having a fixed contact and a movable contact to switch off and on power, a shut-off member and a feed member that open and close the contact, and a driving force by the shut-off member and the feed member is retained or released. In a power circuit breaker including a shut-off control mechanism and a closing control mechanism that perform, and an electromagnet including a coil that is excited by a shut-off command or a closing command, and having a fixed iron core and a movable iron core, the electromagnet is capable of linear motion A plunger, a movable iron core attached to the plunger, and metal first and second fixed iron cores adjacent to the movable iron core, the first fixed iron core penetrating the plunger and having one end side opposite the one end side in the axial direction of the movable core, the second fixed iron core is solid the other end of the first with one end side to face with a gap on an outer peripheral portion of the movable iron core The first and second fixed iron cores are connected to the other end side of the iron core, and are made of metal materials having different magnetic characteristics and specific resistance, and the outer periphery of the first fixed iron core and the second An annular recess that accommodates the coil is formed between the first fixed iron core and the second fixed iron core in a spigot shape, and the axial length of the spigot portion is determined. A power circuit breaker characterized in that the first fixed iron core is longer than the second fixed iron core to increase the volume of the recess of the coil.

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