JP5537365B2 - Load tap changer - Google Patents

Description

  Embodiments described herein relate generally to an on-load tap switching device that switches taps in a load state.

  In recent years, a tap switching device under load has a high demand for using a vacuum valve in a switching switch part from the aspects of maintenance and durability. Further, the on-load tap switching device has conventionally been required to save space, cost and high capacity. In recent years, such a request is large in transformers for substation facilities installed in urban areas.

  In general, a high-capacity vacuum valve type on-load tap changer often uses two or four valves corresponding to one. However, an increase in the number of valves is an obstacle to saving space and cost.

  In view of this, a one-valve type tap changer at load using one valve per one is known.

JP 61-79210 A JP-A 61-79211

  However, the known one-valve type on-load tap changer has a large cutoff current due to the vacuum valve. For this reason, a large-capacity and large-sized vacuum valve must be used for the on-load tap switching device, and the purpose of saving space or cost of the on-load tap switching device cannot be sufficiently fulfilled.

  On the other hand, the electric circuit of the on-load tap switching device that suppresses the breaking current is disclosed. However, such an electric circuit is not suitable for practical use because it has many components, a circuit is complicated, and control is complicated. That is, if a load tap changer having a structure satisfying such an electric circuit is manufactured, the load tap changer is increased in size or the manufacturing cost is increased.

  SUMMARY OF THE INVENTION An object of the present invention is to provide a one-valve type tap changer at load that is suitable for practical use by suppressing the cutoff current of the valve.

An on-load tap switching device according to an aspect of the present invention includes a first contact connected to a first tap, a second contact connected to a second tap, and the first contact. Alternatively, the second contact and one end are electrically connected to switch to the first contact or the second contact, and the first switch connected to the other end of the first switch. A common contact, a third contact electrically connected to the first contact, a fourth contact electrically connected to the second contact, and one end serving as the first common contact. A resistor connected, a fifth contact connected to the other end of the resistor, the third contact, the fourth contact, or the fifth contact and one end thereof are electrically connected to the third contact. contact, a second changeover switch for switching said fourth contact or the fifth contact, the first A second common contact connected to the other end of the changeover switch, the valve having one end connected to said second common contact is connected to the other end of said valve, said first tap and said A third common contact connected to a location that serves as a reference potential of the second tap, a sixth contact electrically connected to the third contact,
A seventh contact electrically connected to the fourth contact; an eighth contact electrically connected to the fifth contact; the sixth contact; the seventh contact; 8 contacts and one end are electrically connected to switch to the sixth contact, the seventh contact or the eighth contact, and the other switch is connected to the third common contact. A switch for switching from the second tap to the first tap, after the second changeover switch is switched to the fourth contact, the first changeover switch is As a preliminary operation for switching to the second contact and switching from the first tap to the second tap, after the second changeover switch has switched to the third contact, the first contact changeover switch is switched to the first contact

The electric circuit diagram which shows the state by which A tap of the tap change apparatus at the time of load which concerns on embodiment of this invention was selected. The electric circuit diagram which shows the 1st state in the switching operation from A tap to B tap of the tap switching apparatus at the time of load which concerns on this embodiment. The electric circuit diagram which shows the 2nd state in the switching operation from A tap to B tap of the tap switching apparatus at the time of load which concerns on this embodiment. The electric circuit diagram which shows the 3rd state in switching operation from A tap to B tap of the tap switching apparatus at the time of load which concerns on this embodiment. The electric circuit diagram which shows the 4th state in switching operation from A tap to B tap of the tap switching apparatus at the time of load which concerns on this embodiment. The electric circuit diagram which shows the 5th state in the switching operation from A tap to B tap of the tap switching apparatus at the time of load which concerns on this embodiment. The electric circuit diagram which shows the 6th state in switching operation from A tap to B tap of the tap switching apparatus at the time of load which concerns on this embodiment. The electric circuit diagram which shows the 7th state in the switching operation from A tap to B tap of the tap switching apparatus at the time of load which concerns on this embodiment. The electric circuit diagram which shows the state by which B tap of the tap change apparatus at the time of load which concerns on this embodiment was selected. The electric circuit diagram which shows the 1st state in the switching operation from B tap to A tap of the tap change apparatus at the time of load which concerns on this embodiment. The electric circuit diagram which shows the 2nd state in the switching operation | movement from B tap to A tap of the tap switching apparatus at the time of load which concerns on this embodiment. The electric circuit diagram which shows the 3rd state in the switching operation from B tap to A tap of the tap switching apparatus at the time of load which concerns on this embodiment. The electric circuit diagram which shows the 4th state in the switching operation from B tap to A tap of the tap switching apparatus at the time of load which concerns on this embodiment. The electric circuit diagram which shows the 5th state in the switching operation from B tap to A tap of the tap switching apparatus at the time of load which concerns on this embodiment. The electric circuit diagram which shows the 6th state in the switching operation from B tap to A tap of the tap switching apparatus at the time of load concerning this embodiment. The electric circuit diagram which shows the 7th state in the switching operation from B tap to A tap of the tap switching apparatus at the time of load which concerns on this embodiment. The sequence diagram which shows the control which transfers to each state of the resistance change switch by the tap change operation | movement which concerns on this embodiment, a VCB change switch, an electricity supply change switch, and VCB. The block diagram which shows the whole structure of the tap switching apparatus at the time of load which concerns on this embodiment. The block diagram which looked at the connection structure of the fixed terminal pattern which concerns on this embodiment, VCB, and the current limiting resistor from the outside. The lineblock diagram showing the composition of the resistance changeover switch concerning this embodiment, the VCB changeover switch, and the energization changeover switch. The block diagram which shows the contact state of the resistance changeover switch which concerns on this embodiment, a VCB changeover switch, and an electricity supply changeover switch, and a fixed terminal pattern. The block diagram which looked at the connection structure of the fixed terminal pattern which concerns on this embodiment, VCB, and current limiting resistance from the inner side. The block diagram which shows the mechanism which drives VCB which concerns on this embodiment. The block diagram which shows the structure which drives the VCB selector switch and energization selector switch which concern on this embodiment. The block diagram which shows the state protruded to the upper part of the electricity supply cam stopper which concerns on this embodiment. The block diagram which shows the state in which the electricity supply cam stopper which concerns on this embodiment is accommodated in the bottom part. The block diagram which shows the whole structure of the phase adjustment mechanism of the electricity supply switch concerning this embodiment.

  Embodiments of the present invention will be described below with reference to the drawings.

(Embodiment)
1 to 16 are electric circuit diagrams showing states STA to ST7A and STB to ST7B in the tap switching operation of the on-load tap switching device 1 according to the embodiment of the present invention. In addition, about the tap switching apparatus 1 at the time of load, the structure for one phase is demonstrated among three phases, and description is abbreviate | omitted on the assumption that the other two phases are comprised similarly. Also, the same parts in the drawings are denoted by the same reference numerals, detailed description thereof is omitted, and different parts are mainly described.

  The on-load tap changer 1 includes a resistance changeover switch SW1, a VCB changeover switch SW2, an energization changeover switch SW3, a current limiting resistor 2, and a VCB (vacuum valve, vacuum circuit breaker) 3.

  The A contact of the resistance changeover switch SW1 and the A contact of the VCB changeover switch SW2 are short-circuited. The A contact of the VCB changeover switch SW2 and the A contact of the energization changeover switch SW3 are short-circuited. That is, the A contacts of the resistance changeover switch SW1, the VCB changeover switch SW2, and the energization changeover switch SW3 are all electrically connected.

  The B contact of the resistance changeover switch SW1 and the B contact of the VCB changeover switch SW2 are short-circuited. The B contact of the VCB changeover switch SW2 and the B contact of the energization changeover switch SW3 are short-circuited. That is, the B contacts of the resistance changeover switch SW1, VCB changeover switch SW2, and energization changeover switch SW3 are all electrically connected.

  An A tap is connected to the A contact of the resistance changeover switch SW1. A B tap is connected to the B contact of the resistance changeover switch SW1. The common contact (common) of the resistance changeover switch SW1 is connected to the R contact of the VCB changeover switch SW2 via the current limiting resistor 2.

  The R contact of the VCB changeover switch SW2 is short-circuited with the R contact of the energization changeover switch SW3. The common contact of the VCB changeover switch SW2 is connected to the common contact of the energization changeover switch SW3 via the VCB3.

  A common contact of the energization selector switch SW3 is connected to the neutral point N of the transformer. The neutral point N is a location that indicates a potential (for example, 0 volts) that serves as a reference for the tap voltages of the A tap and the B tap.

  FIG. 17 is a sequence diagram showing control for shifting to each state of the resistance changeover switch SW1, the VCB changeover switch SW2, the energization changeover switch SW3, and the VCB3 by the tap changeover operation. The switching operation from the A tap to the B tap is indicated by a solid line. The switching operation from the B tap to the A tap is indicated by a broken line.

  First, the switching operation from the A tap to the B tap of the on-load tap switching device 1 will be described with reference to FIGS.

  The state STA of the on-load tap switching device 1 shown in FIG. 1 is a normal state in which the A tap is selected. The state STA is a state in which the resistance changeover switch SW1, the VCB changeover switch SW2, and the energization changeover switch SW3 all select the A contact and the VCB3 is turned on. At this time, since VCB3 has a contact resistance, almost no current flows through VCB3. Instead, the load current (transformer main winding current) IL flows through a path that short-circuits the A contact of the VCB changeover switch SW2 connected in parallel with the VCB3 and the A contact of the energization changeover switch SW3.

  In the first-stage switching operation, the energization selector switch SW3 switches from the A contact to the R contact. There is no interruption of current by this switching operation. As a result, the on-load tap switching device 1 changes from the state STA shown in FIG. 1 to the state ST1A shown in FIG. In the state ST1A, the load current IL flows through the VCB3. Since the R contact of the VCB changeover switch SW2 and the common contact of the resistance changeover switch SW1 are connected to the current limiting resistor 2, current hardly flows from the R contact side of the energization changeover switch SW3.

  In the second stage switching operation, VCB3 is opened. At this time, VCB3 cuts off load current IL. Thereby, the on-load tap switching device 1 changes from the state ST1A shown in FIG. 2 to the state ST2A shown in FIG. In the state ST2A, the load current IL flows through the current limiting resistor 2.

  In the switching operation at the third stage, the VCB selector switch SW2 is switched from the A contact to the R contact. Thereby, the on-load tap switching device 1 changes from the state ST2A shown in FIG. 3 to the state ST3A shown in FIG.

  In the switching operation at the fourth stage, VCB3 is turned on. Thereby, the on-load tap switching device 1 changes from the state ST3A shown in FIG. 4 to the state ST4A shown in FIG. However, since VCB3 has contact resistance, almost no current flows through VCB3.

  In the fifth stage switching operation, the energization selector switch SW3 is switched from the R contact to the B contact. There is no interruption of current by this switching operation. Thereby, the on-load tap switching device 1 changes from the state ST4A shown in FIG. 5 to the state ST5A shown in FIG. In the state ST5A, a bridge is formed between the A tap and the B tap. At this time, the load current IL does not flow to the VCB 3 due to the current limiting resistor 2. Therefore, the load current IL flows from the B contact of the energization changeover switch SW3 to the B tap. On the other hand, a step voltage Us is generated between the A tap and the B tap due to the bridging state. Accordingly, the circulating current Ic flows between the A tap and the B tap via the current limiting resistor 2 and the VCB 3.

  In the switching operation at the sixth stage, VCB3 is opened. At this time, VCB3 cuts off circulating current IC. Thereby, the on-load tap switching device 1 changes from the state ST5A shown in FIG. 6 to the state ST6A shown in FIG. In the state ST6A, the on-load tap switching device 1 is switched to the B tap.

  In the switching operation at the seventh stage, the VCB selector switch SW2 is switched from the R contact to the B contact. In the switching operation of the eighth stage, the resistance selector switch SW1 is switched from the A contact to the B contact, and VCB3 is turned on. Thereby, the on-load tap switching device 1 changes from the state ST6A shown in FIG. 7 to the state STB shown in FIG. 9 through the state ST7A shown in FIG. The switching operation in the seventh stage and the eighth stage is an operation for preparing in advance for the on-load tap switching device 1 to next switch from the B tap to the A tap. The state STB is a normal state in which the B tap is selected.

  In this way, the switching operation from the A tap to the B tap of the on-load tap switching device 1 is performed.

  Next, a switching operation from the B tap to the A tap of the on-load tap switching device 1 will be described with reference to FIGS. Note that the basic content of the switching operation from the B tap to the A tap is the same as the switching operation from the A tap to the B tap, and a detailed description thereof will be omitted.

  The state STB of the on-load tap switching device 1 shown in FIG. 9 is a normal state in which the B tap is selected. The state STB is a state in which the resistance changeover switch SW1, the VCB changeover switch SW2, and the energization changeover switch SW3 all select the B contact and the VCB3 is turned on.

  In the first-stage switching operation, the energization selector switch SW3 is switched from the B contact to the R contact. Thereby, the on-load tap switching device 1 changes from the state STB shown in FIG. 9 to the state ST1B shown in FIG.

  In the second stage switching operation, VCB3 is opened. At this time, VCB3 cuts off load current IL. Thereby, the on-load tap switching device 1 changes from the state ST1B shown in FIG. 10 to the state ST2B shown in FIG.

  In the switching operation at the third stage, the VCB selector switch SW2 is switched from the B contact to the R contact. Thereby, the on-load tap switching device 1 changes from the state ST2B shown in FIG. 11 to the state ST3B shown in FIG.

  In the switching operation at the fourth stage, VCB3 is turned on. Thereby, the on-load tap switching device 1 changes from the state ST3B shown in FIG. 12 to the state ST4B shown in FIG.

  In the fifth stage switching operation, the energization selector switch SW3 is switched from the R contact to the A contact. Thereby, the on-load tap switching device 1 changes from the state ST4B shown in FIG. 13 to the state ST5B shown in FIG. In the state ST5B, the A tap and the B tap are bridged.

  In the switching operation at the sixth stage, VCB3 is opened. At this time, VCB3 cuts off circulating current IC. Thereby, the on-load tap switching device 1 changes from the state ST5B shown in FIG. 14 to the state ST6B shown in FIG.

  In the switching operation at the seventh stage, the VCB selector switch SW2 is switched from the R contact to the A contact. In the switching operation at the eighth stage, the on-load tap switching device 1 is switched from the B contact to the A contact, and the VCB 3 is turned on. Thereby, the on-load tap switching device 1 changes from the state ST6B shown in FIG. 15 to the state STA shown in FIG. 1 through the state ST7B shown in FIG.

  In this way, the switching operation from the B tap to the A tap of the on-load tap switching device 1 is completed.

  18 to 27 are configuration diagrams illustrating the configuration of the on-load tap switching device 1 according to the present embodiment.

  FIG. 18 is a configuration diagram showing the overall configuration of the on-load tap switching device 1. FIG. 19 is a configuration diagram of the connection configuration of the fixed terminal pattern 13, VCB 3, and current limiting resistor 2 as viewed from the outside. FIG. 20 is a configuration diagram showing configurations of the resistance changeover switch SW1, the VCB changeover switch SW2, and the energization changeover switch SW3. FIG. 21 is a configuration diagram showing a contact state between the resistance changeover switch SW1, the VCB changeover switch SW2, the energization changeover switch SW3, and the fixed terminal pattern 13. FIG. 22 is a configuration diagram of the connection configuration of the fixed terminal pattern 13, the VCB 3, and the current limiting resistor 2 as viewed from the inside. FIG. 23 is a configuration diagram showing a mechanism for driving the VCB. FIG. 24 is a configuration diagram showing a configuration for driving the VCB selector switch SW2 and the energization selector switch SW3.

  The overall configuration of the on-load tap switching device 1 will be described with reference to FIGS. 18 and 19.

  The external shape of the on-load tap switching device 1 is a shape close to a cylinder. The drive transmission shaft 7 is provided so as to penetrate the center portion of the circle of the cylindrical tap changing device 1 under load. An upper mounting plate 4 is attached to the upper part of the on-load tap switching device 1 so as to cover the upper surface. On the upper mounting plate 4, a storage mounting plate 9 is provided. The energy storage mechanism 10 is mounted on the energy storage mounting plate 9. A lower mounting plate 6 is attached to the lower part of the on-load tap switching device 1 so as to cover the bottom surface.

  The configuration for one phase of the on-load tap switching device 1 is a one-segment configuration in which a cylindrical portion having the upper mounting plate 4 as an upper surface is divided into three at a 120 degree angle from the center of the circle in the longitudinal direction. Hereinafter, the configuration for one phase will be mainly described. Description of other two-phase configurations is omitted because they are configured in the same manner.

  The drive cam 8 is directly connected to the drive transmission shaft 7. The accumulator mechanism 10 is a power source that rotates the drive transmission shaft 7 by the stored energy. The drive cam 8 rotates when the energy storage mechanism 10 rotates the drive transmission shaft 7. As the drive cam 8 rotates, the VCB 3, the resistance changeover switch SW1, the VCB changeover switch SW2, and the energization changeover switch SW3 are driven. When the drive transmission shaft 7 rotates, the on-load tap switching device 1 performs a tap switching operation. The on-load tap switching device 1 switches the switching operation from the A tap to the B tap and the switching operation from the B tap to the A tap by switching between normal rotation and inversion of the drive transmission shaft 7.

  A fixed terminal base plate 5 is attached to the outer peripheral portion of the on-load tap switching device 1. The current limiting resistor 2 and the VCB 3 are housed inside the fixed terminal base plate 5. The current limiting resistor 2 has two configurations, but may be configured with one, or may be configured with three or more. On the outside of the fixed terminal base plate 5, lead terminals 17, 18, 19 for connecting to the A tap, the B tap, and the neutral point N are provided. A fixed terminal pattern 13 is formed inside the fixed terminal base plate 5. The fixed terminal pattern 13 is obtained by patterning a fixed contact portion corresponding to each of the resistance changeover switch SW1, the VCB changeover switch SW2, and the energization changeover switch SW3 on the substrate.

  As shown in FIG. 22, the fixed terminal pattern 13 is divided into an upper resistance pattern 13a, a VCB movable portion pattern 13b, a lower resistance pattern 13c, an A tap pattern 13d, a neutral point pattern 13e, and a B tap pattern 13f. .

  The on-resistance pattern 13 a is connected to the upper terminal of the current limiting resistor 2 by the on-resistance connection line 15. The VCB movable part pattern 13b is connected to the movable part side terminal of the VCB 3 by a VCB movable part connection line 16. The lower resistance pattern 13 c is connected to the lower terminal of the current limiting resistor 2 by the lower resistance connection line 19. The A tap pattern 13d is connected to the A tap. The neutral point pattern 13e is connected to the neutral point N. Further, the neutral point pattern 13e is connected to a terminal on the fixed portion side of the VCB 3 by a VCB fixed connection line 20. The B tap pattern 13f is connected to the B tap.

  The resistance changeover switch SW1, the VCB changeover switch SW2, and the energization changeover switch SW3 will be described with reference to FIGS.

  The resistance changeover switch SW1 switches the connection of the current limiting resistor 2 between the A tap side and the B tap side. The resistance switch SW1 includes a contact 33 for resistance switching A contact, a contact 34 for resistance switching B contact, a resistance switching lever 12, a toggle lever 11, and a toggle spring 21.

  The resistance switching A contact 33 and the resistance switching B contact 34 are connected to the resistance switching lever 12. The resistance switching lever 12 moves according to the operation of the resistance switching lever driving pin 51 provided on the upper surface of the drive cam 8. The toggle lever 11 and the toggle spring 21 are provided such that the longitudinal direction extends from the center of the drive transmission shaft 7 in the outer peripheral direction. The toggle lever 11 and the toggle spring 21 are mechanisms for making the resistance changeover switch SW1 a toggle switch.

  The resistance switching lever 12 is driven by the operation of the resistance switching lever driving pin 51 as the driving cam 8 rotates. When the resistance switching lever 12 is driven, the resistance switching switch SW1 performs a switching operation.

  As shown in FIG. 17, the resistance changeover switch SW1 has a different sequence in the switching operation from the A tap to the B tap and the switching operation from the B tap to the A tap. Specifically, in the resistance changeover switch SW1, the contact changeover is delayed in the tap changeover operation. The toggle mechanism adjusts the timing of this delay operation. As a result of this adjustment, the resistance changeover switch SW1 has the necessary phase adjustment by switching between the switching operation from the A tap to the B tap and the switching operation from the B tap to the A tap (switching during normal rotation and inversion). The

  The VCB selector switch SW2 switches the connection of the VCB3 to any one of the A tap side, the current limiting resistor side, and the B tap side. The VCB changeover switch SW2 includes a VCB change B contact lever 36, a VCB change R contact lever 37, a VCB change A contact lever 38, a VCB change B contact contact 52, a VCB change R contact contact 53, and a VCB. A contact 54 for switching A contact is provided. Each VCB switching contact 52-54 is connected to each VCB switching lever 36-38, respectively. A biasing spring 35 is attached to the VCB switching levers 36 to 38.

  As shown in FIG. 24, cam profiles corresponding to the respective VCB switching levers 36 to 38 are formed on the side surface of the drive cam 8. The cam profile is formed by a VCB switching B contact cam 81, a VCB switching R contact cam 82, and a VCB switching A contact cam 83 provided on the drive cam 8. Each VCB switching cam 81-83 has a protruding shape. The VCB switching levers 36 to 38 are operated by the rotation of the respective VCB switching cams 81 to 83 having a protruding shape. The VCB switching levers 36 to 38 turn around the switching lever shaft 31. The VCB switching levers 36 to 38 operate using the elastic force of the biasing spring 35 that is repelled by the spring receiving plate 32. Each cam profile is formed so that the VCB changeover switch SW2 is switched according to the sequence shown in FIG.

  Each VCB switching lever 36 to 38 operates according to the shape of each cam profile that changes as the drive cam 8 rotates. When the VCB selector levers 36 to 38 operate, the VCB selector switch SW2 performs a switching operation.

  As shown in FIG. 17, the VCB changeover switch SW2 has the same sequence of the switching operation from the A tap to the B tap and the switching operation from the B tap to the A tap. Accordingly, the VCB selector switch SW2 is configured to be reversible between forward rotation and reverse rotation.

  The energization changeover switch SW3 switches the connection of the energizing contact to be energized with the neutral point N to either the tap side, the current limiting resistor side, or the B tap side. The energization switching switch SW3 includes an energization switching A contact lever 39, an energization switching R contact lever 40, an energization switching B contact lever 41, an energization switching A contact contact 55, an energization switching R contact contact 56, and an energization switch. A contact 57 for switching B contact is provided. Each energization switching contact 55-57 is connected to each energization switching lever 39-41, respectively. A biasing spring 35 is attached to each energization switching lever 39-41.

  As shown in FIG. 24, an energization cam main body 90 is provided on the side surface of the drive cam 8. The energization cam body 90 is formed with a cam profile corresponding to each of the energization switching levers 39 to 41. The cam profile is formed by an energization switching A contact cam 84, an energization switching R contact cam 85, and an energization switching B contact cam 86 provided in the energization cam main body 90. Each energization switching cam 84-86 has a projection shape. The energization switching levers 39 to 41 are operated by rotating the projection-shaped energization switching cams 84 to 86, respectively. The energization switching levers 39 to 41 turn around the switching lever shaft 31. The energization switching levers 39 to 41 operate using the elastic force of the urging spring 35 that is repelled by the spring receiving plate 32. Each cam profile is formed such that the energization selector switch SW3 performs a switching operation according to the sequence shown in FIG.

  Each energization switching lever 39 to 41 operates according to the shape of each cam profile that changes as the drive cam 8 rotates. When the energization switching levers 39 to 41 are operated, the energization switching switch SW3 performs a switching operation.

  As shown in FIG. 17, the energization changeover switch SW3 has different sequences depending on the switching operation from the A tap to the B tap and the switching operation from the B tap to the A tap. The energization cam main body 90 is configured to rotate separately from the drive cam 8. The energization cam body 90 rotates relative to the drive cam 8 during the tap switching operation. As a result, the energization cam body 90 moves relative to the drive cam 8 in the rotational direction of the energy storage mechanism 10. When the energization cam body 90 moves relative to the drive cam 8, the energization changeover switch SW3 switches between the switching operation from the A tap to the B tap and the switching operation from the B tap to the A tap (forward rotation). The necessary phase adjustment is performed by switching between time and reversal).

  A mechanism for adjusting the phase of the energization selector switch SW3 will be described with reference to FIGS.

  25 to 27 are configuration diagrams showing a phase adjustment mechanism for controlling the drive of the energization cam body 90 by adjusting the phase of the energization changeover switch SW3. FIG. 25 is a configuration diagram showing a state of protruding from the upper portion of the energizing cam stopper 87. FIG. 26 is a configuration diagram showing a state where the energization cam stopper 87 is housed in the bottom. FIG. 27 is a configuration diagram showing the overall configuration of the phase adjustment mechanism.

  An energization cam stopper cam portion 88 is provided on the outer peripheral side of the lower portion of the drive cam 8. Two energizing cam stopper cam grooves 93 are formed in the energizing cam stopper cam portion 88. The two energizing cam stopper cam grooves 93 are formed for forward rotation and reverse rotation, respectively.

  Two energizing cam stoppers 87 are provided below the drive cam 8. The two energizing cam stoppers 87 are for forward rotation and reverse rotation, respectively. Each energizing cam stopper 87 is provided with an energizing cam stopper spring 92. The energizing cam stopper spring 92 is an elastic body for the energizing cam stopper 87 to move up and down.

  The energizing cam stopper 87 includes a bar extending in the vertical direction and a bar extending in the horizontal direction intersecting the bar in the vertical direction. The bar extending in the horizontal direction protrudes to the outer peripheral side of the drive cam 8. The distal end portion of the bar extending in the horizontal direction is fitted into the energizing cam stopper cam groove 93 formed in the energizing cam stopper cam portion 88.

  When the drive cam 8 rotates, the bar extending in the horizontal direction of the energizing cam stopper 87 moves in the vertical direction so as to follow the energizing cam stopper cam groove 93. Therefore, the bar extending in the vertical direction of the energizing cam stopper 87 also moves in the vertical direction according to the energizing cam stopper cam groove 93.

  When the vertically extending rod of the energizing cam stopper 87 moves upward, the tip of the vertically extending rod is the bottom surface portion of the drive cam 8 so as to lock the relative rotation of the energizing cam body 90 with respect to the drive cam 8. Stick out from. As a result, the energization cam main body 90 is caught by the upper end portion of the energization cam stopper 87 and rotates while being fixed to the drive cam 8. When the vertically extending rod of the current-carrying cam stopper 87 moves downward, the current-carrying cam body 90 moves relative to the drive cam 8 until it sticks to the side wall of the cavity portion of the drive cam 8 in which it is stored. It rotates.

  Thus, the energization changeover switch SW3 rotates the energization cam body 90 relative to the drive cam 8 during the rotation of the drive cam 8 (in the middle of the tap changeover operation), thereby reversing the drive cam 8. Adjust the phase of the hour phase lead.

  With reference to FIG. 23, the structure of the VCB movable part which drives VCB3 is demonstrated.

  A VCB lifting / lowering holder 74 that covers the VCB lifting / lowering shaft 75 is attached to the VCB 3. The VCB elevating shaft 75 moves the electrode of the VCB 3 up and down. A drive pin 76 is attached to the VCB elevating holder 74. The pressurizing holder 72 and the pressurizing spring 73 apply a pressure for opening and closing the VCB 3 according to the vertical operation of the VCB lifting shaft 75. A VCB drive cam groove 77 into which the tip of the drive pin 76 fits is formed on the side surface of the drive cam 8. VCB drive cam groove 77 is formed so that VCB 3 opens and closes according to the sequence shown in FIG.

  The drive pin 76 operates according to the VCB drive cam groove 77. The VCB elevating shaft 75 operates following a drive pin 76 that operates as the drive cam 8 rotates. The VCB 3 opens and closes when the VCB elevating shaft 75 operates in the vertical direction.

  As shown in FIG. 17, the VCB 3 opening / closing operation has the same sequence in the switching operation from the A tap to the B tap and the switching operation from the B tap to the A tap. Therefore, the mechanism for opening / closing the VCB 3 is configured to be reversible between forward rotation and reverse rotation.

  According to the present embodiment, the electrical circuit of the on-load tap switching device 1 is configured by one, one VCB 3, one (one configuration) current limiting resistor 2, and three selector switches SW1, SW2, SW3. be able to.

  Further, according to the configuration of the electric circuit of the on-load tap switching device 1, the VCB 3 can cut off the load current IL and the circulating current IC at different timings. Generally, the current limiting resistance is set to a resistance value such that the load current and the circulating current are substantially the same. Therefore, the VCB 3 of the on-load tap switching device 1 only needs to cut about half the amount of current compared to the case where the combined current of the load current IL and the circulating current IC is cut off. Accordingly, the VCB 3 can be reduced in capacity or size.

  Further, the on-load tap switching device 1 is configured to switch the switching operation from the A tap to the B tap and the switching operation from the B tap to the A tap by switching between the normal rotation operation and the reversal operation by the energy storage mechanism 10. Has been. Thereby, the mutual switching operation | movement of A tap and B tap can be performed by simple control.

  In addition, since the changeover contact portions of all the changeover switches SW1 to SW3 are arranged on the outer peripheral side, the lead connection becomes easy and the number of parts can be reduced. As a result, the on-load tap switching device 1 can save space.

  Further, the energization cam main body 90 is moved relative to the drive cam 8 in the rotational direction of the energy storage mechanism 10 to adjust the phase when the energization changeover switch SW3 is rotated forward and reverse. By adopting such a configuration, the on-load tap switching device 1 can fit a mechanism for adjusting the phase at the time of forward rotation and inversion in a small space at the bottom of the on-load tap switching device 1.

  In addition, although some embodiment of this invention was described, these embodiment is shown as an example and is not intending limiting the range of invention. These novel embodiments can be implemented in various other forms, and various omissions, replacements, and changes can be made without departing from the scope of the invention. These embodiments and modifications thereof are included in the scope and gist of the invention, and are included in the invention described in the claims and the equivalents thereof.

  DESCRIPTION OF SYMBOLS 1 ... Tap change apparatus 1 at load, 1 ... Current limiting resistance, 3 ... VCB, SW1 ... Resistance change switch, SW2 ... VCB change switch, SW3 ... Energization change switch.

Claims (8)

A first contact connected to the first tap;
A second contact connected to the second tap ;
A first changeover switch that is electrically connected at one end to the first contact or the second contact and switches to the first contact or the second contact ;
A first common contact connected to the other end of the first changeover switch;
A third contact electrically connected to the first contact;
A fourth contact electrically connected to the second contact;
A resistor having one end connected to the first common contact;
A fifth contact connected to the other end of the resistor;
A second changeover switch that is electrically connected at one end to the third contact, the fourth contact, or the fifth contact to switch to the third contact, the fourth contact, or the fifth contact. When,
A second common contact connected to the other end of the second changeover switch;
A valve having one end connected to the second common contact;
A third common contact connected to the other end of the valve and connected to a location that serves as a reference potential for the first tap and the second tap;
A sixth contact electrically connected to the third contact;
A seventh contact electrically connected to the fourth contact;
An eighth contact electrically connected to the fifth contact;
The sixth contact, the seventh contact, or the eighth contact is electrically connected to one end to switch to the sixth contact, the seventh contact, or the eighth contact, and the other end is A third changeover switch connected to the third common contact ;
As a preliminary operation for switching from the second tap to the first tap, after the second changeover switch is changed to the fourth contact, the first changeover switch is changed to the second contact. Switch to
As a preliminary operation for switching from the first tap to the second tap, after the second changeover switch is changed to the third contact, the first changeover switch is changed to the first contact. An on- load tap switching device characterized by switching to   The on-load tap switching device according to claim 1, wherein the valve cuts off a load current and a circulating current due to a bridge between the taps at different timings. A rotational power source that generates power to rotate the shaft;
The first or second tap is switched from the first tap to the second tap when the shaft is rotated forward, and the second tap is switched to the first tap when the shaft is reversed. Item 3. The on-load tap switching device according to Item 2. First switching means for switching the first selector switch;
Second switching means for switching the second selector switch;
Third switching means for switching the third selector switch;
Valve opening and closing means for opening and closing the valve;
The on-load tap switching device according to claim 3, further comprising: a second switching unit, a third switching unit, and a driving unit that drives the valve opening / closing unit by the rotation of the shaft. First switching adjustment means for adjusting timing for switching the first changeover switch by the first switching means during forward rotation and reversal of the shaft;
5. The second switching adjustment means for adjusting a timing for switching the third changeover switch by the third switching means during forward rotation and reversal of the shaft. Tap changer when loaded.   6. The on-load tap switching device according to claim 5, wherein the second switching adjusting unit rotates the third switching unit relative to the shaft. A substrate having a contact pattern of each of the first changeover switch, the second changeover switch, and the third changeover switch;
7. The first change switch, the second change switch, and the third change switch include short-circuit means for short-circuiting the patterns of the substrate. The on-load tap switching device according to any one of the preceding claims. A control method for controlling the on-load tap switching device according to any one of claims 1 to 7,
The first selector switch selects the first contact, the second selector switch selects the third contact, the third selector switch selects the sixth contact, and the valve Is in a state where
Switching the third selector switch to the eighth contact;
After switching the third changeover switch to the eighth contact, the valve is opened,
After opening the valve, the second selector switch is switched to the fifth contact,
After switching the second changeover switch to the fifth contact, the valve is turned on,
After turning on the valve, the third selector switch is switched to the seventh contact,
A control method for a on-load tap switching device, comprising: opening the valve after switching the third selector switch to the seventh contact.

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