Description: A SWITCHGEAR
FIELD OF THE INVENTION
[0001] The present invention generally relates to a switchgear. In particular, the present invention relates to a disconnector assembly and a Vacuum Circuit Breaker (VCB) in a switchgear housing.
BACKGROUND OF THE INVENTION
[0002] In general, switchgears are employed for distribution of electric power in an electric distribution system. Usually, switchgears include a Vacuum Circuit Breaker (VCB) for medium and/or high voltages, e.g. 1-1000 kV, such as 12, 24 or 36 kV. Generally, switchgears are insulated by air, gas or oil. In a three-phase system, a gas-insulated switchgear includes one or more functional units in a gas filled compartment, each one comprising a grounded enclosure, three bushings connected to three external power cables (one for each phase), plurality of conductors arranged inside the enclosure and in one end connected to a respective bushing and in the opposite end connected to a respective switching devices. Each switching device is one of a manual switching device or an automated switching device. The switching devices can be connected in series to a bus bar. Each bus bar extends through all functional units comprised by the gas filled compartment.
[0003] In the existing switchgear designs, the bushings and, accordingly, the conductors connected thereto are arranged in parallel in a horizontal row configuration. This conventional switchgear design occupies more space and limits the number of switching device to not more than four in a single gas tank construction. Thus, the switchgear design is constrained in space to include more switching devices and optimize the available space inside the VCB.
[0004] In the light of the above, there is a need for a switchgear assembly that optimizes space inside the VCB to include more switching devices and reduce the overall size.
SUMMARY OF THE INVENTION
[0005] In an embodiment to the present invention a Vacuum Circuit Breaker (VCB) is disclosed. The VCB includes a vacuum interrupter arranged in a switchgear housing at a pre-defined angle from horizontal axis of the switchgear housing, the vacuum interrupter positioned in plane of rotation of a disconnector assembly and a feeder connection. The VCB also includes a toggle arrangement coupled to the vacuum interrupter at one end and to a main operating shaft at the other end in the plane of rotation of the vacuum interrupter, the toggle arrangement toggles a moving stem in the plane of movement of the vacuum interrupter between a first position and a second position, upon rotation of the main operating shaft, to connect and disconnect, respectively, the vacuum interrupter from a current flow path in the switchgear housing.
[0006] Further, the toggle arrangement includes a bell crank and yoke assembly, a tie rod assembly operationally linking the bell crank and yoke assembly to the moving stem and the vacuum interrupter and a contact loading spring, vertically mounted on the main operating shaft in the plane of movement of the vacuum interrupter, to couple the vacuum interrupter via the bell crank and yoke assembly to the main operating shaft. The toggle arrangement also includes an opening spring attached to a lever mounted on the main operating shaft to hold the vacuum interrupter in disconnected orientation.
[0007] Further, the bell crank and yoke assembly includes a bell crank arranged along a pole axis of the vacuum interrupter and a coupling yoke, arranged along the pole axis of the vacuum interrupter complementing the bell crank operationally attached to the bell crank.
[0008] Further, a spring end connector is arranged at a pre-defined angle with respect to the pole axis of the vacuum interrupter and connects the contact loading spring to the bell crank and yoke assembly.
[0009] Further, a flexible coupler is attached along the pole axis of the vacuum interrupter between the tie rod assembly and the vacuum interrupter. The flexible coupler enables coupling of a disconnector blade base with the vacuum interrupter such that the disconnector blade base is attached perpendicular to the pole axis of the vacuum interrupter.
[0010] Further, the contact loading spring is one of: a disc type spring and a coil type spring. Furthermore, the main operating shaft is a crank shaft.
[0011] Further, the moving stem is toggled in first position when the main operating shaft rotates in a counter clockwise direction under impact of rotation of an activating mechanism amounting to equivalent rotation of the lever attached to the main operating shaft, the opening spring stretches due to the rotation of the lever and potential energy is stored in the opening spring, the contact loading spring is compressed and the spring end connector move vertically down and the bell crank rotates in the counter clockwise direction due to vertical movement of the spring end connector. Further, the coupling yoke moves towards the vacuum interrupter along the pole axis of the vacuum interrupter due to the rotation of the bell crank, such that the tie rod assembly and the moving stem are pushed towards the vacuum interrupter along with the coupling yoke amounting to connection of the vacuum interrupter to the current flow path in the switchgear.
[0012] Further, the moving stem is toggled in second position when the main operating shaft rotates in a clockwise direction under impact of rotation of an activating mechanism amounting to equivalent rotation of the lever attached to the main operating shaft and the opening spring de-stretches due to the rotation of the lever and the potential energy released from the opening spring. The contact loading spring is de-compressed and the spring end connector move vertically up, the bell crank rotates in the clockwise direction due to vertical movement of the spring end connector and the coupling yoke moves away from the vacuum interrupter along the pole axis of the vacuum interrupter, due to the rotation of the bell crank, such that the tie rod assembly and the moving stem are pulled away from the vacuum interrupter along with the coupling yoke amounting to disconnection of the vacuum interrupter from the current flow path in the switchgear.
[0013] Further, the VCB forms a part of a switchgear housing, the switchgear housing further comprises a disconnector assembly. An embodiment of the present invention discloses a switchgear housing having a disconnector assembly and a Vacuum Circuit Breaker (VCB). The VCB includes a vacuum interrupter arranged in a switchgear housing at a pre-defined angle from horizontal axis of the switchgear housing, the vacuum interrupter positioned in plane of rotation of a disconnector assembly and a feeder connection. The VCB also includes a toggle arrangement coupled to the vacuum interrupter at one end and to a main operating shaft at the other end in the plane of rotation of the vacuum interrupter, the toggle arrangement toggles a moving stem in the plane of movement of the vacuum interrupter between a first position and a second position, upon rotation of the main operating shaft, to connect and disconnect, respectively, the vacuum interrupter from a current flow path in the switchgear housing.
[0014] Further, the toggle arrangement includes a bell crank and yoke assembly, a tie rod assembly operationally linking the bell crank and yoke assembly to the moving stem and the vacuum interrupter and a contact loading spring, vertically mounted on the main operating shaft in the plane of movement of the vacuum interrupter, to couple the vacuum interrupter via the bell crank and yoke assembly to the main operating shaft. The toggle arrangement also includes an opening spring attached to a lever mounted on the main operating shaft to hold the vacuum interrupter in disconnected orientation.
[0015] Further, the bell crank and yoke assembly includes a bell crank arranged along a pole axis of the vacuum interrupter and a coupling yoke, arranged along the pole axis of the vacuum interrupter complementing the bell crank operationally attached to the bell crank.
[0016] Further, a spring end connector is arranged at a pre-defined angle with respect to the pole axis of the vacuum interrupter and connects the contact loading spring to the bell crank and yoke assembly.
[0017] Further, a flexible coupler is attached along the pole axis of the vacuum interrupter between the tie rod assembly and the vacuum interrupter. The flexible coupler enables coupling of a disconnector blade base with the vacuum interrupter such that the disconnector blade base is attached perpendicular to the pole axis of the vacuum interrupter.
[0018] Further, the contact loading spring is one of: a disc type spring and a coil type spring. Furthermore, the main operating shaft is a crank shaft.
[0019] Further, the moving stem is toggled in first position when the main operating shaft rotates in a counter clockwise direction under impact of rotation of an activating mechanism amounting to equivalent rotation of the lever attached to the main operating shaft, the opening spring stretches due to the rotation of the lever and potential energy is stored in the opening spring, the contact loading spring is compressed and the spring end connector move vertically down and the bell crank rotates in the counter clockwise direction due to vertical movement of the spring end connector. Further, the coupling yoke moves towards the vacuum interrupter along the pole axis of the vacuum interrupter due to the rotation of the bell crank, such that the tie rod assembly and the moving stem are pushed towards the vacuum interrupter along with the coupling yoke amounting to connection of the vacuum interrupter to the current flow path in the switchgear.
[0020] Further, the moving stem is toggled in second position when the main operating shaft rotates in a clockwise direction under impact of rotation of an activating mechanism amounting to equivalent rotation of the lever attached to the main operating shaft and the opening spring de-stretches due to the rotation of the lever and the potential energy released from the opening spring. The contact loading spring is de-compressed and the spring end connector move vertically up, the bell crank rotates in the clockwise direction due to vertical movement of the spring end connector and the coupling yoke moves away from the vacuum interrupter along the pole axis of the vacuum interrupter, due to the rotation of the bell crank, such that the tie rod assembly and the moving stem are pulled away from the vacuum interrupter along with the coupling yoke amounting to disconnection of the vacuum interrupter from the current flow path in the switchgear.
[0021] Further, the disconnector assembly includes a drive mechanism, a disconnector shaft, a disconnector lever, a disconnector link and moving contact. Furthermore, one end of the moving contact is attached to the disconnector link and other end is attached to the disconnector blade base of the vacuum interrupter.
[0022] Further, upon contact of the moving contact with a main access point due to actuation by the drive mechanism in clockwise direction and the connection of the vacuum interrupter with the current flow path of the housing due to actuation by the toggle arrangement, the switchgear enables connection of power supply to load.
[0023] Further, upon contact of the moving contact with an earth feeder point due to actuation by the drive mechanism in counter clockwise direction and the connection of the vacuum interrupter with the current flow path of the housing due to actuation by the toggle arrangement, the switchgear disconnects power supply to the load and passes the power to earth feeder point.
[0024] Further, upon contact of the moving contact with a neutral point due to actuation by the drive mechanism in one of: clockwise direction from the earth feeder point and the counter clockwise direction from the main access point and the disconnection of the vacuum interrupter from the current flow path of the housing due to actuation by the toggle arrangement, the switchgear disconnects power supply from load.
BRIEF DESCRIPTION OF DRAWINGS
[0025] The following drawings are illustrative of preferred embodiments for enabling the present invention and are not intended to limit the scope of the invention. The drawings are not to scale (unless so stated) and are intended for use in conjunction with the explanations in the following detailed description.
[0026] Figure 1 illustrates a schematics of a switchgear in accordance with an embodiment of the present invention;
[0027] Figure 2 illustrates a sectional view of a disconnector assembly and a Vacuum Circuit Breaker (VCB) in the switchgear in accordance with an embodiment of the present invention;
[0028] Figure 3 illustrates a front view of the VCB in accordance with an embodiment of the present invention;
[0029] Figure 4 illustrates an exploded view of the VCB in accordance with an embodiment of the present invention;
[0030] Figure 5 illustrates another exploded view of the VCB in accordance with an embodiment of the present invention; and
[0031] Figure 6 illustrates the switchgear in a main operating state of the switchgear in accordance with an embodiment of the present invention;
[0032] Figure 7 illustrates the switchgear in an earth operating state of the switchgear in accordance with an embodiment of the present invention; and
[0033] Figure 8 illustrates the switchgear in OFF operating state of the switchgear in accordance with an embodiment of the present invention.
DETAILED DESCRIPTION OF DRAWINGS
[0034] The following disclosure is provided in order to enable a person having ordinary skill in the art to practice the invention. Exemplary embodiments are provided only for illustrative purposes and various modifications will be readily apparent to persons skilled in the art. The general principles defined herein may be applied to other embodiments and applications without departing from the spirit and scope of the invention. Also, the terminology and phraseology used is for the purpose of describing exemplary embodiments and should not be considered limiting. Thus, the present invention is to be accorded the widest scope encompassing numerous alternatives, modifications and equivalents consistent with the principles and features disclosed. For the purpose of clarity, details relating to technical material that is known in the technical fields related to the invention have not been described in detail so as not to unnecessarily obscure the present invention.
[0035] Figure 1 illustrates a schematics of a switchgear in accordance with an embodiment of the present invention. Further, figure 2 illustrates a sectional view of a disconnector assembly 118 and a Vacuum Circuit Breaker (VCB) 100 in the switchgear in accordance with an embodiment of the present invention. For the sake of brevity figures 1 and 2 have been described together.
[0036] In an embodiment of the present invention, a switchgear may reside in a hermetically sealed gas tight enclosure fabricated to hold insulation gas. In an embodiment of the present invention, the insulation gas filled inside the switchgear housing 124 may be Sulfur Hexafluoride (SF6). It may be understood that the switchgear may provide a current flow path from source of power to load. The loads may, without any limitation, be electrical devices. In an embodiment of the present invention, the switchgear housing 124 may include a main access point 112, an earth feeder point 114 and a neutral point. The main access point 112 and the earth feeder point 114 may be separated by a pre-defined distance. Further, the neutral point may be understood as a position between the main access point 112 and the earth feeder point 114 inside the switchgear housing 124. The switchgear may have a main operating state, an earth operating state and an OFF operating state. In the main operating state, the load is connected to main power source via the main access point 112. Further, in earth operating state the main power source is connected to earth feeder point 114, to earth surplus power in the current flow path. Furthermore, in the OFF operating state the main power is disconnected from the current flow path and placed in the neutral point.
[0037] In an embodiment of the present invention, the switchgear housing 124 may house a disconnector assembly 118, a Vacuum Circuit Breaker (VCB) 100 and feeder mechanism 126. The disconnector assembly 118 may be a manually operated switching device and the VCB 100 may be either a manually operated switching device or an automatic switching device. The disconnector assembly 118 and the VCB 100 may together open or close current flow path of the feeder mechanism 126 for the supply of power to load. The details of orientations of the disconnector assembly 118 and the VCB 100 in different operating states of the switchgear have been elaborated in subsequent paragraphs. Further, the current from the power source may pass into the VCB 100 and the disconnector assembly 118 via a feeder connection 106 of the feeder mechanism 126. The feeder mechanism 126 may be provided with three main bushings 128, each one for an electric input phase. Furthermore, a main bus bar 116 may be coupled to the disconnector assembly 118 for transferring the current received from the feeder mechanism 126 to an electrical apparatus.
[0038] The VCB 100 may include a vacuum interrupter 104 and a toggle arrangement 110. The vacuum interrupter 104 may be housed in an insulated enclosure with a moving stem and fixed stem. The vacuum interrupter 104 may be arranged in the switchgear housing 124 at a pre-defined angle from horizontal axis 130 of the switchgear housing 124. In an exemplary embodiment of the present invention, the pre-defined angle may be within the range of 30 to 45 degrees. In an embodiment of the present invention, the fixed stem of the vacuum interrupter 104 may be attached to the feeder mechanism 126 and the moving stem may be attached to the toggle arrangement 110. In an exemplary embodiment of the present invention, the vacuum interrupter 104 may be positioned in the plane of rotation of the disconnector assembly 118 and the feeder mechanism 126. The vacuum interrupter 104 and the disconnector assembly 118 are mounted on the common mounting point to provide structural rigidity and reduce vibration during operation.
[0039] Further, the toggle arrangement 110 may be coupled to the vacuum interrupter 104 via the moving stem at one end and to a main operating shaft 208 at the other end in the plane of movement of the vacuum interrupter 104. In an embodiment of the present invention, the toggle arrangement 110 may toggle the moving stem in the plane of movement of the vacuum interrupter 104 between a first position and a second position. The toggling of the moving stem may be upon rotation of the main operating shaft 208. Further, in the first position of the moving stem the vacuum interrupter 104 may be connected to the current flow path in the switchgear housing 124. Also, in the second position of the moving stem the vacuum interrupter 104 may be disconnected from the current flow path in the switchgear housing 124. The details of toggling of the moving stem in the different positions and the connection or disconnection of the vacuum interrupter 104 from the current flow path have been elaborated in subsequent paragraphs.
[0040] In an embodiment of the present invention, the disconnector assembly 118 may include a disconnector shaft 210, a disconnector lever 212, a disconnector link 214 and a moving contact 120. The disconnector shaft 210 and the disconnector lever 212 may be attached to a drive mechanism of the disconnector assembly 118. The actuation of the disconnector shaft 210 and the disconnector lever 212 under the impact of the drive mechanism may amount to actuation of the disconnector link 214 and the moving contact 120 to toggle the switchgear between the different operating states. The details of toggling of the switchgear in the different operating states due to the actuation of the moving contact 120 under the impact of the drive mechanism have been elaborated in subsequent paragraphs.
[0041] In an exemplary embodiment of the present invention, plurality of grooves may be provided in the switchgear housing 124 around the VCB 100, such that the gas in the switchgear housing 124 may circulate around the vacuum interrupter 104 to cool the vacuum interrupter 104. Further, the arrangement of the vacuum interrupter 104 at the pre-defined angle with respect to the horizontal axis 130 of the switchgear housing 124 may include surface of area of contact of the gas with the vacuum interrupter 104 to facilitate a faster and efficient cooling.
[0042] Figure 3 illustrates a front view of the VCB 100 in accordance with an embodiment of the present invention. Further, figure 4 illustrates an exploded view of the VCB 100 in accordance with an embodiment of the present invention. Furthermore, figure 5 illustrates another exploded view of the VCB 100 in accordance with an embodiment of the present invention. For the sake of brevity figures 3, 4 and 5 have been described together.
[0043] In the VCB 100 the vacuum interrupter 104 may be coupled to the toggle arrangement 110 to connect or disconnect the vacuum interrupter 104 with the current flow path. The toggle arrangement 110 may include a bell crank and yoke assembly 304, a tie rod assembly 202, a contact loading spring 206, a spring end connector 402 and an opening spring 122. In an exemplary embodiment of the present invention, the contact loading spring 206 may be a disc type spring or a coil type spring.
[0044] In an embodiment of the present invention, the tie rod assembly 202 may operationally link the bell crank and yoke assembly 304 to the moving stem and the vacuum interrupter 104. Further, the contact loading spring 206 may be vertically mounted on the main operating shaft 208 in the plane of movement of the vacuum interrupter 104. In an exemplary embodiment of the present invention, the main operating shaft 208 may be a crank shaft. The contact loading spring 206 may couple the vacuum interrupter 104 via the bell crank and yoke assembly 304 to the main operating shaft 208. Additionally, the opening spring 122 may be attached to a lever 308 mounted on the main operating shaft 208 to hold the vacuum interrupter 104 in disconnected orientation.
[0045] Further, the bell crank and yoke assembly 304 may include a bell crank 204 arranged along a pole axis 502 of the vacuum interrupter 104 and a coupling yoke 306. The coupling yoke 306 may be arranged along the pole axis 502 of the vacuum interrupter 104 complementing the bell crank 204 operationally attached to the bell crank 204. Additionally, the spring end connector 402 may be arranged at a pre-defined angle with respect to the pole axis 502 of the vacuum interrupter 104 and may connect the contact loading spring 206 to the bell crank and yoke assembly 304.
[0046] In an exemplary embodiment of the present invention, the VCB 100 may have a flexible coupler 302. The flexible coupler 302 may be made of a conducting material. In exemplary embodiments of the present invention, the conducting material may be, without any limitation, copper, aluminium, silver or an alloy thereof. Further, the flexible coupler 302 may be attached along the pole axis 502 of the vacuum interrupter 104 between the tie rod assembly 202 and the vacuum interrupter 104. The flexible coupler 302 may enable coupling of a disconnector blade base 108 with the vacuum interrupter 104, such that the disconnector blade base 108 is attached perpendicular to the pole axis 502 of the vacuum interrupter 104. In an embodiment of the present invention, a dielectric shield may be mounted on the flexible coupler 302 to enable desired passage of the current to the disconnector assembly 118 via the flexible coupler 302 and the disconnector blade base 108.
[0047] In an exemplary embodiment of the present invention, the moving stem 508 may be toggled by the toggle arrangement 110 in the first position to close the connection between the vacuum interrupter 104 and the disconnector blade base 108 and to enable passage of current to the disconnector assembly 118. Further, the moving stem 508 may be toggled in the first position when the main operating shaft 208 may rotate in a counter clockwise direction under impact of rotation of an activating mechanism amounting to equivalent rotation of the lever 308 attached to the main operating shaft 208. The activating mechanism may be understood as a drive mechanism for triggering the actuation of the toggle arrangement 110. Next, the opening spring 122 may stretch due to the rotation of the lever 308 and potential energy may be stored in the opening spring 122. Further, the contact loading spring 206 may be compressed and the spring end connector 402 may move vertically down. The bell crank 204 may rotate in the counter clockwise direction due to vertical movement of the spring end connector 402 and the coupling yoke 306 may move towards the vacuum interrupter 104 along the pole axis 502 of the vacuum interrupter 104 due to the rotation of the bell crank 204. The movement of the coupling yoke 306 may amount to the tie rod assembly 202 and the moving stem 508 being pushed towards the vacuum interrupter 104 to connect the vacuum interrupter 104 to the current flow path in the switchgear.
[0048] In an embodiment of the present invention, the moving stem 508 may be toggled by the toggle arrangement 110 in the second position to open the connection between the vacuum interrupter 104 and the disconnector blade base 108 and to disenable passage of current to the disconnector assembly 118. The moving stem 508 may be toggled in second position when the main operating shaft 208 may rotate in a clockwise direction under impact of rotation of the activating mechanism amounting to equivalent rotation of the lever 308 attached to the main operating shaft 208. Further, the opening spring 122 may de-stretch due to the rotation of the lever 308 and the potential energy may be released from the opening spring 122. The contact loading spring 206 may be de-compressed and the spring end connector 402 may move vertically up. Further, the bell crank 204 may rotate in the clockwise direction due to vertical movement of the spring end connector 402 and the coupling yoke 306 may move away from the vacuum interrupter 104 along the pole axis 502 of the vacuum interrupter 104, due to the rotation of the bell crank 204. Further, the tie rod assembly 202 and the moving stem 508 may be pulled away from the vacuum interrupter 104 along with the coupling yoke 306 amounting to disconnection of the vacuum interrupter 104 from the current flow path in the switchgear.
[0049] In an exemplary embodiment of the present invention, a coupler bracket 312 may be provided to pivot the toggle arrangement 110. Further, through grooves in the coupler bracket 312 may enable flow of the insulating gas for cooling of the vacuum interrupter 104 heated due to passage of current. In an embodiment of the present invention, the coupler bracket 312 may be coupled with the bell crank and yoke assembly 304 via a plurality of connecting pins.
[0050] Figure 6 illustrates the switchgear in the main operating state in accordance with an embodiment of the present invention. In an exemplary embodiment of the present invention, the switchgear may transition to the main operating state from the OFF operating state or earth operating state. Further, for the switchgear to be oriented in the main operating state the disconnector shaft 210 may rotate in clockwise direction by a pre-defined angle, amounting to movement of the disconnector lever 212 from left to right. The movement of the disconnector lever 212 towards right, may pull the disconnector link 214 to the right and which in turn may pivot a first end 602 of the moving contact 120 to the right and connect the first end 602 of the moving contact 120 with the main access point 112. It may be understood that the direction of rotation of the disconnector shaft 210, direction of the movement of the disconnector lever 212 and the direction of pivoting of the moving contact 120 have been mentioned with respect to the position of the main access point 112, the earth feeder point 114 and the neutral point in accordance with an embodiment of the present invention and may vary based on variation in the position of the main access point 112, the earth feeder point 114 and the neutral point.
[0051] Further, a second end 604 of the moving contact 120 may be coupled to the disconnector blade base 108. Furthermore, the moving stem 508 of the vacuum interrupter 104 may be oriented in the first position by the toggle arrangement 110 to connect the vacuum interrupter 104 to the current flow path. As a result of the connection of the vacuum interrupter 104 to the current flow path, the current may flow to the disconnector blade base 108 from via the flexible coupler 302 and from the disconnector blade base 108 to the moving contact 120. Thus, current is allowed to pass from the source of power to the load as both the disconnector assembly 118 and the vacuum interrupter 104 are connected to current flow path and are switched on.
[0052] Figure 7 illustrates the switchgear in the earth operating state in accordance with an embodiment of the present invention. In an exemplary embodiment of the present invention, the switchgear may transition to the earth operating state from the OFF operating state or main operating state. Further, for the switchgear to be oriented in the earth operating state the disconnector shaft 210 may rotate in counter clockwise direction by a pre-defined angle, amounting to movement of the disconnector lever 212 from right to left. The movement of the disconnector lever 212 towards left, may push the disconnector link 214 to the left and which in turn may pivot the first end 602 of the moving contact 120 to the left and connect the first end 602 of the moving contact 120 with the earth feeder point 114. It may be understood that the direction of rotation of the disconnector shaft 210, direction of the movement of the disconnector lever 212 and the direction of pivoting of the moving contact 120 have been mentioned with respect to the position of the main access point 112, the earth feeder point 114 and the neutral point in accordance with an embodiment of the present invention and may be vary based on variation in the position of the main access point 112, the earth feeder point 114 and the neutral point.
[0053] Further, the second end 604 of the moving contact 120 may be coupled to the disconnector blade base 108. Furthermore, the moving stem 508 of the vacuum interrupter 104 may be oriented in the first position by the toggle arrangement 110 to connect the vacuum interrupter 104 to the current flow path. As a result of the connection of the vacuum interrupter 104 to the current flow path, the current may flow to the disconnector blade base 108 from via the flexible coupler 302 and from the disconnector blade base 108 to the moving contact 120. Thus, current is allowed to pass from the source of power to the earth feeder point 114 as both the disconnector assembly 118 and the vacuum interrupter 104 are connected to current flow path and are switched on.
[0054] Figure 8 illustrates the switchgear in OFF operating state in accordance with an embodiment of the present invention. In the OFF operating state of the switchgear the moving contact 120 of the disconnector assembly 118 may be positioned at the neutral point, such that the current flow path from the vacuum interrupter 104 to the load via disconnector assembly 118 is in open to prohibit flow of the current. Further, the moving stem 508 of the vacuum interrupter 104 may be oriented in the second position, such that the vacuum interrupter 104 is disconnected from the current flow path. Thus, current is restricted and not allowed to pass from the source of power to the load as both the disconnector assembly 118 and the vacuum interrupter 104 are disconnected from current flow path and are switched off.
[0055] In an exemplary embodiment of the present invention, to orient the switchgear in the OFF operating state from the main operating state, the disconnector shaft 210 may rotate in counter clockwise direction, amounting to the movement of the disconnector lever 212 and the disconnector link 214 to the left. The moving contact 120 may pivot to the left and rest at the neutral point. It may be understood that the direction of rotation of the disconnector shaft 210, direction of the movement of the disconnector lever 212 and the direction of pivoting of the moving contact 120 have been mentioned with respect to the position of the main access point 112, the earth feeder point 114 and the neutral point in accordance with an embodiment of the present invention and may be vary based on variation in the position of the main access point 112, the earth feeder point 114 and the neutral point.
[0056] In an exemplary embodiment of the present invention, to orient the switchgear in the OFF operating state from the earth operating state, the disconnector shaft 210 may rotate in clockwise direction, amounting to the movement of the disconnector lever 212 and the disconnector link 214 to the right. The moving contact 120 may pivot to the right and rest at the neutral point. It may be understood that the direction of rotation of the disconnector shaft 210, direction of the movement of the disconnector lever 212 and the direction of pivoting of the moving contact 120 have been mentioned with respect to the position of the main access point 112, the earth feeder point 114 and the neutral point in accordance with an embodiment of the present invention and may be vary based on variation in the position of the main access point 112, the earth feeder point 114 and the neutral point.
[0057] Accordingly, the present invention provides the following effects or advantages. The present invention discloses a switching assembly for the VCB 100 to toggle between different operating states. The switching assembly is positioned in a low-profile manner inside the VCB 100 i.e., in an inclined orientation. This type of orientation of the switching assembly enables to positioned coplanar with other components inside the VCB 100 such as the disconnector assembly 118 and the feeder mechanism 126. Further, the design of the switching assembly allows to position all the components in the same plane as of the housing 124 of the VCB 100.
[0058] Further, the switching assembly design, architecture, and assembly conditions optimizes the available space inside the VCB 100. The optimized space allows for housing 124 increased number of switching devices inside the gas tight enclosure of the VCB 100. Further, the present invention provides a unique constructional aspect in the assembly members of the switching assembly to keep the simplicity and symmetricity of the arrangements of the mechanical and contact members.
[0059] While the exemplary embodiments of the present invention are described and illustrated herein, it will be appreciated that they are merely illustrative. It will be understood by those skilled in the art that various modifications in form and detail may be made therein without departing from or offending the spirit and scope of the invention as defined by the appended claims. , Claims: I/We claim:
1. A Vacuum Circuit Breaker (VCB) (100) comprising:
a vacuum interrupter (104) arranged in a switchgear housing (124) at a pre-defined angle from horizontal axis (130) of the switchgear housing (124), the vacuum interrupter (104) positioned in plane of rotation of a disconnector assembly (118) and a feeder mechanism (126); and
a toggle arrangement (110) coupled to the vacuum interrupter (104) at one end and to a main operating shaft (208) at the other end in the plane of rotation of the vacuum interrupter (104), the toggle arrangement (110) toggles a moving stem (508) in the plane of movement of the vacuum interrupter (104) between a first position and a second position, upon rotation of the main operating shaft (208), to connect and disconnect, respectively, the vacuum interrupter (104) from a current flow path in the switchgear housing (124).
2. The VCB (100) as claimed in claim 1, wherein the toggle arrangement (110) includes:
a bell crank and yoke assembly (304);
a tie rod assembly (202) operationally linking the bell crank and yoke assembly (304) to the moving stem (508) and the vacuum interrupter (104);
a contact loading spring (206), vertically mounted on the main operating shaft (208) in the plane of movement of the vacuum interrupter (104), to couple the vacuum interrupter (104) via the bell crank and yoke assembly (304) to the main operating shaft (208); and
an opening spring (122) attached to a lever (308) mounted on the main operating shaft (208) to hold the vacuum interrupter (104) in disconnected orientation.
3. The VCB (100) as claimed in claim 2, wherein the bell crank and yoke assembly (304) includes:
a bell crank (204) arranged along a pole axis (502) of the vacuum interrupter (104); and
a coupling yoke (306), arranged along the pole axis (502) of the vacuum interrupter (104) complementing the bell crank (204) operationally attached to the bell crank (204).
4. The VCB (100) as claimed in claim 2, wherein a spring end connector (402) is arranged at a pre-defined angle with respect to the pole axis (502) of the vacuum interrupter (104) and connects the contact loading spring (206) to the bell crank and yoke assembly (304).
5. The VCB (100) as claimed in claim 2, wherein a flexible coupler (302) is attached along the pole axis (502) of the vacuum interrupter (104) between the tie rod assembly (202) and the vacuum interrupter (104), the flexible coupler (302) enables coupling of a disconnector blade base (108) with the vacuum interrupter (104) such that the disconnector blade base (108) is attached perpendicular to the pole axis (502) of the vacuum interrupter (104).
6. The VCB (100) as claimed in claim 2, wherein the contact loading spring (206) is one of: a disc type spring and a coil type spring.
7. The VCB (100) as claimed in claim 1, wherein the main operating shaft (208) is a crank shaft.
8. The VCB (100) as claimed in one of claims 1-7, wherein the moving stem (508) is toggled in first position when:
the main operating shaft (208) rotates in a counter clockwise direction under impact of rotation of an activating mechanism amounting to equivalent rotation of the lever (308) attached to the main operating shaft (208);
the opening spring (122) stretches due to the rotation of the lever (308) and potential energy is stored in the opening spring (122);
the contact loading spring (206) is compressed and the spring end connector (402) move vertically down;
the bell crank (204) rotates in the counter clockwise direction due to vertical movement of the spring end connector (402);
the coupling yoke (306) moves towards the vacuum interrupter (104) along the pole axis (502) of the vacuum interrupter (104) due to the rotation of the bell crank (204), such that the tie rod assembly (202) and the moving stem (508) are pushed towards the vacuum interrupter (104) along with the coupling yoke (306) amounting to connection of the vacuum interrupter (104) to the current flow path in the switchgear.
9. The VCB (100) as claimed in claim 8, wherein the moving stem (508) is toggled in second position when:
the main operating shaft (208) rotates in a clockwise direction under impact of rotation of an activating mechanism amounting to equivalent rotation of the lever (308) attached to the main operating shaft (208);
the opening spring (122) de-stretches due to the rotation of the lever (308) and the potential energy released from the opening spring (122);
the contact loading spring (206) is de-compressed and the spring end connector (402) move vertically up;
the bell crank (204) rotates in the clockwise direction due to vertical movement of the spring end connector (402);
the coupling yoke (306) moves away from the vacuum interrupter (104) along the pole axis (502) of the vacuum interrupter (104), due to the rotation of the bell crank (204), such that the tie rod assembly (202) and the moving stem (508) are pulled away from the vacuum interrupter (104) along with the coupling yoke (306) amounting to disconnection of the vacuum interrupter (104) from the current flow path in the switchgear.
10. The VCB (100) as claimed in one of claims 1-9, forms a part of a switchgear housing (124), the switchgear housing (124) further comprises a disconnector assembly (118).
11. A switchgear housing (124) comprising:
a disconnector assembly (118);
a Vacuum Circuit Breaker (VCB) (100), the VCB (100) comprising:
a vacuum interrupter (104) arranged in the switchgear housing (124) at a pre-defined angle from horizontal axis (130) of the switchgear housing (124), the vacuum interrupter (104) positioned in plane of rotation of a disconnector assembly (118) and a feeder mechainsm (126); and
a toggle arrangement (110) coupled to the vacuum interrupter (104) at one end and to a main operating shaft (208) at the other end in the plane of rotation of the vacuum interrupter (104), the toggle arrangement (110) toggles a moving stem (508) in the plane of movement of the vacuum interrupter (104) between a first position and a second position, upon rotation of the main operating shaft (208), to connect and disconnect, respectively, the vacuum interrupter (104) from a current flow path in the switchgear housing (124).
12. The switchgear housing (124) as claimed in claim 11, wherein the toggle arrangement (110) includes:
a bell crank and yoke assembly (304);
a tie rod assembly (202) operationally linking the bell crank and yoke assembly (304) to the moving stem (508) and the vacuum interrupter (104);
a contact loading spring (206), vertically mounted on the main operating shaft (208) in the plane of movement of the vacuum interrupter (104), to couple the vacuum interrupter (104) via the bell crank and yoke assembly (304) to the main operating shaft (208); and
an opening spring (122) attached to a lever (308) mounted on the main operating shaft (208) to hold the vacuum interrupter (104) in disconnected orientation.
13. The switchgear housing (124) as claimed in claim 12, wherein the bell crank and yoke assembly (304) includes:
a bell crank (204) arranged along a pole axis (502) of the vacuum interrupter (104); and
a coupling yoke (306), arranged along the pole axis (502) of the vacuum interrupter (104) complementing the bell crank (204) operationally attached to the bell crank (204).
14. The switchgear housing (124) as claimed in claim 12, wherein a spring end connector (402) is arranged at a pre-defined angle with respect to the pole axis (502) of the vacuum interrupter (104) and connects the contact loading spring (206) to the bell crank and yoke assembly (304).
15. The switchgear housing (124) as claimed in claim 12, wherein a flexible coupler (302) is attached along the pole axis (502) of the vacuum interrupter (104) between the tie rod assembly (202) and the vacuum interrupter (104), the flexible coupler (302) enables coupling of a disconnector blade base (108) with the vacuum interrupter (104) such that the disconnector blade base (108) is attached perpendicular to the pole axis (502) of the vacuum interrupter (104).
16. The switchgear housing (124) as claimed in claim 12, wherein the contact loading spring (206) is one of: a disc type spring and a coil type spring.
17. The switchgear housing (124) as claimed in claim 11, wherein the main operating shaft (208) is a crank shaft.
18. The switchgear housing (124) as claimed in one of claims 11-17, wherein the moving stem (508) is toggled in first position when:
the main operating shaft (208) rotates in a counter clockwise direction under impact of rotation of an activating mechanism amounting to equivalent rotation of the lever (308) attached to the main operating shaft (208);
the opening spring (122) stretches due to the rotation of the lever (308) and potential energy is stored in the opening spring (122);
the contact loading spring (206) is compressed and the spring end connector (402) move vertically down;
the bell crank (204) rotates in the counter clockwise direction due to vertical movement of the spring end connector (402);
the coupling yoke (306) moves towards the vacuum interrupter (104) along the pole axis (502) of the vacuum interrupter (104) due to the rotation of the bell crank (204), such that the tie rod assembly (202) and the moving stem (508) are pushed towards the vacuum interrupter (104) along with the coupling yoke (306) amounting to connection of the vacuum interrupter (104) to the current flow path in the switchgear.
19. The switchgear housing (124) as claimed in claim 18, wherein the moving stem (508) is toggled in second position when:
the main operating shaft (208) rotates in a clockwise direction under impact of rotation of an activating mechanism amounting to equivalent rotation of the lever (308) attached to the main operating shaft (208);
the opening spring (122) de-stretches due to the rotation of the lever (308) and the potential energy released from the opening spring (122);
the contact loading spring (206) is de-compressed and the spring end connector (402) move vertically up;
the bell crank (204) rotates in the clockwise direction due to vertical movement of the spring end connector (402);
the coupling yoke (306) moves away from the vacuum interrupter (104) along the pole axis (502) of the vacuum interrupter (104), due to the rotation of the bell crank (204), such that the tie rod assembly (202) and the moving stem (508) are pulled away from the vacuum interrupter (104) along with the coupling yoke (306) amounting to disconnection of the vacuum interrupter (104) from the current flow path in the switchgear.
20. The switchgear housing (124) as claimed in claim 11, wherein the disconnector assembly (118) includes a drive mechanism, a disconnector shaft (210), a disconnector lever (212), a disconnector link (214) and moving contact (120).
21. The switchgear housing (124) as claimed in one of claims 15 and 20, wherein one end of the moving contact (120) is attached to the disconnector link (214) and other end is attached to the disconnector blade base (108) of the vacuum interrupter (104).
22. The switchgear housing (124) as claimed in claim 21, wherein upon contact of the moving contact (120) with a main access point 112 due to actuation by the drive mechanism in clockwise direction and the connection of the vacuum interrupter (104) with the current flow path of the housing (124) due to actuation by the toggle arrangement (110), the switchgear enables connection of power supply to load.
23. The switchgear housing (124) as claimed in claim 21, wherein upon contact of the moving contact (120) with an earth feeder point (114) due to actuation by the drive mechanism in counter clockwise direction and the connection of the vacuum interrupter (104) with the current flow path of the housing (124) due to actuation by the toggle arrangement (110), the switchgear disconnects power supply to the load and passes the power to earth feeder point (114).
24. The switchgear housing (124) as claimed in claim 21, wherein upon contact of the moving contact (120) with a neutral point due to actuation by the drive mechanism in one of: clockwise direction from the earth feeder point (114) and the counter clockwise direction from the main access point (112) and the disconnection of the vacuum interrupter (104) from the current flow path of the housing (124) due to actuation by the toggle arrangement (110), the switchgear disconnects power supply from load.