Split-phase phase control type inrush current suppression equipment and method

Abstract

The invention relates to split-phase phase control type inrush current suppression equipment and method for a power distribution network circuit device. The equipment comprises quick switches which are respectively connected in series in each phase line. In each phase line, the fast switch arranged on one phase line and the fast switches arranged on any other phase line except the phase line can share one set of closing energy supply device, and the closing energy supply device is internally provided with a pull-in branch; and the quick switches which are served by the switching-on energy supply device and need to be switched off synchronously share one switching-off energy supply device. According to the utility model, independent switching-on and switching-off energy supply devices respectively equipped for some fast switches in the existing equipment are integrated into one set of switching-on and switching-off energy supply device which can be commonly used by the fast switches, at least one set of switching-on and switching-off energy supply device is saved, and the equipment cost is saved. The pull-in branch avoids the situation that the equipment cannot effectively suppress the closing inrush current due to the wrong closing sequence of the two high-speed switches.

Description

Technical Field

[0001] The invention relates to a distribution network circuit device, in particular to a phase-splitting phase-controlled inrush current suppression device and method for switching capacitor groups in the distribution network. Background Art

[0002] In the power distribution network, in order to compensate for the capacitive charging current of the line, maintain the system voltage and ensure the reliable operation of the line, a parallel capacitor bank is generally used to solve the problem. However, at the moment of closing the capacitor bank, a closing surge current will be generated to impact the capacitor bank, and the larger the capacity of the capacitor bank, the greater the closing surge current will be.

[0003] In order to control the inrush current and overvoltage generated when switching on and off the reactive power compensation capacitor bank in the distribution network system, an inrush current suppression device can be installed in the reactive power compensation line on the incoming line side of the capacitor bank to control the switching of the capacitor bank and suppress the inrush current and overvoltage generated during the switching process.

[0004] Among them, according to the principle that the inrush current generated by the three phases of the feeder switch are opened and closed at the zero-crossing point of the phase angle, in order to make the switch in the inrush current suppression device to reduce the inrush current generated by the capacitor bank switching, the switch is usually selected to have a fast closing and opening speed. For example, the eddy current driven direct-acting fast circuit breaker, this type of fast switch can complete the closing and opening action within a microsecond response time.

[0005] In practical applications, the mechanism for driving the closing and opening actions of the eddy current driven direct-acting fast circuit breaker includes a pair of coil disks (one for closing, which is the closing coil disk; the other for opening, which is the opening coil disk; the lower pull rod can pass through the middle of the coil disk, and the coil disk is fixed in the sealed pole) and an eddy current disk (located between the two coil disks and fixed on the rod body of the lower pull rod, and can move synchronously with the lower pull rod). Each coil disk is also equipped with a set of energy supply devices that can provide electrical energy to the coil disk.

[0006] For example, when the circuit breaker needs to be closed, the current in the energy supply device flows to the closing coil disk, so that a repulsive magnetic field is established between the closing coil disk and the eddy current disk after power is supplied. The eddy current disk is repelled and drives the lower pull rod to rise, pushing the moving rod of the vacuum arc chamber to abut against the static rod, thereby achieving closing. When the circuit breaker needs to be opened, the current in the energy supply device flows to the opening coil disk, so that a repulsive magnetic field is established between the opening coil disk and the eddy current disk after power is supplied. The eddy current disk is repelled and drives the lower pull rod to descend, pulling the moving rod of the vacuum arc chamber away from the static rod, thereby achieving opening.

[0007] However, although the eddy current driven direct-acting fast circuit breaker has the advantages of short response time and fast action speed. However, since the energy supply device of the closing coil disk of the fast switch of each phase in the three-phase line is independent, its closing action is also independently controlled. Therefore, in the same closing cycle, when the closing coil disk of the fast switch that needs to be closed first in the three-phase line fails to be energized to complete the closing action first, the fast switch that needs to be closed later will still perform the closing action according to the established procedure. That is, the fast switch that needs to be closed later in the three-phase line completes the closing before the fast switch that needs to be closed first, resulting in an incorrect closing sequence of the surge suppression device, so that the device cannot effectively suppress the closing surge current. Summary of the invention

[0008] In order to solve the problem that the fast switch proposed in the above background technology uses an eddy current driven direct-acting fast circuit breaker, due to the independent existence of the closing coil disk energy supply device in each fast switch, during its application, in the same closing cycle, the fast switch that needs to be closed later in the three-phase line completes closing before the fast switch that needs to be closed first, thereby causing the closing sequence of the surge current suppression device to be wrong, so that the device cannot effectively suppress the closing surge current, the present invention provides the following technical solutions:

[0009] A phase-controlled closing inrush current suppression device includes a fast switch connected in series in each phase line. In each phase line, the fast switch provided in one phase line can share a set of closing power supply device with the fast switch provided in any other phase line outside the phase line; and each fast switch that needs to be synchronously opened and served by the closing power supply device shares a set of opening power supply device.

[0010] in:

[0011] The closing energy supply device includes a closing branch and a suction branch.

[0012] The closing branches correspond one-to-one to the fast switches served by the closing energy supply device, and are used to supply electric energy to the closing coil disk in the corresponding fast switch, and the closing branches are connected in parallel with each other.

[0013] The incoming and outgoing lines of the pickup branch are respectively connected to two closing branches connected in parallel, and the connection point of the outgoing line in the closing branch is located at the incoming line side of the closing coil disk of the fast switch in the closing branch.

[0014] The fast switch in the closing branch connected to the incoming line side of the pickup branch, before the closing coil disk thereof obtains electric energy, the connection point in the closing branch on the outgoing line side of the pickup branch is in an open circuit state.

[0015] Furthermore, the pull-in branch includes a pull-in capacitor, an electromagnetic mechanism, a first contact piece, and a second contact piece.

[0016] When the switch branch connected to the incoming line side of the pickup branch supplies power to the closing coil disk of the fast switch in the closing branch, the pickup capacitor also obtains and stores electrical energy from the closing branch. The electromagnetic mechanism is connected in parallel to the pickup capacitor, and the pickup capacitor provides it with electrical energy. Contact piece 1 and contact piece 2 cooperate with each other to disconnect the switch branch connected to the outgoing line side of the pickup branch, and when the two are in contact, the closing branch is in a connection state, and when the two are separated, the closing branch is in a disconnection state.

[0017] Furthermore, the electromagnetic mechanism includes a coil winding and a magnetic core.

[0018] The coil winding is connected in parallel to the pull-in capacitor to obtain electrical energy from it. The magnetic core is inserted into the central cavity of the coil winding, and its end is connected to contact piece 1 or contact piece 2. When the coil winding is energized, the magnetic core moves, so that contact piece 1 or contact piece 2 connected to the magnetic core moves accordingly, so that contact piece 1 and contact piece 2 are in contact and connected with each other; when the coil winding is de-energized, the magnetic core is reset, so that contact piece 1 or contact piece 2 connected to the magnetic core is reset accordingly, so that contact piece 1 and contact piece 2 are disconnected from each other.

[0019] Furthermore, the closing energy supply device also includes a closing capacitor, a closing thyristor and a charging power supply.

[0020] Each closing branch in the closing energy supply device is connected in series with a combined closing capacitor, and the closing capacitor provides electrical energy to the closing coil disk of the fast switch in the closing branch connected in series. Each closing branch connected in parallel in the closing energy supply device is connected in series with a combined closing thyristor, and the circuit on / off state of the closing branch in which it is located is controlled by the closing thyristor. The charging power supply is connected in parallel with the closing capacitor to replenish electrical energy for the closing capacitor.

[0021] Furthermore, the opening gate energy supply device includes an opening gate branch, an opening gate capacitor, an opening gate thyristor and a charging power supply.

[0022] The switch branches correspond to the fast switches served by the switch power supply device one by one, and are used to supply power to the switch coil disks in the corresponding fast switches, and the switch branches are connected in parallel. The switch branches connected in parallel in the switch power supply device are connected in series with a group of switch capacitors, and the switch capacitors provide power to the switch coil disks of the fast switches in the switch branches connected in series.

[0023] A group of gate thyristors can simultaneously control the on / off state of each gate branch in the gate energy supply device. A charging power source is connected in parallel to the gate capacitor to replenish the gate capacitor with electric energy.

[0024] Furthermore, the phase-controlled closing inrush current suppression device also includes a circuit breaker, a voltage transformer, a current sensor, a suppression device and a controller.

[0025] in:

[0026] The circuit breaker is used to control the on and off of the circuit in conjunction with the fast switch.

[0027] The voltage transformer is connected between the two-phase lines on the incoming side of the circuit breaker.

[0028] A set of current sensors is installed on each phase line on the incoming or outgoing side of the circuit breaker.

[0029] The fast switches in each phase line are each connected in parallel with a set of suppression devices.

[0030] The controller is used to receive, analyze and process the voltage signal of the voltage transformer and the current signal of the current sensor to control the circuit breaker and the fast switch to perform closing and opening actions.

[0031] A closing method is applicable to the above-mentioned phase-controlled closing inrush current suppression device, and the method logic is:

[0032] In the initial state, the circuit breakers and fast switches in each phase line are in the open state.

[0033] During the first closing action, the controller monitors the voltage signal in real time through the voltage transformer. After receiving the closing command, the controller sends a closing command to each circuit breaker, instructing the circuit breaker to complete the closing within the preset closing phase angle range.

[0034] During the second closing action, after the controller sends a closing command to the circuit breaker, it also sends a command to each fast switch in each phase line, commanding each fast switch to complete the closing within its own preset closing phase angle range. In the same closing cycle, the fast switch that needs to be closed first takes precedence over the fast switch that needs to be closed later. If the fast switch that needs to be closed first is not energized and fails to close, the fast switch that needs to be closed later is controlled by the suction branch and cannot be energized to complete the closing.

[0035] When in operation, the circuit breakers and fast switches in each phase line are in the closed state.

[0036] A method for opening the switch is applicable to the above-mentioned phase-controlled closing inrush current suppression device, and the logic of the method is:

[0037] In the initial state, the circuit breakers and fast switches in each phase line are all in the closed state.

[0038] In the first opening action, the controller monitors the voltage signal in real time through the voltage transformer. After receiving the opening command, the controller sends an opening command to each fast switch, instructing each fast switch to complete the opening within the preset opening phase angle range, wherein each fast switch opens synchronously.

[0039] During the second opening action, when the controller sends an opening command to each fast switch, it also sends a command to the circuit breaker, commanding the circuit breaker to complete the opening after a preset time interval after each fast switch completes the opening.

[0040] In the exit state, the circuit breakers and fast switches in each phase line are in the open state.

[0041] Compared with the prior art, the present invention has the following beneficial effects:

[0042] First, the independent closing energy supply devices equipped with some fast switches in the existing equipment are integrated into a set of closing energy supply devices that can be used by these fast switches, which saves at least one set of closing energy supply devices and is conducive to saving equipment costs.

[0043] Second, through the integrated suction branch in the closing energy supply device, when the closing coil disk of the fast switch in the C phase line is not energized first and drives the fast switch in the C phase line to complete the closing, the closing coil disk of the fast switch in the A phase line cannot be energized. In this way, the fast switch in the A phase line cannot be closed before the fast switch in the C phase line is closed, ensuring that the fast switch in the C phase line is closed before the fast switch in the A phase line. That is, it avoids the equipment from being unable to effectively suppress the closing surge current due to the wrong closing sequence of the two fast switches.

[0044] 3. Integrate the independent switch power supply devices equipped with some fast switches in the existing equipment into a set of switch power supply devices that can be used by these fast switches, which saves at least one set of switch power supply devices and is conducive to further saving equipment costs.

[0045] Fourth, through the integrated opening power supply device, after the controller controls the opening thyristor to conduct, the opening capacitor can simultaneously output current to each fast switch it serves, so that these fast switches can be opened synchronously. That is, it avoids the situation where there is an error in the opening of these fast switches due to the different delays in receiving commands when these fast switches are controlled separately, which is conducive to providing accurate phase control of the equipment.

[0046] 5. Through the closing and opening methods of the equipment, the zero-point opening and closing of the equipment can be realized, avoiding arcing of the moving and static contacts in the vacuum interrupter chamber of the fast switch, thereby reducing the loss of the moving and static contacts.

[0047] 6. Through the closing method of the equipment, the phase control method is used to make the switches on the A-phase, B-phase and C-phase lines all complete the closing at a smaller ground voltage phase angle, thereby reducing the inrush current and overvoltage when the equipment is closed and the capacitor bank is put into operation. In addition, the suppression device is used to suppress the inrush current and overvoltage.

[0048] 7. Through the device's opening method, using the phase control method, the switches on the A-phase, B-phase and C-phase lines are all opened at a smaller voltage phase angle, thereby reducing the inrush current and overvoltage when the device is opened and the capacitor bank is exited. In addition, the suppression device is used to suppress the inrush current and overvoltage. BRIEF DESCRIPTION OF THE DRAWINGS

[0049] Figure 1 It is a wiring diagram of the closing inrush current suppression device of the present invention;

[0050] Figure 2 It is a front view of the cabinet of the closing inrush current suppression device of the present invention;

[0051] Figure 3 This is a left view inside the cabinet of the closing inrush current suppression device of the present invention;

[0052] Figure 4 The topology of the closing energy supply device of the closing inrush current suppression device of the present invention Figure 1

[0053] Figure 5 The topology of the closing energy supply device of the closing inrush current suppression device of the present invention Figure 2 ;

[0054] Figure 6 It is a circuit diagram of the pull-in branch of the present invention;

[0055] Figure 7 It is a topological diagram of the opening power supply device of the closing inrush current suppression device of the present invention.

[0056] In the accompanying drawings, the names of the components represented by the reference numerals are listed as follows:

[0057] 01-current sensor, 02-circuit breaker, 03-fast switch, 04-suppression device;

[0058] 100-electromagnetic mechanism, 200-contact piece 1, 300-contact piece 2. DETAILED DESCRIPTION

[0059] The preferred specific embodiments for implementing the present invention are described in detail below, and a clear and complete description is made in conjunction with the accompanying drawings.

[0060] The present invention provides a phase-controlled closing inrush current suppression device. Figures 1 to 3 The device includes a current sensor 01, a voltage transformer, a circuit breaker 02, a fast switch 03, a suppression device 04 and a controller.

[0061] Specific cabinet loading:

[0062] Each phase line of the distribution network feeder is equipped with a current sensor 01 to monitor the current signal of the line; and a voltage transformer is connected between the two-phase lines to monitor the voltage signal of the line.

[0063] Each phase line of the distribution network feeder is equipped with a circuit breaker 02 and a fast switch 03, which cooperate with each other to switch the circuit on and off state of the line where they are both located.

[0064] The fast switches 03 installed on each phase line of the distribution network feeder are each connected in parallel with a suppression device 04 to suppress the surge current and overvoltage generated when the fast switches 03 are closed or opened.

[0065] The current sensor 01, voltage transformer, circuit breaker 02 and fast switch 03 installed on each phase line of the distribution network feeder are all controlled by the controller. The controller controls the circuit breaker 02 and fast switch 03 to close and open by receiving, analyzing and processing the voltage signal of the voltage transformer and the current signal of the current sensor 01.

[0066] Preferably, in the same phase line, the current sensor 01 is located at the incoming line side or the outgoing line side of the circuit breaker 02 .

[0067] Preferably, in the same phase line, the voltage transformer is connected at the incoming line side of the circuit breaker 02 .

[0068] Preferably, in the same phase line, the circuit breaker 02 is located on the incoming line side of the fast switch 03 .

[0069] The present invention provides a phase-controlled closing inrush current suppression device. Figures 4 to 6 Based on the above technical solution, the device also includes a closing energy supply device adapted to more than one closing branch and an opening energy supply device adapted to more than one opening branch.

[0070] In each phase line of the distribution network feeder, the fast switch 03 provided in one phase line can share a set of closing energy supply devices with the fast switch 03 provided in any other phase line outside the phase line, and the set of closing energy supply devices includes a closing branch, a suction branch, a closing capacitor, a closing thyristor and a charging power supply.

[0071] In the same set of closing energy supply device:

[0072] Each closing branch in the closing energy supply device corresponds to the fast switch 03 served by the closing energy supply device, and each closing branch is connected in parallel with each other. The closing branch supplies electric energy to the closing coil disk in the fast switch 03 to which it corresponds.

[0073] The input and output sides of any one of the closing branches in the closing energy supply device are respectively connected to two closing branches connected in parallel, and the connection point of the output side of the closing branch in the closing branch is on the input side of the closing coil disk of the fast switch 03 in the closing branch.

[0074] Each closing branch in the closing energy supply device is connected in series with a combination of closing capacitors, and the closing capacitor provides electrical energy to the closing coil disk of the fast switch 03 in the closing branch connected in series.

[0075] Each closing branch in the closing energy supply device is connected in series with a combination of thyristors, and the closing thyristors control the on-off state of the circuit of the closing branch in which they are located.

[0076] The charging power supply in the closing energy supply device is connected in parallel with the closing capacitor to replenish electric energy for the closing capacitor.

[0077] Furthermore, the pull-in branch includes a pull-in capacitor, an electromagnetic mechanism 100, a contact piece 1 200 and a contact piece 2 300. When the closing capacitor supplies power to the closing coil disk of the fast switch 03 in the closing branch connected to the incoming line side of the pull-in branch, the pull-in capacitor of the pull-in branch will also obtain electrical energy from the closing branch and store it. The electromagnetic mechanism 100 is connected in parallel to the pull-in capacitor, and the pull-in capacitor provides it with electrical energy. The contact piece 1 200 and the contact piece 2 300 cooperate with each other to disconnect the closing branch connected to the outgoing line side of the pull-in branch, and when the two are in contact, the closing branch is in a pass state, and when the two are separated, the closing branch is in a disconnected state.

[0078] Furthermore, the electromagnetic mechanism 100 includes a coil winding and a magnetic core. The coil winding is connected in parallel to the pull-in capacitor, and the magnetic core is inserted into the central cavity of the coil winding, and the end of the magnetic core is connected to the contact piece 1 200 or the contact piece 2 300 .

[0079] In the specific application of the same set of closing energy supply device:

[0080] When the closing capacitor supplies power to the closing coil disk of the fast switch 03 in the closing branch connected to the incoming line side of the pickup branch, the closing coil disk of the fast switch 03 cooperates with the eddy current disk to generate a repulsive magnetic field to drive the moving rod of the vacuum interrupter in the fast switch 03 to push toward the stationary rod of the vacuum interrupter, thereby completing the closing of the fast switch 03.

[0081] At the same time, the closing capacitor will also supply power to the closing capacitor of the closing branch through the closing branch connected to the incoming line side of the closing branch. After the closing capacitor obtains electrical energy, it will supply the electrical energy to the coil winding. When the coil winding is energized, a magnetic field is established to move the magnetic core, thereby causing the contact piece 200 or the contact piece 2 300 connected to the magnetic core to move accordingly, so that the contact piece 1 200 and the contact piece 2 300 are in contact and connected with each other.

[0082] At this time, the gate branch connected to the outgoing line side of the pickup branch is in a pass state. In this state, by controlling the closing thyristor connected in series to the gate branch connected to the outgoing line side of the pickup branch to conduct, the closing capacitor can supply power to the closing coil disk of the fast switch 03 in the gate branch connected to the outgoing line side of the pickup branch, and close the fast switch 03 in the gate branch connected to the outgoing line side of the pickup branch.

[0083] In this way, before the fast switch 03 in the gate branch connected to the incoming line side of the absorbing branch is closed, since the contact piece 1 200 and the contact piece 2 300 in the gate branch connected to the outgoing line side of the absorbing branch are not in contact, the gate branch connected to the outgoing line side of the absorbing branch is in an open circuit state. Therefore, when the closing thyristor connected in series with the gate branch connected to the outgoing line side of the absorbing branch is turned on, the closing capacitor cannot supply power to the fast switch 03 in this branch through the gate branch connected to the outgoing line side of the absorbing branch. That is, before the fast switch 03 in the gate branch connected to the incoming line side of the absorbing branch is closed, the fast switch 03 in the gate branch connected to the outgoing line side of the absorbing branch cannot be closed.

[0084] In addition, when the electric energy of the pull-in capacitor is insufficient to maintain the magnetic field formed by the coil winding when it is energized, the magnetic field disappears, and the magnetic poles of the coil winding return to the state when it is not energized, so that the magnetic core is reset, and the contact piece 1 200 or the contact piece 2 300 connected to the magnetic core is reset accordingly. That is, the contact piece 1 200 and the contact piece 2 300 are disconnected from each other.

[0085] In each phase line of the distribution network feeder, the fast switch 03 provided in one phase line can share a set of disconnection energy supply devices with the fast switch 03 provided in any other phase line outside the phase line, and the set of disconnection energy supply devices includes disconnection branches, disconnection capacitors, disconnection thyristors and charging power supplies.

[0086] In the same set of opening energy supply device:

[0087] Each of the branch circuits in the gate-opening energy supply device corresponds to the fast switch 03 served by the gate-opening energy supply device, and each of the branch circuits is connected in parallel with each other. The gate-opening branch supplies electric energy to the gate-opening coil disk in the fast switch 03 to which it corresponds.

[0088] Each of the opening branches in the opening energy supply device is connected in series with a group of opening capacitors, and the opening capacitors provide electrical energy to the opening coil disk of the fast switch 03 in the opening branch connected in series.

[0089] Each branch circuit in the branch circuit energy supply device is connected in series with a group of branch circuit thyristors, and the branch circuit thyristors control the on-off state of the circuit of the branch circuit in which they are located.

[0090] The charging power supply in the opening switch energy supply device is connected in parallel with the opening switch capacitor to replenish electric energy for the opening switch capacitor.

[0091] In the specific application of the same set of opening energy supply device:

[0092] After the opening thyristor is turned on by the controller, the opening capacitor simultaneously supplies power to the opening coil disks of the fast switches 03 in all the opening branches connected to it. In these fast switches 03, the opening coil disk of each fast switch 03 cooperates with its corresponding eddy current disk to generate a repulsive magnetic field to drive the moving rod of the vacuum interrupter in the fast switch 03 to leave the static rod of the vacuum interrupter, so that the fast switch 03 is opened. That is, the synchronous opening of each fast switch 03 is completed.

[0093] The present invention provides a closing method, which is applicable to the above-mentioned phase-controlled closing inrush current suppression device, and the method logic is:

[0094] In the initial state, the circuit breaker 02 and the fast switch 03 in each phase line are in the open state.

[0095] In the first closing action, the controller monitors the voltage signal in real time through the voltage transformer. After receiving the closing command, the controller sends a closing command to each circuit breaker 02, instructing the circuit breaker 02 to complete the closing within the preset closing phase angle range.

[0096] In the second closing action, after the controller sends a closing command to the circuit breaker 02, it also sends a command to each fast switch 03 in each phase line, instructing each fast switch 03 to complete the closing within the respective preset closing phase angle range. Among them, the fast switch 03 that needs to be closed first has priority over the fast switch 03 that needs to be closed later. If the fast switch 03 that needs to be closed first is not energized and thus fails to close, the fast switch 03 that needs to be closed later cannot be energized to complete the closing due to the control of the suction branch.

[0097] In the operational state, the circuit breaker 02 and the fast switch 03 in each phase line are in the closed state.

[0098] The present invention provides a switch-off method, which is applicable to the above-mentioned phase-controlled closing inrush current suppression device, and the method logic is:

[0099] In the initial state, the circuit breaker 02 and the fast switch 03 in each phase line are in the closed state.

[0100] In the first opening action, the controller monitors the voltage signal in real time through the voltage transformer. After receiving the opening command, the controller sends an opening command to each fast switch 03, instructing each fast switch 03 to complete the opening within the preset opening phase angle range. Among them, each fast switch 03 opens synchronously.

[0101] In the second opening action, when the controller sends an opening command to each fast switch 03, it also sends a command to the circuit breaker 02, instructing the circuit breaker 02 to complete the opening after a preset time interval after each fast switch 03 completes the opening.

[0102] In the exit state, the circuit breaker 02 and the fast switch 03 in each phase line are in the open state.

[0103] In summary, in the above technical solution provided by the present invention, the inrush current is minimized when the voltage crosses zero angle, and the closing and opening angles of the fast switch 03 in each phase line are preferably closed and opened when the voltage of each phase line crosses zero. In addition, by connecting the suppression device 04 in parallel to the fast switch 03, the inrush current and overvoltage generated when the fast switch 03 is closed and opened are suppressed and absorbed by the suppression device 04.

[0104] Embodiment 1

[0105] See also Figure 4 This embodiment takes the three-phase line of phase A, phase B and phase C as an example, and provides a solution in which the fast switches 03 installed on the two-phase lines of phase A and phase C share a set of closing energy supply devices.

[0106] In the application of this embodiment:

[0107] After the phase-controlled closing inrush current suppression device is put into operation on the three-phase feeder of the distribution network, its initial state is that the circuit breaker 02 and the fast switch 03 in the three-phase line of phase A, phase B and phase C are all in the open state. Among them, the circuit breaker 02 is a three-phase circuit breaker.

[0108] When the capacitor bank connected to the load side of the equipment needs to be put into operation in the distribution network system for reactive power compensation, the switching action logic of the circuit breaker 02 and the fast switch 03 is:

[0109] In the first closing action, the controller monitors the voltage signal in real time through the voltage transformer. After receiving the closing command, the controller sends a closing command to the circuit breaker 02, and the circuit breaker 02 completes the closing within the preset closing phase angle range. That is, at this time, the lines at the position of the circuit breaker 02 in the three-phase lines of phases A, B and C are all in the open state.

[0110] In the second closing action, after the controller controls the circuit breaker 02 to complete closing, it controls the fast switch 03 in the B phase line to complete closing within its preset closing phase angle range, then controls the fast switch 03 in the C phase line to complete closing within its preset closing phase angle range, and finally controls the fast switch 03 in the A phase line to complete closing within its preset closing phase angle range.

[0111] After completing the above actions, the circuit breakers 02 and fast switches 03 in the three-phase lines of phases A, B and C are all in the closed state, and the capacitor group for reactive power compensation of the distribution network system is put into operation and enters the operation state.

[0112] In the same closing cycle, the fast switch 03 in the C phase line is closed before the fast switch 03 in the A phase line. If the fast switch 03 in the C phase line fails to obtain the electric energy supplied by the closing capacitor and fails to close, the fast switch 03 in the A phase line is controlled by the suction branch to make the closing branch where it is located in an open circuit state. In this way, even if the controller controls the closing thyristor of the closing branch where the fast switch 03 in the A phase line is located to be turned on, the electric energy of the closing capacitor cannot be supplied to the fast switch 03 in the A phase line, so that the fast switch 03 in the A phase line cannot be closed before the fast switch 03 in the C phase line is closed.

[0113] It should be noted that in this embodiment, the same closing cycle is calculated according to one cycle of the voltage sine wave, and its starting point is defined as the closing angle of the fast switch 03 in the B-phase line. That is, if the closing angle of the fast switch 03 in the B-phase line is X°, then the range of the same closing cycle is X° to (X+360)°.

[0114] Embodiment 2

[0115] See also Figure 5 This embodiment takes the three-phase circuit of phase A, phase B and phase C as an example, and provides a solution in which the fast switches 03 installed on the three-phase circuit of phase A, phase B and phase C share a set of closing energy supply devices.

[0116] In the application of this embodiment:

[0117] After the phase-controlled closing inrush current suppression device is put into operation on the three-phase feeder of the distribution network, its initial state is that the circuit breaker 02 and the fast switch 03 in the three-phase line of phase A, phase B and phase C are all in the open state. Among them, the circuit breaker 02 is a three-phase circuit breaker.

[0118] When the capacitor bank connected to the load side of the equipment needs to be put into operation in the distribution network system for reactive power compensation, the switching action logic of the circuit breaker 02 and the fast switch 03 is:

[0119] In the first closing action, the controller monitors the voltage signal in real time through the voltage transformer. After receiving the closing command, the controller sends a closing command to the circuit breaker 02, and the circuit breaker 02 completes the closing within the preset closing phase angle range. That is, at this time, the lines at the position of the circuit breaker 02 in the three-phase lines of phases A, B and C are all in the open state.

[0120] In the second closing action, after the controller controls the circuit breaker 02 to complete closing, it controls the fast switch 03 in the B phase line to complete closing within its preset closing phase angle range, then controls the fast switch 03 in the C phase line to complete closing within its preset closing phase angle range, and finally controls the fast switch 03 in the A phase line to complete closing within its preset closing phase angle range.

[0121] After completing the above actions, the circuit breakers 02 and fast switches 03 in the three-phase lines of phases A, B and C are all in the closed state, and the capacitor group for reactive power compensation of the distribution network system is put into operation and enters the operation state.

[0122] In the same closing cycle, the fast switch 03 in the B-phase circuit is closed before the fast switches 03 in the A-phase and C-phase circuits, and the fast switch 03 in the C-phase circuit is closed before the fast switch 03 in the A-phase circuit. If the fast switch 03 in the C-phase circuit fails to obtain the electric energy supplied by the closing capacitor and fails to close, the fast switch 03 in the A-phase circuit is controlled by the suction branch to make the closing branch where the fast switch 03 is located in the A-phase circuit in an open circuit state. In this way, even if the controller controls the closing thyristor of the closing branch where the fast switch 03 in the A-phase circuit is located to be turned on, the electric energy of the closing capacitor cannot be supplied to the fast switch 03 in the A-phase circuit, so that the fast switch 03 in the A-phase circuit cannot be closed before the fast switch 03 in the C-phase circuit is closed. Similarly, if the fast switch 03 in the B-phase circuit fails to obtain the electric energy supplied by the closing capacitor and fails to close, the fast switch 03 in the C-phase circuit cannot be closed before the fast switch 03 in the B-phase circuit is closed.

[0123] It should be noted that in this embodiment, the same closing cycle is calculated according to one cycle of the voltage sine wave, and its starting point is defined as the closing angle of the fast switch 03 in the B-phase line. That is, if the closing angle of the fast switch 03 in the B-phase line is X°, then the range of the same closing cycle is X° to (X+360)°.

[0124] Embodiment 3

[0125] See also Figure 7 This embodiment takes the three-phase line of phase A, phase B and phase C as an example, and provides a solution in which the fast switches 03 installed on the two-phase lines of phase A and phase C share a set of disconnection energy supply devices.

[0126] In the application of this embodiment:

[0127] After the phase-controlled closing inrush current suppression device is put into operation on the three-phase feeder of the distribution network and the reactive power compensation capacitor bank of the distribution network system on the load side of the device is put into operation, the initial state is that the circuit breaker 02 and the fast switch 03 in the three-phase line of phase A, phase B and phase C are all in the closed state. Among them, the circuit breaker 02 is a three-phase circuit breaker.

[0128] When the capacitor bank connected to the load side of the equipment needs to be removed from the distribution network system, the switching action logic of the circuit breaker 02 and the fast switch 03 is:

[0129] During the first opening action, the controller monitors the voltage signal in real time through the voltage transformer. After receiving the opening command, the controller sends an opening command to the fast switches 03 in the A-phase and C-phase lines, commanding the two fast switches 03 to complete the opening synchronously within the preset opening phase angle range.

[0130] In the second opening action, after the fast switch 03 in the two-phase circuit of phase A and phase C completes the opening, the controller sends an opening command to the fast switch 03 in the phase B circuit, and then sends a command to the circuit breaker 02, commanding the circuit breaker 02 to complete the opening after a preset time interval after the fast switch 03 in the three-phase circuit of phase A, phase B and phase C completes the opening.

[0131] After completing the above actions, the circuit breaker 02 and the fast switch 03 in the three-phase lines of phases A, B and C are all in the open state, and the capacitor group used for reactive power compensation in the distribution network system is successfully disconnected from the grid and enters the exit state.

[0132] Based on the above content and the accompanying drawings, those skilled in the art can understand and implement the present invention. In addition, any non-creative modifications made to the present invention by those skilled in the art without creative work still fall within the protection scope of the present invention.

Claims

1. A phase-controlled closing inrush current suppression device, comprising a fast switch (03) connected in series in each phase line, characterized in that: In each phase line, a fast switch (03) provided in one phase line can share a set of closing energy supply device with a fast switch (03) provided in any other phase line outside the phase line, and the closing energy supply device includes: Closing branches, which correspond one to one with the fast switches (03) served by the closing energy supply device, are used to supply electric energy to the closing coil disk in the corresponding fast switch (03), and the closing branches are connected in parallel with each other; The inlet and outlet sides of the pickup branch are respectively connected to two closing branches connected in parallel, and the connection point of the outlet side in the closing branch is located at the inlet side of the closing coil disk of the fast switch (03) in the closing branch; The fast switch (03) in the closing branch connected to the incoming line side of the said suction branch has a connection point in the closing branch on the outgoing line side in the closing branch in an open circuit state before the closing coil disk thereof obtains electric energy.

2. The phase-controlled closing inrush current suppression device according to claim 1 is characterized in that: The pull-in branch includes: The pull-in capacitor, when the closing branch connected to the incoming line side of the pull-in branch supplies power to the closing coil disk of the fast switch (03) in the closing branch, the pull-in capacitor also obtains electric energy from the closing branch and stores it; The electromagnetic mechanism (100) is connected in parallel to the pull-in capacitor and is provided with electric energy by the pull-in capacitor; Contact piece 1 (200) and contact piece 2 (300) cooperate with each other to disconnect the switch branch connected to the outgoing line side of the suction branch, and when the two are in contact, the switch branch is in a connection state, and when the two are separated, the switch branch is in a disconnection state.

3. The phase-controlled closing inrush current suppression device according to claim 2 is characterized in that: The electromagnetic mechanism (100) comprises: The coil winding is connected in parallel with the pull-in capacitor to obtain electrical energy; A magnetic core, inserted into the central cavity of the coil winding, and having an end connected to the first contact piece (200) or the second contact piece (300); When the coil winding is energized, the magnetic core moves, thereby causing the contact piece 1 (200) or the contact piece 2 (300) connected to the magnetic core to move accordingly, so that the contact piece 1 (200) and the contact piece 2 (300) are in contact and connected with each other; After the coil winding is powered off, the magnetic core is reset, thereby resetting the contact piece 1 (200) or the contact piece 2 (300) connected to the magnetic core, so that the contact piece 1 (200) and the contact piece 2 (300) are disconnected from each other.

4. The phase-controlled closing inrush current suppression device according to any one of claims 1 to 3, characterized in that: The closing energy supply device also includes: A closing capacitor, each closing branch in the closing energy supply device is connected in series with a group of closing capacitors, and the closing capacitor provides electric energy to the closing coil disk of the fast switch (03) in the closing branch connected in series; A closing thyristor, each of the closing branches connected in parallel in the closing energy supply device is connected in series with a combination of closing thyristors, and the closing thyristors control the on-off state of the circuit of the closing branch in which they are located; The charging power supply is connected in parallel to the closing capacitor and is used to replenish electric energy for the closing capacitor.

5. The phase-controlled closing inrush current suppression device according to claim 4 is characterized in that: In each phase line, each fast switch (03) that needs to be opened synchronously and served by the closing energy supply device shares a set of opening energy supply device, and the opening energy supply device includes: The opening branches correspond one to one with the fast switches (03) served by the opening energy supply device, and are used to supply electric energy to the opening coil disk in the corresponding fast switch (03), and the opening branches are connected in parallel with each other; A disconnecting capacitor, wherein each disconnecting branch connected in parallel in the disconnecting energy supply device is connected in series with a group of disconnecting capacitors, and the disconnecting capacitors provide electrical energy to the disconnecting coil disk of the fast switch (03) in the disconnecting branch connected in series; A split-gate thyristor, each split-gate branch connected in parallel in the split-gate energy supply device is connected in series with a group of split-gate thyristors, and the split-gate thyristors simultaneously control the circuit on-off state of each split-gate branch in the split-gate energy supply device; The charging power supply is connected in parallel to the disconnecting capacitor and is used to replenish electric energy for the disconnecting capacitor.

6. The phase-controlled closing inrush current suppression device according to claim 5 is characterized in that: The device also includes: A circuit breaker (02) is used to cooperate with a fast switch (03) to control the on and off of the circuit; A voltage transformer is connected between two phases of the incoming line side of the circuit breaker (02); The current sensor (01) is installed on each phase line on the incoming or outgoing side of the circuit breaker (02); The suppression device (04) is connected in parallel to the fast switch (03) in each phase line; The controller is used for receiving, analyzing and processing the voltage signal of the voltage transformer and the current signal of the current sensor (01) to control the circuit breaker (02) and the fast switch (03) to perform closing and opening actions.

7. A closing method, applicable to the phase-controlled closing inrush current suppression device according to claim 6, characterized in that: In the initial state, the circuit breaker (02) and the fast switch (03) in each phase line are in the open state; During the first closing action, the controller monitors the voltage signal in real time through the voltage transformer. After receiving the closing command, the controller sends a closing command to each circuit breaker (02), instructing the circuit breaker (02) to complete closing within a preset closing phase angle range; In the second closing action, after the controller sends a closing command to the circuit breaker (02), it simultaneously sends a command to each fast switch (03) in each phase line, instructing each fast switch (03) to complete closing within the respective preset closing phase angle range, wherein the fast switch (03) that needs to be closed first has priority over the fast switch (03) that needs to be closed later. If the fast switch (03) that needs to be closed first is not energized and thus fails to close, the fast switch (03) that needs to be closed later is controlled by the suction branch and cannot be energized to complete closing; In the operational state, the circuit breakers (02) and fast switches (03) in each phase line are all in the closed state.

8. A method for opening a circuit breaker, applicable to the phase-controlled closing inrush current suppression device according to claim 6, characterized in that: In the initial state, the circuit breaker (02) and the fast switch (03) in each phase line are in the closed state; During the first opening action, the controller monitors the voltage signal in real time through the voltage transformer. After receiving the opening command, the controller sends an opening command to each fast switch (03), instructing each fast switch (03) to complete the opening within a preset opening phase angle range, wherein each fast switch (03) opens synchronously; In the second opening action, when the controller sends an opening command to each fast switch (03), it also sends a command to the circuit breaker (02) to complete the opening after a preset time interval after each fast switch (03) completes the opening; In the exit state, the circuit breakers (02) and fast switches (03) in each phase line are in the open state.

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