JPS5855442Y2 - Jump control circuit in sequence control - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a jump control circuit in sequence control, and particularly relates to an improvement of a jump control circuit in sequence control using a relay.

Conventionally, this type of jump control circuit has provided its function by using a large number of auxiliary relays or by using transistors, ICs, or other static circuits.

However, since static circuits are constructed on a printed circuit board and require a power supply, it is necessary to limit the use and scale of the circuit, which may not be cost-effective or have reliability problems. .

On the other hand, systems using relays require a large number of relays, making it difficult to create a compact device.

This invention uses a make-before-break relay for each controlled object, one for jump and one for self-holding, thereby creating a jump circuit in sequence control that uses fewer relays and is more compact. The purpose is to provide.

As an embodiment of the present invention, a circuit will be described below with reference to the drawings, which performs skippable sequential control of capacitors in each bank depending on the reactive power of the load in a variable power plant.

FIG. 1 is a schematic explanatory diagram of a reactive power control device, in which reactive power of a load 2 connected to a power line 1 is detected by a reactive power detection unit 5 using a voltage transformer 3 and a current transformer 4. When the detection value exceeds the set value, the reactive power sequence control unit 6 sequentially controls each capacitor master SC1 to SCN so that they can be skipped.

Note that 7 is a power main circuit breaker, and 8 is a capacitor main circuit breaker.

FIG. 2 shows a jumpable sequence control circuit according to the present invention. Reference numeral 100 denotes a control operation relay, which is composed of a normally open contact 2X and a normally closed contact 66, which operate according to commands from the sequence control unit 6 shown in FIG. One end is connected to the lead wire 11 from the power supply, and the other end is a make-before-break contact (hereinafter referred to as MBB contact) via contact 66.
It is connected in series with the control command start □ relay XO having XOl and XO2.

X1 to XN are capacitor switching relays, X1' to XN'
, X1'' to XN'' and Xl to XN are contacts of capacitor switching relays X1 to XN, respectively.

A1. A2...AN is closed by the MBBBBr2 second control command that is skipped over MBBBBr2 for each control capacitor jump.

The make contact of this MBB contact A1 is connected to the tongue terminal of MBB contact XO2 for starting the control command, and the tongue terminal of MBB contact A1 is connected to the make contact of the jump MBB contact, and is connected to contact X1'. Connected.

The break contact of contact A1 is connected to the capacitor switching relay X1 via the break contact of contact X1''.

MBB contact A2...AN repeats the same connection, and MB
The tongue terminal of the B contact AN is connected to the power supply lead wire 14.

AH', A2'...AN' is MB for self-holding switching
A bridge circuit consisting of a B contact and a capacitor S
It is for self-holding of the MBB contact for jump control of C1-SCN.

Note that this contact point AI'...AN' is used for the above-mentioned jump M.
BB contact A1. A2...The capacitor that is skipped in the same way as AN is closed in advance by a control command.

The break terminal of MBB contact A1' is MBB contact X1'''
The MBB contact X1'' is connected to the power supply lead wire 11 through the make terminal and the break contact, and the tongue terminal of this MBB contact X1'' is connected to the contact 66 by the lead wire 16.

The tongue terminal of MBB contact AI' is connected to the self-holding circuit of the control switching relay X1, and the MB for self-holding switching
It is connected in series to the make contact of B contact A2'.

The break contact of this MBB contact A2' is MBB contact
The relay 66 is connected via the make contact of 2 and the terminal on one side of the tongue.
is connected to the lead wire 16 from the terminal of M.
The break contact of BBBBr2 is connected to the power supply lead 11.

Further, the terminal of the lead wire 16 is connected to the normally closed terminal of the switching contact XN'.

Self-holding switching MBB contacts A3', A4'...
The same connection is repeated for AN', and the terminal on one side of the MBB contact AN' is connected to the power supply lead wire 11.

In the present invention having the above configuration, the normally closed contact 2X is turned on at time to in the time chart shown in FIG. → Break contact of MBB contact Xo2 for control start → Normally closed contact X1' of switching relay of control capacitor SC1 → X2' →・
... → Each normally closed contact of XN-1 → Lead wire 14 → Excitation coil of control start relay XO → - Lead wire 12 of power supply
A current flows through the circuit to energize the starting relay XO of the control.

Now, the operation when the control capacitors S1 to SCN shown in FIG. 1 are sequentially controlled without skipping control will be explained.

By closing contact XO2 by energizing relay XO, power supply lead 11 → contact 2X → contact 66 → lead wire 13 → MB
Make contact of B contact XO2 → Jumping MBB contact A1
Break contact → control capacitor switching control relay
Current flows from the excitation coil of the machine to the lead wire 12 of the power supply, energizing relay X1.

Therefore, the operation signal of relay X1 is
Capacitor SC1 is selected through a selection circuit consisting of a circuit, etc., and the circuit breaker of SC1 is turned on to connect SC1 to the electric circuit, and at the same time, self-holding contact X1'' is closed.

Therefore, at time t1 shown in FIG.
Even when contact 2X is turned off, relay
Current flows through the break contact of the MBB contact X2 of the switching control relay X2 of No. 2 → the break contact of the MBB contact A2' for self-holding switching → the self-holding contact X1'' of the relay X1.
is self-maintained.

At time t2 shown in FIG. 3, the contact 2X is turned off and the contact 66 is turned on by the control command, but at time t3, an on command is again given to the contact 2X and it is turned on.

Since the contact XO2 is already in the OFF state due to the deenergization of the relay XO, and the contact X1' is in the ON state due to the energization of the relay Contact X1' → Break contact of jump MBB contact A2 → Excitation coil of switching control relay X2 of control capacitor SC2 → - Current flows in the closed circuit of power supply lead wire 12 relay X2
is energized, capacitor C2 is turned on, and X2 is also self-held in the same way as relay X1.

Relay X2 turns on and at time t4 contact X2
When is turned on, the self-holding circuit of relay X2 is opened,
Relay X1 falls off.

However, even if Xl falls off, capacitor SC1 is already
Since the capacitor SC1 is selected and turned on at the time when it is turned on, the capacitor SC1 will not be released due to this falling off.
00 is repeatedly turned on and off in sequence, and the capacitors SC3 to corresponding to the respective relays X3 to XN
The SCNs are also sequentially selected and connected to the electric circuit.

Next, in the above order control, for example, capacitor SC2,
Assuming that SC4, SC5, and SC7 are skipped, the operation of controlling the order from capacitor SC1 to capacitor SC3 will be described first.

In this case, the capacitor SC2 is
, SC4° SC5, SC7 equivalent MBB
Contact point A2.

A4. A5. A7 and self-holding MBB contact A2'.

A4', A6', and A7' are loaded in advance.

After that, a control command is given to the control operation relay 100, but the steps until the control relay X1 of the capacitor SC1 is energized are the same as in the sequential control.

In addition, in this case, the self-holding of relay X1 is done by contact A.
11→X3 because 2′ is inserted in advance
It is self-maintained by a closed circuit of ''→X3'→A2'→X1''.

At time t3, when the second on signal is input to 2X,
Since the jump MBB contact A2 is turned on in advance, the make contact and the break contact of this MBB contact A2 are turned off, so that the capacitor SC2
The excitation coil of relay X2, which controls switching, is not energized, and therefore capacitor SC2 is not controlled.

At the same time, ten power lead wires 11 → contact 2X → contact 6
6 → Break contact of MBB contact XO2 → Contact X1'-M
Make contact of BB contact A2 → Break contact of MBB contact A3 4 Excitation coil of relay It jumps over and relay X3 is energized.

The self-holding circuit of rule X3 is operated via the self-holding switching contact X3°A4' in exactly the same manner as described for the sequential control circuit.

Further, the skipping operations of SC4, SC5, and SC7 are performed in the same manner.

In the above explanation, only the operation of turning on the capacitor has been explained, but it is performed in exactly the same way when the capacitor is disconnected from the electric circuit after it has been turned on. This can easily be done by using the circuit breaker as a trip signal.

As described above, in order control that allows for jump control, the present invention connects the jump MBB contact 8 provided for the skipped capacitor, for example, SC2, to the self-holding MBB.
Since contact A2' is closed in advance, relay X2
Since relay X3 is directly operated from relay X1 without controlling relay X3, there is no need for wasted time due to jumping.

Furthermore, since the control circuit has circuits of the same type connected in series for each controlled object, the circuit configuration is easy, and the jump contact has a make-before-break,
Since the number of relays used is reduced by using individual contacts, the device becomes compact.

Therefore, when sequentially controlling the capacitors installed in each bank according to the reactive power of the load on the power transmission and distribution line, it is possible to skip the faulty capacitor and shorten the time required for control. Can be made smaller.

Furthermore, for example, when you want to skip over a failed pump when controlling the number of pumps in a water supply control system, or when you want to arbitrarily select a program to be excluded from the order in advance for load limiting, the order of power transmission and distribution lines, etc. In general, when it is desired to perform jump control over a plurality of control objects, the present invention has great practical effects, such as being able to perform control quickly and smoothly without getting stuck midway.

[Brief explanation of the drawing]

FIG. 1 is a schematic explanatory diagram of the reactive power control device, and the second
FIGS. A and B show an example of a sequence control circuit according to the present invention, and FIG. 3 is a time chart that operates based on the control command in FIG. 2. 6... Reactive power control unit, SC1 to SCN...
Control capacitor of each bank, 2X, 66... Normally open contact and normally closed contact operated by control command, XO... MBB contact for control start, Xl, X2. XN...Relay that switches and controls the control capacitor, X1', X2'
...XN'...Control relay switching contact, X1'', X
2'', XN''...Self-holding contact of control relay, A1.
A2...AN...MBB contact for skipping, AI'
, A2 '...AN'... MBB for self-holding switching
contact.

Claims (1)

[Scope of utility model registration request] In addition to connecting the contacts of the control operation relay to the power supply, a plurality of controlled object switching relay contacts are connected in series between the non-power side and the ground side of this operation relay, and the contacts are made to correspond to the switching relay contacts for self-maintenance. A sequence control circuit that includes a relay and sequentially controls each switching relay contact by giving an external control command to the control operation relay,
A jump control relay contact is inserted between the open side contacts of the contacts of each of the switching relays, and the self-holding is connected between the non-power terminal of the operation relay and each of the self-holding relays in correspondence with the jump control relay contact. A bridge circuit for contact switching is provided, and the bridge circuit is MBB (make before
Jump control in sequence control, characterized in that the jump control is configured with (brake) contacts and enables desired jump control by controlling each jump control relay contact and bridge circuit based on a predetermined jump control command from the outside. circuit.