disclosure of Invention
Aiming at the problems, the invention provides an automatic switching system of an alternating current ring network power supply and an operation monitoring method thereof in order to solve the defects in the prior art.
The technical scheme of the invention is as follows:
an automatic switching system of an alternating current looped network power supply is characterized in that two sides of an alternating current looped network loop are respectively and additionally provided with two alternating current contactors C1 and C2 and two voltage intermediate relays ZJ1 and ZJ 2; an auxiliary switch is additionally arranged on the looped network power supply air switches K1 and K6 in the terminal box, and an alternating current contactor C2-1 and an alternating current contactor C5-2 are additionally arranged on the load sides of the looped network power supply air switches K1 and K6 respectively; two auxiliary switches are additionally arranged on ring network power supply air switches K2, K3, K4 and K5 respectively, and an alternating current contactor C1-2, C3-1, C2-2, C4-1, C3-2, C5-1, C4-2 and C6-1 are additionally arranged on two sides of the ring network power supply air switches K2, K3, K4 and K5 respectively, so that power monitoring of an alternating current ring network loop and functions of cutting off a fault section alternating current ring network and power backup switching are realized, and corresponding signals of 'alternating current ring network power supply I fault', 'alternating current ring network power supply II fault' and 'alternating current fault' are sent out at a monitoring background by switching on a measurement and control device through normally closed contacts of a voltage intermediate relay ZJ1 and a ZJ2 and normally open contacts of an alternating current contactor C1 and a C2;
when the alternating current ring network power supply loses voltage or a certain section of the ring network power supply is abnormal, the corresponding air switch on the power supply side trips to start the standby power supply switching device, the ring network on the fault section is automatically cut off, the standby power supply on the other side is switched on, meanwhile, a corresponding fault signal is sent out to remind monitoring personnel, and operation and maintenance personnel are informed to check and process in time.
Two voltage intermediate relays ZJ1 and ZJ2 for power supply monitoring, two AC contactors C1 and C2 for automatic switching of two ring network power supplies are additionally arranged in loops at two sides of an AC ring network, a fault occurs at a certain section of the ring network, an auxiliary switch is additionally arranged on ring network power supply air switches K1 and K6 in a standby power supply starting loop-terminal box, an AC contactor C2-1 and C5-2 are additionally arranged at load sides of ring network power supply air switches K1 and K6 respectively, two auxiliary switches are additionally arranged on switches K2, K3, K4 and K5 respectively, and an AC contactor C1-2, C3-1, C2-2, C4-1, C3-2, C5-1, C4-2 and C6-1 are additionally arranged at two sides of ring network power supply air switches K2, K3, K4 and K5 respectively, so that the fault-free ring network power supply can be recovered quickly;
when the voltage of the ring network power supply is lost due to failure, the voltage intermediate relays ZJ1 and ZJ2 are demagnetized, the normally closed contact is closed, the coil loop of the fault-free AC contactor C1 or C2 is connected, and the AC contactor is excited to be used as the standby ring network power supply.
When a certain section of the alternating current looped network is in fault, an air switch K1 or K2 or K3 or K4 or K5 or K6 on the looped network power supply side of the section trips, an auxiliary normally closed contact of the section trips, a coil loop C1-2 or C3-1 or C2-2 or C4-1 or C3-2 or C5-1 or C4-2 or C6-1 of a standby power supply side alternating current contactor of the fault section is switched on, an alternating current contactor of the section is excited, a main normally closed contact opens and cuts off the alternating current looped network of the fault section, a normally open auxiliary contact is switched on, a coil starting loop C1 or C2 of the standby power supply side alternating current contactor is switched on, and a standby power supply side alternating current contactor C1 or C2 of the fault-free looped network.
When any AC looped network power supply loses voltage, the voltage intermediate relays ZJ1 and ZJ2 with power supply monitoring lose magnetism, the normally closed contact is connected with the measurement and control device, and the monitoring background sends out a corresponding AC looped network power supply fault signal.
When a certain section of ring network has a fault, after the fault section of ring network is cut off, the standby ring network power supply AC contactor C1 or C2 is automatically switched on, the AC contactor C1 or C2 on two sides is opened for closing an auxiliary contact, a measurement and control device is switched on, and a monitoring background sends an AC ring network fault signal.
The main advantages of the invention are:
1. when any alternating current ring network power supply loses voltage, the standby power supply can be automatically switched on, and a fault signal of the corresponding ring network power supply is sent out through the monitoring background.
2. When a certain section of ring network has a fault, the fault section can be automatically cut off, a standby power supply at the other side is put into use, a power supply mode at two sides is realized, the power supply of a normal ring network is recovered, and an alternating current ring network fault signal is sent out through a monitoring background.
Detailed Description
The present invention is described in detail below by way of examples.
Example 1
Two sides of an alternating current looped network circuit are respectively provided with two alternating current contactors C1 and C2 and two voltage intermediate relays ZJ1 and ZJ 2; an auxiliary switch is additionally arranged on the looped network power supply air switches K1 and K6 in the terminal box, and an alternating current contactor C2-1 and an alternating current contactor C5-2 are additionally arranged on the load sides of the looped network power supply air switches K1 and K6 respectively; two auxiliary switches are additionally arranged on ring network power supply air switches K2, K3, K4 and K5 respectively, and an alternating current contactor C1-2, C3-1, C2-2, C4-1, C3-2, C5-1, C4-2 and C6-1 are additionally arranged on two sides of the ring network power supply air switches K2, K3, K4 and K5 respectively, so that power monitoring of an alternating current ring network loop and functions of cutting off a fault section alternating current ring network and power backup switching are realized, and corresponding signals of 'alternating current ring network power supply I fault', 'alternating current ring network power supply II fault' and 'alternating current fault' are sent out at a monitoring background by switching on a measurement and control device through normally closed contacts of a voltage intermediate relay ZJ1 and a ZJ2 and normally open contacts of an alternating current contactor C1 and a C2;
when the alternating current ring network power supply loses voltage or a certain section of the ring network power supply is abnormal, the corresponding air switch on the power supply side trips to start the standby power supply switching device, the ring network on the fault section is automatically cut off, the standby power supply on the other side is switched on, meanwhile, a corresponding fault signal is sent out to remind monitoring personnel, and operation and maintenance personnel are informed to check and process in time.
Two voltage intermediate relays ZJ1 and ZJ2 for power supply monitoring, two AC contactors C1 and C2 for automatic switching of two ring network power supplies are additionally arranged in loops at two sides of an AC ring network, a fault occurs at a certain section of the ring network, an auxiliary switch is additionally arranged on ring network power supply air switches K1 and K6 in a standby power supply starting loop-terminal box, an AC contactor C2-1 and C5-2 are additionally arranged at load sides of ring network power supply air switches K1 and K6 respectively, two auxiliary switches are additionally arranged on switches K2, K3, K4 and K5 respectively, and an AC contactor C1-2, C3-1, C2-2, C4-1, C3-2, C5-1, C4-2 and C6-1 are additionally arranged at two sides of ring network power supply air switches K2, K3, K4 and K5 respectively, so that the fault-free ring network power supply can be recovered quickly;
when the voltage of the ring network power supply is lost due to failure, the voltage intermediate relays ZJ1 and ZJ2 are demagnetized, the normally closed contact is closed, the coil loop of the fault-free AC contactor C1 or C2 is connected, and the AC contactor is excited to be used as the standby ring network power supply.
When a certain section of the alternating current looped network is in fault, an air switch K1 or K2 or K3 or K4 or K5 or K6 on the looped network power supply side of the section trips, an auxiliary normally closed contact of the section trips, a coil loop C1-2 or C3-1 or C2-2 or C4-1 or C3-2 or C5-1 or C4-2 or C6-1 of a standby power supply side alternating current contactor of the fault section is switched on, an alternating current contactor of the section is excited, a main normally closed contact opens and cuts off the alternating current looped network of the fault section, a normally open auxiliary contact is switched on, a coil starting loop C1 or C2 of the standby power supply side alternating current contactor is switched on, and a standby power supply side alternating current contactor C1 or C2 of the fault-free looped network.
When any AC looped network power supply loses voltage, the voltage intermediate relays ZJ1 and ZJ2 with power supply monitoring lose magnetism, the normally closed contact is connected with the measurement and control device, and the monitoring background sends out a corresponding AC looped network power supply fault signal.
When a certain section of ring network has a fault, after the fault section of ring network is cut off, the standby ring network power supply AC contactor C1 or C2 is automatically switched on, the AC contactor C1 or C2 on two sides is opened for closing an auxiliary contact, a measurement and control device is switched on, and a monitoring background sends an AC ring network fault signal.
The working principle is as follows:
one, AC power supply one supplies power, AC power supply two is spare
And an AC power supply air switch KK1 and a looped network power supply air switch K1 are switched on.
Alternating current power supply-B phase power supply-alternating current power supply air switch KK 1-voltage intermediate relay ZJ1 starting coil-alternating current power supply-C phase power supply (voltage intermediate relay ZJ1 excitation); the normally open contact of the voltage intermediate relay ZJ1 is closed, and the normally closed contact is opened;
the power supply comprises an alternating current power supply, a C-phase power supply, an alternating current power supply air switch KK1, a looped network power supply air switch K1 normally open contact, an alternating current contactor C1 coil, a voltage intermediate relay ZJ1 normally open contact (at the moment, the voltage intermediate relay ZJ1 is excited, the voltage intermediate relay ZJ1 normally open contact is closed), a voltage intermediate relay ZJ2 normally closed contact, and an alternating current power supply N (the alternating current contactor C1 is excited); the ac contactor C1 has a normally open contact closed and a normally closed contact open.
An alternating current power supply, namely a C-phase power supply, an alternating current power supply air switch KK1, an alternating current contactor C1 coil, a voltage intermediate relay ZJ1 normally-open contact, an alternating current contactor C1 normally-closed contact, and an alternating current power supply N (the alternating current contactor C1 realizes self-holding);
an alternating current power supply I-an alternating current power supply air switch KK 1-an alternating current contactor C1 normally open contact-an air switch K1-an air switch K2 (the air switches K2, K3, K4, K5 and K6 and the alternating current power supply air switch KK2 are sequentially closed);
after an air switch KK2 of the alternating current power supply is closed, a two-phase B power supply of the alternating current power supply is started by a coil of a voltage intermediate relay ZJ2, and a two-phase C power supply of the alternating current power supply is excited by a voltage intermediate relay ZJ 2; and a normally open contact of the voltage intermediate relay ZJ2 is closed, and the automatic switching of the alternating current power supply II is waited.
The second, AC power supply supplies power, the first AC power supply is spare
The principle of switching on the air switch KK2 of the alternating current power supply and the air switch K6 of the ring network power supply is the same as that of supplying power by the first alternating current power supply and supplying power by the second alternating current power supply, but the switching-on sequence of the air switch of the ring network power supply is opposite to that of supplying power by the first alternating current power supply and supplying power by the second alternating current power supply.
Second, ring network power supply K1, K2 short circuit fault between air switches (AC power supply one power supply, AC power supply two spare)
When short-circuit faults occur between ring network power supplies K1 and K2, the ring network power supply K1 air switch trips, an alternating current power supply I-an alternating current power supply air switch KK 1-an alternating current contactor C1 normally-open contact C phase-an ring network power supply air switch K1 normally-closed contact-an alternating current contactor C1-2 coil-an alternating current power supply N, an alternating current contactor C1-2 is excited, and the normally-open contact is closed; the self-holding type AC contactor comprises an AC power supply II, an AC power supply air on-off KK2, a looped network power supply air switch K6 normally open contact, an AC contactor C2 coil, a voltage intermediate relay ZJ2 normally open contact, an AC contactor C1-2 normally open contact, an AC power supply N, an AC contactor C2 normally open contact and an AC power supply two-way automatic switching, and an AC contactor C2 normally open auxiliary contact and an AC contactor C2 self-holding function.
The tripping principle of the air switch of the looped network power supply K2-K5 is the same as that of the air switch.
Three, ring network power K1, K2 short circuit fault between air switch (AC power supply two power supply, AC power supply one standby)
When short-circuit faults occur between ring network power supplies K1 and K2, the ring network power supply K2 air switch trips, an alternating current power supply II, an alternating current power supply air switch KK2, an alternating current contactor C2 normally-open contact C phase, a ring network power supply air switch K2 normally-closed contact, an alternating current contactor C2-1 coil, an alternating current power supply N and an alternating current contactor C2-1 are excited, and the normally-open contact is closed; the self-holding type AC contactor comprises an AC power supply I, an AC power supply air on-off KK1, a looped network power supply air switch K1 normally open contact, an AC contactor C1 coil, a voltage intermediate relay ZJ1 normally open contact, an AC contactor C2-1 normally open contact, an AC power supply N, an AC contactor C1 normally open contact and an AC power supply all the way, wherein the AC contactor C1 normally open auxiliary contact is closed, and the AC contactor C1 is self-held.
The tripping principle of the air switch of the looped network power supply K2-K5 is the same as that of the air switch.
Has the advantages that:
the low-voltage alternating-current ring network loop power supply monitoring and backup switching device is suitable for the technical conditions of the low-voltage alternating-current ring network of the existing transformer substation, and the improvement process is relatively simple.
The low-voltage alternating current looped network loop is additionally provided with the low-voltage alternating current looped network power supply monitoring and standby switching device, so that the cost is low and the expense is low.
The hidden danger is checked and the problem is found early, and the operation guarantee degree of the equipment is optimized.
The inspection amount is relatively reduced, and the management efficiency is enhanced.
The real-time monitoring of the low-voltage alternating-current looped network loop is realized, and the safe and reliable operation coefficient of the equipment and the working efficiency of personnel are improved.