Background technology
Double power supply automatic transfer switch (is called automatic transfer switching electric appliance again; Hereinafter to be referred as ATSE) be mainly used in the two-way electric supply system; Its effect is: when power supply breaks down, load circuit is transformed into another (subsequent use) power supply automatically from (using an always) power supply.
ATSE is as guaranteeing the continuous powered switch electrical equipment of important load, and GB, IEC, UL have formulated corresponding codes and standards (IEC60947-6-1 has issued second edition in August, 2005), and China is also standard progressively at aspects such as design, manufacturing, uses.ATSE has two kinds of ranks of PC level and CB level according to standard, and these characteristics cause the user when selecting, and cause confusion easily.
In CNS, ATSE is divided three classes by short-circuit capacity:
1, PC level: can connect and carry, but be not used in the ATSE of disjunction short circuit current;
2, CB level: be equipped with the ATSE of overcurrent trip, the disjunction short circuit current can connected and be used for to its main contact;
3, CC level: can connect and carry, but be not used in the ATSE of disjunction short circuit current.
Fig. 1 in the accompanying drawing, Fig. 2 and Fig. 3 represent the electrical equipment symbol of these three rank ATSE respectively.
And " Chinese electrical engineering grand ceremony " is divided into the ATSE on the domestic and international market 7 quasi-representative structures again according to architectural feature:
The 1st type: the PC-1 type: the special-purpose PC level ATSE that is operating as characteristic with bistable electro-magnet;
The 2nd type: the PC-2 type: with two switch combinations derivation type PC level ATSE that is characteristic;
The 3rd type: the PC-3 type: to have 3 working positions of two groups of moving contacts is the special-purpose PC level ATSE of characteristic;
The 4th type: the PC-4 type: with single electricity behaviour tape-transport mechanism is the PC level ATSE of the special use of characteristic;
The 5th type: the CB-1 type: by the ATSE of two MCB circuit breakers (miniature circuit breaker) derivation;
The 6th type: the CB-2 type: the ATSE that has two MCCB circuit breakers (breaker of plastic casing) to derive from;
The 7th type: the CB-3 type: by the ATSE of two ACB circuit breakers (omnipotent breaker) derivation.
From using the zone to see, it is main that Europe country adopts CB level ATSE, like the Schneider of German Muller, France; North America (U.S.), East Asia (Japan, Korea S) are main with PC level ATSE; In the product of China, CB level and PC level ATSE are widely used.
See from using, owing to the CC level is made up of two contactors, mechanical interlockings, as easy as rolling off a log melting welding, although cheap, safety does not have to ensure, so mainly ATSE is divided into two big class, i.e. PC level and CB levels in the use at present.Its primary structure is generally:
The PC level is made up of electromagnet operating mechanism and custom-designed change over switch body, controller; The CB level is made up of two circuit breakers, operating mechanism, interlocking device and controllers.
Above data shows, the ATSE classification is so loaded down with trivial details, use and be subjected to regional impact again, and ATSE is divided into the PC level in the Chinese Industrial Standards (CIS), three kinds of CB levels, CC level.The manufacturer is when manufacturing a product; Want several levels ATSE is done entirely very difficulty; The production and processing complicacy is loaded down with trivial details; The production and sales of all kinds of specification ATSE cause social resources to waste in a large number; Also give the very big inconvenience of having used the type selecting band of designing unit and Subscriber Unit, so there is difference in the electrical design personnel to which type of dual-power transfer switch of selection in the circuit always.Above situation shows that present ATSE does not meet product to a certain extent and uses generalization, standardized requirement.
See from the PC level ATSE and the CB level ATSE main distinction:
1, both Machine Design theories are different: the CB level is made up of circuit breaker, and circuit breaker be with breaking arc for appointing, require its mechanical structure to answer rapid-releasing.Thereby there is slide fastener in the mechanism of circuit breaker, buckles problem (promptly buckleing not in place again) again; And there is not this aspect problem in PC level product, and therefore, PC level reliability of products is far above CB level product.
2, both require to have any different to carrying short circuit withstand current: general circuit breaker does not carry the short circuit withstand current, belongs to the category-A circuit breaker more; 400A and above specified shell frame grade circuit breaker have design carrying short circuit withstand current at present, belong to the category-B circuit breaker.It is load circuit when being short-circuited that circuit breaker mainly acts on, when contact is scolded out the generation metering function, thus the disjunction short circuit current; And PC level ATSE should bear 20Ie and above overload current, can carry specified short time withstand current.
3, the selection of contact material requires different: circuit breaker is often selected silver-colored tungsten, the pairing of silver-colored tungsten carbide material, and this helps breaking arc.But such contact material is prone to oxidation, and subsequent use contact long term exposure be prone to form hinders conduction, the difficult oxide of removing outside in its surface, and subsequent use contact is once come into operation, and contact temperature raises, and is prone to cause switch to burn; And PC level ATSE has taken into full account the consequence that the contact material oxidation brings.
4, conversion speed is different: PC level ATSE is a mechanism owing to electromagnet is arranged, and adopts excitation to drive, and conversion speed is fast, generally below 300ms, can be used for the one-level important load; And CB level duplicate supply generally adopts motor as mechanism, and conversion speed is slow, generally more than 1500ms, can only be used for the secondary important load.
Summary of the invention
The problem that the present invention solves provides a kind of double power supply automatic transfer switch; Its objective is and make ATSE become CB level, PC level function integration; Even ATSE possesses specified short circuit breaking capacity and the specified making capacity that opens circuit of CB level, the specified short time withstand current ability of PC level simultaneously, and quick conversion performance and mechanism reliability with PC level.
To achieve these goals, the technical scheme taked of the present invention is:
Double power supply automatic transfer switch provided by the present invention; Be located on the change-over circuit of two-way power supply; Comprise controller, switching mechanism, contact system and arc quenching system; The load circuit of described double power supply automatic transfer switch is provided with the protection type current transformer, and described protection type current transformer is connected with described controller circuitry.
Described protection type current transformer is built-in current transformer; Its mounting means is: establish a cavity before the gusset piece of the load wiring on the change over switch body; The size of this cavity can be put into described built-in current transformer, and described built-in current transformer is fixedly mounted in this cavity.
Described protection type current transformer is the external current transformer, and its mounting means is: described external current transformer is serially connected on the cable of this external load outlet side of change over switch.
Fixed contact in the described contact system is the galvanic circle of U-shaped.
The material of the moving contact in the described contact system is AgW40, and the material of the fixed contact in the described contact system is AgC5.
Perhaps, the material of the moving contact in the described contact system is AgW70, and the material of the fixed contact in the described contact system is AgC5.
Between the contact of the two-way power supply of described contact system, separate through pedestal.
The structure of described arc quenching system is: establish arc quenching plate, following arc quenching plate in the arc control device, between arc quenching plate and the following arc quenching plate, establish the multi-disc arc extinguishing grid pieces on described; The grid sheet fixed head on described arc control device both sides adopts gas exhausted material; The compound flash barrier of two laminated construction is established in the described arc control device outside, and wherein one deck flash barrier in arc control device is provided with a plurality of steam vents, and one deck flash barrier outside arc control device is an elastic piece structure wide at the top and narrow at the bottom.
1.5mm before described fixed contact~2mm place is provided with the striking sheet, and described striking sheet is the structure of bending, and the direction of this bending is that electric arc is introduced described arc control device.
The present invention also provides overload, the short-circuit protection method of above-described double power supply automatic transfer switch, and its goal of the invention is identical with technique scheme, and the step of described guard method is:
1, current sample;
2, A/D digital translation;
3, on controller, show current value, carry out step 4 and step 5 then respectively;
4, whether controller judges current value greater than the overload protection set point, if get into step 6; If, then do not return step 1;
5, whether controller judges current value greater than the short-circuit protection set point, if get into step 6; If, then do not return step 1;
6, switching winding action, double power supply automatic transfer switch are in two branch states;
7, under the condition that meets the double power supply automatic transfer switch operate as normal, through manually or through the combined floodgate button, double power supply automatic transfer switch is devoted oneself to work again, return step 1.
The present invention adopts technique scheme, can realize overload, short-circuit protection function to load, and adjustable, can close; Possess specified short circuit making capacity and specified short circuit breaking capacity; Overload and short-circuit protection can be turned off, just be equal to PC level double power supply automatic transfer switch, so that be applied to the fire-fighting loop; The ability that possesses specified short time withstand current; Embody advantages such as ATSE reliable operation, type selecting be convenient, economic, easy to maintenance; Unification and the generalization of existing all kinds of rank ATSE make things convenient for design, manufacturing and the use of electric power system, practice thrift a large amount of resources.
Embodiment
Contrast accompanying drawing below, through the description to embodiment, specific embodiments of the invention is done further detailed explanation, to help those skilled in the art inventive concept of the present invention, technical scheme is had more complete, accurate and deep understanding.
The of the present invention structure expressed like Fig. 4 to Fig. 9, the present invention is a kind of double power supply automatic transfer switch, is located on the change-over circuit of two-way power supply, comprises base plate 1, controller 2, switching mechanism 3, contact system 6 and arc quenching system.Adopt phase partition 5, phase partition 20 to isolate between each phase.
Its middle controller 2 can also form separately and divide body structures, just be installed on the cabinet body door.
One, have three position mechanisms of three-winding control to carry out brief analysis in the face of controller conventional func and the PC-3 type that relates among the present invention down:
1, the conventional func of controller 2:
Controller 2 is through carrying out voltage and frequency detecting to the two-way power supply; When finding one tunnel (using always) abnormity of power supply (like under-voltage, overvoltage, phase shortage etc.); Automatically be transformed into another road (subsequent use) power supply; When this road (using always) power up just often; Can return operate as normal, this mode is known as " hauling oneself willingly into the runback mode "; If work as this road (using always) power up just often, do not return work, continue to operate in another road (subsequent use) power supply, (subsequent use) abnormity of power supply goes back to and originally (uses) power work always up to this road, and this mode is known as " hauling oneself willingly into not runback mode ".
Above two-way power supply great majority are civil power---the civil power type.If power supply commonly used is a civil power, stand-by power supply is a generator, and then this type is civil power---the generator type is generally the runback mode of hauling oneself willingly into.
2, three position mechanisms of PC-3 type three-winding control:
Drive mechanism so that to have two groups of moving contacts, three working positions be the special-purpose PC-3 type ATSE of characteristic is the basis, and three coils are arranged in this structure:
Closing coil: can allow ATSE be operated in power supply commonly used or stand-by power supply;
When guidance coil: ATSE drops into stand-by power supply must guidance coil and closing coil simultaneously;
Two sub-coils: make ATSE under load overload, short-circuit conditions, jump to centre position (two minutes positions) from power supply commonly used or stand-by power supply.
The three-winding of this structure is contained in switching mechanism 3 inside, can make contact system 6 be in following three kinds of states:
First kind of state is that ATSE is operated in the state when using power supply always: contact system 6 states show that power supply commonly used closes a floodgate this moment as shown in Figure 5 in the mechanism;
Second kind of state is the state of ATSE when being operated in stand-by power supply: when closing coil closes a floodgate and guidance coil moment gets when electric; Square shaft 29 clockwise under switching mechanism drives rotates; Power supply commonly used breaks off; And then square shaft 26 clockwises rotate; Stand-by power supply closes; Be that left side stand-by power supply moving contact 18, fixed contact 21 close among Fig. 5, power supply moving contact 13 is used on the right always, fixed contact was opened in 32 minutes;
The third state is two branch states: when switching winding gets electric the time, under second kind of state, square shaft 29 is motionless, and square shaft 26 inverse clocks rotate; Perhaps first kind of state lower shaft 26 is motionless, and square shaft 29 clockwises rotate, and all makes ATSE be in two branch states, i.e. the state that all breaks off of two-way power supply.
Three working positions are meant: ATSE is operated in position of source commonly used; ATSE is operated in the stand-by power supply position; ATSE is operated in promptly two branch positions, centre position.
When load is transshipped, when short circuit surpasses set point, ATSE jumps to two branch positions automatically;
Have only after unloading or short trouble eliminating, just can rework position of source commonly used or stand-by power supply position.
Two, technical scheme main points of the present invention:
The designing unit of electric power system for ease and consider for the user uses the invention is intended to keep the advantage of PC level, and the advantage of CB level is incorporated the PC level, makes ATSE become the double power supply automatic transfer switch of CB level, PC level function integration.For realizing this goal of the invention, the technical scheme that the present invention takes is:
Like Fig. 4, Fig. 5 and shown in Figure 6, double power supply automatic transfer switch provided by the present invention, the load circuit of described double power supply automatic transfer switch is provided with protection type current transformer 4, and described protection type current transformer 4 is connected with described controller 2 circuit.By 2 pairs of loads of controller transship, short-circuit protection.Described controller 2 is used to receive protection type current transformer 4 and sends current sample; In controller 2, carry out the A/D digital translation; The data that are provided with in back and the controller 2 are carried out the logic comparison; Judge whether greater than overload, short-circuit protection set point and demonstration in real time; Make the switching winding action in case of necessity, action back ATSE is in two branch positions.
Deficiencies all types of to having now, each rank ATSE; The invention provides aforesaid CB level, PC level function integration double power supply automatic transfer switch; It is unified and general that ATSE is realized in the use; Be that ATSE can provide overload, short-circuit protection; The short circuit that possesses the CB level divides short ability and opens circuit making capacity; Satisfy the specified short time withstand current requirement of PC level; Quick conversion performance and mechanism reliability with PC level, thus realize advantages such as ATSE reliable operation, type selecting be convenient, economic, easy to maintenance.
Because ATSE overload, short circuit need current sample, therefore use the protection type current transformer.In fact, be exactly on PC-3 type basic framework, design adds protection type current transformer 4, adds the structure of current sample in the controller 2, to carry out current sample, realizes overload, short-circuit protection function, and overload, short-circuit protection is adjustable, also can close.Its protection type current transformer 4 adopts built-in structure and outlet structure dual mode to fix.
Controller 2 carries out current sample through protection type current transformer 4, carries out the A/D digital translation again, transships, the short-circuit protection logic determines again; If overload current is arranged, just move by the guardtime of requirement in the inverse time lag curve ranges; When if short circuit current surpasses the multiple of rated operational current regulation, the protection action, ATSE jumps to two branch positions; If do not surpass, then continue monitoring current and show.
Three, the form that is provided with of protection type current transformer:
Adopt external and built-in two kinds of structures, soon protection type current transformer 4 is gone here and there on load wiring and is installed in the two kinds of structures in body the inside, also will on conventional ATSE intelligent controller, increase overload, short-circuit protection function in addition.
Described built-in structure: will before the gusset piece in load wiring on the change over switch body, design the built-in space that to put into the protection type current transformer exactly, to satisfy current sample.
Above-described protection type current transformer 4 is built-in current transformer 16; Its mounting means is: establish a cavity before the gusset piece 17 of the load wiring on the change over switch body; The size of this cavity can be put into described built-in current transformer 16, and described built-in current transformer 16 is fixedly mounted in this cavity.
The A-A that is Fig. 4 as shown in Figure 5 embodies arc quenching system structure and the built-in structure of protection type current transformer to profile.
The design of protection type current transformer embedding structure mainly contains contact plate 15, soft connection 14, gusset piece 17, protection type current transformer 16, lead-in wire groove 9, current transformer lead-in wire 7 formations in the load outlet.The output of protection type current transformer 16 is connected with controller (2) through protection type current transformer lead-in wire 7; One side is very big owing to the protection type current mutual inductor coil takes up space, Gu will be designed to soft connection 14 modes between contact plate 15 and the gusset piece 17.Being flexible coupling 14 also can be designed to the cylinder mode, between riveted joint contact plate 15 and the gusset piece 17, before riveted joint, puts protection type current transformer 16 earlier; Gusset piece 17 is load outlets on the other hand, no matter which power supply ATSE is operated in, the load outlet all is public, and ATSE only needs 3 protection type current transformers just can accomplish current sample like this.
Described outlet structure: be exactly with protection type current transformer string in change over switch body load outlet side, be enclosed within on the cable 34 by the user, to satisfy current sample.
Described protection type current transformer 4 is an external current transformer 33, and its mounting means is: described external current transformer 33 is serially connected on the cable of this external load outlet side of change over switch.
What Fig. 6 represented is ATSE protection type current transformer outlet structure, is enclosed within on the cable 34 through external protection type current transformer 33 and realizes.
Built-in structure is that special space is set on the pedestal of ATSE load end, with built-in protection type current transformer, and the protection type instrument transformer is carried out size design, makes it can be contained in the load end of pedestal; Outlet structure is directly to be enclosed within load outlet side, and protection type current transformer lead-in wire access controller is got final product.
Four, the design of arc quenching system:
Because the ATSE among the present invention possesses specified short circuit breaking capacity; Therefore need redesign arc quenching system; Make ATSE that overload, short-circuit protection can be provided, possess the short circuit breaking capacity and the short circuit making capacity of CB level, possess the specified short time withstand current requirement of PC level.Contact system is redesigned, make product possess certain short circuit breaking and making capacity, and possess short time withstand current, in short circuit breaking, ATSE can jump to two branch positions, and load this moment is all broken off with normal, stand-by power supply.
Described arc quenching system redesign comprises that contact system, slider material are selected, the arc control device design.
1, the fixed contact 21 in the described contact system 6, fixed contact 32 are the galvanic circle of U-shaped.When contact system designs, fixed contact is made the U-shaped galvanic circle, strengthen magnetic field and act on the electrodynamic repulsion force on the moving contact.
When the loop of the fixed contact 21 (or fixed contact 32) of short circuit current through U-shaped and moving contact 18 (or moving contact 13); By locating Huo Muli between parallel conductor generation electrodynamic repulsion force and moving contact 25 (or moving contact 30) and the fixed contact 27 (or fixed contact 12); Moving contact 18 (or moving contact 13) is opened fast, produced arc voltage and current limliting.The fixed contact 21 of U-shaped (or fixed contact 32) is when design, and the contact-making surface that connects inlet wire is higher than fixed contact 27 (or fixed contact 12) face, and fixed contact generates an electromagnetic field and can quicken extinguish arcs like this.
2, slider material is selected:
Specified shell frame grading current 400A and following dynamic and static slider material adopt AgW40 and AgC5 pairing respectively; Be that the moving contact 25 in the described contact system 6, the material of moving contact 30 are AgW40, the fixed contact 12 in the described contact system 6, the material of fixed contact 27 are AgC5.
Specified shell frame grading current 400A and above dynamic and static slider material adopt AgW70 and AgC5 pairing respectively; Be that the moving contact 25 in the described contact system 6, the material of moving contact 30 are AgW70, the fixed contact 12 in the described contact system 6, the material of fixed contact 27 are AgC5.
For guaranteeing good connection interrupting performance, moving contact 25 (moving contact 30) adopts AgW70 at rated operational current 400A and following employing AgW40 more than the 400A; Fixed contact 27 (fixed contact 12) all adopts AgC5.
Silver tungsten (AgW40, AgW70) electrical contact material extreme hardness; Good resistance to wear and stability; Anti-arcing is good, scaling loss is few, welding tendency is little; And silver-colored graphite 5 (AgC5) electrical contact material has good resistance fusion welding and conductivity, low and stable contact resistance and excellent low temperature rise characteristic; Matrix silver provides good conductivity and don't has formed stable oxide, thereby can not cause the rapid rising of contact resistance in use.
Contact system redesign with PC level double power supply automatic transfer switch makes ATSE not only possess short time withstand current and specified short circuit making capacity, and possesses specified short circuit breaking capacity, improves the short-circuit protection performance of ATSE.
3, the isolation of arc control device:
Like Fig. 5 and shown in Figure 6, between the contact of the two-way power supply of described contact system 6, separate through pedestal 28.
When arc control device design, adopt power supply commonly used and the complete isolation method of stand-by power supply arc extinguishing, when preventing one road power work, during because of the load short circuits disjunction, the electric arc influence of generation prevents the electric arc re-breakdown phenomenon to another road power supply.Power supply commonly used and stand-by power supply arc quenching system form symmetry, and the centre has pedestal 28 completion to separate, and power supply commonly used, stand-by power supply close, timesharing is independent of each other each other.
4, the structure of described arc quenching system is:
Represent the structure of arc control device like Fig. 7, establish arc quenching plate 36, arc quenching plate 38 down in arc control device 11, the arc control device 24 respectively, between arc quenching plate 36 and the following arc quenching plate 38, establish multi-disc arc extinguishing grid pieces 37 on described; Described arc quenching plate 36, following arc quenching plate 38 and the arc extinguishing grid pieces 37 gone up all used cold-rolled steel sheet Q235, plating nickel on surface.
When short circuit breaking; Electric arc is drawn back in electric arc quick disjunction under the switching winding effect of switching mechanism 3; Utilize last arc quenching plate 36, arc extinguishing grid pieces 37, following arc quenching plate 38 in the arc control device will elongate electric arc and be cut into several sections short arcs rapidly, and in arc control device 11 and arc control device 24, cool simultaneously.Arc extinguishing grid pieces 37 is cut into short arc with long arc, not only plays the effect of grid sheet arc extinguishing, and electric arc is cooled off rapidly.
The grid sheet fixed head 35 on described arc control device 11, arc control device 24 both sides adopts gas exhausted materials.The gas exhausted material that the grid sheet fixed head 35 of arc control device adopts is an advanced melamine glass fabric laminate.Arc control device 11, arc control device 24 both sides flash barriers 35 adopt gas exhausted material, help the effect of air-blowing arc.
Fig. 8 representes the part drawing of flash barrier 10, flash barrier 23; Fig. 9 representes flash barrier 8, flash barrier 22) part drawing.
The compound flash barrier of two laminated construction is established in the outside of described arc control device 11, arc control device 24 respectively; Wherein one deck flash barrier 10 in arc control device, flash barrier 23 are provided with a plurality of steam vents, and one deck flash barrier 8 outside arc control device, flash barrier 22 are elastic piece structure wide at the top and narrow at the bottom.
Flash barrier 10, have steam vent above the flash barrier 23, it is free from cut-offfing to arc control device to help electric arc, forms the effect of air-blowing arc; Flash barrier 8, narrow down face width above flash barrier 22 parts, when exhaust, the first half is crooked and open to outwash by air-flow; When arc extinguishing finished, the first half was recovered under elastic reaction own.
The flash barrier that arc control device 11, arc control device 24 are arranged is grid sheet fixed head 35 aerogenesis, and breaks off under the huge air pressure of moment at electric current, through flash barrier 10 and flash barrier 8, flash barrier 22 and flash barrier 23 exhausts, plays the effect of air-blowing arc, and electric arc is extinguished rapidly.
In the flash barrier 10 of arc quenching system inner face, the advanced melamine glass fabric laminate that flash barrier 23 adopts the band steam vent; Flash barrier 8, the flash barrier 22 of arc quenching system outside are the hard steel cardboard.
Last arc quenching plate 36, arc quenching plate 38 not only can play breaking arc down, can also stop electric arc diffusion up and down outside arc control device.
1.5mm~2mm place is provided with striking sheet 19, striking sheet 31 respectively before described fixed contact 12, fixed contact 27, and described striking sheet 19, striking sheet 31 are the structure of bending, and the direction of this bending is that electric arc is introduced described arc control device (11,24).
Run-on tab adopts cold-rolled steel sheet Q235, plating nickel on surface.1.5 arrive 2mm place design striking sheet 19 and striking sheet 31 before fixed contact, play the effect of electric arc being introduced arc control device 24 and arc control device 11.
Arc quenching system adopts above structure can improve specified short circuit breaking capacity and specified short circuit making capacity greatly, also satisfies overload, short-circuit protection requirement.
Five, owing to adopt said structure and design, the present invention is had the following advantages;
1, can realize overload, short-circuit protection function to load, and adjustable, can close;
2, possess specified short circuit making capacity and specified short circuit breaking capacity;
3, overload and short-circuit protection can be turned off, just be equal to PC level double power supply automatic transfer switch, for use in the fire-fighting loop.
4, possesses specified short time withstand current.
5, make unitized, the generalization of all kinds of rank ATSE, a large amount of conservation of power and social resources.
Six, the guard method of overload, short circuit:
The present invention also provides overload, the short-circuit protection method of above-described double power supply automatic transfer switch, and its goal of the invention is identical with technique scheme.
On the controller that possesses conventional ATSE function, add the electric current sampling; Carry out the A/D digital translation earlier; Transship again, the short-circuit protection logic determines; If overload current is arranged; Just the guardtime by requirement in the inverse time lag curve ranges moves; When if short circuit current surpasses the multiple (the short circuit set point is 1.0Ie-20.0Ie, and is adjustable) of rated operational current regulation, the protection action makes ATSE jump to two branch positions; If do not surpass the multiple of rated operational current regulation, then continue monitoring current numerical value.
The step of described guard method is:
1, current sample;
2, A/D digital translation;
3, on controller 2, show current value, carry out step 4 and step 5 then respectively;
4, whether controller 2 judges current value greater than the overload protection set point, if get into step 6; If, then do not return step 1;
5, whether controller 2 judges current value greater than the short-circuit protection set point, if get into step 6; If, then do not return step 1;
6, switching winding action, double power supply automatic transfer switch are in two branch states;
7, under the condition that meets the double power supply automatic transfer switch operate as normal, through manually or through the combined floodgate button, double power supply automatic transfer switch is devoted oneself to work again, return step 1.
Figure 10 is the overload of ATSE, the FB(flow block) of short-circuit protection; Step 1 is carried out current sample through protection type current transformer 4; Step 2 is carried out the A/D conversion through the electric current microprocessor in the controller 2; Step 3 shows current value on controller 2; Step 4 and step 5 judge that respectively whether the demonstration current value is greater than overload and short-circuit protection set point; If not, then return the sampling of step 1 intermittent current; If, then getting into the action of step 6 switching winding, after the action, ATSE jumps to two branch positions.
After unloading or short trouble eliminating, manually or through combined floodgate button (power supply commonly used or stand-by power supply combined floodgate button) ATSE is devoted oneself to work again.
Described overload, the short-circuit protection set point is all adjustable and can close.Described closing is meant, when not needing overload protection, can close and plant protection; When not transshipping and short-circuit protection, overload and short-circuit protection all can be closed.
When overload protection is closed, no step 4 among Figure 10, when overload, when short-circuit protection is all closed, among the figure in steps 1, step 2 and step 3.
Combine accompanying drawing that the present invention has been carried out exemplary description above; Obviously the concrete realization of the present invention is not subjected to the restriction of aforesaid way; As long as adopted the improvement of the various unsubstantialities that method of the present invention design and technical scheme carry out; Or design of the present invention and technical scheme are directly applied to other occasion without improving, all within protection scope of the present invention.