CN101917058B

CN101917058B - Method and system for switching backup power supply

Info

Publication number: CN101917058B
Application number: CN2010102652374A
Authority: CN
Inventors: 梁俊滔; 陈曙玲
Original assignee: SHENZHEN GUOLIZHENG ELECTRIC POWER TECHNOLOGY Co Ltd
Current assignee: SHENZHEN GUOLIZHENG ELECTRIC POWER TECHNOLOGY Co Ltd
Priority date: 2010-08-26
Filing date: 2010-08-26
Publication date: 2013-05-01
Anticipated expiration: 2030-08-26
Also published as: CN101917058A

Abstract

The invention relates to a method and a system for switching a backup power supply. The method comprises the following steps of: starting switching and tripping off a working power switch; acquiring the operation condition of the backup power supply; and if a condition is accordant with the tripping off criterion of the working power switch and the operation condition of the backup power supply, performing a power supply switching action and putting the backup power supply into operation, wherein the execution of the starting switching and the stripping off of the working power switch comprises one or more of the following criteria: frequency voltage quality starting, frequency difference starting, frequency difference non-current starting, reverse power starting and frequency difference reverse power starting. At least one of five criteria is adopted, so that the power supply can be switched rapidly and correctly. Moreover, a multi-judgment backup power supply operation condition is adopted, so that the backup power supply can be put into operation correctly and the backup power supply is switched rapidly and correctly and put into operation.

Description

Stand-by power supply changing method and system

[technical field]

The present invention relates to power domain, particularly relate to a kind of stand-by power supply changing method and system.

[background technology]

In factories and miness consecutive production enterprises such as petrochemical industry, metallurgy, its production technology and flow process have proposed very high requirement to power supply reliability and continuity, and the interruption of power supply and voltage fluctuation can be brought huge loss to enterprise.

Such as Fig. 1, according to the n-1 criterion of conventional electric power system, in order to improve power supply reliability, the electric power system of above-mentioned industrial enterprise all adopts and is no less than two power supply designs.Two inlet wires are powered to bus simultaneously, and bus connection switch ML disconnects, and I bus and II bus be stand-by power supply each other.Article two, inlet wire derives from the different substation of same electrical network, when electrical network breaks down when causing wherein one section bus (I bus or II bus) dead electricity, the service entrance switch of tripping dead electricity bus (1DL or 2DL), then mother ML is closed at once, make the dead electricity bus again be subjected to electricity, improve power supply reliability with this.The device that electric power system will be used for finishing these a series of power supply switching controls is referred to as automatic throw-in equipment of emergency power supply, is called for short prepared auto restart.

Because the difference of part throttle characteristics and operating condition, the input condition of traditional prepared auto restart has three kinds usually, and namely 1. working power disconnects (using " without stream " to make criterion); 2. backup power source voltage normally (is used " pressure is arranged " criterion); 3. the busbar voltage of loading is zero (using " with no pressure " criterion).But 3. condition has significant limitation, because the main load of industrial enterprise is various motor, motor cluster will enter the generator state after the bus dead electricity, and its feedback voltage has consisted of the residual voltage (such as Fig. 2) of dead electricity bus; After bus with a large amount of induction-motor loads loses power supply, particularly has the synchronous motor in independent excitation loop, its voltage V _MFrequency and amplitude in fact reflected remaining meritorious (machinery inertial) and idle (magnetization energy) component of motor cluster, often need the several seconds just can decay to zero.According to condition 3. drop into stand-by power supply, to cause long interruption duration, again being subjected to needs the long dynamo-electric transient process (several seconds) of elapsed-time standards behind the electricity, moreover this moment for fear of a large amount of in groups self starting motors to the impact of stand-by power supply, generally need the cut-out load branch circuit, this has brought huge economic loss for equicontinuity manufacturing enterprise.

In addition, the load condition of industrial enterprise is complicated, and a lot of large-scale factories and miness have configured house generator.When the bus dead electricity, house generator is owing to having independently energized circuit and dynamical system, and they all have stronger supporting role to the power in the loading zone and voltage consumption, so that existing stand-by power supply can't in time switch, put into production use timely.

[summary of the invention]

Based on this, be necessary to provide fast changing method of a kind of stand-by power supply.

In addition, also be necessary to provide fast switched system of a kind of stand-by power supply.

A kind of stand-by power supply changing method may further comprise the steps:

Start and switch tripping working power switch; Gather the in-put of spare power supply condition; The criterion and the in-put of spare power supply condition that meet the tripping of described working power switch are then carried out the Switching power action, drop into stand-by power supply; Described reaching starts switching, and the execution of tripping working power switch comprises a kind of of following criterion at least, and described criterion has: press quality startup, frequency difference startup, frequency difference to start and the startup of frequency difference inverse probability without stream startup, inverse probability frequently;

Described frequency presses the condition of quality start-up criterion to be: (U _n-U _Ab)＞Δ U _p, (U _n-U _Bc)＞Δ U _p, (U _n-U _Ca)＞Δ U _p, (F _n-F _Bus)＞Δ F _p, dF/dt＞50Hz/s, above-mentioned condition must satisfy simultaneously, by the action delay t that sets _Dz1, described frequency is pressed quality to start and is then carried out and starts action; U wherein _nAnd F _nThe rated voltage and the rated frequency that refer to respectively load system; U _Ab, U _Bc, U _CaRefer to the three-route voltage of dead electricity bus; F _BusRefer to the frequency of bus; Δ U _pWith Δ F _pRefer to respectively the voltage deviation and the frequency departure that allow come value according to the situation of grid supply quality, preferably voltage deviation is 10～15%U _nWith frequency departure be 0.2～0.5Hz; DF/dt refers to frequency slip frequency; t _Dz1Represent action delay;

The condition of described frequency difference start-up criterion is: F _Bus＜F _n, (F _b-F _Bus)＞Δ F _Dz, U _Bus＞U _Dy, above-mentioned condition must satisfy simultaneously, by the action delay t that sets _Dz2, described frequency difference starts then to carry out to start moves; U wherein _BusIt is the busbar voltage of frequency measurement; F _BusRefer to the frequency of bus; F _bRefer to the frequency of stand-by power supply; Δ F _DzRefer to the operating value that frequency difference is out-of-limit; U _DyIt is the low-voltage dead lock value of described frequency difference start-up criterion; t _Dz2Represent action delay;

Described frequency difference without the condition of stream start-up criterion is: F _Bus＜F _n, (F _b-F _Bus)＞Δ F _Dz, U _Bus＞U _Dy, I _a＜I _Wl, I _b＜I _Wl, I _c＜I _WlAbove-mentioned condition must satisfy simultaneously, by the action delay t that sets _Dz3, described frequency difference starts then to carry out to start without stream moves; U wherein _BusIt is the busbar voltage of frequency measurement; F _BusRefer to the frequency of bus; F _bRefer to the frequency of stand-by power supply; Δ F _DzRefer to the operating value that frequency difference is out-of-limit; U _DyThat described frequency difference is without the low-voltage dead lock value of stream start-up criterion; I _a, I _b, I _cRefer to the three-phase current of working power inlet wire; I _WlRefer to for the definite value of differentiating without stream; t _Dz3Represent action delay;

The condition of described inverse probability start-up criterion is: A phase power direction is for flowing out bus, and B phase power direction is for flowing out bus, and C phase power direction is for flowing out bus, I _a＞I _Set, I _b＞I _Set, I _c＞I _SetAbove-mentioned A phase power direction is that outflow bus, B phase power direction are at least one establishment among the outflow bus condition for outflow bus, C phase power direction, and I _a＞I _Set, I _b＞I _Set, I _c＞I _SetAmong at least one set up and the action delay t by setting _Dz4, described inverse probability starts then to carry out to start moves; Wherein, I _a, I _b, I _cRefer to the three-phase current of working power inlet wire; I _SetRefer to the starting current value that inverse probability is differentiated; t _Dz4Represent action delay;

The condition of described frequency difference inverse probability start-up criterion is: A phase power direction is for flowing out bus, and B phase power direction is for flowing out bus, and C phase power direction is for flowing out bus; I _a＞I _Set, I _b＞I _Set, I _c＞I _SetF _Bus＜F _n, (F _b-F _Bus)＞Δ F _Dz, U _Bus＞U _DyAbove-mentioned A phase power direction is that outflow bus, B phase power direction are at least one establishment among the outflow bus condition, I for outflow bus, C phase power direction _a＞I _Set, I _b＞I _Set, I _c＞I _SetAmong at least one set up and F _Bus＜F _n, (F _b-F _Bus)＞Δ F _Dz, U _Bus＞U _DyAll set up, and the action delay t by setting _Dz5, described frequency difference inverse probability starts then to carry out to start moves; I _a, I _b, I _cRefer to the three-phase current of working power inlet wire; I _SetRefer to the starting current value that inverse probability is differentiated; t _Dz5Represent action delay.。

Preferably, described startup is switched, and the step of tripping working power switch also comprises the criterion of power direction locking.

Preferably, described startup is switched, and the step of tripping working power switch also comprises U _Bus＜30%U _nCriterion and/or F _BusThe criterion of＜40Hz; Described U _BusIt is the busbar voltage of frequency measurement; Described U _nIt is the rated voltage of load system; Described F _BusRefer to the frequency of bus.

Preferably, described startup is switched, and the step of tripping working power switch also comprises the normal criterion of stand-by power supply.

Preferably, described collection in-put of spare power supply condition comprises:

Step S210, the bus dead electricity;

Step S220 judges whether frequency difference pressure reduction is out-of-limit, is the step S270 that then enters with no pressure prepared auto restart logic, judges whether house generator withdraws from the step S230 of load system otherwise change over to;

Step S230 judges whether house generator withdraws from load system, is then to enter to judge whether synchronous motor withdraws from the step S240 of load system, otherwise enters the step S231 that judges whether to satisfy the simultaneous interconnecting condition; The described step S231 that judges whether to satisfy the simultaneous interconnecting condition is then to drop into stand-by power supply S260, otherwise returns step S220;

Step S240 judges whether synchronous motor withdraws from load system, is then to enter to judge whether to satisfy the step that the asynchronous electric power supply drops into criterion S250, judges whether to satisfy the step S241 that the synchronous motor power supply drops into criterion otherwise enter; Described judging whether satisfied the step S241 that the synchronous motor power supply drops into criterion, is then to drop into stand-by power supply S260, otherwise returns step S220;

Step S250 judges whether to satisfy the asynchronous electric power supply and drops into criterion, is then to drop into stand-by power supply S260, otherwise returns step S220.

Preferably, describedly meet the criterion of described working power switch tripping and the condition of in-put of spare power supply condition also comprises: the normal criterion of stand-by power supply.

Preferably, describedly meet the criterion of described working power switch tripping and the condition of in-put of spare power supply condition also comprises: the criterion of unbalance voltage locking.

A kind of stand-by power supply switched system also is provided simultaneously, comprises: processing module, the synchronized sampling module that is connected with processing module, open into acquisition module and leave control module; The synchronized sampling module is used for gathering electric current, voltage and frequency values; Open into acquisition module, be used for to gather and to open into signal, the described signal of opening comprises at least a in circuit breaker auxiliary contact position signalling, relay protection signal and the control switch signal; Processing module, for the electric current, voltage and the frequency values that gather according to described synchronized sampling module, and open into opening into signal that acquisition module gathers, judge by criterion and in-put of spare power supply condition to the tripping of working power switch, send control signal; The criterion of described working power switch tripping comprise frequently press that quality starts, frequency difference starts, frequency difference without stream start, inverse probability starts, at least a in starting of frequency difference inverse probability; Leave control module, the control signal that is used for sending according to processing module is carried out control action;

Preferably, also comprise: what be connected with processing module leaves signaling module, is used for the control signal that the Graphics Processing module produces; The gps clock module that is connected with processing module is for the clock information of correcting the stand-by power supply switched system.

Preferably, also comprise: the human-computer interaction module that is connected with processing module, the operating state that is used for setting the numerical value of relevant criterion and/or feeds back the stand-by power supply switched system; The communication module that is connected with processing module is used for signal transmission, far distance controlled and understands described stand-by power supply switched system; The printer module that is connected with processing module is for the parameter of printing the stand-by power supply switched system; The power module that is connected with processing module is used to the stand-by power supply switched system that DC power supply is provided.

Adopt at least a among 5 kinds of criterions, Switching power fast and accurately, and adopt the in-put of spare power supply conditions of judging can drop into stand-by power supply accurately, reaches to switch fast and accurately and drop into stand-by power supply.

Further, also comprise 2 analog quantity locking criterions, can drop into more accurately and rapidly stand-by power supply.

[description of drawings]

Fig. 1 is conventional electric power system power supply mode schematic diagram;

Fig. 2 is the polar diagram of the relative stand-by power supply of dead electricity bus residual voltage;

Fig. 3 is the transient analysis model of stand-by power supply and motor equivalent circuit;

Fig. 4 is the flow chart of stand-by power supply changing method;

Fig. 5 is for starting the logic diagram of tripping working power switch;

Fig. 6 is for frequently pressing quality enable logic figure;

Fig. 7 is frequency difference enable logic figure;

Fig. 8 is that frequency difference is without stream enable logic figure;

Fig. 9 is inverse probability enable logic figure;

Figure 10 is frequency difference inverse probability enable logic figure;

Figure 11 is power direction latching logic figure;

Figure 12 is in-put of spare power supply control logic figure;

Figure 13 is for dropping into the logic diagram of stand-by power supply;

Figure 14 is unbalance voltage latching logic figure;

Figure 15 is the theory diagram of stand-by power supply switched system.

[embodiment]

The problem that can't in time switch in order to solve stand-by power supply provides a kind of in-put of spare power supply condition and quick stand-by power supply fast switch over method that starts of stand-by power supply followed.

For power load, should before declining to a great extent, rotating speed and busbar voltage drop into stand-by power supply, when namely the amplitude of dead electricity bus residual voltage (the synthetic feedback voltage of numerous motor, be commonly called as be residual voltage) and frequency are also high, by seeking the timing input of stand-by power supply, drop into stand-by power supply.Because motor speed and the output torque of power load are still higher, the impact of in-put of spare power supply moment is little, dynamo-electric transit time after the input short (hundreds of millisecond), make whole or most power loads in the situation that there is not obvious disturbance again to be subjected to electricity.

After the motor dead electricity, the input current vanishing of motor cluster, rotor current is decayed gradually because machinery inertial, rotor speed will be slowed down gradually from the amount value, rotor current magnetic field will be in stator winding the reverse induction electromotive force, form feedback voltage.When multiple motors is linked in same bus, because the situations such as each capacity motor, load are different, in the coasting process, the partial asynchronous motor will be the asynchronous generator feature, and other are the asynchronous motor feature.As shown in Figure 3, the transient analysis model of stand-by power supply and motor equivalent circuit is ignored motor winding resistance, excitation impedance etc., And X _MThe expression load system is equivalent electromotive force and the equivalent reactance of motor cluster;

And X _BEquivalent electromotive force and the equivalent reactance of expression standby power system; Δ V is two voltage differences between the system, and Δ θ is two merit angles between the system.

In suitable, drop into stand-by power supply, need to discuss two kinds of situations: the one, the impact that the input stand-by power supply brings must be in the tolerance range of electrical network; The 2nd, whether can damage the rotating machinerys such as motor and generator.

For the impact to electrical network, mainly comprise two parts: steady-state component and the transient state of the moment of closing a floodgate are impacted.Steady-state component is because power load impacts the distribution of electric network active, reactive power flow from the work branch transition to candidate branch; This impact belongs to that electrical network itself determines, and present electrical network scale is larger, substantially can not have this problem.The transient state of moment of closing a floodgate is impacted, and the unusual service conditions such as electric parameters Changing Pattern that can be from the stand-by power supply handoff procedure and the fault that is short-circuited are compared, and just can make an assessment to its impact.Wherein, the impulse current I during in-put of spare power supply _mThrough type 1 obtains short circuit current I during dead electricity bus three-phase shortcircuit _dThrough type 2 obtains.Because load equivalent impedance X _MStand-by power supply impedance X much larger than twice _B, and

So I _mMuch smaller than I _dAs for the start-up time of impacting, because motor speed is still very high, the moment of friction of load does not obviously increase, thus after several cycles, will again be pulled near rated speed, thus impulse current is obviously descended, dynamo-electric transient process is very short.Therefore drop into fast stand-by power supply to the disturbance of electrical network in the acceptable scope.

I_{m} = \frac{ΔV}{X_{B} + X_{M}} < \frac{2 | {\overset{\cdot}{V}}_{B} |}{{2 X}_{B}}

(formula 1)

I_{d} = \frac{| {\overset{\cdot}{V}}_{B} |}{X_{B}}

(formula 2)

For rotating machinerys such as motor and generators, namely to the analysis of power load.In-put of spare power supply moment, the impact that motor bears can be divided into meritorious and idle component.Meritorious to impact major embodiment be the impact that motor rotary shaft bears, and the moment size of impact determines by merit angle Δ θ, and the duration is determined by frequency difference Δ f, and reactive power impact is determined by the amplitude of Δ V.Now the control interval of various motors is analyzed:

(1) for the load system that asynchronous motor is arranged, owing to itself just operating in asynchronous operating mode, and self there is not field power supply, so its interval that can drop into stand-by power supply is wider, concrete have following several factor:

The amplitude of in-put of spare power supply moment Δ V is too high, can the insulation of motor stator winding be caused damage.Because bus residual voltage

Amplitude be constantly to descend, so only however With

Drop into stand-by power supply when anti-phase, the amplitude of Δ V just can be controlled.

In-put of spare power supply moment angular difference Δ θ can not be too large, otherwise motor institute bringing onto load will make machine shaft bear the moment of torsion of the definite value that far exceeds the quata, when Δ θ＞90 ° because rotor induction gesture and stator field are reverse, the transient acceleration that load obtains will be how much with angular difference Δ θ increase to be increased, so that machine shaft sustains damage, so the angular difference Δ θ that drops into moment should be controlled in 90 °; Consider the error of control, it is 80 ° that input angular difference Δ θ preferably is controlled at the engineering objective value.

During in-put of spare power supply, the rotating speed of motor can not be too low, the lower dynamo-electric process of rotating speed is longer, self-starting current is larger, the large-sized asynchronous motor of the special Starting mode of other needs can't be finished even from opening process and reenter nominal situation, cause uninterruptedly again being subjected to the electricity failure, should require more than 80% rated speed for most scenes, namely in the frequency difference Δ f 10Hz.

During in-put of spare power supply, the residual voltage of bus can not be too low, because the exciting current of asynchronous motor rotor comes by induction stator alternating magnetic field, when the bus residual voltage is too low, show that the large section of its exciting current decays, be subjected to again to obtain behind the electricity specified torque consuming time partially long; The measurement to frequency and phase angle when moreover the bus residual voltage is too low also is disadvantageous, can affect the precision of control.

(2) for the load system that synchronous motor is arranged, in order to ensure can be with its pull-in step behind the in-put of spare power supply, frequency difference Δ f and the angular difference Δ θ that drops into moment all there is more sternly requirement: at first, the frequency difference Δ f that drops into moment must be less than 5Hz, bus port residual voltage is greater than 60%, otherwise need to be with itself and bus disconnection before dropping into stand-by power supply; Secondly, different to the requirement that drops into angular difference Δ θ when frequency difference is in different size, for the ease of engineering construction, delimit the control area by formula 3 and formula 4.

During Δ f＜1Hz, Δ θ＜65 ° (formula 3)

During 5Hz＞Δ f＞1Hz, Δ θ＜30 ° (formula 4)

(3) for the load system that house generator is arranged, in fact the process of in-put of spare power supply is equal to the process that two off-the-line systems are incorporated into the power networks again, because underfrequency can be damaged the dynamical system of generator, so the generator compulsory withdrawal is moved during greater than 3Hz as frequency difference Δ f; When frequency difference Δ f is less than or equal to 3Hz, drop into stand-by power supply according to difference frequency simultaneous interconnecting principle during near 0 ° at angular difference Δ θ.

By reference to the accompanying drawings 4, based on above-mentioned technological thought, the stand-by power supply changing method is proposed, "+" expression "or" in the accompanying drawing, “ ﹠amp; " expression " with ".Concrete grammar may further comprise the steps:

S100 starts and switches tripping working power switch.By reference to the accompanying drawings 5, particularly, reach startup and switch the quick execution of tripping working power switch, at least comprise and comprise one or more of following criterion: press that quality starts, frequency difference starts frequently, frequency difference without stream start, inverse probability starts and the frequency difference inverse probability starts.

Frequently press quality to start, by reference to the accompanying drawings 6, press criterion that quality starts to determine whether dead electricity of bus by the electric power thus supplied that detects bus frequently.Particularly, in the corresponding active power of AC system medium frequency, the corresponding reactive power of voltage, when only having both all qualified, electric power thus supplied is only normally.(electric power system or generating equipment are because protection or automatic safety device action or requirement in accordance with regulations as long as off-the-line does not occur electrical network; untie and interconnect the operation that makes its isolated operation); the frequency of system is unique, and is therefore far better than sensitivity and the selectivity of traditional low voltage starting.Mainly be during all greater than permissible variation, then to start switching by frequency departure (rated frequency deducts practical frequency, be called for short frequency difference) and voltage deviation (rated voltage deducts actual measurement voltage, is called for short pressure reduction).

Particularly, this presses the condition of quality start-up criterion to be frequently: (U _n-U _Ab)＞Δ U _p, (U _n-U _Bc)＞Δ U _p, (U _n-U _Ca)＞Δ U _p, (F _n-F _Bus)＞Δ Fp, dF/dt＞50Hz/s (this condition is " non-" in logic diagram, negate), above-mentioned condition must satisfy simultaneously, by the action delay t that sets _Dz1, this is frequently pressed quality to start and then carries out and starts action.U wherein _nAnd F _nThe rated voltage and the rated frequency that refer to respectively load system; U _Ab, U _Bc, U _CaRefer to the three-route voltage of dead electricity bus; F _BusRefer to the frequency of bus; Δ U _pWith Δ F _pRefer to respectively the voltage deviation and the frequency departure that allow come value according to the situation of grid supply quality, preferably voltage deviation is 10～15%U _nWith frequency departure be 0.2～0.5Hz; DF/dt refers to frequency slip frequency, i.e. rate of change is preferably and is less than or equal to 50Hz/S, because frequency reflection machinery inertial, descending represents measuring error or load system collapses too soon; t _Dz1Represent action delay, preferably get 50～100ms.

Frequency difference starts, and by reference to the accompanying drawings 7, the criterion that frequency difference starts is determined whether dead electricity of bus by relatively bus frequency and stand-by power supply frequency.Particularly, for most of quantity-produced enterprise, two stand-by power supplies derive from same electrical network, so the frequency of two stand-by power supplies is identical when normally moving; Even if electric network fault causes in short-term rolling electricity (rolling electricity refer to line voltage is instantaneous fall and recover normal phenomenon), only otherwise cause off-the-line, the frequency of two stand-by power supplies is still identical; Only behind grid disconnection, namely lose power supply fully after, cause the motor speed of load system to descend and just can start.Account for the load system of larger specific gravity at synchronous motor and house generator, voltage drop is very slow after the dead electricity, and this frequency difference start-up criterion still can guarantee to start reliably action.

Particularly, the condition of this frequency difference start-up criterion is: F _Bus＜F _n, (F _b-F _Bus)＞Δ F _Dz, U _Bus＞U _Dy, above-mentioned condition must satisfy simultaneously, by the action delay t that sets _Dz2, this frequency difference starts then to carry out to start moves.U wherein _BusThe busbar voltage (U of frequency measurement _BusRefer to the current voltage that is judged to the dead electricity bus); F _BusRefer to the frequency of bus; F _bRefer to the frequency of stand-by power supply; Δ F _DzRefer to the operating value that frequency difference is out-of-limit, be preferably 0.2～0.5Hz; U _DyThe low-voltage dead lock value of this criterion, because criterion is mainly used in the bus residual voltage amplitude slowly occasion that descends, thus should locking when voltage is low, be preferably 60～80%U _nt _Dz2Represent action delay, generally get 50～100ms.

Frequency difference starts without stream, by reference to the accompanying drawings 8, the criterion that frequency difference starts without stream by to the working power inlet wire without Flow detection, can increase detecting reliability and accelerate detection speed.Particularly, namely do not have effective power input without stream, this moment, load system was dead electricity; And the characteristic of carrying out the traditional frequency detecting of the speed that detects without stream and reliability ratio is good, therefore improve the success rate of switching fast the start-up time that can shorten prepared auto restart by less frequency difference and shorter action delay are set.The criterion that this frequency difference starts without stream has good effect for the load system dead electricity that testing electric power incoming line offside switch or electrical network distant place off-the-line cause.

Particularly, F _Bus＜F _n, (F _b-F _Bus)＞Δ F _Dz, U _Bus＞U _Dy, I _a＜I _Wl, I _b＜I _Wl, I _c＜I _WlAbove-mentioned condition must satisfy simultaneously, by the action delay t that sets _Dz3, this frequency difference starts then to carry out to start without stream moves.U wherein _BusIt is the busbar voltage of frequency measurement; F _BusRefer to the frequency of bus; F _bRefer to the frequency of stand-by power supply; Δ F _DzRefer to the operating value that frequency difference is out-of-limit, be preferably 0.2～0.5Hz; U _DyThe low-voltage dead lock value of this criterion, because criterion is mainly used in the bus residual voltage amplitude slowly occasion that descends, thus should locking when voltage is low, be generally 60～80%U _nI _a, I _b, I _cRefer to the three-phase current of working power inlet wire; I _WlRefer to for the definite value of differentiating without stream, should set according to the certainty of measurement of on-the-spot current circuit, particularly, I _WlValue be the on-the-spot minimum current value that can accurately detect because there is drift in the measuring circuit of measurement mechanism, on-the-spot current transformer has blind area, preferably gets 3～5% load current value; t _Dz3Represent action delay, generally get 20～50ms.

Inverse probability starts, and by reference to the accompanying drawings 9, the criterion that inverse probability starts is by the flow direction of detection power.Particularly, under nominal situation, load obtains energy from electrical network, so power direction points to bus from electrical network, namely the sense of current is for flowing into bus; After the work inlet wire broke down, between bus and power supply, the motor cluster in the load system will cause the fault phase electric current reverse to the fault point feedback current such as the fault point, pointed to electrical network from bus.For the factories and miness that configured house generator, according to the operating standard of electrical network, user's house generator can not send power to electrical network, thus can not produce inverse probability under the nominal situation yet, or the value of inverse probability is very little.The advantage of this inverse probability start-up criterion is fast response time, and needing only one has the fault point, namely can detect reliably about general 20ms; Especially have good response speed and selectivity for the fault that occurs at the bus near-end.And different from the protective relaying device that is installed in mains side, when asymmetry short circuit fault occurs, and the electric current of healthy phases is maximum, and this is that the criterion that inverse probability starts all embodies to some extent because the energy of feedback current provides by the healthy phases electric current.

Particularly, the condition of this inverse probability start-up criterion is: A phase power direction is for flowing out bus, and B phase power direction is for flowing out bus, and C phase power direction is for flowing out bus, I _a＞I _Set, I _b＞I _Set, I _c＞I _SetAbove-mentioned A phase power direction is that outflow bus, B phase power direction are at least one establishment among the outflow bus condition for outflow bus, C phase power direction, and I _a＞I _Set, I _b＞I _Set, I _c＞I _SetAmong at least one set up and the action delay t by setting _Dz4, this inverse probability starts then to carry out to start moves.Wherein, I _a, I _b, I _cRefer to the three-phase current of working power inlet wire; I _SetRefer to the starting current value that inverse probability is differentiated, for the working condition that does not have house generator, preferably be set as the load current value about 10%, in other embodiments, by avoiding normal operation condition inverse probability current settings, be preferably 10～20% load current values; t _Dz4Representing action delay, is cable line such as the bus near-end, preferably choose 20ms or more than, if overhead transmission line because the malfunction that lightning arrester discharge causes will avoid being struck by lightning the time according to the relay protected operation rules, then is set as 80～100ms.

The frequency difference inverse probability starts, by reference to the accompanying drawings 10, the criterion that the frequency difference inverse probability starts is by the flow direction of detection power, emphasis considers that objectively there is certain response time in the generator speed adjusting gear, when load system changes greatly, of short duration inverse probability working condition may appear, guarantee that backup auto-activating device can not malfunction cause unnecessary switching, the variation that just must add the necessary condition-frequency of system splitting is to guarantee the selectivity of backup auto-activating device action.The criterion that this frequency difference inverse probability starts preferably after contacting of bus and electrical network cut off in the protective relaying device action of electrical network offside switch fully, is just carried out the action of electrical source exchange.

Particularly, the condition of this frequency difference inverse probability start-up criterion is: A phase power direction is for flowing out bus, and B phase power direction is for flowing out bus, and C phase power direction is for flowing out bus; I _a＞I _Set, I _b＞I _Set, I _c＞I _SetF _Bus＜F _n, (F _b-F _Bus)＞Δ F _Dz, U _Bsu＞U _DyAbove-mentioned A phase power direction is that outflow bus, B phase power direction are at least one establishment among the outflow bus condition, I for outflow bus, C phase power direction _a＞I _Set, I _b＞I _Set, I _c＞I _SetAmong at least one set up and F _Bus＜F _n, (F _b-F _Bus)＞Δ F _Dz, U _Bus＞U _DyAll set up, and the action delay t by setting _Dz5, this frequency difference inverse probability starts then to carry out to start moves.I _a, I _b, I _cRefer to the three-phase current of working power inlet wire; I _SetRefer to the starting current value that inverse probability is differentiated, for the working condition that does not have house generator, preferably be set as the load current value about 10%, by avoiding normal operation condition inverse probability current settings, be preferably 10～20% load current values in other embodiments; t _Dz5Representing action delay, is cable line such as the bus near-end, generally get more than the 20ms, if overhead transmission line, because the malfunction that lightning arrester discharge causes will avoid being struck by lightning the time according to the relay protected operation rules, then is set as 80～100ms.

In other embodiments, step S100 also comprises the power direction locking, by reference to the accompanying drawings 11, and the criterion of power direction locking refers to bus and each outlet branch by utilizing the sense of current and amplitude to come whether to have the fault point in the cog region in this district.Particularly, more in the outlet branch of manufacturing enterprise's middle voltage bus bar, the probability that breaks down in power supply-distribution system inside is higher, and the block signal of the guard signal of all mesolow branches and equipment as quick electrical source exchange also can not be provided simultaneously; Because the toggle speed of switching is far faster than traditional prepared auto restart, so must consider that the power direction locking cooperates execution with low-voltage protection device.Therefore, backup auto-activating device need to be born in the part cog region, the task of external area error, for the correctness of electrical source exchange provides safeguard.

Particularly, the condition of this power direction locking criterion is: A phase power direction is for flowing into bus, and B phase power direction is for flowing into bus, and C phase power direction is for flowing into bus, I _a＞I _Load, I _b＞I _Load, I _c＞I _Load, U _Ab＜U _Set, U _Bc＜U _Set, U _Ca＜U _SetAbove-mentioned A phase power direction must be simultaneously set up I for inflow bus, C phase power direction for flowing into bus condition for inflow bus, B phase power direction _a＞I _Load, I _b＞I _Load, I _c＞I _LoadAmong the condition at least one set up, and U _Ab＜U _Set, U _Bc＜U _Set, U _Ca＜U _SetAmong the condition at least one set up, and the action delay t by setting _Dz6, block action is then carried out in this power direction locking.I _a, I _b, I _cRefer to the three-phase current of working power inlet wire; I _LoadRefer to the maximum load current under the nominal situation; U _Ac, U _Bc, U _CaRefer to the three-route voltage of dead electricity bus; U _SetRefer to the low-voltage dead lock definite value, be preferably 80% rated voltage; t _Dz6Be the locking time-delay.This locking is divided into two stages, at first be to enter temporary transient blocking without time-delay, after the certain time, enter reliable blocking, need this moment busbar voltage, frequency and power direction to reach the condition of returning and just can reopen prepared auto restart (such as above-mentioned frequency difference inverse probability start-up criterion etc.); Such as the t of blocking time less than preset value _Dz6Locking time-delay, then horse back switchover enabling.This power direction locking criterion causes the operating mode of busbar voltage bust when preferably being applicable to some super-huge motor startings, can avoid the prepared auto restart malfunction.

Locking time-delay t _Dz6Adjust, be divided into two kinds of situations:

The one, bus protection is not installed at the scene, should be under the prerequisite of guaranteeing less than backup protection far away operate time of working power, and it is large that value is tried one's best.Particularly; this backup protection far away refers to operate time; when bus or load branch circuit are short-circuited fault, if the protective relaying device of local installing does not have correct operation (tripping), be installed in the relaying protection operate time of work incoming power side (bus offside or upper level).Be traditionally arranged to be local protection operate time for backup protection far away and add that one differentially (is generally 300～1000ms), to reduce the zone that has a power failure operate time.This is because when busbar fault; if bus protection is not installed at the scene; just must rely on inlet wire backup protection far away to move to excise the fault point; and the busbar fault majority is permanent fault; so device must withdraw from monitored state before backup protection action far away; to guarantee can not switch to start because of low pressure back-up source be put into (after the backup protection action far away, fault current disappears) on the fault bus.For the fault that load branch circuit occurs, then after the corresponding protection action, device is opened all start-up criterion, tripping when to avoid successive failure at once.So for this field working conditions, the backup protection far away of working power inlet wire is longer operate time, this power direction locking criterion is better to the selectivity of busbar fault and load branch circuit fault.

The 2nd, bus protection has been installed at the scene, does not perhaps substantially have the risk of busbar fault, then only considers to get final product greater than the load branch circuit operate time of protection.This moment, only when the branch protection tripping of load system, device withdrawed from the monitored state to load system.

In other embodiments, step S100 comprises that also (this stand-by power supply is generally 95% of stand-by power supply rated voltage to the normal criterion of stand-by power supply when normal, frequency departure is 0.5Hz, i.e. 49.5Hz～50.5Hz), U _Bus＜30%U _n(this condition is " non-" in logic diagram, negate), F _Bus＜40Hz (this condition is " non-" in logic diagram, negate).In one embodiment, the startup of above-mentioned frequency pressure quality, frequency difference start, frequency difference is set up without at least one criterion in stream startup, inverse probability startup, the startup of frequency difference inverse probability, and stand-by power supply is normally set up, and the power direction locking criterion, the U that get negation _Bus＜30%U _n, F _Bus＜40Hz sets up, and then starts and switches tripping working power switch.

S200 gathers the in-put of spare power supply condition.

Particularly, by reference to the accompanying drawings 12, step S210, bus dead electricity.

Step S220 judges whether frequency difference pressure reduction is out-of-limit, is then to enter with no pressure prepared auto restart logic S270, otherwise changes step S230 over to.Particularly, frequency difference Δ f is the 10Hz of rated frequency, and pressure differential deltap V is more than 60% of rated voltage, then to enter next step S230, otherwise change traditional with no pressure prepared auto restart logic S270 over to, wait for that namely the voltage of all load systems reduces to zero, and then drop into stand-by power supply.

Step S230 judges whether house generator withdraws from load system, is then to enter step S240, otherwise enters step S231.Step S231 judges whether to satisfy the simultaneous interconnecting condition, is then to drop into stand-by power supply S260, otherwise returns step S220.Whether particularly, detecting has house generator to withdraw from load system, can by whether detecting frequency difference Δ f greater than 3Hz, be then to force house generator is withdrawed from load system and enters step S240, otherwise enter step S231.Step S231 judges whether to satisfy the simultaneous interconnecting condition, and namely frequency difference Δ f is less than or equal to 3Hz, and the phase angle Δ θ of the phase angle of house generator and stand-by power supply then drops into stand-by power supply S260 if satisfy, otherwise returns step S220 near 0 °.

Step S240 judges whether synchronous motor withdraws from load system, is then to enter step S250, otherwise enters step S241.Step S241 judges whether to satisfy the synchronous motor power supply and drops into criterion, is then to drop into stand-by power supply S260, otherwise returns step S220.Particularly, whether have synchronous motor withdraw from load system, be then to enter step S250, otherwise enter step S241 if detecting.Step S241, judge whether to satisfy the synchronous motor power supply and drop into criterion, namely drop into the frequency difference Δ f of moment less than 5Hz, the port residual voltage is the voltage 60% greater than stand-by power supply at the place, connectivity port between bus and the load circuit, simultaneously frequency difference at Δ f less than 1Hz and angular difference Δ θ less than 65 °, perhaps frequency difference at Δ f less than 5Hz greater than 1Hz and angular difference Δ θ less than 30 °, then drop into stand-by power supply S260 if satisfy, otherwise return step S220.

Step S250 judges whether to satisfy the asynchronous electric power supply and drops into criterion, is then to drop into stand-by power supply S260, otherwise returns step S220.Particularly, load system voltage

And backup power source voltage Homophase, the angular difference Δ θ of in-put of spare power supply moment is preferably 80 ° less than 90 °, and the motor speed of load system is at more than 80% of rated value, and frequency difference then drops into stand-by power supply if satisfy, otherwise returns step S220 in 10Hz.

Whether the house generator in the above-mentioned steps and synchronous motor withdraw from, be whether house generator and synchronous motor are arranged in the load system, can monitor load system by surveillance equipment judge whether house generator and synchronous motor are arranged in the load system.Guarantee fail safe and the success rate of whole in-put of spare power supply process, key is that the operating condition by house generator and synchronous motor in the real time monitoring load system decides the input boundary.It is the loosest that the power supply of asynchronous motor drops into criterion simultaneously, if completely lose the opportunity that the lucid and lively speed of discontented sequitur drops into stand-by power supply.

In other embodiments, at least one step is set up among above-mentioned steps S230, step S240 and the step S250, then enters the step S260 that drops into stand-by power supply.Namely, judge whether house generator withdraws from the step of load system, judge whether synchronous motor withdraws from the step of load system and judge whether to satisfy the step that the asynchronous electric power supply drops into criterion, and wherein at least one set up, and all satisfies the condition of in-put of spare power supply.

S300, by reference to the accompanying drawings 13, the Switching power action is then carried out in this working power switch tripping and meet the in-put of spare power supply condition, drops into stand-by power supply.

In other embodiments, this complete Switching power action also meets unbalance voltage locking criterion.By reference to the accompanying drawings 14, this unbalance voltage locking criterion, when generating region external short circuit fault, after the tripping of working power switch, the fault point disappears, and the bus three-phase voltage should be in a basic balance; Otherwise think still to have short dot in the system, should the locking backup auto-activating device.This unbalance voltage locking criterion is mainly used in the asymmetry short circuit fault that the locking load branch circuit occurs.

U _MaxAnd U _MinRespectively maximum and the minimum value of three line voltages of bus, U _nIt is load voltage value.The characteristics of this unbalance voltage locking criterion are only to disconnect working power and dropping between the stand-by power supply and drop into, and only do temporary transient locking, in case characteristic quantity disappears the control logic of at once open in-put of spare power supply.Particularly, (U _Max-U _Min)＞20%Un, the working power service entrance switch disconnects, and two conditions must set up simultaneously, then is temporary transient locking.This unbalance voltage locking criterion is expressed as negate in the logic diagram that drops into stand-by power supply, be " non-".

In one embodiment, this complete Switching power action also needs again to detect and whether meets the normal criterion of stand-by power supply (this stand-by power supply is generally 95% of stand-by power supply rated voltage when normal, frequency departure is 0.5Hz, i.e. 49.5Hz～50.5Hz).Then complete Switching power action, input stand-by power supply are all satisfied in normal and unbalance voltage locking (this condition be " non-" in logic diagram, negate) when the tripping of working power switch, in-put of spare power supply condition, stand-by power supply.

Based on above-mentioned stand-by power supply changing method, be necessary to provide a kind of stand-by power supply switched system, 15 set forth by reference to the accompanying drawings.

This stand-by power supply switched system comprises processing module 10, the synchronized sampling module 20 that is connected with processing module 10, opens into acquisition module 30 and leaves control module 40.

Synchronized sampling module 20, be used for gathering required electric current, voltage and the frequency values of prepared auto restart control, gather particularly electric current, voltage and the frequency values of the alternating current-direct current of at least one circuit in supply line, stand-by power supply circuit, bus or load circuit and the branch road thereof etc. to factories and miness equicontinuity manufacturing enterprise.The sample frequency of this synchronized sampling module 20 was preferably for 3200 point/seconds, measured simultaneously the frequency of each road voltage signal by " zero passage comparison circuit ".Each synchronized sampling module 20 has all designed electrical isolation and low-pass filter circuit, satisfies the immunity to interference requirement of industry spot.

Open into acquisition module 30, be used for to gather and to open into signal, this is opened and comprises circuit breaker auxiliary contact position signalling, each branch's relay protection signal and control switch signal etc. into signal some are opened into control signal.Particularly, this is opened into acquisition module 30 and preferably gathers opening into signal of 220V/110V, and adopt photoelectric isolation technology, have good anti-interference,

Processing module 10, for the electric current, voltage and the frequency values that gather according to synchronized sampling module 20, and open into opening into signal that acquisition module 30 gathers, control signal is sent in the judgement of criterion and in-put of spare power supply condition by the tripping of above-mentioned working power switch.The establishment of the criterion of this working power switch tripping, comprise aforesaid: press at least one criterion in the criterion that quality starts, frequency difference starts, frequency difference starts without flowing, inverse probability starts, the frequency difference inverse probability starts to set up frequently, stand-by power supply is normal, gets power direction locking criterion, the U of negation _Bus＜30%U _nAnd F _Bus＜40Hz sets up simultaneously.This satisfies the in-put of spare power supply condition, can be by the condition distinguishing of asynchronous motor, and the condition of this asynchronous motor is the loosest.

This processing module 10 also comprises main processing block 11 and from processing module 12, for the treatment of the data more, more complicated than traditional spare power automatic switching system.This main processing block 11 is used for processing according to the value of the electric current, voltage and the frequency that receive; Should be used for the electric current, voltage and the frequency transmission that collect to main processing block 11 from processing module 12, and perhaps receive main processing block 11 result who obtains that processes and generate control signal.This main processing block 11 is RISC MPU at a high speed, is asic chip from processing module 12.

Leave control module 40, the control signal that is used for sending according to processing module 10 is carried out control action.Particularly, control respective circuit breakers deciliter or control switch deciliter.This is left control module 40 and adopts photoelectric coupling and small-sized sealing relay design, has very high environment-adapting ability, can be used in the factory and enterprise of varying environment.

In other embodiments, the stand-by power supply switched system also comprise be connected with processing module 10 leave signaling module 50, be used for the control signal that Graphics Processing module 10 produces, such as plant failure, to switch complete, handoff failure, the position of the switch unusual etc.This is left signaling module 50 and adopts photoelectric coupling and small-sized sealing relay design, and contact rating is 220V/5A.

In other embodiments, the stand-by power supply switched system also comprises the human-computer interaction module 60 that is connected with processing module 10, the operating state that is used for setting the numerical value of relevant criterion or feeds back the stand-by power supply switched system.

In other embodiments, the stand-by power supply switched system also comprises the communication module 70 that is connected with processing module 10, is used for signal transmission, but far distance controlled and understand this stand-by power supply switched system.This communication module 70 is Dual-Ethernet communication module, two RS485 communication module or wifi communication module etc.

In other embodiments, the stand-by power supply switched system also comprises the gps clock module 80 that is connected with processing module 10, is used for correcting the clock information of stand-by power supply switched system, guarantees the timely and accurate of electrical source exchange.

In other embodiments, the stand-by power supply switched system also comprises the printer module 90 that is connected with processing module 10, be used for printing the parameter of stand-by power supply switched system or the operating state of current stand-by power supply switched system etc., such as electric current, voltage and the frequency etc. measured.

In other embodiments, the stand-by power supply switched system also comprises the power module 100 that is connected with processing module 10, is used to the stand-by power supply switched system that DC power supply is provided, and guarantees normal operation.The power supply that provides comprises positive and negative 5V, 12V and 24V etc.

The above embodiment has only expressed several execution mode of the present invention, and it describes comparatively concrete and detailed, but can not therefore be interpreted as the restriction to claim of the present invention.Should be pointed out that for the person of ordinary skill of the art, without departing from the inventive concept of the premise, can also make some distortion and improvement, these all belong to protection scope of the present invention.Therefore, the protection range of patent of the present invention should be as the criterion with claims.

Claims

1. a stand-by power supply changing method is characterized in that, may further comprise the steps:

Start and switch tripping working power switch;

Gather the in-put of spare power supply condition;

The criterion and the in-put of spare power supply condition that meet the tripping of described working power switch are then carried out the Switching power action, drop into stand-by power supply;

Reach described startup switching, the execution of tripping working power switch comprises a kind of of following criterion at least, and described criterion has: press quality startup, frequency difference startup, frequency difference to start and the startup of frequency difference inverse probability without stream startup, inverse probability frequently;

Described frequency presses the condition of quality start-up criterion to be: (U _n-U _Ab)＞Δ U _p, (U _n-U _Bc)＞Δ U _p, (U _n-U _Ca)＞Δ U _p, (F _n-F _Bus)＞Δ F _p, dF/dt＞50Hz/s, above-mentioned condition must satisfy simultaneously, by the action delay t that sets _Dz1, described frequency is pressed quality to start and is then carried out and starts action; U wherein _nAnd F _nThe rated voltage and the rated frequency that refer to respectively load system; U _Ab, U _Bc, U _CaRefer to the three-route voltage of dead electricity bus; F _BusRefer to the frequency of bus; Δ U _pWith Δ F _pRefer to respectively the voltage deviation and the frequency departure that allow come value according to the situation of grid supply quality; DF/dt refers to frequency slip frequency; t _Dz1Represent action delay;

The condition of described frequency difference start-up criterion is: F _Bus＜F _n, (F _b-F _Bus)＞Δ F _Dz, U _Bus＞U _Dy1, above-mentioned condition must satisfy simultaneously, by the action delay t that sets _Dz2, described frequency difference starts then to carry out to start moves; U wherein _BusIt is the busbar voltage of frequency measurement; F _BusRefer to the frequency of bus; F _bRefer to the frequency of stand-by power supply; Δ F _DzRefer to the operating value that frequency difference is out-of-limit; U _Dy1It is the low-voltage dead lock value of described frequency difference start-up criterion; t _Dz2Represent action delay;

Described frequency difference without the condition of stream start-up criterion is: F _Bus＜F _n, (F _b-F _Bus)＞Δ F _Dz, U _Bus＞U _Dy2, I _a＜I _Wl, I _b＜I _Wl, I _c＜I _WlAbove-mentioned condition must satisfy simultaneously, by the action delay t that sets _Dz3, described frequency difference starts then to carry out to start without stream moves; U wherein _BusIt is the busbar voltage of frequency measurement; F _BusRefer to the frequency of bus; F _bRefer to the frequency of stand-by power supply; Δ F _DzRefer to the operating value that frequency difference is out-of-limit; U _Dy2That described frequency difference is without the low-voltage dead lock value of stream start-up criterion; I _a, I _b, I _cRefer to the three-phase current of working power inlet wire; I _WlRefer to for the definite value of differentiating without stream; t _Dz3Represent action delay;

The condition of described frequency difference inverse probability start-up criterion is: A phase power direction is for flowing out bus, and B phase power direction is for flowing out bus, and C phase power direction is for flowing out bus; I _a＞I _Set, I _b＞I _Set, I _c＞I _SetF _Bus＜F _n, (F _b-F _Bus)＞Δ F _Dz, U _Bus＞U _Dy3Above-mentioned A phase power direction is that outflow bus, B phase power direction are at least one establishment among the outflow bus condition, I for outflow bus, C phase power direction _a＞I _Set, I _b＞I _Set, I _c＞I _SetAmong at least one set up and F _Bus＜F _n, (F _b-F _Bus)＞Δ F _Dz, U _Bus＞U _Dy3All set up, and the action delay t by setting _Dz5, described frequency difference inverse probability starts then to carry out to start moves; I _a, I _b, I _cRefer to the three-phase current of working power inlet wire; I _SetRefer to the starting current value that inverse probability is differentiated; Udy ₃It is the low-voltage dead lock value of described frequency difference inverse probability start-up criterion; t _Dz5Represent action delay.

2. stand-by power supply changing method according to claim 1 is characterized in that, described startup is switched, and the step of tripping working power switch also comprises the criterion of power direction locking.

3. stand-by power supply changing method according to claim 1 is characterized in that, described startup is switched, and the step of tripping working power switch also comprises U _Bus＜30%U _nCriterion and/or F _BusThe criterion of＜40Hz;

Described U _BusIt is the busbar voltage of frequency measurement; Described U _nIt is the rated voltage of load system; Described F _BusRefer to the frequency of bus.

4. the described stand-by power supply changing method of any one is characterized in that according to claim 1～3, and described startup is switched, and the step of tripping working power switch also comprises the normal criterion of stand-by power supply.

5. stand-by power supply changing method according to claim 1 is characterized in that, described collection in-put of spare power supply condition comprises:

Step S210, the bus dead electricity;

6. stand-by power supply changing method according to claim 1 is characterized in that, describedly meets the criterion of described working power switch tripping and the condition of in-put of spare power supply condition also comprises: the normal criterion of stand-by power supply.

7. stand-by power supply changing method according to claim 1 is characterized in that, describedly meets the criterion of described working power switch tripping and the condition of in-put of spare power supply condition also comprises: the criterion of unbalance voltage locking.

8. a stand-by power supply switched system is characterized in that, comprising: processing module, and the synchronized sampling module that is connected with processing module, open into acquisition module and leave control module;

The synchronized sampling module is used for gathering electric current, voltage and frequency values;

Open into acquisition module, be used for to gather and to open into signal, the described signal of opening comprises at least a in circuit breaker auxiliary contact position signalling, relay protection signal and the control switch signal;

Processing module, for the electric current, voltage and the frequency values that gather according to described synchronized sampling module, and open into opening into signal that acquisition module gathers, judge by criterion and in-put of spare power supply condition to the tripping of working power switch, send control signal; The criterion of described working power switch tripping comprise frequently press that quality starts, frequency difference starts, frequency difference without stream start, inverse probability starts, at least a in starting of frequency difference inverse probability;

Leave control module, the control signal that is used for sending according to processing module is carried out control action.

The condition of described frequency difference inverse probability start-up criterion is: A phase power direction is for flowing out bus, and B phase power direction is for flowing out bus, and C phase power direction is for flowing out bus; I _a＞I _Set, I _b＞I _Set, I _c＞I _SetF _Bus＜F _n, (F _b-F _Bus)＞Δ F _Dz, U _Bus＞U _Dy3Above-mentioned A phase power direction is that outflow bus, B phase power direction are at least one establishment among the outflow bus condition, I for outflow bus, C phase power direction _a＞I _Set, I _b＞I _Set, I _c＞I _SetAmong at least one set up and F _Bus＜F _n, (F _b-F _Bus)＞Δ F _Dz, U _Bus＞U _Dy3All set up, and the action delay t by setting _Dz5, described frequency difference inverse probability starts then to carry out to start moves; I _a, I _b, I _cRefer to the three-phase current of working power inlet wire; I _SetRefer to the starting current value that inverse probability is differentiated; U _Dy3It is the low-voltage dead lock value of described frequency difference inverse probability start-up criterion; t _Dz5Represent action delay.

9. stand-by power supply switched system according to claim 8 is characterized in that, also comprises: what be connected with processing module leaves signaling module, is used for the control signal that the Graphics Processing module produces; The gps clock module that is connected with processing module is for the clock information of correcting the stand-by power supply switched system.

10. stand-by power supply switched system according to claim 8 is characterized in that, also comprises: the human-computer interaction module that is connected with processing module, the operating state that is used for setting the numerical value of relevant criterion and/or feeds back the stand-by power supply switched system; The communication module that is connected with processing module is used for signal transmission, far distance controlled and understands described stand-by power supply switched system; The printer module that is connected with processing module is for the parameter of printing the stand-by power supply switched system; The power module that is connected with processing module is used to the stand-by power supply switched system that DC power supply is provided.