CN104426115A - Method for checking communication link between two switches of switch mechanism and corresponding checking device - Google Patents

Abstract

The invention relates to a method for checking a communication link (K1) between two switches (CB1 and CB3). The switches are directly connected in series; each of the switches (CB1 and CB3) is used for checking whether electric energy flowing through a contact element meets a rated condition; a tripping unit ETU of the upstream switch (CB1) is provided with energy (EQP1); the energy and a switch device (SO) of the tripping unit ETU of the downstream switch (CB3) form a circuit through the communication link (K1), so that a signal (S) with a voltage change form and/or a current change form is generated; the switch device (SO) of the downstream switch (CB3) is used for switching on or switching off the circuit. In order to realize a technically simple method and a technically simple device, the method provided by the invention has the advantages that on the premise that a condition cannot be met, within a rated time interval, (a) the upstream switch awaits for the signal (S), (b) the downstream switch generates the signal (S), and (c) if the upstream switch (CB1) detects the signal (S) within the time interval, the communication link (K1) is normal.

Description

Check the method for the communication link of two switch rooms of switching mechanism and corresponding testing fixture

Technical field

The present invention relates to and check the method for the communication link of two switch rooms of switching mechanism and a kind of corresponding testing fixture according to claim 1 and the as described in the preamble a kind of of claim 6.

Background technology

As everyone knows, by the switch in switching mechanism, particularly low-voltage circuit breaker, electric current is dispensed to equipment bypass or power consumption equipment in distribution system.These switches design for a rated current respectively and the electric current that will flow through when breaking down (as short circuit) disconnects.Wherein, only disconnect by fault effects or closest to that equipment bypass of fault.This operation is called selectivity open circuit.

A current transformer and a trip unit is equipped with in each switch.Current transformer detects the electric current flowing through this switch, and trip unit checks whether the condition (as current condition) conformed with the regulations.

When implementing selectivity open circuit, these switches communicate mutually.Such as when there is the situation meeting this current condition because of short circuit, with regard to supplier of electricity to regard to be in downstream a switch by a signal (block signal or inhibit signal), this situation is notified its upstream switch.In the case, same find that this upstream switch self of short circuit is not temporarily first threaded off, but wait for certain time of delay and observe downstream switches whether thread off.If this downstream switches is not threaded off after expiring time of delay, then electric current disconnects self by this upstream switch.The shortcoming of this mode is, is disconnected and may cause heavy losses by communication link.

Summary of the invention

The object of this invention is to provide a kind of technically simple method checking the communication link of two switch rooms of distribution switching mechanism, and the testing fixture of relatively minor change made by a kind of needs.The present invention implements to check in switching manipulation process.

In method and testing fixture, the present invention is respectively claim 1 and feature according to claim 6 in order to the solution reaching above-mentioned purpose.Expedients scheme of the present invention consults dependent claims.

According to the solution of the present invention in method, in a regulation time slot, a) described signal is waited for by described upstream switch when ineligible, b) described signal is produced by described downstream switches, if and c) described upstream switch detects described signal in described time slot, then described communication link is normal.

According to one technically simple embodiment, each switch all has a processor, and wherein, the processor of described downstream switches is by described closing of circuit or disconnection, and the processor of described upstream switch detects described change in voltage and/or curent change.

If each switch not only has an energy but also have a switching device, for forming described circuit, described switching device and described communication link link together according to the described sense of current by described processor, then only need to make minimum change in the electronic device.

Described signal has the signal length of a regulation, and therefore, described method can reduce complexity.

According to one technically simple embodiment, each switch all has a trip unit, and whether the electric energy that described trip unit autoscopy flows through described switch meets described condition, and situation about meeting or do not meet described condition is notified described processor.

According to the solution of the present invention in device, when ineligible, in a regulation time slot, a) described upstream switch waits for described signal, b) described downstream switches produces described signal, if and c) described upstream switch detects described signal in described time slot, then described communication link is normal.

Accompanying drawing explanation

Fig. 1 is a switching mechanism be not short-circuited;

Fig. 2 is for being short-circuited after switching mechanism shown in Fig. 1 wherein a limit switch;

Fig. 3 is the schematic diagram of the trip unit of switch shown in a Fig. 1;

Fig. 4 is trip unit shown in two connected Fig. 3;

Fig. 5 is the modified model trip unit with testing fixture; And

Fig. 6 is trip unit shown in two connected Fig. 5.

Embodiment

By embodiment, the present invention is described in detail below.

Fig. 1 is the schematic diagram of distribution switching mechanism 1, comprise five be embodied as low-voltage circuit breaker and connect two power supply units TM(TM1, TM2) switch CB(CB1, CB2, CB3, CB4, CB5), wherein, switch CB3 is arranged in a bridge branch.The upper type of attachment of switch CB4, CB5 is power consumption equipment L1, L2 of motor.

Switch CB forms multiple Switch Controller, and it is made up of two switches that directly electricity is connected respectively, that is what flow through these two switch CB is same electric current (at least same shunting) and there is not any other switch CB between these two switches.In Fig. 1, CB1 and CB3, CB3 and CB4, CB1 and CB4, CB2 and CB3, CB3 and CB5, CB2 and CB5 form a Switch Controller respectively.Switch CB1, CB3 and the CB4 of Switch Controller and Switch Controller CB2, CB3 and CB5 are electrically connected to each other and communicate to connect (hereafter will give elaboration).

For simplicity, all switch CB in the present embodiment all adopt identical embodiment.

Each switch CB all have can machinery be separated contact element, these contact elements form a switch contact respectively in couples, and electric current can flow through respective switch CB1, CB2, CB3, CB4, CB5 via this switch contact.

Each switch also has electronics trip unit ETU(ETU1, ETU2, ETU3, RTU4, an ETU5), whether whether the electric energy (electric current) that switch CB is flow through in described trip unit inspection meets the current condition (being generally speaking a condition) of a regulation, refer to here more than a threshold value.

Depict in switching mechanism 1 and flow through respective switch CB(CB1, CB2, CB3, CB4, CB5) standard (i.e. benchmark) sense of current R(R1, R2, R3, R4, R5).

The trip unit ETU of these switches CB is by communication link K(K1, K2) be connected, communication link is here embodied as the respective terminal A of each trip unit ETU, B(A1, B1, A2, B2, A3, B3, A4, B4, A5, B5) two wire link that links together.

Switch CB1, CB3 and CB4 are communicated by communication link K1, and switch CB2, CB3 and CB5 are communicated by communication link K2.

Fig. 2 is short-circuited before the switch CB5 being set to limit switch, and this short circuit lightning symbol F represents.Compared to Figure 1, sense of current R is not short-circuited associated change.Sense of current R also may reverse in principle when being short-circuited, specifically depending on location of short circuit.

All switch CB all implement selectivity open circuit (ZSI, inter-stage selectivity is chain), that is when meeting current condition, the trip unit ETU of the trip unit ETU being in the switch CB in downstream with regard to sense of current R upstream switch CB sends a signal SV.This signal SV notifies that this upstream switch CB: downstream switches CB will disconnect, and for this reason, the trip unit of upstream switch CB is not at least threaded off immediately, but just threads off when downstream switches CB is not yet disconnected after terminating the time of delay specified.

According to the electric current flowing through two switches, the trip unit of upstream switch CB finds that this current condition has met equally, this trip unit originally can be implemented when not receiving signal SV to thread off, after receiving signal SV, this trip unit is not temporarily first threaded off, but waits for whether downstream switches CB announces to thread off by signal SV.

For simplicity, following embodiment is only with an independent Switch Controller, and the Switch Controller namely comprising switch CB1 and CB3 is that example is described.These embodiments are all applicable to every other Switch Controller.

Switch CB3 in Fig. 2 is arranged in switch CB1 downstream (namely switch CB1 is arranged in switch CB3 upstream).Be short-circuited F time, the threshold value of the current condition of switch CB1 and switch CB3 is exceeded.Its trip unit of switch CB3(ETU3 in downstream is in regard to sense of current R) corresponding its trip unit of upstream switch CB1(ETU1) send signal SV, by illustrating this point from the oblique arrow ZSI of switch CB3 directing switch CB1 in Fig. 1.Its trip unit of switch CB1(ETU1) know at this point this be positioned at downstream and closer to its trip unit of switch CB3(of short circuit F) will disconnect (dropout).In the case, switch CB1 self does not first disconnect.

Fig. 3 is the schematic diagram of the trip unit ETU of an exemplary switch CB of all switch CB of representative, for setting forth operation principle.But this embodiment is also not suitable for checking communication link K.

After combining signal SV, described ETU comprises the signal element cell S EE that a form is the first expansion module, its independent grafting and have an an energy EQ and switch element SS.Energy EQ has two terminals I-, I+, and switch element SS has terminal O-, O+, and as shown in Figure 3, these terminals are connected with terminal OE-, OE+, IE-, IE+ of a converting unit UE.Converting unit UE is embodied as the second expansion module at this and is correspondingly plugged to the first expansion module.When meeting current condition, consult Fig. 1 and 2 according to sense of current R() send signal SV, by terminal B Received signal strength SV by terminal A.

This situation reverses when sense of current R reverses: send signal by terminal B, Received signal strength on terminal A.Utilize converting unit UE(Fig. 1 and 2: UE1, UE2, UE3, UE4, UE5) implement reversion.One is integrated with for detecting unit EE(Fig. 1 and 2: EE1 of sense of current R, EE2, EE3, EE4, EE5 in converting unit UE), this detecting unit is applied in (air core coil) current transducer signal SW and the digital data processing unit utilizing a form to be processor CPU measure the sense of current (R1, R2, R3, R4, R5).(processor CPU here specially refers to microprocessor).

Converting unit UE has each two bus Bus_O and Bus_I, and wherein, O represents Output, and I represents Input.Bus Bus_O, Bus_I are by direction switch SAO, SAI, SBO, SBI and terminal A(AIO+, AIO-), B(BIO+, BIO-) be alternately connected.In Fig. 3, direction switch SAO and SBI is in closure state, direction switch SAI and SBO1 off-state.Processor CPU utilizes switching signal CAO according to the sense of current R flowing through switch CB, CAI, CBO, CBI implement closed to all direction switch SAO, SAI, SBO, SBI and disconnect.(when the sense of current flowing through switch occurs to reverse-such as, when the sense of current in Fig. 2 occurs to reverse for Fig. 1-, direction switch SAI and SBO closes and is disconnected by direction switch SAO and SBI by processor CPU.）

The switch element SS of signal element cell S EE is connected with bus Bus_O by terminal OE-, OE+, is connected with terminal A by bus Bus_O.This switch element SS has a switching transistor T, and the volume resistivity of this switching transistor is changed (control) by a light signal So_x by trip unit ETU.That is switching transistor T is subject to make-break operation in the mode being similar to switch.

The energy EQ of signal element cell S EE is connected with bus Bus_I by terminal IE-, IE+, is connected with terminal B by bus Bus_I.Energy EQ is made up of the direct voltage source U of a 15V, resistor W1, W2 and a photodiode D, and this photodiode transmits the light signal Si_x be directly proportional to electric current to trip unit ETU.

Owing to constructing respective extension module, described converting unit UE has an own processor CPU.

Fig. 4 is trip unit ETU1, the ETU3 of switch CB1, CB3 shown in two connected Fig. 1.For trip unit ETU4, in figure, illustrate only the terminal (consulting Fig. 1) that it connects two trip units ETU1, ETU3 in described communication link K1.

The switch element SS3 of the signal element cell S EE3 of downstream switches CB3 is connected with the terminal B1 of upstream switch CB1 with communication connection K1 by the terminal A3 of this downstream switches, and terminal B1 is connected with the energy EQ1 of signal element cell S EE1 equally.Switch element SS3, communication connection K1 and energy EQ1 jointly form one and can be disconnected by switch element SS3 and closed circuit.

If trip unit ETU3 finds to have met this current condition and transmits one by light signal So_x closed for switch element SS3 accordingly, thus sends a signal SV to trip unit ETU1 in the circuit, then this circuit respective closed.Produce described signal SV with the form of change in voltage and/or curent change and detected by trip unit ETU1.Closing period is 100ms, and this point corresponds to the signal SV that signal length is 100ms.Detected by the photodiode D of the light signal Si_x be directly proportional to electric current to the corresponding transmission of trip unit ETU1.After receiving light signal Si_x, switch CB1 threads off after terminating time of delay early than a regulation by trip unit ETU1, that is, only just thread off when the trip unit ETU3 of downstream switches CB not yet threads off.

As the replacement scheme implementing closed procedure, also this circuit can be disconnected and make occurred change in voltage and/or curent change form signal SV.

Fig. 5 is the device (testing fixture) for checking the communication link K between two adjacent switch CB, and this device is incorporated into for this reason and in the converting unit UE improved of these two switch CB.The main element of this testing fixture comprises: one set up comprise energy EQP, signaling switch SEO, a switch S EI and switching device SO that is embodied as the signal element SI of photodiode.These elements and direction switch SAO, SAI, SBO, SBI carry out acting in conjunction, and above-mentioned direction switch is corresponding to the direction switch (SAO, SAI, SBO, SBI) in Fig. 3 and 4.Both direction switch S AO and SBI is in closure state, or both direction switch S AI and SBO is in closure state, specifically depending on sense of current R.In Fig. 5, direction switch SAO and SBI is in closure state, that is, by the signal S of terminal A output one with the signal that conducts a survey.

Energy EQP is made up of the direct voltage source UP of a 15V, resistor WP1, WP2 and a photodiode SI.

On terminal B, whether there is light signal SO_x and/or signal SV in order to checking, namely checking whether the current condition at least met for a switch CB, when direction switch SAO is closed by switch S BI and SEI alternately closed and disconnected.If detect on photodiode SI these two signals SO_x, SV one of them or signal SA detected, then switching device SO is activated and pass through terminal A output signal SV.

Direction switch SBI be in off-state and switch S EI is in closure state time: if trip unit ETU find current condition met, then it utilizes light signal So_x to be communicated with by switching transistor T.Change in voltage and/or curent change is caused in the closed circuit that this measure is formed at energy EQP and switching transistor T.Subsequently, signal element SI transmits a signal SA to processor CPU, the switching device SO being embodied as switching transistor is equally closed the duration of 100ms by this processor accordingly, as previously mentioned, to produce signal length in the circuit be in this way the form of 100ms is the signal SV of relevant voltage change and/or curent change.

In view of this, also can think export or have sent this change in voltage and/or curent change, because particularly when electric current changes, above-mentioned change in voltage and/or curent change can detect on each position of circuit.

Direction switch SBI be in closure state and switch S EI is in off-state time: downstream switches CB is by this closing of circuit, thus produce by terminal B change in voltage and/or the curent change that flows through this downstream switches, in the case, processor CPU in Fig. 5 recognizes signal SV by signal element SI, because current condition is met, therefore, this processor exports a switching signal CEO to signaling switch SEO.

Under normal operating state, direction switch SAO, SBI close subsequently and switch S EI disconnects, because all do not meet for the current condition of this switch CB and this downstream switches.

Implement under normal operating condition to check operation, that is, by switching device SO(in short-term) activate 1ms and do not meet current condition.

In the time slot of a second, (namely per second) carries out Periodic activation to described switching device SO.

When switch S EI is in off-state, switching device SO is closed the duration of 1ms by processor CPU.The upstream switch CB connected by terminal A recognizes the change in voltage and/or curent change that signal length is 1ms, and this signal length is same corresponding with closing period.

Fig. 6 is connected trip unit ETU1, the ETU3 of two of switch CB1, the CB3 with testing fixture.For simplicity, the terminal of two trip units ETU1, ETU3 that trip unit ETU4 connects in described communication link K1 does not give display.

Do not meet current condition, that is, be in normal operating state and the switch S EI of converting unit UE1, UE3 is in off-state.

For implementing to check, by the processor CPU of converting unit UE3, the switch element SO of converting unit UE3 is closed the duration of 1ms.The upstream switch CB1(terminal B1 connected by terminal A3) be that the change in voltage of 1ms and/or curent change are identified as signal S by signal length, namely check signal, in other words, this switch CB1 receives this inspection signal.

Specify that in time slot, after referring to be later than one second most here, (per second) waits for described signal S, wherein, if do not meet current condition, then terminates next time slot after-applied at a time slot by the processor CPU of converting unit UE1 one.

If signal S disappears in the time slot of a second, then communication link K1 is abnormal.Also the faults such as broken string can be included in examination scope by waiting signal S within a timeslot.

Unique difference of signal SV and S is signal length (100ms and 1ms), and for avoiding conflict, what check signal S employing is change in voltage very short on the time and/or curent change.

Implement in some way to check, make upstream switch CB1 identification communication link K whether normal, and the corresponding triggering of downstream switches CB3 checks.

In other words: downstream switches CB triggers inspection, upstream switch CB identifies and corresponds to signal S(and check signal) and there is change in voltage and/or the curent change of corresponding signal length, wherein, this upstream switch is recognized from not meeting this information of current condition: just with downstream switches CB for starting point to communication link K implement check.Waiting signal S can play supplementary function to described inspection within a timeslot.

If communication connection K is abnormal, then such as this situation notified outside with the form of light signal, like this, operating personnel are easy to just can find fault.As an alternative, also can such as by a signalling contact by this information transmission to superordinate elements (control unit or control system).

Claims (10)

1. check a method for the communication link (K1) between two switches (CB1, CB3), described switch has can the contact element that is separated of machinery and directly connecting for realizing distribution,

Wherein, each switch (CB1, CB3) all there is a trip unit (ETU1, ETU3), whether the electric energy that described trip unit inspection flows through described contact element meets a rated condition, wherein, with regard to the sense of current (R), the trip unit (ETU1) of the switch (CB1) of upstream has an energy (EQP1), the described energy forms a circuit by described communication link (K1) and a switching device (SO) of the trip unit (ETU) of described downstream switches (CB3), for producing the signal (S) that a form is change in voltage and/or curent change, the switching device of described downstream switches (CB3) (SO) is utilized to close or disconnect described circuit, it is characterized in that,

When ineligible in a regulation time slot

A) described signal (S) is waited for by described upstream switch,

B) described signal (S) is produced by described downstream switches, and

If c) described upstream switch (CB1) detects described signal (S) in described time slot, then described communication link (K1) is normal.

2. method according to claim 1, is characterized in that,

Each switch (CB) all has a processor (CPU), and wherein, the processor (CPU) of described downstream switches is by described closing of circuit or disconnection, and the processor of described upstream switch detects described change in voltage and/or curent change.

3. method according to claim 1 and 2, is characterized in that,

Each switch (CB1, CB3) both there is a energy (EQP1, EQP3) have again a switching device (SO), for forming described circuit, described switching device and described communication link (K1) link together according to the described sense of current (R) by described processor (CPU).

4. the method any one of claim 1-3 described in claim, is characterized in that,

Described signal (S) has the signal length of a regulation.

5. the method any one of claim 1-4 described in claim, is characterized in that,

Each switch (CB1, CB3) all have a trip unit (ETU1, ETU3), described switch (CB1 is flow through in described trip unit inspection, whether electric energy CB3) meets described condition, and situation about meeting or do not meet described condition is notified described processor (CPU).

6. one kind for checking two switch (CB1, the device of the communication link (K) CB3), described switch have can machinery be separated contact element and directly connect for realizing distribution, wherein, each switch (CB1, CB3) all has a trip unit (ETU1, ETU3), whether the electric energy that described trip unit inspection flows through described contact element meets a rated condition

Described device comprises a circuit, described circuit is made up of a switching device (SO) of the trip unit (ETU3) of the energy (EQP1) of the trip unit (ETU1) of the switch (CB1) of upstream with regard to the sense of current (R), described communication link (K1) and described downstream switches (CB3), for producing the signal that a form is change in voltage and/or curent change, the switching device (SO) of the trip unit (ETU3) of described downstream switches (CB3) is closed or disconnect described circuit, it is characterized in that

When ineligible in a regulation time slot

A) described upstream switch waits for described signal (S),

B) described downstream switches produces described signal (S), and

If c) described upstream switch (CB1) detects described signal (S) in described time slot, then described communication link (K1) is normal.

7. device according to claim 6, is characterized in that,

Each switch (CB) all has a processor (CPU), and wherein, the processor (CPU) of described downstream switches is by described closing of circuit or disconnection, and the processor of described upstream switch detects described change in voltage and/or curent change.

8. the device according to claim 6 or 7, is characterized in that,

Each switch (CB1, CB3) both there is a energy (EQP1, EQP3) have again a switching device (SO), for forming described circuit, described switching device and described communication link (K1) link together according to the described sense of current (R) by described processor (CPU).

9. the device any one of claim 6-8 described in claim, is characterized in that,

Described signal (S) has the signal length of a regulation.

10. the method any one of claim 6-9 described in claim, is characterized in that,

Each switch (CB1, CB3) all have a trip unit (ETU1, ETU3), described switch (CB1 is flow through in described trip unit inspection, whether electric energy CB3) meets described condition, and situation about meeting or do not meet described condition is notified described processor (CPU).