There is the protector of current mutual inductor of remote short messages warning function
Technical field
The present invention relates to a kind of current transformer protective device, in particular for sending the protective device of SMS alarm during unattended Current Transformer Secondary side overvoltage overcurrent abnormality.
Background technology
Current transformer is that electric power system must indispensable components and parts, is that transforming plant protecting device plays current transformation and electrical isolation effect, is applied to the differential winding of various CT secondary side, overcurrent winding, measures winding, bus protection winding and measure first-class.Along with the continuous increase of electric power system capacity, the shortcoming that current transformer exposes is more and more outstanding.Operating current transformer, the load that its secondary side connects is instrument or relay current coil etc., impedance is very little, substantially short-circuit condition is run on, the magnetic flux that secondary current produces and the mutual degaussing of magnetic flux that primary current produces, make the magnetic flux density in iron core can maintain lower level, the secondary voltage of current transformer is also very low.The current transformer secondary side that is in operation must not be opened a way, the secondary side of some current transformer is a certain contact bad, ageing of insulation, phase current is uneven, secondary side is caused to open a way, if can not be changed by Timeliness coverage, first side winding suffers lightning current, resonance current, the abnormal currents such as capacitance charging current impact, the secondary side of current transformer will produce the high pressure of thousands of volt, because iron loss is excessive, temperature is too high and burn, more serious secondary winding voltage is raised and by insulation breakdown and bring disaster to the apparatus insulated damage of secondary load, this works the mischief not only to secondary side system insulation, current transformer also can be made too drastic and burn, even jeopardize the life security of staff.
Chinese patent literature CN102324729A discloses a kind of secondary over-voltage protector for current transformer: the two ends being parallel to current transformer between described sampling input, is connected with bidirectional triode thyristor between sampling input; Be parallel with piezo-resistance between sampling input, the other end of piezo-resistance is connected with trigger, and the base stage of termination first triode drawn by trigger; The grounded collector of the first triode, its emitter is connected to malfunction indicator lamp, the base stage of the second triode, the second optocoupler; The collector connecting relay of the second triode.This device uses bidirectional triode thyristor to carry out short-circuit protection to current transformer when current transformer produces overvoltage, and controllable silicon switching action is fast.But this device voltage detecting circuit adopts bridge rectifier, ripple coefficient is comparatively large, and sampled voltage stability is bad, very easily produces misoperation; Because optocoupler components overcurrent is little, easily because of high pressure or surge punch through damage, when after triode ON due to inverse electromotive force can not be fallen by decrease uptake, be easy to make triode T7 heating burnout.
Summary of the invention
The technical problem to be solved in the present invention is to provide a kind of protector of current mutual inductor with remote short messages warning function; can the short circuit current protection mutual inductance and send audio alert when overvoltage, overcurrent abnormality appear in current transformer, simultaneously by SMS notification staff.
For solving the problems of the technologies described above, the technical solution used in the present invention is:
There is the protector of current mutual inductor of remote short messages warning function, comprise current collection circuit, protect executive circuit, compare circuits for triggering, guard signal control circuit, photoelectric isolating circuit, power circuit, single chip circuit, SMS alarm circuit and voice alarm module, current collection circuit comprises ammeter A1, ammeter A2 and resistance R11, ammeter A1 connects the current transformer LA of A phase, and ammeter A2 connects B phase current mutual inductor LB; Ammeter A1 and ammeter A2 is connected in parallel resistance R11, resistance R11 connects and compares circuits for triggering, relatively circuits for triggering connect guard signal control circuit, and guard signal control circuit connects protection executive circuit, and protection executive circuit connects current transformer LA summation current transformer LB; Relatively circuits for triggering connect single chip circuit by photoelectric isolating circuit, and single chip circuit connects SMS alarm circuit and voice alarm module respectively; Power circuit connects respectively and compares circuits for triggering, guard signal control circuit, single chip circuit, SMS alarm circuit and voice alarm module.
Further improvement of the present invention is: protection executive circuit comprises ammeter A, resistance R11, bidirectional triode thyristor Q5, electric capacity C6, resistance R18, socket P2, ammeter A one end connects current transformer LA one end, the other end connects the current transformer LA other end and bidirectional triode thyristor Q5 respectively, and bidirectional triode thyristor Q5 is connected by resistance R11 and compares circuits for triggering; Bidirectional triode thyristor Q5 is connected in parallel electric capacity C6 and resistance R18 respectively, and bidirectional triode thyristor Q5 connects guard signal control circuit by diode D3 connection socket P2, socket P2.
Further improvement of the present invention is: compare that circuits for triggering comprise amplifier IC3, emitter follower Q2, resistance R5, amplifier IC3 form by by chip OPA2277 series resistor, and 3 pins of chip OPA2277 connect the ammeter A of protection executive circuits; Described emitter follower Q2 is connected in series by triode and resistance to form; Amplifier IC3 connects emitter follower Q2 by resistance R5; Emitter follower Q2 connects photoelectric isolating circuit, and emitter follower Q2 connects guard signal control circuit, and 5 pins of fortune chip OPA2277 connect the ammeter of stream collection and protection executive circuit, and 8 pins of chip OPA2277 connect power circuit.
Further improvement of the present invention is: guard signal control circuit comprises electronic switch IC1, triode Q14, triode Q12, socket P1, electric capacity C1, resistance R4, rheostat K1 and resistance R8, electronic switch IC1 is TWH8778 chip, 1 pin of electronic switch IC1 connects the emitter follower Q2 comparing circuits for triggering, 2 pins, 3 pin serial connection of electronic switch IC1 pass through electric capacity C1 connecting triode Q14, triode Q14 is by resistance R8 connection socket P1, electric capacity C1 is by resistance R4 connecting triode Q12, triode Q12 connection socket P1; Socket P1 connects the socket P2 of protection executive circuit.
Further improvement of the present invention is: photoelectric isolating circuit comprises triode Q8, photoelectrical coupler U1, resistance R30 and resistance R31, the B collection of triode Q8 connects 5 pins comparing the amplifier IC3 of circuits for triggering, the C collection of triode Q8 connects 2 pins of photoelectrical coupler U1,1 pin of photoelectrical coupler U1 connects power circuit by resistance R30,4 pins of photoelectrical coupler U1 connect single chip circuit, 4 pins of photoelectrical coupler U1 connect power circuit by resistance R31, the 3 pin ground connection of photoelectrical coupler U1.
Further improvement of the present invention is: single chip circuit comprises single-chip microcomputer IC5, chip IC 6, crystals vibrate device Y1, electric capacity C13, electric capacity C14, resistance R36 and computer connecting circuit, single-chip microcomputer IC5 is SCT89C52 single-chip microcomputer, chip IC 6 is X5045 chip, chip IC 6 connects power circuit, chip IC 6 connects single-chip microcomputer IC5, one end of crystals vibrate device Y1 connects the XTAL1 pin of single-chip microcomputer IC5 and by electric capacity C14 ground connection, the other end of crystals vibrate device Y1 connects the XTAL2 pin of single-chip microcomputer IC5 also by electric capacity C13 ground connection; Described computer connecting circuit comprises computer interface J1 and chip MA232, and 10 pins, 11 pins of single-chip microcomputer IC3 connect chip MA232, and chip MA232 connects computer interface J1; The INT pin of single-chip microcomputer IC3 connects 4 pins of the photoelectrical coupler U1 of photoelectric isolating circuit, and 4 pins of single-chip microcomputer IC3 connect voice alarm module, and 10 pins, 11 pins of single-chip microcomputer IC3 connect SMS alarm circuit.
Further improvement of the present invention is: described voice alarm module comprises speech chip IC10, triode Q9, triode Q11, loud speaker LS1, resistance R38, resistance R40 and electric capacity C24, speech chip IC10 is SC020B chip, speech chip IC10 connects the single-chip microcomputer of single chip circuit by triode Q9, speech chip IC10 connects triode Q11 by resistance R38, triode connects loud speaker LS1, loud speaker LS1 connecting triode Q9; Speech chip IC10 connects power circuit by electric capacity C24, and triode Q11 connects power circuit by resistance R40.
Further improvement of the present invention is: SMS alarm circuit comprises gsm module, inductance L 1, SIM card, triode Q6, light-emitting diode D2, light-emitting diode D4 and light-emitting diode D5, gsm module is TC35i module, gsm module connects power circuit by inductance L 1, gsm module connects SIM card, gsm module connecting triode Q6, triode Q6 connects power circuit by light-emitting diode D2, and triode Q6 is connected the single-chip microcomputer IC5 of single chip circuit with light-emitting diode D5 by the light-emitting diode D4 that is connected in parallel.
Further improvement of the present invention is: power circuit comprises mains switch S3, insurance F1, piezo-resistance R39, transformer T1, bridge rectifier D 7, filter circuit IC7, filter circuit IC8 and pressurizer IC11, mains switch S3 one end connects 220V power supply, the other end is respectively connected filter circuit IC7 and filter circuit IC8 with piezo-resistance R39 connection transformer T1, transformer T1 by bridge rectifier D 7 by insurance F1, filter circuit IC7 is that LM7806 chip is formed by inductance serial connection, and filter circuit IC7 connects and compares circuits for triggering, guard signal control circuit; Filter circuit IC8 is that LM7805 chip is formed by inductance serial connection, and filter circuit IC8 connects single chip circuit, voice alarm module, and connects SMS alarm circuit by pressurizer IC11.
Owing to adopting technique scheme, the beneficial effect that the present invention produces is:
The protector of current mutual inductor with remote short messages warning function of the present invention can carry out short-circuit protection to current transformer under current transformer produces overcurrent, superpotential situation, send audio alert simultaneously, and SMS notification staff can be sent keep in repair; Good stability of the present invention, is not easy to produce misoperation, and device protection is fully not easy to be burnt; This device can to current transformer moment transient state overvoltage, stable state the fault such as overvoltage all can enter guard mode fast.Make up other secondary over-voltage protector for current transformer only for single current transformer overvoltage protection.
Protection executive circuit of the present invention gathers the current delivery of current transformer to comparing circuits for triggering, judge whether to produce overcurrent, overvoltage, if produce the anomaly such as overvoltage, overcurrent, bidirectional triode thyristor Q5 conducting, by current transformer short circuit, protective current instrument transformer safety, avoids that voltage, electric current are excessive to be burnt; Can to current transformer moment transient state overvoltage, stable state the fault such as overvoltage all can enter guard mode fast.Make up other secondary over-voltage protector for current transformer only for single current transformer overvoltage protection.
The electric current that protection executive circuit receives processes by the circuits for triggering that compare of the present invention, a voltage signal is obtained after process, voltage signal and comparative voltage compare, and judge whether that voltage is excessive, thus judge whether current transformer produces overvoltage, overcurrent situations; Relatively circuits for triggering adopt and trigger high speed integrated power switch module, and highly sensitive, protection act is fast, and when module enters protection conducting state of a control instantaneously, it is more reliable and more stable that it exports control level.
Guard signal control circuit of the present invention receives the signal comparing circuits for triggering and transmit; if produce the abnormal conditions such as overvoltage, overcurrent; the bidirectional triode thyristor Q5 conducting of the electronic switch TWH8778 chip controls protection executive circuit of guard signal control circuit; by current transformer short circuit, protective current instrument transformer is not burnt.
The current conversion comparing circuits for triggering is the discernible signal of single-chip microcomputer by photoelectric isolating circuit of the present invention, by the signal transmission of overvoltage, overcurrent to single-chip microcomputer.
Single chip circuit controls SMS alarm circuit and sends SMS alarm, controls voice alarm module and carries out audio alert; The computer connecting circuit of single chip circuit can connect computer, by computer statistics, record, and can be printed by computer, facilitate the management of information to the overvoltage of current transformer, overcurrent information.
Voice alarm module can store and processed voice information, if current transformer produces overvoltage, overcurrent abnormality will send audio alert, notifies Field Force.
SMS alarm circuit can receive the instruction of single-chip microcomputer, send note to specific mobile phone, if current transformer produces overvoltage, overcurrent abnormality, SMS alarm circuit by by short message sending on the mobile phone of work of electric power system personnel, notify staff's on-call maintenance, make the present invention may be used for unattended transformer station.
The AC conversion of 220V is suitable direct current through processes such as step-down, rectification, filtering, for other circuit of the present invention provide power supply by power circuit access 220V alternating current.
Accompanying drawing explanation
Fig. 1 is operation principle schematic diagram of the present invention;
Fig. 2 is circuit connection diagram of the present invention;
Fig. 3 is installation connection diagram of the present invention;
In the accompanying drawings: 1, protect executive circuit, 2, compare circuits for triggering, 3, guard signal control circuit, 4, photoelectric isolating circuit, 5, single chip circuit, 6, voice alarm module, 7, SMS alarm circuit, 8, power circuit, 9, current collection circuit.
Embodiment
Below in conjunction with accompanying drawing, the present invention is described in further details:
There is the protector of current mutual inductor of remote short messages warning function, comprise current collection circuit 9, protection executive circuit 1, compare circuits for triggering 2, guard signal control circuit 3, photoelectric isolating circuit 4, power circuit 8, single chip circuit 5, SMS alarm circuit 7 and voice alarm module 6, current collection circuit 9 comprises ammeter A1, ammeter A2 and resistance R11, ammeter A1 connects the current transformer LA of A phase, and ammeter A2 connects B phase current mutual inductor LB; Ammeter A1 and ammeter A2 is connected in parallel resistance R11, resistance R11 connects and compares circuits for triggering 2, relatively circuits for triggering 2 connect guard signal control circuit 3, and guard signal control circuit 3 connects protection executive circuit 1, and protection executive circuit 1 connects current transformer LA summation current transformer LB; Relatively circuits for triggering 2 connect single chip circuit 5 by photoelectric isolating circuit 4, and single chip circuit 5 connects SMS alarm circuit 7 and voice alarm module 6 respectively; Power circuit 8 connects respectively and compares circuits for triggering 2, guard signal control circuit 3, single chip circuit 5, SMS alarm circuit 7 and voice alarm module 6.
Protection executive circuit 1 comprises ammeter A, resistance R11, bidirectional triode thyristor Q5, electric capacity C6, resistance R18, socket P2, protection executive circuit 1 is two cover circuit parallel with one another, wherein a set ofly be arranged on the current transformer LA of A phase, another set of circuit is arranged on the current transformer LB of B phase, two cover circuit structures and technical scheme identical, be described with the circuit wherein connecting A phase here; Ammeter A one end connects current transformer LA one end, and the other end connects the current transformer LA other end and bidirectional triode thyristor Q5 respectively, and bidirectional triode thyristor Q5 is connected by resistance R11 and compares circuits for triggering 2; Bidirectional triode thyristor Q5 is connected to the two ends of current transformer LA, can by current transformer LA short circuit during guarantee bidirectional triode thyristor Q5 conducting, and protective current instrument transformer LA is not burnt; Bidirectional triode thyristor Q5 is connected in parallel electric capacity C6 and resistance R18 respectively, and bidirectional triode thyristor Q5 connects guard signal control circuit 3 by diode D3 connection socket P2, socket P2.
Relatively circuits for triggering 2 comprise amplifier IC3, emitter follower Q2, resistance R5, amplifier IC3 form by by chip OPA2277 series resistor, and 3 pins of chip OPA2277 connect the ammeter A of protection executive circuit 1; Described emitter follower Q2 is connected in series by triode and resistance to form; Amplifier IC3 connects emitter follower Q2 by resistance R5; Emitter follower Q2 connects photoelectric isolating circuit 4, and emitter follower Q2 connects guard signal control circuit 3, and 5 pins of fortune chip OPA2277 connect the ammeter of stream collection and protection executive circuit 1, and 8 pins of chip OPA2277 connect power circuit 8.Amplifier IC3 also connects the emitter follower Q4 in parallel with emitter follower Q2, and emitter follower Q4 is identical with emitter follower Q2 structure, is used for the voltage of treatments B phase current mutual inductor LB.Have employed the amplifier that double operational OPA2277 (technotron) is imported, do Current Transformer Secondary open circuit, overcurrent, overvoltage amplifier testing circuit, make detection peak error voltage output accuracy, improve the speed of 2 times, extremely low input offset voltage, low input bias current, high common-mode rejection ratio and high detection amplify precision, have that good crosstalk is consistent and antijamming capability good.
Guard signal control circuit 3 comprises electronic switch IC1, triode Q14, triode Q12, socket P1, electric capacity C1, resistance R4, rheostat K1 and resistance R8, electronic switch IC1 is TWH8778 chip, 1 pin of electronic switch IC1 connects the emitter follower Q2 comparing circuits for triggering 2,2 pins, 3 pin serial connection of electronic switch IC1 pass through electric capacity C1 connecting triode Q14, triode Q14 is by resistance R8 connection socket P1, electric capacity C1 is by resistance R4 connecting triode Q12, triode Q12 connection socket P1; Socket P1 connects the socket P2 of protection executive circuit 1.Guard signal control circuit 3 also has with the guard signal control circuit 3 in parallel circuit identical with said structure, and comprising electronic switch is IC4, triode Q13, triode Q15, is used for the current transformer LB measured signal of treatments B phase.
Relatively the course of work of circuits for triggering 2 and guard signal control circuit 3 is: 3, the 5 pin current potentials of two input amplifier IC3 are greater than 2,6 pin current potentials; 1,7 pin export high level; R18, R28 are sample resistance, change the current signal exported for bis-times from current transformer LA, LB into voltage signal.OPA2277 and outer meeting resistance R11, R2, R5 and R20, R16, R15 form in-phase amplification circuit and are input to emitter follower Q2, Q4 conducting by after voltage signal amplification, trigger control end 5 pin of high speed integrated power switch module IC1, IC4.Power switching modules IC1, IC4 adopt TWH8778, and this modular peripheral element is few, cut without the need to debugging.Its 5 pin is control end, and when the voltage of this pin is greater than cut-in voltage 1.6V ~ 2V, electronic switch closes, 1,2 pin are connected.Disconnect lower than 1.6V switch module, when Q2, Q4 conducting, the pressure drop on R10, R24 makes 1,2 pin of TWH8778 connect; output protection control voltage; to the control trigger electrode of bidirectional triode thyristor Q5, Q7, enter conducting state instantaneously, thus short circuit current protection instrument transformer.
Bidirectional triode thyristor is BTA50-1000B, forward repetitive peak voltage 1000V, forward mean current rating 50A, controls pole trigger current and is less than 50mA, control pole trigger voltage 1.65V.Guard signal control circuit is 1 pin, 2 pin completes of IC1, IC4 while; 1 pin, 2 pin output voltage are added to the base stage of Q14, Q15 through potentiometer K1, K2 resistance R2, R8; make Q14, Q15 conducting; Q12, Q13 have base current; be in conducting state, the pressure drop on R10, R24 makes again the switch locking of TWH8778.The electrolytic capacitor of 470 μ F on Q14, Q15 collector electrode has longer discharge time constant, effectively can prevent the situation because of misoperation.
Photoelectric isolating circuit 4 comprises triode Q8, photoelectrical coupler U1, resistance R30 and resistance R31, the B collection of triode Q8 connects 5 pins comparing the amplifier IC3 of circuits for triggering 2, the C collection of triode Q8 connects 2 pins of photoelectrical coupler U1,1 pin of photoelectrical coupler U1 connects power circuit 8 by resistance R30,4 pins of photoelectrical coupler U1 connect single chip circuit 5,4 pins of photoelectrical coupler U1 connect power circuit 8 by resistance R31, the 3 pin ground connection of photoelectrical coupler U1.The current conversion comparing circuits for triggering 2 is the discernible signal of single-chip microcomputer in single chip circuit 5 by photoelectric isolating circuit 4, by the signal transmission of overvoltage, overcurrent to single-chip microcomputer.
Single chip circuit 5 comprises single-chip microcomputer IC5, chip IC 6, crystals vibrate device Y1, electric capacity C13, electric capacity C14, resistance R36 and computer connecting circuit, single-chip microcomputer IC5 is SCT89C52 single-chip microcomputer, chip IC 6 is X5045 chip, chip IC 6 connects power circuit 8, chip IC 6 connects single-chip microcomputer IC5, one end of crystals vibrate device Y1 connects the XTAL1 pin of single-chip microcomputer IC5 and by electric capacity C14 ground connection, the other end of crystals vibrate device Y1 connects the XTAL2 pin of single-chip microcomputer IC5 also by electric capacity C13 ground connection; Described computer connecting circuit comprises computer interface J1 and chip MA232, and 10 pins, 11 pins of single-chip microcomputer IC3 connect chip MA232, and chip MA232 connects computer interface J1; The INT pin of single-chip microcomputer IC3 connects 4 pins of the photoelectrical coupler U1 of photoelectric isolating circuit 4, and 4 pins of single-chip microcomputer IC3 connect voice alarm module 6, and 10 pins, 11 pins of single-chip microcomputer IC3 connect SMS alarm circuit 7.Single chip circuit 5 controls SMS alarm circuit 7 and sends SMS alarm, controls voice alarm module 6 and carries out audio alert; The computer connecting circuit of single chip circuit 5 can connect computer, by computer statistics, record, and can be printed by computer, facilitate the management of information to the overvoltage of current transformer, overcurrent information.
Described voice alarm module 6 comprises speech chip IC10, triode Q9, triode Q11, loud speaker LS1, resistance R38, resistance R40 and electric capacity C24, speech chip IC10 is SC020B chip, speech chip IC10 connects the single-chip microcomputer of single chip circuit 5 by triode Q9, speech chip IC10 connects triode Q11 by resistance R38, triode connects loud speaker LS1, loud speaker LS1 connecting triode Q9; Speech chip IC10 connects power circuit 8 by electric capacity C24, and triode Q11 connects power circuit 8 by resistance R40.Voice alarm module 6 can store and processed voice information, if current transformer produces overvoltage, overcurrent abnormality will send audio alert, notifies Field Force.
SMS alarm circuit 7 comprises gsm module, inductance L 1, SIM card, triode Q6, light-emitting diode D2, light-emitting diode D4 and light-emitting diode D5, gsm module is TC35i module, gsm module connects power circuit 8 by inductance L 1, gsm module connects SIM card, gsm module connecting triode Q6, triode Q6 connects power circuit 8 by light-emitting diode D2, and triode Q6 is connected the single-chip microcomputer IC5 of single chip circuit 5 with light-emitting diode D5 by the light-emitting diode D4 that is connected in parallel.SMS alarm circuit can receive the instruction of single-chip microcomputer, send note to specific mobile phone, if current transformer produce overvoltage, overcurrent abnormality, SMS alarm circuit 7 by by short message sending on the mobile phone of work of electric power system personnel, notify staff's on-call maintenance.
Power circuit 8 comprises mains switch S3, insurance F1, piezo-resistance R39, transformer T1, bridge rectifier D 7, filter circuit IC7, filter circuit IC8 and pressurizer IC11, mains switch S3 one end connects 220V power supply, the other end is respectively connected filter circuit IC7 and filter circuit IC8 with piezo-resistance R39 connection transformer T1, transformer T1 by bridge rectifier D 7 by insurance F1, filter circuit IC7 is that LM7806 chip is formed by inductance serial connection, and filter circuit IC7 connects and compares circuits for triggering 2, guard signal control circuit 3; Filter circuit IC8 is that LM7805 chip is formed by inductance serial connection, and filter circuit IC8 connects single chip circuit 5, voice alarm module 6, and connects SMS alarm circuit 7 by pressurizer IC11.Power circuit 8 accesses 220V alternating current, is suitable direct current, for other circuit of the present invention provide power supply through processes such as step-down, rectification, filtering by the AC conversion of 220V.Piezo-resistance R39 is used for absorbing the thunder and lightning of electric power system and various switching overvoltage, and it is large that R39 has powered-on capacity, and voltage range is wide, leakage current is little and the advantage such as fast response time, is optimal over-voltage protection element.Filter circuit IC8 exports the IC5 circuit supply that 5V voltage is single chip circuit; IC7 exports 6v voltage LM7806 and provides voltage for sampling protecting control circuit; the maximum electric current that can export 1A of IC7, IC8, connects the electric capacity of C19, a C11, has filtering and damping action after three terminal regulator.IC11 adopts AMS1117, for SMS alarm circuit 7, guard signal control circuit 3 provide 3.3V voltage.
The protector of current mutual inductor with remote short messages warning function of the present invention can carry out short-circuit protection to current transformer under current transformer produces overcurrent, superpotential situation; send audio alert simultaneously, and SMS notification staff can be sent keep in repair.