CN101860288B - Intelligent controller for three-phase motor - Google Patents
Intelligent controller for three-phase motor Download PDFInfo
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- CN101860288B CN101860288B CN2010101840662A CN201010184066A CN101860288B CN 101860288 B CN101860288 B CN 101860288B CN 2010101840662 A CN2010101840662 A CN 2010101840662A CN 201010184066 A CN201010184066 A CN 201010184066A CN 101860288 B CN101860288 B CN 101860288B
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Abstract
The invention discloses an intelligent controller for a three-phase motor. The intelligent controller for the three-phase motor comprises a magnetic latching relay K1, a positive-rotation magnetic latching relay K2, a positive-rotation magnetic latching relay K3, a negative-rotation magnetic latching relay K4, a negative-rotation magnetic latching relay K5 and a microprocessor, wherein the magnetic latching relay K1 is connected with a commercial power U phase and a motor U phase; the positive-rotation magnetic latching relay K2 is connected with a commercial power V phase and a motor V phase; the positive-rotation magnetic latching relay K3 is connected with a commercial power W phase and a motor W phase; the negative-rotation magnetic latching relay K4 is connected with the commercial power W phase and the motor V phase; the negative-rotation magnetic latching relay K5 is connected with the commercial power V phase and the motor W phase; the microprocessor makes the relays switched on through closed driving circuits and makes the relays switched off through open driving circuits; a V-phase channel state feedback circuit is connected with an interlocking circuit of the K2 and the K4; the interlocking circuit is connected with the closed driving circuit of the K2 and the K4; a W-phase channel state feedback circuit is connected with an interlocking circuit of the K3 and the K5; and the interlocking circuit is connected with the closed driving circuit of the K3 and the K5. The intelligent controller for the three-phase motor has the advantages of capacity of carrying a larger load, strong anti-interference capacity and stable and reliable operation.
Description
Technical field
The present invention relates to a kind of intelligent controller for three-phase motor.
Background technology
In modern society, three phase alternating current motor is widely used in various productive lifes field.Electric Machine Control is a maturation and the technology of extensive use.Make and break and rotating how to control motor have been very old topics.Present research is more prone to how can reasonably control motor, and its rate of failure is reduced, and makes its prolongation in useful life or the like aspect.The positive and negative rotating controller for motor of main flow is generally used solid-state relay at present, and by mechanical action, pure manual operations realizes the rotating of motor.
Solid-state relay SSR is a kind of mechanical movement that do not have, and does not contain the relay of moving parts.SSR is a kind of contactless switch element of all being made up of the solid-state electronic element, he utilizes the point of electronic devices and components, magnetic and light characteristic are finished input and the reliable isolation of exporting, utilize large power triode, power field effect pipe, the switching characteristic of device such as one-way SCR and bidirectional triode thyristor reaches contactless, switches on and off to no-spark controlled circuit.The life-span of solid-state relay is long, and is highly sensitive, and switching speed is fast.But tube voltage drop is big after its conducting, still have after semiconductor device turn-offs several microamperes in addition milliampere leakage current, the temperature characterisitic of electronic devices and components and the antijamming capability of electronic circuit are relatively poor.Therefore, it is little that the solid-state relay module is used for load more, and the occasion that electromagnetic interference is little is not suitable for big load motor control, the occasion bad adaptability more intense to electromagnetic interference.
Summary of the invention
Purpose of the present invention is exactly the problem of bringing with solid-state relay control alternating current machine in order to overcome, and proposes a kind of intelligent controller for three-phase motor, can be with bigger load, and antijamming capability is strong, and working stability is reliable.
For achieving the above object, intelligent controller for three-phase motor of the present invention, comprise that its contact connects civil power U phase and motor U magnetic latching relay K1 mutually, connect civil power V phase and motor V just commentaries on classics magnetic latching relay K2 mutually, connect civil power W phase and motor W just commentaries on classics magnetic latching relay K3 mutually, connect civil power W phase and motor V phase reversal magnetic latching relay K4, connect civil power V phase and motor W phase reversal magnetic latching relay K5, control microprocessor, magnetic latching relay K1 to K5 disconnects, closed drive circuit, motor channel status feedback circuit, motor V phase rotating magnetic latching relay K2, the K4 interlock circuit, motor W phase rotating magnetic latching relay K3, the K5 interlock circuit; Described magnetic latching relay K1 to K5 disconnects, closed drive circuit, the closed drive circuit of its each magnetic latching relay comprises the closed optocoupler of isolating, forward voltage applies circuit, control microprocessor is exported closed control signal and is isolated optocoupler through closure, forward voltage applies circuit and applies forward voltage to corresponding magnetic latching relay, its each magnetic latching relay disconnects drive circuit and comprises disconnection isolation optocoupler, reverse voltage applies circuit, control microprocessor output disconnects control signal and isolates optocoupler through disconnecting, reverse voltage applies circuit and applies reverse voltage to corresponding magnetic latching relay, motor V phase passage state-feedback circuit output feedback signal Sam1 is to motor V phase rotating magnetic latching relay K2, the K4 interlock circuit, the output of this interlock circuit connects magnetic latching relay K2, the closed drive circuit of K4, motor W phase passage state-feedback circuit output feedback signal Sam2 is to motor W phase rotating magnetic latching relay K3, the K5 interlock circuit, the output of this interlock circuit connects magnetic latching relay K3, the closed drive circuit of K5.
Above-mentioned control microprocessor is also imported feedback signal Sam1, Sam2, the Sam3 of motor three-phase channel status feedback circuit output.
In one embodiment, above-mentioned motor V phase rotating magnetic latching relay K2, the K4 interlock circuit, motor W phase rotating magnetic latching relay K3, the K5 interlock circuit, its arbitrary phase rotating magnetic latching relay interlock circuit comprises two two input logical circuits, one input of two two input logical circuits is connected to each other the feedback signal of this phase passage state-feedback circuit output of back input, another input is imported the closed control signal of this phase rotating magnetic latching relay of control microprocessor output respectively, and output connects the closure of the closed drive circuit of this phase rotating magnetic latching relay respectively and isolates the optocoupler input.Above-mentioned two input logical circuits can be selected two inputs and door for use.So that when making in the homophase rotating magnetic latching relay one closed, by logical circuit, feedback signal lost efficacy the input of the closed control signal of this phase rotating magnetic latching relay.
In another embodiment, above-mentioned motor V phase rotating magnetic latching relay K2, K4 interlock circuit, motor W phase rotating magnetic latching relay K3, K5 interlock circuit, its arbitrary phase rotating magnetic latching relay interlock circuit comprises the interlocking optocoupler, the forward voltage that the feedback signal input interlocking optocoupler of this phase passage state-feedback circuit output, the output of interlocking optocoupler are connected on the closed drive circuit of this phase rotating magnetic latching relay applies the power supply loop of circuit.So that when making in the homophase rotating magnetic latching relay one closed, the power supply that feedback signal makes this phase rotating magnetic latching relay forward voltage apply circuit can't insert.
Also can comprise zero cross detection circuit, this zero cross detection circuit comprises clamp circuit, voltage comparator, exports the square-wave signal of zero crossing saltus step to control microprocessor by the motor AC current signal of current transformer sampling output through clamp circuit, voltage comparator.
Also can comprise sample circuit, by the motor ac voltage signal input sampling circuit of voltage transformer sampling output, by the motor AC current signal input sampling circuit of current transformer sampling output, sample circuit output sampled data signal is to control microprocessor.In a kind of preferred implementation, above-mentioned sample circuit comprises voltage differential filtering, current-differencing filtering, sampling A, the sampling microprocessor, by the motor ac voltage signal of voltage transformer sampling output through voltage differential filtering input sample chip, by the motor AC current signal of current transformer sampling output through current-differencing filtering input sample chip, sampling A output sampled data signal is passed through the communication interface swap data to the microprocessor of sampling between sampling microprocessor and the control microprocessor.
Also can be provided with the communication interface of communicating by letter with Surveillance center, this communication interface connects microprocessor.Microprocessor through the communication interface outputting data signals to Surveillance center, Surveillance center's control command that the input communication interface receives.
The present invention adopts microprocessor, and the pure digi-tal control mode overcomes the shortcoming of mechanical analogue formula controller fully.The present invention adopts magnetic latching relay, and overcurrent capability is strong, can be with than heavy load.The inner mechanical structure that adopts of magnetic latching relay, antijamming capability is strong, and working stability is reliable.The present invention compares with the alternating current machine positive and negative rotating controller that present manual operations simulation is controlled, and very large superiority is arranged, and the present invention is provided with rotating magnetic latching relay interlock circuit, prevents that effectively relay from having little time to turn-off the power supply short circuit that causes.The present invention is provided with zero cross detection circuit, disconnects relay at current zero-crossing point, effectively reduces the generation of high pressure arcing.The present invention is provided with sample circuit, can export the power factor (PF) of each phase voltage current effective value, frequency and motor in the electrical network etc. in real time.In addition, the present invention also is provided with the communication interface of communicating by letter with Surveillance center, and as the RS485 bus communication, Zigbee radio communication and CAN bus communication by the communication interface of communicating by letter with Surveillance center, are formed the control networking, are used for many group Electric Machine Control.This is that the analog electric machine controller of common manual operations is incomparable.
Description of drawings
Fig. 1 is an embodiment three phase electric machine M rotating control schematic diagram;
Fig. 2 is an embodiment system configuration schematic block diagram;
Fig. 3 is an embodiment control microprocessor peripheral circuit schematic diagram;
Fig. 4 is that the embodiment magnetic latching relay disconnects, closed drive circuit schematic diagram;
Fig. 5 is an embodiment motor channel status feedback circuit schematic diagram;
Fig. 6 is the connection schematic diagram of embodiment voltage transformer pt 1, PT2, PT3;
Fig. 7 is that feedback signal Sam1, Sam2, the Sam3 of embodiment motor three-phase channel status feedback circuit output moves towards figure;
Fig. 8 is embodiment motor V phase rotating magnetic latching relay K2, the dual interlock circuit schematic diagram of K4;
Fig. 9 is that the embodiment zero cross detection circuit connects schematic block diagram;
Figure 10 is an embodiment zero cross detection circuit schematic diagram;
Figure 11 is the observed zero passage detection waveform of embodiment oscilloscope;
Figure 12 is an embodiment sample circuit schematic block diagram;
Figure 13 is an embodiment voltage sample schematic block diagram;
Figure 14 is an embodiment current sample schematic block diagram;
Figure 15 is an embodiment sampling A circuit diagram;
Figure 16 is embodiment voltage difference filter circuit figure;
Figure 17 is embodiment current-differencing filter circuit figure;
Figure 18 is embodiment RS485 communication interface circuit figure;
Figure 19 is that Embodiment C AN bus transceiver is realized circuit diagram;
Figure 20 is an embodiment ZigBee communication party block diagram;
Figure 21 is embodiment ZigBee level shifting circuit figure;
Figure 22 is that embodiment E EPROM realizes circuit diagram.
Embodiment
Be described in detail below in conjunction with the CONSTRUCTED SPECIFICATION of accompanying drawing the embodiment of the invention.
As Fig. 1, shown in Figure 2, the embodiment of the invention, comprise that its contact connects civil power U phase and motor U magnetic latching relay K1 mutually, connect civil power V phase and motor V just commentaries on classics magnetic latching relay K2 mutually, connect civil power W phase and motor W just commentaries on classics magnetic latching relay K3 mutually, connect civil power W phase and motor V phase reversal magnetic latching relay K4, connect civil power V phase and motor W phase reversal magnetic latching relay K5, control microprocessor, magnetic latching relay K1 to K5 disconnects, closed drive circuit, motor three-phase channel status feedback circuit, motor V phase rotating magnetic latching relay K2, the dual interlock circuit of K4, motor W phase rotating magnetic latching relay K3, the dual interlock circuit of K5, zero cross detection circuit, sample circuit, and the communication interface of communicating by letter with Surveillance center.Magnetic latching relay K1 to K5 disconnects, closed drive circuit, the closed drive circuit of its each magnetic latching relay comprises the closed optocoupler of isolating, forward voltage applies circuit, control microprocessor is exported closed control signal and is isolated optocoupler through closure, forward voltage applies circuit and applies forward voltage to corresponding magnetic latching relay, its each magnetic latching relay disconnects drive circuit and comprises disconnection isolation optocoupler, reverse voltage applies circuit, and control microprocessor output disconnects control signal and isolates optocoupler through disconnecting, reverse voltage applies circuit and applies reverse voltage to corresponding magnetic latching relay.Motor V phase passage state-feedback circuit output feedback signal Sam1 is to motor V phase rotating magnetic latching relay K2, the dual interlock circuit of K4, the output of this interlock circuit connects magnetic latching relay K2, the closed drive circuit of K4, motor W phase passage state-feedback circuit output feedback signal Sam2 is to motor W phase rotating magnetic latching relay K3, the dual interlock circuit of K5, the output of this interlock circuit connects magnetic latching relay K3, the closed drive circuit of K5, the feedback signal Sam1 of motor three-phase channel status feedback circuit output, Sam2, Sam3 also delivers to control microprocessor.Motor AC current signal by current transformer sampling output is exported the square-wave signal of zero crossing saltus step to control microprocessor through the zero passage testing circuit.Sample circuit comprises sampling A, sampling microprocessor, by the motor ac voltage signal of voltage transformer sampling output, by the motor AC current signal of current transformer sampling output through sampling A output sampled data signal to the microprocessor of sampling, the sampling microprocessor is by CAN communication interface and control microprocessor swap data.Microprocessor through RS485 communication interface, ZigBee wireless communication interface, CAN communication interface outputting data signals to Surveillance center, Surveillance center's control command that the input communication interface receives.
As shown in Figure 2, present embodiment adopts dual micro processor, passes through the collaborative work of CAN communication interface between two microprocessors.Control microprocessor is responsible for the control of magnetic latching relay K1 to K5, RS485 communication and ZigBee radio communication.The sampling microprocessor is responsible for three-phase voltage, electric current, frequency, power factor (PF) and meritorious idle measurement, and the protection of overvoltage, under-voltage, phase shortage and overcurrent.The power down memory module is used for storing the address of every microprocessor, the electric energy that load motor consumes, and be used for judging and parameters calculated.When system's power down, these parameters are stored among the EEPROM, and system powers on once more, and these parameters are read again.Dual interlock circuit is independent of microprocessor, and its operating state is not subjected to the control of microprocessor, and only the folding condition with relay is relevant.Dual interlock circuit prevents to bump the generation of phase effectively.Zero cross detection circuit detects the zero point of alternating current, and the notice processor controls, cuts off zero point, reduces and avoid the generation of arcing.The voltage and current instrument transformer is used for taking a sample from electrical network, and sampling voltage and electric current are respectively applied for detection, zero passage detection.The sampling microprocessor reads measured value from sampling A, carry out analytical calculation and handle, and judge abnormality, if note abnormalities, then notifies control microprocessor to carry out rupturing operation immediately.
As shown in Figure 1, the present invention is by exchanging the rotating control of the two-phase realization three phase electric machine M in the three-phase arbitrarily.Wherein, K1, K2, K3, K4 and K5 are five magnetic latching relays.As K1, K2, when K3 is closed, phase sequence is: U, V, W, this moment, motor M was just changeed.As K1, K4, when K5 is closed, phase sequence is: U, W, V, motor M counter-rotating this moment.
The present invention requires to be with high power load, therefore selects magnetic latching relay for use, adopts Shanghai ten thousand good WJ302 type magnetic latching relays.Nominal load 100A/240VAC, coil control voltage DC12V.General appliance life 10000 times, mechanical endurance 1000000 times, the maximum 2m Ω of contact contact resistance.Therefore, have power saving, stable performance, volume is little, bearing capacity is big, than the characteristics of general electromagnetic relay superior performance.
Its contact opening and closing state of magnetic latching relay is that the magnetic force that is produced by permanent-magnet steel is kept at ordinary times.When the contact of relay need be opened or be closed state, when promptly switching on or off load, only need just using or anti-dc pulse voltage excitation coil, relay has just been finished the state exchange of opening and closing in moment.At this moment power loss is generally less than 1W.When usually the contact was in hold mode, coil need not continue energising, and it is constant to only depend on the magnetic force of permanent-magnet steel just can keep the state of relay.
Control microprocessor and sampling microprocessor are all chosen 8 single-chip microcomputers of 78K0 series of NEC electronics, and the single-chip microcomputer model is uPD78F0881.This single-chip microcomputer comprises 32K Flash program storage, 1K high-speed RAM.The maximum 20M crystal oscillator of supporting.Built-in 48 bit timing devices and 2 16 bit timing devices.Communications portion comprises dual serial port and a CAN port, built-in CAN controller.Chip integration become to power on zero clearing POC circuit and low voltage detector LVI.
As shown in Figure 3, be control microprocessor peripheral circuit schematic diagram, wherein LED1, LED2, LED3 just the is respectively indicator light that changes, shuts down, reverses.
As shown in Figure 4, utilizing the H bridge circuit to drive the disconnected of magnetic latching relay closes, because the contacts status of magnetic latching relay is kept by the magnetic force of permanent-magnet steel, therefore, when change the control contact, only need just can realize switching on or off of magnetic latching relay in the DC pulse forward or backwards of coil two ends input certain width.The closed drive circuit of magnetic latching relay comprises closed isolation optocoupler GA, forward voltage applies circuit, forward voltage applies circuit and is made up of triode Q1, Q4 and resistance R 1, control microprocessor is exported closed control signal CtrlA and is applied circuit and apply the coil of forward voltage to magnetic latching relay K through closure isolation optocoupler GA, forward voltage, makes the closing of contact of magnetic latching relay K.Magnetic latching relay disconnection drive circuit comprises disconnection isolation optocoupler GB, reverse voltage applies circuit, reverse voltage applies circuit and is made up of triode Q2, Q3 and resistance R 2, control microprocessor output disconnects control signal CtrlB and applies circuit and apply the coil of reverse voltage to magnetic latching relay K through disconnection isolation optocoupler GB, reverse voltage, and the contact of magnetic latching relay K is disconnected.The concrete course of work is: when CtrlA is a high level, and when CtrlB is low level, Q1 and Q4 conducting, time-delay 100ms, zero clearing CtrlA forms the positive pulse driving relay K closure of 12V, 100ms pulsewidth.When CtrlA is a low level, when CtrlB is high level, Q2 and Q3 conducting, time-delay 100ms, zero clearing CtrlB, the back pulse that forms 12V, 100ms pulsewidth drives relay K and disconnects.
As seen, magnetic latching relay can make its closure for the 12V positive pulse of its 100ms pulsewidth, after its closure, will keep the state of this closure always, when giving the 12V negative pulse of its 100ms pulsewidth, can make its disconnection.The 12V positive negative pulse stuffing of 100ms is by the IO mouth control of single-chip microcomputer, and Ctrl A and CtrlB are single-chip microcomputer IO mouth output.As Ctrl A=1, during Ctrl B=0, closed isolation optocoupler GA conducting disconnects isolation optocoupler GB and ends, this moment triode Q1 and Q4 conducting, Q2 and Q3 end, and the RelayA end is about 12V, and the RelayB end is about 0V, at this moment, relay is a forward conduction, so relay can be closed.Otherwise as Ctrl A=0, during Ctrl B=1, relay can disconnect.
As shown in Figure 5, motor channel status feedback circuit comprises voltage transformer, instrument amplifier AD623, current rectifying and wave filtering circuit, voltage comparator LM339.U, the voltage of U ' for obtaining from voltage transformer secondary sample resistance two ends, instrument amplifier AD623 has high input impedance, is mainly used in raising input impedance herein, and plays the effect of isolation.The differential voltage signal of voltage transformer secondary is by instrument amplifier AD623, through the halfwave rectifier filter circuit, become pulsating direct current, halfwave rectifier is after the RC filter circuit, obtain an approximate galvanic current and press signal, threshold voltage by voltage comparator LM339 and setting compares at last, output feedback signal Sam.
Through test, when the former limit of voltage transformer added the 380V alternating voltage, secondary output effective value was the AC signal of 0.44V, and behind rectifying and wave-filtering, direct current signal is approximately 0.37V.When the former limit of voltage transformer added (380*30%) V alternating voltage, secondary output effective value was the AC signal of 0.33V, and behind rectifying and wave-filtering, direct current signal is approximately 0.28V.Therefore, threshold signal is set to 0.28＜Vo＜0.37.That is, when the V of measurement signal voltages≤(380*30%), feedback signal Sam state does not overturn.Choosing threshold voltage is 0.30V.
Motor three-phase channel status feedback circuit is provided with No. three motor channel status feedback circuits, obtains voltage from the sample resistance two ends of voltage transformer pt 1, PT2, PT3 secondary respectively.As shown in Figure 6, the former limit of voltage transformer pt 1 is connected between motor U phase, the V phase, survey the line voltage between the UV, the former limit of voltage transformer pt 2 is connected between motor U phase, the W phase, survey the line voltage between the UW, the former limit of voltage transformer pt 3 is connected between motor V phase, the W phase, surveys the line voltage between the VW.Voltage transformer pt 1 corresponding feedback signal Sam1, voltage transformer pt 2 corresponding feedback signal Sam2, voltage transformer pt 3 corresponding feedback signal Sam3.Under the whole disconnection of magnetic latching relay, Sam1=Sam2=Sam3=1.
Because loop, the former limit of voltage transformer is connected on the magnetic latching relay output, works as relay closes, in the time of the conducting of three-phase path, feedback signal is output as low level.When the relay disconnection, output end voltage is zero, and feedback signal is output as high level.In fact feedback signal has reflected the on off operating mode of three-phase passage.
On program, always allow U at first closed mutually, just changeing closed K1, K2, K3, closed K1, K4, K5 reverse.
When the U closure, when V, W are all not closed, this moment UV=UW ≈ 190V, VW=0V can not make the feedback signal upset.This moment feedback signal Sam1=Sam2=Sam3=1.
Work as U, the V closure, when W also is not able to do in time closure, this moment UV=380V, UW=VW ≈ 190V.Then, by the feedback signal Sam1=0 that PT1 obtains, Sam2=Sam3=1.At this moment, feedback signal Sam1 upset illustrate that K2 or K4 are closed, and pin K4 or K2 this moment, makes it can't closure.
In like manner, work as U, the W closure, when V also is not able to do in time closure, this moment UW=380V, UV=VW ≈ 190V.Then, by the feedback signal Sam2=0 that PT2 obtains, Sam1=Sam3=1.At this moment, feedback signal Sam2 upset illustrate K3 or K5 closure, and pin K5 or K3 this moment, makes it can't closure.
Work as U, when V, W are all closed, UV=VW=UW=380V.Sam1＝Sam2＝Sam3＝0。This moment, feedback signal Sam1 and Sam2 were all locked with corresponding relays.
As seen, under the closed mutually situation of U, feedback signal Sam1 has reflected motor V phase channel status, and corresponding feedback circuit is a motor V phase passage state-feedback circuit.Feedback signal Sam2 has reflected motor W phase channel status, and corresponding feedback circuit is a motor W phase passage state-feedback circuit.
As shown in Figure 7, reacted the on off operating mode of motor three-phase passage because of feedback signal Sam1, Sam2, the Sam3 of motor three-phase channel status feedback circuit output, so all send into the I/O mouth of control microprocessor MCU single-chip microcomputer, the on off operating mode of three-phase passage is informed single-chip microcomputer, and whether single-chip microcomputer is judged the control of relay successful on this basis.Feedback signal Sam1, Sam2 also participate in interlocking simultaneously, feedback signal Sam1 input motor V phase rotating magnetic latching relay K2, the dual interlock circuit of K4, feedback signal Sam2 input motor W phase rotating magnetic latching relay K3, the dual interlock circuit of K5.
If after sending close command, the three-phase closed action all is finished, as long as detecting, the control microprocessor single-chip microcomputer have any one signal condition still to be " 1 " in the feedback signal, then carry out immediately and cut off instruction, single-chip microcomputer resets simultaneously.
Interlocking is that two relays lock mutually, and when one of them relay closes, the another one relay necessarily can't move.Embodiment prevents that by dual interlock circuit two rotating magnetic latching relay K2, K4 or K3, K5 are closed simultaneously.
As shown in Figure 8, motor V phase rotating magnetic latching relay K2, the dual interlock circuit of K4, comprise two two input logical circuits and door F, F ', voltage follower T and interlocking optocoupler GS, two two input logical circuits and a door F, the input of F ' is connected to each other the feedback signal Sam1 of back input motor V phase passage state-feedback circuit output, another input is imported the V phase rotating magnetic latching relay K2 of control microprocessor output respectively, the closed control signal CtrlA of K4, CtrlA ', output connects the closed optocoupler GA that isolates respectively, the input of GA ', feedback signal Sam1 is also through voltage follower T input interlocking optocoupler GS, and the output of interlocking optocoupler GS is connected on power supply end 12V and the closed optocoupler GA that isolates that forward voltage applies circuit, between the feeder ear of GA '.
As shown in Figure 8: comprise two relay K 2, K4 drive circuit among the figure, for needing two parts of interlocking.Wherein voltage follower T isolates between feedback signal Sam1 and the interlocking optocoupler GS, and changes the input impedance in this loop, avoids feedback signal Sam1 to be dragged down by interlocking optocoupler GS.
A, when two relay K 2 wherein, when K4 is in off-state: feedback signal Sam1=1.
What this moment, Ctrl A and Ctrl A ' held all is in open state with door F, F '; And interlocking optocoupler GS conducting.12V adds to optocoupler GA and optocoupler GA ' by interlocking optocoupler GS.At this moment, two relay K 2, K4 all can be free closed.
B, after wherein any one relay K 2 or K4 closure, feedback signal Sam1=0.
All being pinned of Ctrl A and Ctrl A ' end this moment by the Sam1 signal with door F, F '.Regardless of the state of CtrlA and Ctrl A ' end, be low level with door F, F ' output.Therefore optocoupler GA and optocoupler GA ' end.Because the Sam1 signal is a low level, voltage follower T output low level makes interlocking optocoupler GS end again.The 12V power supply of optocoupler GA and optocoupler GA ' is cut off.That is: two-way relay K 2, the K4 that is locked all can't carry out closed action again.Up to carrying out open command, feedback signal Sam1 is high level again.
Motor W phase rotating magnetic latching relay K3, the dual interlock circuit of K5 and motor V phase rotating magnetic latching relay K2, the dual interlock circuit of K4 are identical, at this moment, input be the feedback signal Sam2 of W phase passage state-feedback circuit output.
Dual interlock circuit shown in Figure 8 prevents that by two aspects two rotating magnetic latching relays are closed simultaneously:
1,, make closure isolation optocoupler GA, the GA ' input of the closed drive circuit of rotating magnetic latching relay can't put 1 by two two inputs and door F, F '.Just when one of them relay closes, feedback signal makes the closed input of isolating optocoupler lose efficacy.
2, by voltage follower T and interlocking optocoupler GS, make closed optocoupler GA, the GA ' of isolating can't insert the 12V power supply, relay can't obtain the driving pulse of 12V.Just when one of them relay closes, feedback signal disconnects closed 12V power supply of isolating optocoupler GA, GA '.The embodiment feedback signal disconnects closed 12V power supply of isolating optocoupler GA, GA ', the 12V power supply that need also can be designed so that the two-way relay forward voltage of interlocking to apply circuit disconnects, the 12V power supply that is designed so that triode Q1, Q1 ' disconnects or the like, in a word, as long as the output of interlocking optocoupler GS is connected on needs the two-way of interlocking relay forward voltage to apply the power supply loop of circuit, the 12V power supply can't be inserted get final product.
The benefit of this interlock circuit is a duplicate protection, not only accomplishes interlocking at control microprocessor output IO end.Even the IO interlocking was lost efficacy, back level interlocking can also play a role.
In the switching device on-off circuit, when voltage is not less than 10～20V, electric current is not less than 80～100mA, just can produce electric arc between the contact of switching device.Electric arc is the free gas of high temperature high conductivity, and it not only has the destruction that can reach to contact, and makes the time lengthening of open circuit.As a kind of high power switch, will produce electric arc during the magnetic latching relay switch, thereby influence stability of the present invention and useful life.For avoiding the generation of electric arc in switching process, the disconnection of control relay when being chosen in electric current and being zero, the condition that electric arc is produced does not possess.Therefore, the control actuating of relay will be a kind of effective ways of avoiding producing electric arc when the detection electric current is zero.
As shown in Figure 9, current transformer CT meets load RL, converts current signal to voltage signal.Be used for zero passage detection on the one hand, be used on the one hand measuring.Because measure portion input impedance is low, follows output so be used for the signal of zero passage detection by instrument amplifier AD623, improve the input impedance of zero passage detection part.Simultaneously signal and measure portion are isolated.The sinusoidal signal of current transformer output is shaped as the standard square wave through behind the zero cross detection circuit, delivers to the external interrupt mouth of control microprocessor.
As shown in figure 10, zero cross detection circuit comprises clamp circuit, voltage comparator, exports the square-wave signal of zero crossing saltus step to control microprocessor by the motor AC current signal of current transformer CT sampling output through instrument amplifier AD623, clamp circuit, voltage comparator.The course of work is: the sine voltage signal of getting from sample resistance RL two ends through voltage stabilizing didoe D1, D2 clamper, makes signal be lower than 5.1V.Deliver to in-phase end and the end of oppisite phase of four voltage comparator LM339.The in-phase end of LM339 is represented with "+", and inverting input is with "-" expression.When making comparisons two voltages, any one input adds a fixed voltage and does reference voltage, is also referred to as threshold level, and it can select any point of LM339 input common-mode range, and the other end adds a signal voltage to be compared.When "+" terminal voltage was higher than "-" end, efferent duct ended, and was equivalent to the output open circuit.When "-" terminal voltage was higher than "+" end, efferent duct was saturated, is equivalent to export the termination electronegative potential.Two input terminal voltage difference just can guarantee that greater than 10mV output can be transformed into another kind of state reliably from a kind of state, and therefore, it is more satisfactory LM339 being used in occasion such as Testing of Feeble Signals.The output of LM339 is equivalent to a transistor that does not connect collector resistance, and output generally must connect a resistance to positive supply in use, is called pull-up resistor, selects 3-15K.Select the pull-up resistor of different resistances can influence the value of output high potential.Because when output transistor ended, its collector voltage depended on the value of pull-up resistor and load basically.As shown in figure 11, be the viewed zero passage detection waveform of oscilloscope.Because LM339 two input pressure reduction are greater than 10mV, its output just can be from a kind of state-transition to another kind of state.Therefore, when the current transformer output signal was big more, it is accurate more that detect zero point.Among the figure, sinusoidal signal is the current transformer signal output waveform, and square wave is a voltage comparator LM339 output waveform.As can be seen, the trailing edge of square wave almost coincide with the sinusoidal ac signal zero crossing.
As shown in figure 12, sample circuit comprises voltage differential filtering, current-differencing filtering, sampling A, sampling microprocessor, by the motor ac voltage signal of voltage transformer pt sampling output through voltage differential filtering input sample chip, through current-differencing filtering input sample chip, sampling A output sampled data signal is to the microprocessor of sampling by the motor AC current signal of current transformer CT sampling output.
Sampling A adopts the watt metering chip ATT7022A of Zhuhai torch power company.
ATT7022A is the special-purpose computation chip of a kind of high accuracy three-phase electric energy, is applicable to the application of phase three-wire three and three-phase and four-line.ATT7022A the is integrated circuit such as Digital Signal Processing of six road second order sigma-delta ADC, reference voltage circuit and all power, energy, effective value, power factor (PF) and frequency measurement.ATT7022A provides a SPI interface, carries out the transmission of measuring parameter and calibration parameter between convenience and the external microprocessor.All measuring parameters can be read by the SPI interface.
As shown in figure 13, voltage sampling signal is exported from voltage transformer pt, and voltage transformer pt adopts epoxy sealing current mode voltage transformer TV19E.Sample through the direct input sample chip of differential filtering circuit from the small-signal that voltage transformer pt comes out.The voltage transformer pt output signal is divided into two-way, and one the tunnel is used to produce feedback signal, and shown in the figure dotted line, another road is used for measuring, shown in the figure solid line.Totally three groups of same harvesters of three-phase voltage passage is measured three-phase voltage respectively, and the sampling microprocessor reads the voltage sample value by the SPI interface, and judges whether to exist phenomenons such as under-voltage, overvoltage and phase shortage by calculating.If above abnormal conditions then send to control microprocessor immediately by the CAN bus and cut off order immediately, load motor is protected.
As shown in figure 14, current sampling signal is a current transformer CT output signal, and current transformer CT output signal is divided into two-way, and one the tunnel is used for zero passage detection, and shown in the figure dotted line, the one tunnel is used for measuring, shown in the figure solid line.Totally three groups of same harvesters of three-phase current passage is measured three-phase current respectively, and the sampling microprocessor communicates by SPI interface and sampling A ADT7022A, reads sampled value, and size and variation tendency by electric current in the computational analysis electrical network.Surpass the setting rated current if record electric current, then will enter guard mode, the sampling microprocessor sends to cut off immediately to control microprocessor by the CAN bus and orders.
As shown in figure 15, realize voltage, current measurement circuit figure for sampling A.As shown in figure 16, be voltage difference filter circuit figure, as shown in figure 17, be current-differencing filter circuit figure, only draw one road voltage sample passage and one road current sample passage, Uv, Uv ' and Ui, Ui ' is respectively the differential signal that voltage transformer summation current transformer sample resistance two ends are got, and differential signal is sampled by filter network input sample chip.
The present invention is provided with the communication interface of communicating by letter with Surveillance center, can reflect the ruuning situation of equipment by communication interface in real time to the user, and simultaneously the information that also can be as required sends with equipment of user feeds back to the present invention with control command.Communication mode of the present invention is flexible, has designed the needs that multiple communication interfaces such as RS485 communication interface, CAN communication interface, ZigBee wireless communication interface satisfy information exchange.Below introduce various communication interfaces in detail.
1) RS485 communication
RS485 adopts the differential signal negative logic ,+2V～+ 6V represents " 0 " ,-6V～-2V represents " 1 ".RS485 has two-wire system and two kinds of wiring of four-wire system, four-wire system can only realize point-to-point communication mode, existing seldom employing, and many employings is the two-wire system mode of connection now, this mode of connection is the bus type topological structure, can articulate 32 nodes on same bus at most.General employing is the master-slave communication mode in the RS485 communication network, i.e. a plurality of slaves of main frame band.
RS485 communication of the present invention adopts MAX3082 to realize.Peripheral circuit as shown in figure 18.
2) CAN communication
The CAN bus is the communication network of walking of distributed control of a kind of effective support and control in real time.Short frame structure is adopted in CAN communication, and each frame is 8 bytes, and has adopted functions such as position filling, data block coding, CRC check, and the data error rate is extremely low.CAN is unique so far fieldbus that international standard is arranged, or adopts the work of many master modes, and the direct communication distance can reach 10km farthest, and speed is under 5kbps, and traffic rate reaches as high as 1Mbps.
The realization of CAN bus communication mainly comprises the content of two aspects: one is the design of CAN controller; Another is exactly the interface CAN transceiver of realizing between CAN controller and the external physical bus.
(1) CAN bus control unit
Can directly use the inner integrated CAN bus control unit of NEC single-chip microcomputer uPD78F0881 for controller, only necessary parameter need be set can use.This module satisfies ISO11898 CAN bus communication protocol; Forgive standard frame and two kinds of working methods of expansion frame; Have 16 functional characteristics such as data buffer area.Can satisfy the demand well.
(2) CAN bus transceiver
What this module was selected for use is that the TJA1050 chip that Philips company produces drives bus circuit.This device provide between CAN controller and the physical bus interface and to the differential transmission and the receiving function of CAN bus.
Realize circuit as shown in figure 19.
3) ZigBee communication
ZigBee is a kind of emerging short distance, low rate radio network technique, and it is a kind of technical scheme between radio mark technology and bluetooth.Being mainly used near radio connects.It has the radio standard of oneself, coordinates to realize communication between thousands of small transducers mutually.These transducers only need energy seldom, by radio wave data are passed to another transducer from a transducer in the mode of relay, so their communication efficiency is very high.
ZigBee communication party block diagram of the present invention as shown in figure 20.
Used Zigbee module is the 3.3V electric power system in this module, and microprocessor is the 5V electric power system, for the microcontroller serial port signal level being converted to the operable level of Zigbee module, therefore between microprocessor and Zigbee, need add the one-level level shifting circuit.
Level shifting circuit as shown in figure 21.
When signal is transmitted to the Zigbee module by serial ports, shown in the left figure of Figure 21, when signal is the 5V level, the Q7.1 conducting, Q7.2 ends, and output level is the 3.3V level; When signal was low level, Q7.1 ended, the Q7.2 conducting, and output level is low.Vice versa, shown in the right figure of Figure 21.
Vdd is 3.3V, and Vcc is 5V, and TOUT links to each other with microcontroller serial port with TIN, and ZigTx links to each other with the ZigBee module with ZigRx.
Storage of the present invention adopts the EEPROM storage chip.Under the situation of power down, preservation data that still can be complete.Repeating erasable number of times is 100,000 times.In this design, EEPROM is used for preserving the address of every single-chip microcomputer, and the ID of CAN node, judges electric energy that threshold values and motor consumed of protection or the like at relay actuation time.Total storage data volume is little, therefore select for use the 24C02 of 256 bytes as memory cell, communicate by letter by iic bus between 24C02 and the single-chip microcomputer, it realizes circuit as shown in figure 22, SCL links to each other with single-chip microcomputer respectively with SDA, SCL is the clock line of iic bus, and SDA is a data wire, and single-chip microcomputer is erasable by Simulation with I IC program, read EEPROM.
In sum, intelligent controller for three-phase motor forceful electric power of the present invention and control circuit are partly isolated, light-emitting diode indication forward and backward state, and communication mode is flexible, can conveniently realize the switching to the operation of three phase electric machine forward and backward.Be provided with functions such as interlocking, zero passage detection, handover security is reliable, does not have, spark noiselessness during switching.Product is mainly used in the switching of high-power threephase motor rotating operation.
Embodiments of the present invention are not limited thereto; according to foregoing of the present invention; ordinary skill knowledge and customary means according to this area; do not breaking away under the above-mentioned basic fundamental thought of the present invention prerequisite; can also make modification, replacement or the change of other various ways, all drop within the rights protection scope of the present invention.
Claims (5)
1. intelligent controller for three-phase motor, it is characterized in that: comprise that its contact connects civil power U phase and motor U magnetic latching relay K1 mutually, connect civil power V phase and motor V just commentaries on classics magnetic latching relay K2 mutually, connect civil power W phase and motor W just commentaries on classics magnetic latching relay K3 mutually, connect civil power W phase and motor V phase reversal magnetic latching relay K4, connect civil power V phase and motor W phase reversal magnetic latching relay K5, control microprocessor, magnetic latching relay K1 to K5 disconnects, closed drive circuit, motor channel status feedback circuit, motor V phase rotating magnetic latching relay K2, the K4 interlock circuit, motor W phase rotating magnetic latching relay K3, the K5 interlock circuit; Described magnetic latching relay K1 to K5 disconnects, closed drive circuit, the closed drive circuit of its each magnetic latching relay comprises the closed optocoupler of isolating, forward voltage applies circuit, control microprocessor is exported closed control signal and is isolated optocoupler through closure, forward voltage applies circuit and applies forward voltage to corresponding magnetic latching relay, its each magnetic latching relay disconnects drive circuit and comprises disconnection isolation optocoupler, reverse voltage applies circuit, control microprocessor output disconnects control signal and isolates optocoupler through disconnecting, reverse voltage applies circuit and applies reverse voltage to corresponding magnetic latching relay, motor V phase passage state-feedback circuit output feedback signal Saml is to motor V phase rotating magnetic latching relay K2, the K4 interlock circuit, the output of this interlock circuit connects magnetic latching relay K2, the closed drive circuit of K4, motor W phase passage state-feedback circuit output feedback signal Sam2 is to motor W phase rotating magnetic latching relay K3, the K5 interlock circuit, the output of this interlock circuit connects magnetic latching relay K3, the closed drive circuit of K5;
Described motor V phase, W phase passage state-feedback circuit, its arbitrary motor channel status feedback circuit comprises voltage transformer, current rectifying and wave filtering circuit, voltage comparator, the voltage signal of voltage transformer secondary is through current rectifying and wave filtering circuit, voltage comparator output feedback signal, the former limit of the voltage transformer pt 1 of motor V phase passage state-feedback circuit is connected between motor U phase, the V phase, and the former limit of the voltage transformer pt 2 of motor W phase passage state-feedback circuit is connected between motor U phase, the W phase;
The former limit that is provided with voltage transformer pt 3 is connected motor V phase, the W motor channel status feedback circuit between mutually, output feedback signal Sam3, and described feedback signal Sam1, Sam2, Sam3 all import control microprocessor;
Zero cross detection circuit, this zero cross detection circuit comprises clamp circuit, voltage comparator, exports the square-wave signal of zero crossing saltus step to control microprocessor by the motor AC current signal of current transformer sampling output through clamp circuit, voltage comparator;
Sample circuit, by the motor ac voltage signal input sampling circuit of voltage transformer sampling output, by the motor AC current signal input sampling circuit of current transformer sampling output, sample circuit output sampled data signal is to control microprocessor; Sample circuit comprises voltage differential filtering, current-differencing filtering, sampling A, sampling microprocessor, by the motor ac voltage signal of voltage transformer sampling output through voltage differential filtering input sample chip, by the motor AC current signal of current transformer sampling output through current-differencing filtering input sample chip, sampling A output sampled data signal is passed through the communication interface swap data to the microprocessor of sampling between sampling microprocessor and the control microprocessor.
2. controller according to claim 1, it is characterized in that: described motor V phase rotating magnetic latching relay K2, the K4 interlock circuit, motor W phase rotating magnetic latching relay K3, the K5 interlock circuit, its arbitrary phase rotating magnetic latching relay interlock circuit comprises two two input logical circuits, one input of two two input logical circuits is connected to each other the feedback signal of this phase passage state-feedback circuit output of back input, another input is imported the closed control signal of this phase rotating magnetic latching relay of control microprocessor output respectively, and output connects the closure of the closed drive circuit of this phase rotating magnetic latching relay respectively and isolates the optocoupler input.
3. controller according to claim 1, it is characterized in that: described motor V phase rotating magnetic latching relay K2, K4 interlock circuit, motor W phase rotating magnetic latching relay K3, K5 interlock circuit, its arbitrary phase rotating magnetic latching relay interlock circuit comprises the interlocking optocoupler, the forward voltage that the feedback signal input interlocking optocoupler of this phase passage state-feedback circuit output, the output of interlocking optocoupler are connected on the closed drive circuit of this phase rotating magnetic latching relay applies the power supply loop of circuit.
4. controller according to claim 1, it is characterized in that: described motor V phase rotating magnetic latching relay K2, the K4 interlock circuit, motor W phase rotating magnetic latching relay K3, the K5 interlock circuit, its arbitrary phase rotating magnetic latching relay interlock circuit comprises two two input logical circuits, voltage follower and interlocking optocoupler, one input of two two input logical circuits is connected to each other the feedback signal of this phase passage state-feedback circuit output of back input, another input is imported the closed control signal of this phase rotating magnetic latching relay of control microprocessor output respectively, output connects the closure of the closed drive circuit of this phase rotating magnetic latching relay respectively and isolates the optocoupler input, the feedback signal of this phase passage state-feedback circuit output is also through voltage follower input interlocking optocoupler, and the forward voltage that the output of interlocking optocoupler is connected on the closed drive circuit of this phase rotating magnetic latching relay applies the power supply loop of circuit.
5. according to each described controller of claim 1 to 4, it is characterized in that: also be provided with the communication interface of communicating by letter with Surveillance center, this communication interface connects microprocessor.
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| CN102332851B (en) * | 2011-08-23 | 2013-10-09 | 中国北车股份有限公司大连电力牵引研发中心 | Forward/reverse interlocking device of motor |
| CN102354404B (en) * | 2011-10-11 | 2014-04-02 | 刘海燕 | Recorder for recording running status of medical equipment and recording method thereof |
| CN102664125B (en) * | 2012-05-17 | 2014-04-30 | 许继集团有限公司 | Double high driving level-resistant magnetic latching relay driving circuit |
| CN103840717B (en) * | 2014-03-04 | 2017-12-29 | 李世雄 | Oil bath feeding machine controller |
| CN104459342A (en) * | 2014-12-26 | 2015-03-25 | 贵阳万江航空机电有限公司 | Parking position pulse width measuring instrument |
| CN105114335B (en) * | 2015-08-06 | 2017-05-17 | 中国石油天然气集团公司 | Anti-reverse device of electric submersible pump |
| CN106741986B (en) * | 2016-12-21 | 2023-08-29 | 太原航空仪表有限公司 | Rod vibrator with driving function |
| CN109004625B (en) * | 2017-08-11 | 2024-03-19 | 上海英奇电气科技有限公司 | Output loop interlocking system |
| CN108521241B (en) * | 2018-04-28 | 2021-01-15 | 常州电子研究所有限公司 | Switching mechanism drive circuit and drive method thereof |
| CN113419453A (en) * | 2021-06-29 | 2021-09-21 | 江苏天芯微半导体设备有限公司 | Interlocking circuit |
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| RU2011285C1 (en) * | 1991-01-09 | 1994-04-15 | Акционерное общество открытого типа "Челябинский металлургический комбинат" | Device for control of electric motor |
| CN2684459Y (en) * | 2004-02-17 | 2005-03-09 | 齐齐哈尔齐力达电子有限公司 | Non-contact phase change controller for three-phase motor |
| CN201008132Y (en) * | 2007-02-09 | 2008-01-16 | 吉林一夫环保节能科技有限公司 | Contactless commutation electricity-saving controller of asynchronous motor |
| CN201118492Y (en) * | 2007-11-05 | 2008-09-17 | 河南省新乡市矿山起重机有限公司 | A controller for control electromotor forward and reverser rotation based on relay |
| CN101453180A (en) * | 2007-12-05 | 2009-06-10 | 罗传兴 | Positive and negative rotating controller for motor |
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Effective date of registration: 20170602 Address after: Office building in Baiyun District of Guangzhou City, Guangdong province 510000 and the same road Meiyuan military cadres training center 1, 3 floor Patentee after: Guangzhou Sanchuan control system engineering equipment Co. Ltd. Address before: 510510 Guangdong city of Guangzhou province and the same road Meiyuan Plum Garden Villa No. 1 Patentee before: Zheng Guilin |
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