CN103607162B - The online switching device shifter of frequency conversion power frequency - Google Patents

The online switching device shifter of frequency conversion power frequency of the present invention, it comprises power module, processing module, EEPROM, output module, signal acquisition module, switching signal input circuit, display module, processing module comprises central processing unit and two-way RS485 telecommunication circuit, and two-way RS485 telecommunication circuit is electrically connected on central processing unit respectively; Signal acquisition module comprises 4 road signal acquisition circuits, and they are all connected on central processing unit; Described switching signal input circuit and EEPROM are electrically connected on central processing unit respectively; Described output module comprises the two-way relay output module be connected on central processing unit; Described display module comprises display circuit and display screen; Described power module provides 3 road 5V supplies of electric power for whole device.The present invention, by the signal of Real-time Collection frequency conversion, by the control of central processing unit and PLC, achieves low voltage starting and the soft handover of frequency converter work frequency conversion state.

The online switching device shifter of frequency conversion power frequency

Technical field

The present invention relates to a kind of switch, particularly relate to the online switching device shifter of a kind of frequency conversion power frequency.

Background technology

When motor is power frequency state from frequency conversion State Transferring, most employing directly switches, because during frequency conversion state, the output waveform phase place of frequency converter is not identical with the phase place between industrial-frequency alternating current, very large moment impact electric current can be caused, power supply grid, power supply unit, motor are all had a great impact, although also have switch controller on the market at present, these switch controllers only can realize state and switch, and can not realize the special tracking to a certain frequency converter and control.

Summary of the invention

For solving above-mentioned defect of the prior art, the invention provides the online switching device shifter of frequency conversion power frequency, solving in handoff procedure the problem producing impulse current, and the display that can realize frequency converter frequency conversion state and control.

For solving the problems of the technologies described above, the present invention program comprises: the online switching device shifter of frequency conversion power frequency, it is characterized in that, comprise power module, processing module, EEPROM, output module, signal acquisition module, switching signal input circuit, display module, described processing module comprises central processing unit and communication module, described communication module comprises two-way RS485 telecommunication circuit, and described two-way RS485 telecommunication circuit is electrically connected on central processing unit respectively; Described signal acquisition module comprises 4 road signal acquisition circuits, and 4 described road signal acquisition circuits are connected respectively on central processing unit; Described switching signal input circuit and EEPROM are electrically connected on central processing unit respectively; Described output module comprises two-way relay output module, and described two-way relay output module is electrically connected on central processing unit respectively; Described display module comprises display circuit and display screen, and described display circuit connects central processing unit and display screen respectively; Described power module provides 3 road 5V supplies of electric power for whole device.

Further, described display screen adopts the TFT LCD of 3.2 cun.

Further, described central processing unit adopts 32 ARM chip STM32F103.

Further, described power module comprises transformer T, current rectifying and wave filtering circuit, RCD circuit, feedback radiating circuit, feedback reception circuit, first voltage follower circuit, second voltage follower circuit and tertiary voltage output circuit, the input of described current rectifying and wave filtering circuit is connected in 220V AC power by choking-winding, the output of current rectifying and wave filtering circuit is connected with the input of RCD circuit, feedback reception circuit, first voltage follower circuit, second voltage follower circuit is connected respectively by the output of transformer with RCD circuit with tertiary voltage output circuit, the input of described feedback radiating circuit is connected with the first voltage follower circuit, the output of feedback radiating circuit is connected with feedback reception circuit, feedback reception circuit is connected with the output of current rectifying and wave filtering circuit by power-supply controller of electric.

Further, described signal acquisition circuit comprises resistance R16, resistance R17, resistance R18, resistance R19, resistance R20, resistance R21, resistance R22, resistance R23, resistance R24, electric capacity C18, electric capacity C19, electric capacity C20, electric capacity C21, electric capacity C22, electric capacity C23, electric capacity C24, triode Q1, diode D7, diode D8, diode D9, diode D10, diode D11, diode D12, optocoupler U2, Schmidt trigger CD4093, one end of R16 connects first input end, the other end of R16 connects the positive pole of D7, one end of R17 connects the second input, the other end of R17 connects the negative pole of D8, the positive pole of D9 connects D7 negative pole, the negative pole of D9 connects the negative pole of D10, the positive pole of D10 connects D11 positive pole and D12 positive pole respectively, the negative pole of D11 connects Q1 base stage, D12 negative pole connects Q1 emitter, the two ends of C18 connect D7 positive pole and D8 negative pole respectively, the two ends of C19 connect D7 negative pole and D8 positive pole respectively, C20 and C21 is in parallel with D10 respectively, one end of C22 connects Q1 base stage, the C22 other end connects D11 positive pole, C23 one end connects first pin of CD4093, C23 other end ground connection, and C24 and C23 is in parallel, first pin of U2 connects Q1 emitter, and the 3rd pin of U2 connects D6 positive pole, the 4th pin ground connection of U2, and the 6th pin of U2 connects 5V power supply by resistance R23, one end of R18 connects D7 negative pole, the R18 other end connects R19 one end and R20 one end respectively, the R19 other end connects D11 positive pole, the R20 other end connects Q1 base stage, R21 one end connects D9 negative pole, and the R21 other end connects Q1 collector electrode, and the two ends of R22 connect Q1 base stage and Q1 emitter respectively, one end of R24 connects the 6th pin of U2, and the R24 other end connects first pin of CD4093, first pin of CD4093 is connected with the second pin, and the 3rd pin of CD4093 connects output, and the 7th pin ground connection of CD4093, the 14 pin of CD4093 connects 5V power supply.

Further, described RS485 telecommunication circuit comprises RS485 communication chip ADM2483 and peripheral circuit, first pin of communication chip, 7th pin and the 16 pin are received on 5V power supply respectively, second pin of communication chip and the 8th pin digital grounding, 9th pin of communication chip and the 15 pin ground connection, 3rd pin of communication chip is connected with RX port, 6th pin of communication chip is connected with TX port, 12 pin of communication chip is connected on 5V power supply by resistance R25, 13 pin of communication chip is by resistance R28 ground connection, 4th pin of communication chip is connected with the 5th pin, described peripheral circuit comprises electric capacity C25, electric capacity C26, resistance R30, resistance R31, digit chip 74HC14, diode D13, diode D14, electric capacity C27, resistance R29, the positive pole of electric capacity C25 connects 5V power supply, the negative pole digital grounding of C25, the one termination 5V power supply of C26, the other end ground connection of C26, 14 pin of digit chip connects 3V power supply, 7th pin digital grounding of digit chip, first pin of digit chip connects RX port, 3rd pin and the 5th pin of digit chip connect TX port, second pin of digit chip is connected by the positive pole of resistance R31 and D16, 4th pin of digit chip is connected by the positive pole of resistance R30 and D15, the negative pole of D15 and the negative pole of D16 digital grounding respectively, 6th pin of digit chip connects the 4th pin of communication chip, the two ends of R26 connect the 12 pin and the first input end mouth of communication chip respectively, the two ends of R27 connect the 13 pin and second input port of communication chip respectively, one end of D13 connects first input end mouth, other end ground connection, one end of D14 connects the second input port, other end ground connection, one end of R29 connects ETH interface, other end ground connection, C27 and R29 also connects.

Further, described switching signal input circuit comprises resistance R32, resistance R33, resistance R34, resistance R35, resistance R36, electric capacity C28, electric capacity C29, electric capacity C30, electric capacity C31, electric capacity C32, diode D17, diode D18, diode D19, diode D20 and optocoupler U3, one end of R32 connects input 1, the R32 other end connects D17 positive pole, one end of R33 connects input 2, the R33 other end connects D18 positive pole, C28 two ends connect D17 negative pole and D18 negative pole respectively, C29 and C30 is in parallel with C28 respectively, and the positive pole of D19 connects D18 negative pole, and D19 negative pole connects D17 negative pole, the two ends of R34 connect D17 negative pole and D20 negative pole respectively, D20 positive pole connects D18 negative pole, and U3 first pin connects D20 negative pole, and U3 the 3rd pin connects D20 positive pole, U3 the 4th pin digital grounding, U3 the 6th pin connects 5V power supply by resistance R35, and R36 two ends connect U3 the 6th pin and output respectively, C31 mono-termination output, C31 other end digital grounding, C32 and C31 is in parallel.

The invention has the beneficial effects as follows: the present invention is by the signal of Real-time Collection frequency conversion; by the control of central processing unit and PLC; achieve low voltage starting and the soft handover of frequency converter work frequency conversion state; the problem of impulse current is produced when avoiding direct-cut operation; effectively protect power equipment; substantially prolongs the useful life of power equipment; and; the state of frequency conversion, operating process can also show on a display screen by the present invention in real time; intuitive and accurate control is defined to the whole process of equipment state and frequency conversion, improves efficiency greatly.

Accompanying drawing explanation

Fig. 1 is theory diagram of the present invention;

Fig. 2 is the circuit theory diagrams of power module of the present invention;

Fig. 3 is the present invention one road signal acquisition circuit schematic diagram;

Fig. 4 is the present invention one road RS485 telecommunication circuit schematic diagram;

Fig. 5 is switching signal input circuit schematic diagram of the present invention;

Annexation schematic diagram when Fig. 6 is using state of the present invention.

Embodiment

Below in conjunction with accompanying drawing, specific embodiment of the invention is described, should be appreciated that exemplifying embodiment described herein is only for instruction and explanation of the present invention, is not intended to limit the present invention.

The online switching device shifter of frequency conversion power frequency as shown in Figure 1, it comprises power module, processing module, EEPROM, output module, signal acquisition module, switching signal input circuit, display module, described processing module comprises central processing unit and communication module, described central processing unit adopts 32 ARM chip STM32F103, described communication module comprises two-way RS485 telecommunication circuit, and described two-way RS485 telecommunication circuit is electrically connected on central processing unit respectively; Described signal acquisition module comprises 4 road signal acquisition circuits, and 4 described road signal acquisition circuits are connected respectively on central processing unit; Described switching signal input circuit and EEPROM are electrically connected on central processing unit respectively; Described output module comprises two-way relay output module, and described two-way relay output module is electrically connected on central processing unit respectively; Described display module comprises display circuit and display screen, and described display circuit connects central processing unit and display screen respectively; Described power module provides 3 road 5V supplies of electric power for whole device.

As shown in Figure 2, described power module comprises transformer T, current rectifying and wave filtering circuit, RCD circuit, feedback radiating circuit, feedback reception circuit, first voltage follower circuit, second voltage follower circuit and tertiary voltage output circuit, the input of described current rectifying and wave filtering circuit is connected in 220V AC power by choking-winding, the output of current rectifying and wave filtering circuit is connected with the input of RCD circuit, feedback reception circuit, first voltage follower circuit, second voltage follower circuit is connected respectively by the output of transformer with RCD circuit with tertiary voltage output circuit, the input of described feedback radiating circuit is connected with the first voltage follower circuit, the output of feedback radiating circuit is connected with feedback reception circuit, feedback reception circuit is connected with the output of current rectifying and wave filtering circuit by power-supply controller of electric.

Described transformer T comprises the first winding, the second winding, the tertiary winding, the 4th winding and the 5th winding, the first described winding is input and is provided with input port 1 and input port 2, the second described winding is output and is provided with output port 3 and output port 4, the described tertiary winding is output and is provided with output port 5 and output port 6, the 4th described winding is output and is provided with output port 7 and output port 8, and the 5th described winding is output and is provided with output port 9 and output port 10.

Described current rectifying and wave filtering circuit comprises rectifier bridge BD1, electric capacity C1 and resistance R1, mainly play the effect of rectification and filtering, two inputs of BD1 are connected with two outputs of choking-winding L1X respectively, an input of L1X is connected with live wire by fuse FS1, another input of L1X is connected with zero line by thermistor RTH, described electric capacity C1 is connected with two outputs of rectifier bridge BD1 respectively, and the minus earth of electric capacity C1, resistance R1 is in parallel with electric capacity C1, wherein, choking-winding L1X can eliminate the common mode disturbances of feeder ear, fuse FS1 plays over-current and-load protective effect, thermistor RTH plays metering function.

Described RCD circuit comprises diode D1, diode D2, electric capacity C2, resistance R2 and resistance R3, is mainly used to absorb the momentary spikes voltage produced, thus protection transformer and control chip.The positive pole of D1 is connected with electric capacity C1 positive pole and transformer T input port 1 respectively, and the negative pole of D1 is connected with one end of R3, and the other end of R3 is connected with the negative pole of D2, and the positive pole of D2 is connected with the input port 2 of transformer T, and electric capacity C2 and resistance R2 is in parallel with D1 respectively.

It is fast recovery rectifier diode that the first described voltage follower circuit comprises diode D3, resistance R4, electric capacity C3, electric capacity C4, electric capacity C5, resistance R5, inductance L 1, electric capacity C6 and electric capacity C7, D3, plays rectified action; C3 plays a part to suppress concussion; protection rectifier diode, c4 is voltage stabilizing prime filter capacitor, absorbs voltage clutter; R5 is dummy load; power supply concussion when preventing rear class unloaded, C7 is output filter capacitor, eliminates voltage ripple and clutter; L1 is outputting inductance, strobes.The positive pole of D3 is connected with the output port 3 of transformer T, the negative pole of D3 is connected to one end of L1 by fuse FS2, the other end of L1 is connected to the first positive polarity delivery outlet, one end of R4 is connected with the positive pole of D3, the other end of R4 is connected with one end of C3, the other end of C3 is connected with the negative pole of D3, the positive pole of C4 is connected with the negative pole of D3, the negative pole of C4 is connected with the first voltage negative pole delivery outlet, one end of C5 is connected with the input port 1 of transformer T, the other end of C5 is connected with the negative pole of C4, R5 and C4 is in parallel, the positive pole of C6 is connected with the first positive polarity delivery outlet, the negative pole of C6 is connected with the first voltage negative pole delivery outlet, C7 and C6 is in parallel.

Described feedback radiating circuit comprises resistance R6, resistance R7, resistance R8, resistance R9, resistance R10, electric capacity C8, controllable accurate source of stable pressure TL431, optical coupler U1; be used for ensureing to ensure output voltage when load variations; wherein TL431 is a reference source; R7, R9, R10 form collection regulating networks; R6 is current-limiting resistance; R8 is protective resistance; the input of protection optocoupler U1; optocoupler U1 ensures the isolation of front stage circuit and the transmission of feedback signal; C8 is the filter capacitor of feedback circuit, prevents interference.One end of R6 is connected with the positive pole of C4, the other end of R6 is connected with the first input end of U1, the two ends of R8 are connected with U1 first input end and U1 second input respectively, one end of R7 is connected with the first positive polarity delivery outlet, the other end of R7 is connected with the B pole of TL431 and C8 one end respectively, the other end of C8 is connected with second input of U1, the K pole of TL431 is connected with second input of U1, the A pole of TL431 is connected with one end of R10, the other end of R10 is connected with one end of R9, the other end of R9 is connected with the B pole of TL431, the A pole of TL431 is also connected with the first voltage negative pole delivery outlet.

Described feedback reception circuit comprises diode D4, electric capacity C9, electric capacity C10, electric capacity C11, resistance R11, resistance R12, D4 are fast recovery rectifier diode, C9, C10, C11 is filter circuit, R11 is current-limiting resistance, suppress the charging current of electric capacity C10, the positive pole of D4 is connected with the output port 9 of transformer T, the negative pole of D4 is connected with the positive pole of C9, the minus earth of C9, one end of R11 is connected with the C port of power-supply controller of electric TOP244, the other end of R11 is connected with the positive pole of C10, the minus earth of C10, one end of C11 is connected with the C port of power-supply controller of electric TOP244, the other end ground connection of C11, one end of R12 is connected with the X port of power-supply controller of electric TOP244, the other end ground connection of R12, the output port 10 of transformer T, the F port of power-supply controller of electric TOP244, the S port ground connection respectively of power-supply controller of electric TOP244, the D port of power-supply controller of electric TOP244 is connected on the input port 2 of transformer T, the L port of power-supply controller of electric TOP244 is connected with the positive pole of electric capacity C1 by resistance R13, two outputs of U1 are connected with the negative pole of D4 and the C port of power-supply controller of electric TOP244 respectively, wherein, TOP244 produces pwm signal, R13 is existing voltage acquisition current-limiting resistance.

The second described voltage follower circuit comprises diode D5, resistance R14, electric capacity C12, electric capacity C13, electric capacity C14, circuit of three-terminal voltage-stabilizing integrated U2, U2 ensures output voltage stabilization, D5 is fast recovery rectifier diode, play rectified action, C13, C14 are output filter capacitor, eliminate voltage ripple and clutter, C12 is voltage stabilizing prime filter capacitor, absorb voltage clutter, R14 is dummy load, the effect of power supply concussion when preventing rear class unloaded.The positive pole of D5 is connected with the output port 5 of transformer T, the negative pole of D5 is connected with the positive pole of C12, the negative pole of C12 is connected with the output port 6 of transformer T, R14 and C12 is in parallel, the input pin of U2 is connected with the negative pole of D5, the output pin of U2 is connected with the second positive polarity delivery outlet by fuse FS3, the grounding pin of U2 is connected with the second voltage negative pole delivery outlet, the positive pole of C13 is connected with the second positive polarity delivery outlet, the negative pole of C13 is connected with the second voltage negative pole delivery outlet, C14 and C13 is in parallel, and the negative pole of C12 is also connected with the negative pole of C13.

Described tertiary voltage output circuit comprises diode D6, resistance R15, electric capacity C15, electric capacity C16, electric capacity C17, circuit of three-terminal voltage-stabilizing integrated U3, U3 ensures output voltage stabilization, D6 is fast recovery rectifier diode, play rectified action, C16, C17 are output filter capacitor, eliminate voltage ripple and clutter, C15 is voltage stabilizing prime filter capacitor, absorb voltage clutter, R15 is dummy load, the effect of power supply concussion when preventing rear class unloaded.The positive pole of D6 is connected with the output port 7 of transformer T, the negative pole of D6 is connected with the positive pole of C15, the negative pole of C15 is connected with the output port 8 of transformer T, R15 and C15 is in parallel, the input pin of U3 is connected with the negative pole of D6, the output pin of U3 is connected with tertiary voltage positive pole delivery outlet by fuse FS4, the grounding pin of U3 is connected with tertiary voltage negative pole delivery outlet, the positive pole of C16 is connected with tertiary voltage positive pole delivery outlet, the negative pole of C16 is connected with tertiary voltage negative pole delivery outlet, C17 and C16 is in parallel, and the negative pole of C15 is also connected with the negative pole of C17.

Preferably, FS2, FS3, FS4 are resettable fuse, prevent output overloading or short circuit, described circuit of three-terminal voltage-stabilizing integrated U2 and circuit of three-terminal voltage-stabilizing integrated U3 all adopt model be 7805 circuit of three-terminal voltage-stabilizing integrated, described electric capacity C1, electric capacity C4, electric capacity C6, electric capacity C9, electric capacity C10, electric capacity C12, electric capacity C13, electric capacity C15, electric capacity C16 are polar capacitor, and described resistance R10 is variable resistance.

When after the access of 220V alternating current, after a series of process such as over commutation, filtering, step-down, voltage stabilizing, Energy control, the direct voltage of 5V, 2A is exported from the first voltage output end, export the direct voltage of 5V, 0.2A from the second voltage output end, export the direct voltage of 5V, 0.2A from tertiary voltage output.

Signal acquisition module comprises the identical signal acquisition circuit in 4 tunnels, as shown in Figure 3, described signal acquisition circuit comprises resistance R16, resistance R17, resistance R18, resistance R19, resistance R20, resistance R21, resistance R22, resistance R23, resistance R24, electric capacity C18, electric capacity C19, electric capacity C20, electric capacity C21, electric capacity C22, electric capacity C23, electric capacity C24, triode Q1, diode D7, diode D8, diode D9, diode D10, diode D11, diode D12, optocoupler U2 and Schmidt trigger CD4093

One end of R16 connects first input end, the other end of R16 connects the positive pole of D7, one end of R17 connects the second input, the other end of R17 connects the negative pole of D8, the positive pole of D9 connects D7 negative pole, and the negative pole of D9 connects the negative pole of D10, and the positive pole of D10 connects D11 positive pole and D12 positive pole respectively, the negative pole of D11 connects Q1 base stage, and D12 negative pole connects Q1 emitter;

The two ends of C18 connect D7 positive pole and D8 negative pole respectively, the two ends of C19 connect D7 negative pole and D8 positive pole respectively, C20 and C21 is in parallel with D10 respectively, one end of C22 connects Q1 base stage, the C22 other end connects D11 positive pole, C23 one end connects first pin of CD4093, C23 other end ground connection, and C24 and C23 is in parallel;

First pin of U2 connects Q1 emitter, and the 3rd pin of U2 connects D6 positive pole, the 4th pin ground connection of U2, and the 6th pin of U2 connects 5V power supply by resistance R23;

One end of R18 connects D7 negative pole, the R18 other end connects R19 one end and R20 one end respectively, the R19 other end connects D11 positive pole, the R20 other end connects Q1 base stage, R21 one end connects D9 negative pole, and the R21 other end connects Q1 collector electrode, and the two ends of R22 connect Q1 base stage and Q1 emitter respectively, one end of R24 connects the 6th pin of U2, and the R24 other end connects first pin of CD4093;

First pin of CD4093 is connected with the second pin, and the 3rd pin of CD4093 connects output, and the 7th pin ground connection of CD4093, the 14 pin of CD4093 connects 5V power supply.

In foregoing circuit, described 5V power supply is by a capacity earth, and this electric capacity is used for decoupling and shaping, the impact of the wild effect of power supply on circuit can be weakened, the model of described U2 is TLP185, and described D10 and D11 is voltage stabilizing didoe, and described Q1 is NPN type triode.

Complete signal acquisition circuit by four independently foregoing circuit form, this circuit first input end and the second input are connected input and the output of converter power supply respectively, the Transistor-Transistor Logic level signal of standard is changed into CPU element, in this circuit by foregoing circuit:

R16, R17 form step-down Acquisition Circuit, realize the step-down process to 380V input signal.

C18 realizes the absorption to the waveform spike gathering power supply.

D7, D8 are rectifier diode, and the AC signal of input is changed direct current signal.

C22 is filter capacitor, stablizes input signal.

R18, R19 form signal attenuation circuit, and ensure that input signal is decayed in proportion, attenuated signal, by current-limiting resistance R20 and filter capacitor C22, is sent to the ground level of triode Q1, carries out scale amplifying, controls the operating state of optocoupler U2.

R22 is protective resistance, prevents the impact of abnormal input to triode Q1.

D11 is 3V voltage-stabiliser tube, ensures the input signal of triode Q1, is no more than 3V thus protection triode.

D12 protects the input of optocoupler U1, ensures that the pressure drop of optocoupler keeps and 0.7V.

D9, D10, C20, C21 are current rectifying and wave filtering circuit, and the work for optocoupler U2 provides sufficient power supply, and wherein, D10 is 5.1V voltage-stabiliser tube, ensure that this supply voltage is stablized and 5.1V; C19, C20 are filter circuit.

Resistance R21 is current-limiting resistance, and electric current when ensureing optocoupler U2 work maintains zone of reasonableness.

Resistance R23 is pull-up resistor, provides sufficient driving force for rear class exports.

R24, C23, C24 form RC filter network, eliminate the abnormal spike of input, make input signal more stable.

Schmidt trigger CD4093 plays shaping operation, ensures that signal exports the Transistor-Transistor Logic level for standard.

Described communication module comprises the identical RS485 telecommunication circuit of two-way, the one embedded frequency conversion communication protocol in tunnel, the operational factor of frequency converter is gathered by communication mode, the embedded Modbus agreement in another road, be connected with host computer, the operating state of the frequency conversion state gathered and switch is uploaded to host computer, as shown in Figure 4, described RS485 telecommunication circuit comprises RS485 communication chip ADM2483 and peripheral circuit, first pin of communication chip, 7th pin and the 16 pin are received on 5V power supply respectively, second pin of communication chip and the 8th pin digital grounding, 9th pin of communication chip and the 15 pin ground connection, 3rd pin of communication chip is connected with RX port, 6th pin of communication chip is connected with TX port, 12 pin of communication chip is connected on 5V power supply by resistance R25, 13 pin of communication chip is by resistance R28 ground connection, 4th pin of communication chip is connected with the 5th pin, described peripheral circuit comprises electric capacity C25, electric capacity C26, resistance R30, resistance R31, digit chip 74HC14, diode D13, diode D14, electric capacity C27, resistance R29, the positive pole of electric capacity C25 connects 5V power supply, the negative pole digital grounding of C25, the one termination 5V power supply of C26, the other end ground connection of C26, 14 pin of digit chip connects 3V power supply, 7th pin digital grounding of digit chip, first pin of digit chip connects RX port, 3rd pin and the 5th pin of digit chip connect TX port, second pin of digit chip is connected by the positive pole of resistance R31 and D16, 4th pin of digit chip is connected by the positive pole of resistance R30 and D15, the negative pole of D15 and the negative pole of D16 digital grounding respectively, 6th pin of digit chip connects the 4th pin of communication chip, the two ends of R26 connect the 12 pin and the first input end mouth of communication chip respectively, the two ends of R27 connect the 13 pin and second input port of communication chip respectively, one end of D13 connects first input end mouth, other end ground connection, one end of D14 connects the second input port, other end ground connection, one end of R29 connects ETH interface, other end ground connection, C27 and R29 also connects.

Wherein, RS485 communication chip ADM2483 is a integrated form electric current isolating device, be applicable to the bidirectional data communication of multi-point bus transmission line, it designs for balanced transmission line, meet ANSITIA/EIARS-485-A and ISO8482:1987 (E) standard, this device adopts the iCoupler technology of ADI company, by 3 member passage way isolating apparatus, tri-state differential line driver and Differential Input receiver are integrated in single encapsulation, play communication isolating and level conversion effect in circuit, and, this chip adopts two-way independently Power supply, realize for electric isolution.

Electric capacity C25, C26 for moving back lotus root electric capacity, in order to eliminate the unusual waveforms of power supply and to absorb chip operation and the pulse that produces.

Not gate digit chip 74HC14 realization is to the transmission of ADUM2483 and accept control; because the delay of 74HC14 is very little; guarantee realizes zero propagation and sends and accept; simultaneously; 74HC14, R30, R31, D15, D16 realize instruction bus data being sent to receive status jointly; be convenient to observe and understand data interaction state; concrete function is: 74HC14 realizes amplifying and drives function; R30, R31 are current-limiting resistance; limiting circuit current protection diode; D15, D16 are light-emitting diode, realize the instruction to operating state.

R25, R28 are bus biasing resistor, enhance bus driver ability, ensure that transmittability and the antijamming capability of signal.

R26, R27 are current limiting safeguard resistor, can when abnormal signal, limiting input current, thus protection late-class circuit.

D13, D14 are transient voltage suppressor; select P6KE15CA; the advantages such as this diode possesses fast response time, transient absorption power is large, leakage current is little (microampere order), conducting voltage precision is high, clamping voltage is more easy to control, volume is little; can effectively suppress common mode, differential mode interference, protection late-class circuit exempts from the various Electromagnetic Interference such as electrostatic, thunder and lightning, switching overvoltage.

R29, C27 form RC network, realize due to voltage spikes can leak in time cause the earth, thus play protection bus effect.

Wherein, described first input end mouth and the second input port be host computer communication port or frequency converter communicate gather port, described D15 and D16 is light-emitting diode, described C25 is for there being polar capacitor, described D13 and D14 is voltage stabilizing didoe, described C25, communication chip the 7th pin and communication chip first pin access source nominal electric current be 2A, described C26, R25 and communication chip the 16 pin access source nominal electric current be 0.2A.

As shown in Figure 5, described switching signal input circuit comprises resistance R32, resistance R33, resistance R34, resistance R35, resistance R36, electric capacity C28, electric capacity C29, electric capacity C30, electric capacity C31, electric capacity C32, diode D17, diode D18, diode D19, diode D20 and optocoupler U3, one end of R32 connects input 1, the R32 other end connects D17 positive pole, one end of R33 connects input 2, the R33 other end connects D18 positive pole, C28 two ends connect D17 negative pole and D18 negative pole respectively, C29 and C30 is in parallel with C28 respectively, and the positive pole of D19 connects D18 negative pole, and D19 negative pole connects D17 negative pole, the two ends of R34 connect D17 negative pole and D20 negative pole respectively, D20 positive pole connects D18 negative pole, and U3 first pin connects D20 negative pole, and U3 the 3rd pin connects D20 positive pole, U3 the 4th pin digital grounding, U3 the 6th pin connects 5V power supply by resistance R35, and R36 two ends connect U3 the 6th pin and output respectively, C31 mono-termination output, C31 other end digital grounding, C32 and C31 is in parallel.

The high-voltage signal that this main circuit will realize inputting is converted to the acceptable low voltage signal of CPU, and wherein, R32, R33 form dropping resistor network, reduce the voltage magnitude of input signal; D17, D18 are rectifier diode, are direct current signal by the AC signal rectification of input; C28 is pulse absorb electric capacity, absorbs impulse wave; D19 is voltage stabilizing didoe; C29, C30 are filter circuit, play the effect of filtering; The photoisolator of U3 to be model be TLP185, plays buffer action; D20 is used for protecting the input of photoelectrical coupler; R35 is pull-up resistor, strengthens the driving force of output signal; R36, C31, C32 are the unusual part of RC filter network, filtered signal.

As shown in Figure 6, QF1, QF2 are circuit breaker, and KM1, KM2, KM3 are contactor, and KH1 is thermal relay, once motor overload, overcurrent shield.After the instruction that the online switching device shifter of frequency conversion power frequency accepts remote controllers or PLC, host computer sends, gather the input/output signal of frequency converter and real-time tracking by terminal 1, terminal 2, terminal 3, terminal 4, terminal 5, terminal 6.

If follow the tracks of successfully, terminal 14,15 is closed sends signal, after remote controllers or PLC, host computer accept this signal, disconnects KM1, KM2 adhesive simultaneously KM3, switches to power frequency loop, realize switching.

If follow the tracks of unsuccessfully, terminal 8,9,10 sends signal to remote controllers or PLC, host computer, and the online switching device shifter of frequency conversion power frequency gathers the operational factor of frequency conversion by communication terminal 17,18, and is forwarded by terminal 19,20 realization isolation.

Should be understood that; the above-mentioned description for preferred embodiment is comparatively detailed; therefore the restriction to scope of patent protection of the present invention can not be thought; those of ordinary skill in the art is under enlightenment of the present invention; do not departing under the ambit that the claims in the present invention protect; can also make the various deformation such as replacement, simple combination, these all fall within protection scope of the present invention, and request protection range of the present invention should be as the criterion with claims.