CN109150061A

CN109150061A - A kind of heavy-duty motor work frequency conversion switching system and its control method

Info

Publication number: CN109150061A
Application number: CN201811100426.9A
Authority: CN
Inventors: 张庆平
Original assignee: Shandong Aozhuo Electrical Science And Technology Development Co Ltd
Current assignee: Shandong Aozhuo Electrical Science And Technology Development Co Ltd
Priority date: 2018-09-20
Filing date: 2018-09-20
Publication date: 2019-01-04
Anticipated expiration: 2038-09-20
Also published as: CN109150061B

Abstract

Present invention mainly discloses a kind of heavy-duty motor work frequency conversion switching system and its control methods, it includes Acquisition Circuit unit, decision circuitry unit, control circuit unit, execution circuit unit, electric control loop unit；The Acquisition Circuit unit is connect with decision circuitry unit, and the decision circuitry unit is connect with control circuit unit and execution circuit unit；The execution circuit unit is connect with electric control loop unit；The electric control loop unit is connected to motor；The Acquisition Circuit unit includes acquisition signaling module, rectification module, power supply signal processing module, comparison signal processing module；The decision circuitry unit includes amplification circuit module and phase detecting circuit module；The invention patent effectively improves the success rate of switching, can fast and accurately capture Phase synchronization, and system is simple and efficient, and the stability that system simply switches afterwards just will increase with success rate, and system effectively reduces cost, can be mass processing.

Description

A kind of heavy-duty motor work frequency conversion switching system and its control method

Technical field

The present invention relates to frequency converter fields, and in particular to a kind of heavy-duty motor work frequency conversion switching system and its controlling party Method.

Background technique

To save cost, as soon as production scene generally only selects a frequency converter and two motors to use simultaneously, this need into Conversion of the row power frequency to frequency conversion；Low power motor is small because loading, and not high to the phase requirements of power grid, work frequency conversion can successfully be cut It changes；But for heavy-duty motor, because it is first detached from operation of power networks at work, motor load is big, and motor has excitation punching It hits, with the growth of motor operating time, motor speed landing is too big, and slippage impact starts to significantly rise；And frequency converter exports The start-phase of voltage is random, uncertain, even if the output voltage frequency of frequency converter is equal to power-frequency voltage frequency, institute is defeated The initial phase of three phase mains and power frequency supply out is also inconsistent, inconsistent due to phase, causes in handoff procedure In various problems, the problem of making heavy-duty motor VF to WF, is more complicated, exports and originates just because of frequency converter voltage Phase has randomness, and the three phase mains of frequency converter output and the initial phase of power frequency supply are inconsistent, results in motor switching When the transient current that generates also there is randomness, be much larger than the rated current of motor sometimes, show as electricity in production at the scene The current or voltage of machine overloads, and air switch is made to trip, and burns fuse, motor device can be also damaged when serious.

Summary of the invention

To solve the problems, such as that above-mentioned heavy-duty motor exists in work frequency conversion switching, the present invention provides a kind of high-power electricity Machine work frequency conversion switching system and its control method.

A kind of heavy-duty motor work frequency conversion switching system, comprising:

Acquisition Circuit unit, for acquiring voltage of the two-phase electricity of power grid with frequency converter with the mutually two-phase electricity of output；

Decision circuitry unit, for the voltage of acquisition and phase signal to be compared processing；

Control circuit unit carries out sweeping action for controlling Acquisition Circuit unit and decision circuitry unit, until reaching corresponding Control requirement；

Execution circuit unit is mainly used to execute the ON operation of electric control loop unit；

Electric control loop unit, control motor completes the locking phase of output waveform, while it is complete to control major loop switch circuit units At the conversion work of work frequency conversion；

The Acquisition Circuit unit is connect with decision circuitry unit, the decision circuitry unit and control circuit unit and is held The connection of row circuit unit；The execution circuit unit is connect with electric control loop unit；The electric control loop list Member is connected to motor.

The Acquisition Circuit unit includes acquisition signaling module, rectification module, power supply signal processing module, comparison signal Processing module；The acquisition signaling module is connect with rectification module, and the rectification module is divided into rectifier bridge one and rectifier bridge Two；The rectifier bridge one is connect with power supply signal processing module, and the rectifier bridge two is connect with comparison signal processing module； The acquisition signaling module is connect with transformer T1, transformer T2 respectively；Transformer T1 is connect with rectifier bridge one, rectifier bridge one It connect, is handled as power supply signal with power supply signal processing module；Transformer T2 is connect with rectifier bridge two, the letter compared with of rectifier bridge two The connection of number processing module, is handled as comparison signal；The power supply signal processing module is connect with circuit board, is provided for circuit board Power supply；The comparison signal processing module is lm324 comparator.

The decision circuitry unit includes amplification circuit module and phase detecting circuit module；The amplifying circuit mould Block is connect with phase detecting circuit module；Decision circuitry unit passes through the conducting of output pin control switch one and switch two, into And ON-OFF control circuit unit acts, and the operating point of switch one and switch two is adjusted by potentiometer R6；When phase-detection electricity It after road module detects that phase is consistent, is turned off by the actuation that switch three controls relay K1, completes the detection control of phase；When When phase detecting circuit module detects that phase is inconsistent, control circuit unit controls Acquisition Circuit unit and decision circuitry unit Acquisition and judgement are re-executed, until detecting that phase is consistent.

The electric control loop unit includes frequency converter extension relay, phase-detection relay, A.C. contactor KM1, time relay KT, intermediate relay KA, A.C. contactor KM2, start button SB1；The frequency converter extends relay Device, phase-detection relay are connected in series；After the phase-detection relay concatenate A.C. contactor KM2 normally-closed contact one, Intermediate relay KA normally opened contact；The start button SB1 and start button SB2, it intermediate relay KA normally-closed contact, exchanges Contactor KM2 normally-closed contact two, A.C. contactor KM1 normally opened contact are connected in series；The time relay KT normally opened contact It is concatenated with start button SB3, A.C. contactor KM1 normally-closed contact, A.C. contactor KM2 normally opened contact.

A kind of heavy-duty motor work frequency conversion method for handover control, comprising:

A, the two-phase electricity of acquisition circuit module acquisition power grid is with frequency converter with the voltage of the mutually two-phase electricity of output, and a part is through transformation Device TI is converted to the voltage in controlled range, after rectifying via the rectifier bridge one that D1, D2, D3, D4 rectifier compose in parallel, then passes through The processing of power supply signal processing module is power supply signal；A part is converted to the voltage in controlled range through transformer T2, via D5, After the rectifier bridge two that D6, D7, D8 rectifier compose in parallel rectifies, then handling through comparison signal processing module is comparison signal；

B, decision circuitry unit compares the comparison signal of acquisition after operational amplifier U1 amplification with the parameter of default Compared with when comparison signal is consistent with setup parameter, decision circuitry unit will judge that signal is transmitted to execution circuit unit；When comparing letter Number with setup parameter it is inconsistent when, decision circuitry unit will judge that signal is transmitted to control circuit unit；Control circuit unit is again It controls Acquisition Circuit unit and executes collection voltages signalizing activity, until the voltage signal of acquisition compares one through decision circuitry unit It causes, control circuit unit stopping movement；

C, execution circuit unit control electric control loop unit conducting, completes the conversion of work frequency conversion；The control of execution circuit unit Change-over switch SA closure, while frequency converter is started by control start button SB1, the contact of A.C. contactor KM1 normally opened contact is inhaled With the operation of, frequency converter, for the precise and high efficiency for guaranteeing phase-detection, target frequency is higher than alternating current, and frequency converter is run to mesh After marking frequency 50.10hz, frequency converter extends PA, PC contact closure of relay, and phase detecting circuit unit detects phase one After cause, PA, PC contact closure of phase-detection relay, while intermediate relay KA normally opened contact is attracted, A.C. contactor KM1 Normally opened contact disconnects, and control time relay KT obtains electric, the time relay KT normally opened contact closure after being delayed after a period of time, A.C. contactor KM2 normally opened contact obtains electric actuation, completes the conversion of converting operation to power frequency;

D, electric control loop unit control motor completes the locking phase of output waveform, while controlling switch circuit units and completing motor By the switching of power frequency to frequency conversion；A.C. contactor KM1 is converting operation major loop contactor, and A.C. contactor KM2 is power frequency fortune Row major loop contactor, two contactors cannot be closed at, it is ensured that A.C. contactor KM1 disconnects exchange after a certain period of time and connects Tentaculum KM2 could be attracted.

The invention patent effectively improves the success rate of switching, can fast and accurately capture Phase synchronization.Become when checking It is switched at once after the Phase synchronization of frequency device and power grid, this can effectively prevent switching in the case where uncertain phase to bring Rush of current, prevent damage power switch and contactor arcing etc., and system is simple and efficient, and system simply switches steady afterwards It is qualitative just to will increase with success rate.System effectively reduces cost, can be mass processing.

Detailed description of the invention

Fig. 1: the invention patent structural block diagram；

Fig. 2: the invention patent acquires signal element structural block diagram；

Fig. 3: the invention patent decision circuitry cellular construction block diagram；

Fig. 4: the invention patent electric control loop element circuit figure.

Fig. 5: the invention patent major loop switch circuit units circuit diagram.

Specific embodiment

Acquisition Circuit unit (1), for acquiring voltage of the two-phase electricity of power grid with frequency converter with the mutually two-phase electricity of output；

Decision circuitry unit (2), for the voltage of acquisition and phase signal to be compared processing；

Control circuit unit (3) carries out sweeping action for controlling Acquisition Circuit unit (1) and decision circuitry unit (2), until Reach corresponding control to require；

Execution circuit unit (4) is mainly used to execute the ON operation of electric control loop unit (5)；

The locking phase of output waveform is completed in electric control loop unit (5), control motor (6), while controlling major loop switching circuit The conversion work of unit completion work frequency conversion；

The Acquisition Circuit unit (1) is connect with decision circuitry unit (2), the decision circuitry unit (2) and control electricity Road unit (3) and execution circuit unit (4) connection；The execution circuit unit (4) and electric control loop unit (5) is even It connects；The electric control loop unit (5) is connect with motor (6).

The Acquisition Circuit unit (1) includes acquisition signaling module (101), rectification module (102), power supply signal processing Module (103), comparison signal processing module (104)；The acquisition signaling module (101) is connect with rectification module (102), institute The rectification module (102) stated is divided into rectifier bridge one (105) and rectifier bridge two (106)；The rectifier bridge one (105) and power supply is believed The connection of number processing module (103), the rectifier bridge two (106) are connect with comparison signal processing module (104)；The acquisition Signaling module (101) is connect with transformer T1(107), transformer T2(108) respectively；Transformer T1(107) and rectifier bridge one (105) it connects, rectifier bridge one (105) connect with power supply signal processing module (103), handles as power supply signal；Transformer T2 (108) it is connect with rectifier bridge two (106), rectifier bridge two (106) is connect with comparison signal processing module (104), is handled to compare Signal；The power supply signal processing module (103) is connect with circuit board (109), provides power supply for circuit board (109)；It is described Comparison signal processing module (104) be lm324 comparator.

The decision circuitry unit (2) includes amplification circuit module (201) and phase detecting circuit module (202)；Institute The amplification circuit module (201) stated is connect with phase detecting circuit module (202)；Decision circuitry unit (2) passes through output pin The conducting of control switch one (203) and switch two (204), and then ON-OFF control circuit unit (3) acts, and passes through potentiometer R6 (205) R6 adjusts the operating point of switch one (203) and switch two (204)；When phase detecting circuit module (202) detects phase After consistent, pass through switch three (206) and control relay K1(207) actuation shutdown, the detection for completing phase controls；When phase is examined When slowdown monitoring circuit module (202) detects that phase is inconsistent, control circuit unit (3) controls Acquisition Circuit unit (1) and judgement electricity Road unit (2) re-executes acquisition and judgement, until detecting that phase is consistent.

The electric control loop unit (5) includes frequency converter extension relay (501), phase-detection relay (502), A.C. contactor KM1(503), time relay KT(504), intermediate relay KA(505), A.C. contactor KM2 (506), start button SB1(507)；The frequency converter extends relay (501), phase-detection relay (502) series connection connects It connects；It is normal that the phase-detection relay (502) concatenates A.C. contactor KM2 normally-closed contact one (509), intermediate relay KA afterwards Open contact (510)；The start button SB1(507) with start button SB2(508), intermediate relay KA normally-closed contact (511), A.C. contactor KM2 normally-closed contact two (512), A.C. contactor KM1 normally opened contact (513) are connected in series；Described Time relay KT normally opened contact (514) and start button SB3(515), A.C. contactor KM1 normally-closed contact (516) are exchanged and are connect Tentaculum KM2 normally opened contact (517) concatenation.

A, the two-phase electricity of acquisition signaling module (101) acquisition power grid is with frequency converter with the voltage of the mutually two-phase electricity of output, a part The voltage in controlled range is converted to through transformer TI, the rectifier bridge one (105) composed in parallel via D1, D2, D3, D4 rectifier After rectification, then handling through power supply signal processing module (103) is power supply signal；A part is converted to through transformer T2(108) can The voltage in range is controlled, after rectifier bridge two (106) rectification composed in parallel via D5, D6, D7, D8 rectifier, then through comparing letter The processing of number processing module (104) is comparison signal；

B, decision circuitry unit (2) carries out the comparison signal of acquisition after operational amplifier U1 amplification with the parameter of default Compare, when comparison signal is consistent with setup parameter, decision circuitry unit (2) will judge that signal is transmitted to execution circuit unit (4)； When comparison signal and setup parameter are inconsistent, decision circuitry unit (2) will judge that signal is transmitted to control circuit unit (3)；Control Circuit unit (3) processed controls Acquisition Circuit unit (1) again and executes collection voltages signalizing activity, until the voltage signal warp of acquisition Decision circuitry unit (2) is than more consistent, control circuit unit (3) stopping movement；

C, the conversion of work frequency conversion is completed in execution circuit unit (4) control electric control loop unit (5) conducting；Execution circuit list First (4) control change-over switch SA(7) closure, while passing through control start button SB1(507) and starting frequency converter, A.C. contactor KM1 normally opened contact (513) contacts suction and frequency converter operation, for the precise and high efficiency for guaranteeing phase-detection, target frequency is than alternating current It is high, frequency converter is run to target frequency 50.10hz, frequency converter extends PA, PC contact closure of relay (501), phase After position detection circuit unit detects that phase is consistent, PA, PC contact closure of phase-detection relay (502), while it is intermediate after Electric appliance KA normally opened contact (510) is attracted, and A.C. contactor KM1 normally opened contact (513) disconnects, and controls time relay KT(504) Obtain electric, time relay KT normally opened contact (514) closure, A.C. contactor KM2 normally opened contact after being delayed after a period of time (517) electric actuation is obtained, the conversion of converting operation to power frequency is completed;

D, the locking phase of output waveform is completed in electric control loop unit (5) control motor (6), while it is complete to control switch circuit units At motor (6) by the switching of power frequency to frequency conversion；A.C. contactor KM1(503) it is converting operation major loop contactor, ac contactor Device KM2(506) it is power frequency operation major loop contactor, two contactors are realized interlocking, cannot be closed at, it is ensured that exchange connects Tentaculum KM1(503) disconnect A.C. contactor KM2(506 after a certain period of time) could be attracted.

Claims

1. a kind of heavy-duty motor work frequency conversion switching system, it is characterized in that: including:

2. a kind of heavy-duty motor work frequency conversion switching system according to claim 1, it is characterised in that: the acquisition electricity Road unit (1) include acquisition signaling module (101), rectification module (102), power supply signal processing module (103), at comparison signal It manages module (104)；The acquisition signaling module (101) is connect with rectification module (102), the rectification module (102) point For rectifier bridge one (105) and rectifier bridge two (106)；The rectifier bridge one (105) and power supply signal processing module (103) is even It connects, the rectifier bridge two (106) is connect with comparison signal processing module (104)；The acquisition signaling module (101) is respectively It is connect with transformer T1(107), transformer T2(108)；Transformer T1(107) it is connect with rectifier bridge one (105), rectifier bridge one (105) it connect, is handled as power supply signal with power supply signal processing module (103)；Transformer T2(108) and rectifier bridge two (106) Connection, rectifier bridge two (106) connect with comparison signal processing module (104), handle as comparison signal；At the power supply signal Reason module (103) is connect with circuit board (109), provides power supply for circuit board (109)；The comparison signal processing module It (104) is lm324 comparator.

3. a kind of heavy-duty motor work frequency conversion switching system according to claim 1, it is characterised in that: the judgement electricity Road unit (2) includes amplification circuit module (201) and phase detecting circuit module (202)；The amplification circuit module (201) It is connect with phase detecting circuit module (202)；Decision circuitry unit (2) passes through output pin control switch one (203) and switch The conducting of two (204), and then ON-OFF control circuit unit (3) acts, and passes through potentiometer R6(205) R6 adjustment switch one (203) and the operating point of switch two (204)；After phase detecting circuit module (202) detects that phase is consistent, pass through switch three (206) control relay K1(207) actuation shutdown, complete phase detection control；When phase detecting circuit module (202) are examined Measure phase it is inconsistent when, control circuit unit (3) control Acquisition Circuit unit (1) and decision circuitry unit (2) re-execute Acquisition and judgement, until detecting that phase is consistent.

4. a kind of heavy-duty motor work frequency conversion switching system according to claim 1, it is characterised in that: the electric-controlled Circuit units (5) processed include frequency converter extension relay (501), phase-detection relay (502), A.C. contactor KM1 (503), time relay KT(504), intermediate relay KA(505), A.C. contactor KM2(506), start button SB1 (507)；The frequency converter extends relay (501), phase-detection relay (502) is connected in series；The phase-detection Relay (502) concatenates A.C. contactor KM2 normally-closed contact one (509), intermediate relay KA normally opened contact (510) afterwards；It is described Start button SB1(507) with start button SB2(508), intermediate relay KA normally-closed contact (511), A.C. contactor KM2 Normally-closed contact two (512), A.C. contactor KM1 normally opened contact (513) are connected in series；The time relay KT normally opened contact (514) with start button SB3(515), A.C. contactor KM1 normally-closed contact (516), A.C. contactor KM2 normally opened contact (517) Concatenation.

5. a kind of heavy-duty motor work frequency conversion switching system control method described in -4 any claims according to claim 1, It is characterized by comprising:

C, the conversion of work frequency conversion is completed in execution circuit unit (4) control electric control loop unit (5) conducting；Execution circuit list First (4) control change-over switch SA(7) closure, while passing through control start button SB1(507) and starting frequency converter, A.C. contactor KM1 normally opened contact (513) contacts suction and frequency converter operation, for the precise and high efficiency for guaranteeing phase-detection, target frequency is than alternating current It is high, frequency converter is run to target frequency 50.10hz, frequency converter extends PA, PC contact closure of relay (501), phase After position detection circuit unit detects that phase is consistent, PA, PC contact closure of phase-detection relay (502), while it is intermediate after Electric appliance KA normally opened contact (510) is attracted, and A.C. contactor KM1 normally opened contact (513) disconnects, and controls time relay KT(504) Obtain electric, time relay KT normally opened contact (514) closure, A.C. contactor KM2 normally opened contact after being delayed after a period of time (517) electric actuation is obtained, the conversion of converting operation to power frequency is completed；