CN201422099Y - Inverter-overturning resistant seamless interchange motor speed regulating control system - Google Patents
Inverter-overturning resistant seamless interchange motor speed regulating control system Download PDFInfo
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- CN201422099Y CN201422099Y CN2009201519015U CN200920151901U CN201422099Y CN 201422099 Y CN201422099 Y CN 201422099Y CN 2009201519015 U CN2009201519015 U CN 2009201519015U CN 200920151901 U CN200920151901 U CN 200920151901U CN 201422099 Y CN201422099 Y CN 201422099Y
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Abstract
The utility model discloses an inverter-overturning resistant seamless interchange motor speed regulating control system, which comprises a rectifier, a boost chopper, an inverter-overturning resistant protecting unit and an SCR inverter. The system is adaptable to asynchronous motors with common windings and internal feedback windings, cage winding type brushless double-fed motors and cage winding type internal feedback brushless motors, and resolves problems of inverter overturning caused by great reduction or instant elimination of network voltage. The inverter-overturning resistant protecting unit prevents generating inverter overturning when the network voltage is greatly reduced or eliminated instantly, realizes seamless interchange of an inverter circuit and a protecting link, and keeps rotation speed of the motor unchanged basically. The inverter-overturning resistant seamless interchange motor speed regulating control system is particularly adaptable to occasions utilizing production technique without permitting rotation speed of equipment waving obviously, and is high in system reliability and simple and convenient in control.
Description
Technical field
The utility model relates to ac motor speed control control technology field, particularly a kind of speed adjustment control system of anti-inversion failure seamless switching motor.
Background technology
The mesohigh motor is widely used in dragging of blower fan and water pump, if can utilize speed governing to realize that air quantity and hydraulic pressure regulates, then can save a large amount of electric energy, so market is very vigorous to the demand of the moderate mesohigh governing system of function admirable, cost.
Develop the chopped mode rotor frequency conversion speed-adjusting system in recent years, a kind of IGBT inverter middle voltage electromotor chopped mode dual DSP digital governing system is disclosed as Chinese patent CN200710122573.1, uncontrollable rectifier of its motor rotor side joint and thyristor inverter, between rectifier and inverter, add the first class boost chopper, it is constant that the triggering phase shift advance angle β of thyristor during work (SCR) inverter is fixed on minimum value, dc inversion voltage is fixed, recently change rotor voltage (frequency) by the duty that changes chopper, realize speed governing.This chopped mode rotor frequency conversion speed-adjusting system is than traditional tandem control power factor height, and harmonic wave is little.But; the SCR inverter reduces suddenly or Xiao Shi Time significantly at line voltage; being easy to take place inversion overturns; damage equipment; although original system has been provided with anti-inversion stalling protection; but find by actual the use; still there are following two problems in chopped mode rotor frequency conversion speed-adjusting system originally: at electric network fault or with the big motor starting of electrical network supply power voltage is reduced or Xiao Shi Time significantly suddenly; inversion will take place and overturn in the SCR inverter; this moment, anti-inversion stalling protection started; inversion circuit is disconnected; short circuit rotor DC loop so motor speed rises near at full speed, is promptly overturned in the transition in anti-inversion simultaneously; the velocity perturbation of equipment is very big, and the production process that has is unallowed.The disconnection of inversion circuit realizes with the IGBT pipe; and short circuit rotor DC loop is finished by SCR; because the time difference problem of IGBT and SCR response; changing-over moment tends to cause overvoltage and overcurrent and starts over-voltage over-current protection; the excision governing system changes at full speed or the water resistance speed governing operation; even excessive electric current can make the high-voltage switch gear tripping grinder, seriously influences production, increases labor intensity of operating personnel.
As shown in Figure 1, be existing chopped mode rotor frequency conversion speed-adjusting system main circuit diagram, the protection that its anti-inversion is overturned is realized by the IGBT and the SCR in parallel with rectifier bridge that are connected on DC loop, when line voltage is crossed low or inverter current when excessive, conducting SCR disconnects IGBT simultaneously, though disconnected inversion circuit this moment, can prevent the development that inversion is overturned, but the motor rotor loop is short circuit owing to the conducting of SCR, then motor accelerates to full speed running, may produce the unallowed velocity perturbation of equipment; In addition, the switching time of IGBT is fast more than SCR's, cooperates when bad, and the disconnection of IGBT is before the SCR conducting, and then the rotor winding can be responded to high voltage, causes system to trip because of over-voltage and over-current, even damage equipment.
The utility model content
The purpose of this utility model provides a kind of speed adjustment control system of anti-inversion failure seamless switching motor, to solve because of the problem that line voltage significantly reduces or the moment that disappears causes inversion to be overturned, makes the velocity perturbation minimum of equipment.
For achieving the above object; the utility model provides a kind of speed adjustment control system of anti-inversion failure seamless switching motor; comprise electric motor system; governing system and control system; described governing system respectively with described electric motor system; control system connects; described electric motor system is connected with described control system; described governing system comprises uncontrollable rectifier; boost chopper; contactor and inverter; described boost chopper comprises first inductance; first diode; first electric capacity; first field-effect transistor; between described boost chopper and described inverter, also be connected with the anti-inversion failure protected location and second inductance
Described anti-inversion failure protected location comprises second field-effect transistor; the 7th resistance; the 8th diode; thyristor; fast diode; the 9th resistance; the 9th diode; the 3rd electric capacity; the 8th resistance; the tenth diode and the 3rd field-effect transistor; the base stage of described second field-effect transistor is connected with described control system; the drain electrode of described second field-effect transistor respectively with an end of described the 7th resistance; the input of described thyristor; described the 8th diode input connects; the other end of described the 7th resistance respectively with the output of described the 8th diode; the input of described fast diode; the output of described the tenth diode connects; the output of described fast diode is connected with the input of described the 9th diode by the 9th resistance; the output of the output of described thyristor and described the 9th diode respectively with an end of described the 3rd electric capacity; one end of described the 8th resistance connects; the source electrode of described second field-effect transistor respectively with the output of described thyristor; the other end of described the 3rd electric capacity; the other end of described the 8th resistance is connected with the source electrode of described the 3rd field-effect transistor; the drain electrode of described the 3rd field-effect transistor is connected with the input of described the tenth diode; the base stage of described the 3rd field-effect transistor is connected with described control system; described inverter is connected with the drain electrode of described the 3rd field-effect transistor by described second inductance, and described contactor is connected with described inverter with described electric motor system respectively.
Speed adjustment control system of anti-inversion failure seamless switching motor of the present utility model, described the 7th resistance is high-power resistance, and the setting rotating speed of the motor of its resistance and described electric motor system coupling.
Speed adjustment control system of anti-inversion failure seamless switching motor of the present utility model is connected with contravariant transformer between described contactor and described electric motor system.
Speed adjustment control system of anti-inversion failure seamless switching motor of the present utility model, described control system replace with DSP or single-chip microcomputer or DSP+PLC or single-chip microcomputer+PLC.
During comprising, speed adjustment control system of anti-inversion failure seamless switching motor of the present utility model, described motor press conventional wound asynchronous motor, middle pressure internal feedback wire wound asynchronous motor, middle pressure around cage brushless double-fed motor and middle pressure cage internal feedback brushless motor.
The anti-inversion failure protected location of speed adjustment control system of anti-inversion failure seamless switching motor of the present utility model can be guaranteed when significantly reducing because of line voltage moment or disappearing; unlikely generation inversion is overturned; and the seamless switching of realization inverter circuit and protection link; motor speed remains unchanged substantially; being specially adapted to production technology does not allow the equipment rotating speed that the occasion of obvious fluctuation is arranged; the system reliability height is controlled simple and convenient.
Description of drawings
Fig. 1 is the main circuit schematic diagram of existing chopped mode rotor frequency conversion speed-adjusting system:
Fig. 2 is the circuit theory diagrams that are used for the speed adjustment control system of anti-inversion failure seamless switching motor of pressure conventional wound asynchronous motor of the present utility model;
Fig. 3 is the main circuit schematic diagram of anti-inversion failure protected location NFD among Fig. 2;
Fig. 4 is an anti-inversion failure seamless switching motor method for controlling speed regulation flow chart of the present utility model;
Fig. 5 is the main circuit schematic diagram that is used for the speed adjustment control system of anti-inversion failure seamless switching motor of pressure internal feedback wire wound asynchronous motor of the present utility model;
Fig. 6 is the main circuit schematic diagram that is used for pressing around the speed adjustment control system of anti-inversion failure seamless switching motor of cage brushless double-fed motor of the present utility model;
Fig. 7 is the main circuit schematic diagram that is used for the speed adjustment control system of anti-inversion failure seamless switching motor of pressure cage internal feedback brushless motor of the present utility model.
Embodiment
Be described below in conjunction with the embodiment of Figure of description speed adjustment control system of anti-inversion failure seamless switching motor of the present utility model:
Referring to figs. 2 and 3, the speed adjustment control system of anti-inversion failure seamless switching motor that is used for pressure conventional wound asynchronous motor of the present utility model comprises: comprise electric motor system MD, governing system FC and control system PLC, governing system FC respectively with electric motor system MD, control system PLC connects, electric motor system MD is connected with control system PLC, governing system FC comprises uncontrollable rectifier DR, boost chopper BC, contactor KM4 and inverter TI, boost chopper BC comprises the first inductance L S1, the first diode SD1, first capacitor C, the first field-effect transistor 1CS, the end of the first inductance L S1 is connected with the end of uncontrollable rectifier DR, the other end of the first inductance L S1 respectively with the end of the first diode SD1, the drain electrode of the first field-effect transistor 1CS connects, the other end of the first diode SD1 respectively with an end of first capacitor C, inverter TI connects, the other end of uncontrollable rectifier DR respectively with the source electrode of the first field-effect transistor 1CS, the other end of first capacitor C, inverter TI connects, the base stage of the first field-effect transistor 1CS is connected with control system PLC, and contactor KM4 is connected with inverter TI with electric motor system MD respectively.
Wherein, governing system FC also comprises the anti-inversion failure protected location NFD and the second inductance L S2; anti-inversion failure protected location NFD comprises the second field-effect transistor 2CS; the 7th resistance R 7; the 8th diode D8; thyristor SCR; fast diode BOD; the 9th resistance R 9; the 9th diode D9; the 3rd capacitor C 3; the 8th resistance R 8; the tenth diode D10 and the 3rd field-effect transistor 3CS; the base stage of the second field-effect transistor 2CS is connected with control system PLC; the drain electrode of the second field-effect transistor 2CS respectively with an end of the 7th resistance R 7; the input of thyristor SCR; the 8th diode D8 input connects; the other end of the 7th resistance R 7 respectively with the output of the 8th diode D8; the input of fast diode BOD; the output of the tenth diode D10 connects; the output of fast diode BOD is connected with the input of the 9th diode D9 by the 9th resistance R 9; the output of the output of thyristor SCR and the 9th diode D9 respectively with an end of the 3rd capacitor C 3; one end of the 8th resistance R 8 connects; the source electrode of the second field-effect transistor 2CS respectively with the output of thyristor SCR; the other end of the 3rd capacitor C 3; the other end of the 8th resistance R 8 is connected with the source electrode of the 3rd field-effect transistor 3CS; the drain electrode of the 3rd field-effect transistor 3CS is connected with the input of the tenth diode D10; the 3rd field-effect transistor 3CS base stage is connected with control system PLC, and inverter TI is connected with the drain electrode of the 3rd field-effect transistor 3CS by the second inductance L S2.
Wherein, speed adjustment control system of anti-inversion failure seamless switching motor of the present utility model, the 7th resistance R 7 is a high-power resistance, and the setting rotating speed of the motor of its resistance and electric motor system MD coupling.
Wherein, speed adjustment control system of anti-inversion failure seamless switching motor of the present utility model is connected with contravariant transformer Taw between contactor KM4 and electric motor system MD.
Speed adjustment control system of anti-inversion failure seamless switching motor of the present utility model, control system PLC replace with DSP or single-chip microcomputer or DSP+PLC or single-chip microcomputer+PLC.
Wherein, the second field-effect transistor 2CS, the 3rd field-effect transistor 3CS is complete controlled insulated door bipolar transistor IGBT, when motor moves at rotor frequency conversion speed-adjusting, monitor inverter or line voltage and inverter current in real time, set minimum value or power network current and surpass when setting maximum when line voltage drops to, the instant conducting second field-effect transistor 2CS, turn-off the 3rd field-effect transistor 3CS then, and the triggering signal of blocking boost chopper BC, because the second field-effect transistor 2CS branch road string has the 7th resistance R 7, so the time motor rotor DC loop be serial-resistance speed-regulation operation rather than rotor short-circuit full speed running, and the fluctuation of rotating speed is very little during changing-over.Often voltage ripple of power network is of short duration generation, for example the large capacity motor with electrical network starts moment, through blink, if it is normal that voltage recovers, system is the automatic reverse changing-over, conducting the 3rd field-effect transistor 3CS, disconnect the second field-effect transistor 2CS, the triggering signal of open boost chopper BC, motor recovers the rotor frequency conversion speed-adjusting state, and same transition velocity perturbation is very little.If in official hour, voltage still can not reach normal value, and then system is automatically brought to liquid resistance device FR speed governing operation, because liquid resistance device FR speed governing is the real-time tracking rotor frequency conversion speed-adjusting, so also velocity perturbation can not occur.
With reference to figure 4; anti-inversion failure seamless switching motor method for controlling speed regulation of the present utility model; this method is monitored inverter voltage or line voltage and power network current in real time, when unusual, start and drops into the anti-inversion failure protected location; at the appointed time; if it is normal that voltage recovers, then excise the anti-inversion failure protected location automatically, otherwise be transformed into liquid resistance device FR speed governing; the switching of three kinds of running statuses obvious speed all do not occur and changes, and its job step is described in detail as follows:
1), governing system just often; the second field-effect transistor 2CS conducting of anti-inversion failure protected location NFD; the 3rd field-effect transistor 3CS disconnects, and is equivalent to not start drop into the anti-inversion failure protected location, and the rotor DC loop of the motor of electric motor system MD is the frequency control operating state.
2), control system PLC judges whether current line voltage is less than or equal to the setting minimum value, if be less than or equal to the setting minimum value, then execution in step 4, otherwise, execution in step 3.
3), control system PLC judges current power network current whether more than or equal to setting maximum, if more than or equal to setting maximum, then execution in step 4, otherwise, execution in step 2.
4), control system PLC judges that governing system is the A-stage that inversion is overturned; closed the 3rd field-effect transistor 3CS; disconnect the second field-effect transistor 2CS; block the triggering signal of the first field-effect transistor 1CS; inverter TI disconnects from the rotor DC loop; start anti-inversion failure protected location NFD, the motor of electric motor system MD carries out speed switching, generation and the development of avoiding inversion to overturn.
5), the rotor of the motor of electric motor system MD keeps the preceding speed running of switching; the 2CS branch road string of anti-inversion failure protected location NFD has high-power the 7th resistance R 7; when the anti-inversion failure protected location starts; be equivalent to motor rotor crosstalk resistance operation; the 7th resistance R 7 has been selected suitable resistance value for use; can make the rotating speed and the changing-over of motor quite preceding, rotating speed can not produce tangible fluctuation.
6), control system PLC judges that whether current electrical network piezoelectric voltage recovered normal in predetermined 60 seconds, if recover normal, then execution in step 7, otherwise, execution in step 8.
7), closed the 3rd field-effect transistor 3CS of control system PLC; disconnect the second field-effect transistor 2CS; recover the triggering signal of the first field-effect transistor 1CS; inverter TI conducting; close anti-inversion failure protected location NFD; the motor of electric motor system MD carries out the speed counter-rotating and connects, and switches back the frequency control operating state.
8), control system PLC judges that whether current electrical network piezoelectric voltage recovered normal in predetermined 180 seconds, if recover normal, then execution in step 9, otherwise, execution in step 6.
9), control system PLC switches to adjustable liquid resistance device speed governing state with the motor of electric motor system MD.Do not recover yet normally when surpassing 180 second time line voltage stipulating, then system automatically switches to the speed governing of adjustable liquid resistance device, because liquid resistance speed regulator is always followed the tracks of rotor frequency conversion speed-adjusting, so realized seamless switching equally.
Be suitable for the drive motor with governing system of the present utility model four classes are arranged: middle pressure conventional wound asynchronous motor (see figure 2), middle pressure internal feedback wire wound asynchronous motor (see figure 5), middle pressure are around cage brushless double-fed motor (see figure 6) and middle pressure cage internal feedback brushless motor (see figure 7).
Speed adjustment control system of anti-inversion failure seamless switching motor of the present utility model has solved the problem because of line voltage significantly reduces or the moment that disappears causes inversion to be overturned; its anti-inversion failure protected location is guaranteed when significantly reducing because of line voltage moment or disappearing; unlikely generation inversion is overturned; and the seamless switching of realization inverter circuit and protection link; motor speed remains unchanged substantially; being specially adapted to production technology does not allow the equipment rotating speed that the occasion of obvious fluctuation is arranged; the system reliability height is controlled simple and convenient.
Above embodiment is described preferred implementation of the present utility model; be not that scope of the present utility model is limited; under the prerequisite that does not break away from the utility model design spirit; various distortion and improvement that the common engineers and technicians in this area make the technical solution of the utility model all should fall in the definite protection range of claims of the present utility model.
Claims (5)
1, a kind of speed adjustment control system of anti-inversion failure seamless switching motor, comprise electric motor system (MD), governing system (FC) and control system (PLC), described governing system (FC) respectively with described electric motor system (MD), control system (PLC) connects, described electric motor system (MD) is connected with described control system (PLC), described governing system (FC) comprises uncontrollable rectifier (DR), boost chopper (BC), contactor (KM4) and inverter (TI), described boost chopper (BC) comprises first inductance (LS1), first diode (SD1), first electric capacity (C), first field-effect transistor (1CS), it is characterized in that
Between described boost chopper (BC) and described inverter (TI), also be connected with anti-inversion failure protected location (NFD) and second inductance (LS2),
Described anti-inversion failure protected location (NFD) comprises second field-effect transistor (2C8); the 7th resistance (R7); the 8th diode (D8); thyristor (SCR); fast diode (BOD); the 9th resistance (R9); the 9th diode (D9); the 3rd electric capacity (C3); the 8th resistance (R8); the tenth diode (D10) and the 3rd field-effect transistor (3CS); the base stage of described second field-effect transistor (2CS) is connected with described control system (PLC); the drain electrode of described second field-effect transistor (2CS) respectively with an end of described the 7th resistance (R7); the input of described thyristor (SCR); described the 8th diode (D8) input connects; the other end of described the 7th resistance (R7) respectively with the output of described the 8th diode (D8); the input of described fast diode (BOD); the output of described the tenth diode (D10) connects; the output of described fast diode (BOD) is connected with the input of described the 9th diode (D9) by the 9th resistance (R9); the output of the output of described thyristor (SCR) and described the 9th diode (D9) respectively with an end of described the 3rd electric capacity (C3); one end of described the 8th resistance (R8) connects; the source electrode of described second field-effect transistor (2CS) respectively with the output of described thyristor (SCR); the other end of described the 3rd electric capacity (C3); the other end of described the 8th resistance (R8) is connected with the source electrode of described the 3rd field-effect transistor (3CS); the drain electrode of described the 3rd field-effect transistor (3CS) is connected with the input of described the tenth diode (D10); the base stage of described the 3rd field-effect transistor (3CS) is connected with described control system (PLC); described inverter (TI) is connected by the drain electrode of described second inductance (LS2) with described the 3rd field-effect transistor (3CS), and described contactor (KM4) is connected with described inverter (TI) with described electric motor system (MD) respectively.
2, speed adjustment control system of anti-inversion failure seamless switching motor according to claim 1 is characterized in that,
Described the 7th resistance (R7) is high-power resistance, and the setting rotating speed of the motor of its resistance and described electric motor system (MD) coupling.
3, speed adjustment control system of anti-inversion failure seamless switching motor according to claim 2 is characterized in that,
Between described contactor (KM4) and described electric motor system (MD), be connected with contravariant transformer (Taw).
4, speed adjustment control system of anti-inversion failure seamless switching motor according to claim 3 is characterized in that,
Described control system (PLC) replaces with DSP or single-chip microcomputer or DSP+PLC or single-chip microcomputer+PLC.
5, speed adjustment control system of anti-inversion failure seamless switching motor according to claim 4 is characterized in that,
During comprising, described motor press conventional wound asynchronous motor, middle pressure internal feedback wire wound asynchronous motor, middle pressure around cage brushless double-fed motor and middle pressure cage internal feedback brushless motor.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN2009201519015U CN201422099Y (en) | 2009-04-30 | 2009-04-30 | Inverter-overturning resistant seamless interchange motor speed regulating control system |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN2009201519015U CN201422099Y (en) | 2009-04-30 | 2009-04-30 | Inverter-overturning resistant seamless interchange motor speed regulating control system |
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| Publication Number | Publication Date |
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| CN201422099Y true CN201422099Y (en) | 2010-03-10 |
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| Application Number | Title | Priority Date | Filing Date |
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| CN2009201519015U Expired - Lifetime CN201422099Y (en) | 2009-04-30 | 2009-04-30 | Inverter-overturning resistant seamless interchange motor speed regulating control system |
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101527539B (en) * | 2009-04-30 | 2011-01-05 | 广东华拿东方能源有限公司 | Speed adjustment control system of anti-inversion failure seamless switching motor and control method thereof |
| CN104656603A (en) * | 2014-01-13 | 2015-05-27 | 湖北新百特自动化设备股份有限公司 | Solid-state starting and speed regulation device with closed loop control function for wound-rotor motor |
-
2009
- 2009-04-30 CN CN2009201519015U patent/CN201422099Y/en not_active Expired - Lifetime
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101527539B (en) * | 2009-04-30 | 2011-01-05 | 广东华拿东方能源有限公司 | Speed adjustment control system of anti-inversion failure seamless switching motor and control method thereof |
| CN104656603A (en) * | 2014-01-13 | 2015-05-27 | 湖北新百特自动化设备股份有限公司 | Solid-state starting and speed regulation device with closed loop control function for wound-rotor motor |
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| Date | Code | Title | Description |
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| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant | ||
| AV01 | Patent right actively abandoned |
Granted publication date: 20100310 Effective date of abandoning: 20090430 |