CN203006774U - Electrical control system of quenching crane applying stator variable voltage variable speed device - Google Patents
Electrical control system of quenching crane applying stator variable voltage variable speed device Download PDFInfo
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- CN203006774U CN203006774U CN 201220661029 CN201220661029U CN203006774U CN 203006774 U CN203006774 U CN 203006774U CN 201220661029 CN201220661029 CN 201220661029 CN 201220661029 U CN201220661029 U CN 201220661029U CN 203006774 U CN203006774 U CN 203006774U
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- stator
- contactless switch
- adjusting device
- pressure regulating
- speed adjusting
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Abstract
The utility model discloses an electric control system of a quenching crane applying a stator variable voltage variable speed device. The electric control system comprises a separate excitation power brake device and a stator variable voltage variable speed device, wherein when in a common working mode, rising and falling of a hoisting mechanism are respectively controlled by a variable voltage variable speed device; when in a quenching working mode, control by the stator variable voltage variable speed device is changed into the control by the separate excitation power brake device while the hoisting mechanism drops to a preset gear; and in a conversion period, rotor frequency feedback of a motor is normally connected, and the output terminal of the stator variable voltage variable speed device does not output. By implementing the technical scheme of the utility model, the electric control system disclosed by the utility model has the beneficial effects that the stator variable voltage variable speed device is added in a quenching crane control system in the prior art, when in the quenching working mode, and the control by the stator variable voltage variable speed device is changed into the control by the separate excitation power brake device while the hoisting mechanism drops to the preset gear, so that a workpiece can be quickly, steadily and accurately hoisted to a quenching tank and the workpiece can quickly stop when the workpiece is under liquid level.
Description
Technical field
The utility model relates to motor electric control system field, be a kind of industry spot that is widely used in adopting stator pressure regulating speed adjusting device and the mutual switching controls motor of separate excitation power-absorption unit, especially Crane Industry adopts stator pressure regulating speed adjusting device and the load of the mutual switching controls motor of separate excitation power-absorption unit fast-descending to reach the electric control system of Quenching Treatment.
Background technology
Hoisting crane is a kind of electromechanical appliance that takes weight by vertical lift or vertical lift and parallel motion.Quenching crane is used for the handling mechanical workpieces to carry out quenching technical and processes, hoisting crane can be fast with workpiece from the heating furnace handling to quenching bath, require the command speed fast-descending with 2 times when descending.Based on the particularity of quenching technical, require lifting mechanism can realize the command speed fast-descending of 2 times, and can be at the fast state accurate stopping, do not produce and slip the hook phenomenon.Simultaneously also require the operating unit starting and braking of quenching crane to operate steadily, and can quick and precisely stop at the station place of requirement.
The ascent direction of lifting mechanism all adopts rotor crosstalk resistance mode in electrical control, the mechanical specialities of motor is softer, so deceleration and stopping performance plays in mechanism and the speed governing actual effect is unsatisfactory, is difficult to the accurate handling of workpiece quick and stable to well formula quenching bath; Adopt the dynamic brake mode at descent direction, speed adjustable range is little, plays deceleration and stopping performance not bery desirable.When equipment is operated in quenching gear (quick gear descends), according to the quenching technical requirement, workpiece enters and requires under liquid level to stop fast, do not slip hook for guaranteeing to stop at a high speed, stator need to inject very large electric current and carry out dynamic brake (resistance braking), this electric current far surpasses the motor load current value, can cause harmful effect to motor and complete machine control system.
Fig. 1 is the structural representation of the quenching crane control system of prior art, as shown in the figure.In the 380V AC network, the input end of separate excitation power-absorption unit is connected with two main contacts of contactless switch KM31, the mouth of separate excitation power-absorption unit is connected with 1 master control point of contactless switch KM31, after contactless switch KM1 ', contactless switch KM2 ', contactless switch KM31 ' are in parallel and motor M ' stator side be connected, motor M ' rotor-side connect three groups of current limliting networks, described current limliting network is composed in series by resistance and contactless switch, three groups of current limliting networks in figure are respectively: first group of current limliting network, KM40 ' and R4 ' parallel connection; Second group of current limliting network, KM41 ' and R3 ' parallel connection; The 3rd group of current limliting network, KM42 ' and R2 ' parallel connection; The 4th group of current limliting network directly seals in resistance R 1 '.
The ascent direction serial-resistance speed-regulation descends and to take the crosstalk resistance to be combined control with dynamic brake.When giving climb command, KM1 ' adhesive, rotor KM40 ', KM41 ', the 1KM42 ' adhesive of delaying time; When providing the decline instruction, KM2 ' adhesive, rotor KM40 ', KM41 ', the KM42' adhesive of delaying time, during near quenching bath, the driver feeds the dynamic brake instruction when workpiece, and KM2 ' disconnects KM31 ' adhesive.
Due to the ascent direction of lifting mechanism, all adopt rotor crosstalk resistance mode in electrical control, the mechanical specialities of motor is softer, so deceleration and stopping performance plays in mechanism and the speed governing actual effect is unsatisfactory, is difficult to the accurate handling of workpiece quick and stable to well formula quenching bath; And adopting rotor crosstalk resistance and dynamic brake mode at descent direction, speed adjustable range is little, plays deceleration and stopping performance not bery desirable.When equipment is operated in quenching gear (quick gear descends), according to the quenching technical requirement, workpiece enters and requires under liquid level to stop fast, do not slip hook for guaranteeing to stop at a high speed, stator need to inject very large electric current and carry out dynamic brake (resistance braking), this electric current far surpasses the motor load current value, can cause harmful effect to motor and complete machine control system.
Present application about the quenching crane electric operation system, for the quenching crane electric operation system that field working conditions is abominable, the quenching tonnage is large, speed adjustable range is wide, little to electromechanical shock, also lack a kind of actv. mode of speed control, solve existing problem, satisfy the theory demand of quenching.
Summary of the invention
The utility model is for the proposition of above problem, and develops the electric control system that a kind of stator pressure regulating speed adjusting device is applied to quenching crane.
a kind of stator pressure regulating speed adjusting device is applied to the electric control system of quenching crane, it is characterized in that, comprise separate excitation power-absorption unit and stator pressure regulating speed adjusting device, the input end of stator pressure regulating speed adjusting device is connected with power supply, the mouth of stator pressure regulating speed adjusting device is connected with contactless switch KM1, the input end of separate excitation power-absorption unit is connected with two main contacts of contactless switch KM31, the mouth of separate excitation power-absorption unit is connected with 1 master control point of contactless switch KM31, contactless switch KM1, contactless switch KM2, be connected with the stator side of motor after contactless switch KM31 parallel connection, the rotor-side of motor connects at least one group of current limliting network, described current limliting network is composed in parallel by resistance and contactless switch, last group current limiting net directly seals in resistance, wherein, contactless switch KM1 and contactless switch KM2 are with mechanical interlocked forward and reverse contactless switch, when normal mode of operation, the rising of hoist mechanism and decline are controlled by pressure-speed regulating device, when quencher's operation mode, when hoist mechanism drops to predetermined gear, controlled by stator pressure regulating speed adjusting device and be converted to the control of separate excitation engine installation, in the transition period, the motor rotor frequency feedback is normal to be connected, and the mouth of stator pressure regulating speed adjusting device is not exported.
Implement the technical solution of the utility model and have following beneficial effect: by add stator pressure regulating speed adjusting device in the quenching crane control system of prior art, when normal mode of operation, the rising of hoist mechanism and decline are controlled by pressure-speed regulating device; When quencher's operation mode, when hoist mechanism drops to predetermined gear, controlled by stator pressure regulating speed adjusting device and be converted to the control of separate excitation engine installation, make workpiece can the accurate handling of quick and stable to quenching bath, and can guarantee to stop fast when workpiece is under entering liquid level, guarantee that hoist mechanism stops at a high speed not slip hook.
Description of drawings
Fig. 1 is the structural representation of the quenching crane control system of prior art;
Fig. 2 is the structural representation of an embodiment of the present utility model;
Fig. 3 is control flow chart of the present utility model.
The specific embodiment
The purpose of this utility model is to provide the electric control system of a kind of stator pressure regulating speed adjusting device and the mutual switch operating of separate excitation power-absorption unit, to solve Crane Industry quench, inefficiency high with the cost that exists in the hoisting crane prior art, position control inaccuracy, the problem that speed adjusting performance is undesirable.
Electric control system solution provided by the utility model is: electric control system comprises separate excitation power-absorption unit and stator pressure regulating speed adjusting device, and when normal mode of operation, the rising of hoist mechanism and decline are controlled by pressure-speed regulating device; When quencher's operation mode, when hoist mechanism drops to predetermined gear, controlled by stator pressure regulating speed adjusting device and be converted to the control of separate excitation engine installation, in the transition period, the motor rotor frequency feedback is normal to be connected, and the mouth of stator pressure regulating speed adjusting device is not exported.
Separate excitation power-absorption unit, i.e. separate excitation power-absorption unit.Stator voltage controlling is speed regulation device, i.e. stator voltage and speed governing by transistor device.
Be that normal mode of operation and quenching velocity service condition are under quencher's operation mode in the conventional speeds service condition, the handoff-security electric-control system between stator pressure regulating speed adjusting device controlling run and separate excitation power-absorption unit controlling run.
Fig. 2 is the structural representation of an embodiment of the present utility model, as shown in Figure 2, in the 380V AC network, the input end of stator pressure regulating speed adjusting device is connected with power supply, the mouth of stator pressure regulating speed adjusting device is connected with contactless switch KM1, the input end of separate excitation power-absorption unit is connected with two main contacts of contactless switch KM31, the mouth of separate excitation power-absorption unit is connected with 1 master control point of contactless switch KM31, contactless switch KM1, contactless switch KM2, be connected with the stator side of motor M after contactless switch KM31 parallel connection, the rotor-side of motor M connects four groups of current limliting networks, described current limliting network is composed in parallel by resistance and contactless switch, last group current limiting net is connected with resistance, contactless switch KM1 and contactless switch KM2 are with mechanical interlocked forward and reverse contactless switch.Described four groups of current limliting networks are respectively: first group of current limliting network, and KM40 and R5 are in parallel; Second group of current limliting network, KM41 and R4 are in parallel; The 3rd group of current limliting network, KM42 and R3 are in parallel; The 4th group of current limliting network, KM43 and R2 are in parallel; The 5th group of current limliting network directly imports resistance R 1 into.
Under normal mode of operation, the rise and fall of mechanism are controlled by stator pressure regulating speed adjusting device.
Under quencher's operation mode, the rising of mechanism and descend one, two, stator pressure regulating speed adjusting device drives during third gear, during the decline fourth gear, controlled by separate excitation power-absorption unit (hereinafter to be referred as quenching unit), speed reaches 200% of command speed, and the energy smooth operation, and particular content is as follows:
When 1, rising, stator pressure regulating speed adjusting device normally moves.From zero-bit to descending one grade the time, stator pressure regulating speed adjusting device is carried out the one grade of order that descends; When the decline second gear, stator pressure regulating speed adjusting device is carried out the order of decline second gear; During the decline third gear, stator pressure regulating speed adjusting device is carried out the decline fourth gear order under normal mode of operation; When the decline fourth gear, stator pressure regulating speed adjusting device is not worked, and descends by quenching unit driving work; When the decline fourth gear was got back to each grade of decline and zero-bit, stator pressure regulating speed adjusting device was not all worked.
2, when first three shelves that descend arrived the decline fourth gear, the output of stator pressure regulating speed adjusting device was blocked immediately, stator pressure regulating speed adjusting device major loop no current, and output relay disconnects immediately, and stator pressure regulating speed adjusting device is not worked.Cui Huo Installed puts by getting after the contactless switch adhesive electric, obtains the instruction of quenching, and can reduce the resistance braking electric current, until satisfy the goal pace that its inner PID regulates.
3, at stator pressure regulating speed adjusting device to the quenching unit transition period, motor rotor frequency feedback is normal to be connected, but the stator pressure regulating speed adjusting device mouth is not exported on request.
4, after master controller returns zero-bit, descend 1,2,3 grades through again shifting onto in 2 seconds, stator pressure regulating speed adjusting device is resumed work.
During with interior operation, adopt stator pressure regulating speed adjusting device to control at motor 100% command speed, pressure-speed regulating device is controlled the silicon controlled make-and-break time by changing its inner SCR Trigger Angle degree, and then changes the alternating-current voltage/AC voltage on motor stator.When regulating stator voltage, by the adhesive of rotor contactless switch with disconnect the resistance that changes rotor, carry out speed adjustment, the electric voltage frequency that pressure-speed regulating device can gather rotor-side calculates the final percentum of motor speed, by following formula:
f
1=s·f
2 （0-1）
In formula, f
1Be motor stator frequency, f
2Be motor rotor frequency, s is motor slip ratio
n=（1-s）n
0 （0-2）
In formula, n is the current rotating speed of motor
n%=n/n
0（0-3）
In formula, n% is the percentum that pressure-speed regulating device shows, n
0Synchronous speed for motor.
Calculate motor present speed percentum, form feedback, and carry out closed-loop process by the PID treater of stator pressure regulating speed adjusting device inside, finally reach goal pace.
When quenching, rotating speed can reach 200% command speed, and at this moment KM1 and KM2 can first disconnect, KM31 meeting adhesive, and motor passes into direct current (DC), and motor enters the resistance braking state.The separate excitation power-absorption unit is connected to the voltage signal of the permanent magnetic flow direct current tachogenerator feedback on the motor high speed shaft by detection, its feedback voltage formula is as follows:
E=B·L·V （0-4）
In formula, E is induced electric motive force, and B is magnetic flux, and L is cutting magnetic induction line metal effective length, and V is the normal velocity of cutting magnetic induction line.
Can calculate the actual speed of motor
n=E·n
DC/E
NDC （0-5）
In formula, n is the alternating current dynamo actual speed, and E is feedback voltage, E
NDCBe the rated voltage of DC tachometer generator, n
DCRated speed of rotation for DC tachometer generator.
The separate excitation power-absorption unit passes through its inner PID link, the direct current (DC) that the regulating electric machine stator passes into, and the rotor side is come Switch Rotor resistance by the adhesive of control loop control contactor, reaches the rotating speed of expection.And by KM1, KM2 and KM31 can effectively prevent the alternating current-direct current short circuit at the electrical interlocks of control loop design.
The control logic of the specific implementation of the technical solution of the utility model is summarized as follows:
1, when gear is got to 1,2,3 grades of ascent direction, rotor contactless switch KM40, the KM41 adhesive is risen 4 grades the time when getting to, KM42, KM43 controls adhesive by device.
2, when gear is got to 1,2 grade of descent direction, rotor contactless switch KM40 adhesive this moment, KM41, KM42, KM43 opens, descends 3 grades the time, the device high-speed cruising, KM42, KM43 is by device control adhesive.Then instruction is shifted onto 4 grades of declines, regulator blocks output, the quenching unit action.
When 3, decline fourth gear is returned third gear or second gear (during quenching, decline two, third gear are same gear, during switching without any changing), still controlled by quenching unit, this moment, KM40 postponed the 150ms adhesive, KM41 postpones 800ms adhesive (delay time is according to the corresponding increase and decrease of different motors meeting), and the velocity-stabilization of third gear is in 20% left and right.
4, decline fourth gear is to descending one grade the time, rotor contactless switch KM40 adhesive immediately, and KM41 postpones 300ms, KM42 delay 600ms adhesive.
When 5, decline fourth gear directly returned zero, drg was reported lock immediately.
Fig. 3 is control flow chart of the present utility model, as shown in the figure, when hoist mechanism begins to move, first judges direction of action, when direction of action when hoisting direction, controlled 0 → 1,2,3 grades by stator pressure regulating speed adjusting device, the KM1 adhesive, KM40, KM41 keeps adhesive, and drg is opened a sluice gate; 1,2,3 → 4 latch devices are controlled adhesive KM42 successively, KM43; KM1, KM41, KM40 keeps adhesive; 4 → 3,2,1 latch devices are controlled and are disconnected simultaneously KM43, KM42, and KM1, KM41, KM40 keeps adhesive; 3,2,1 → 0 grade, KM1 disconnects, KM40, and KM41 keeps adhesive, and drg closes a floodgate; When direction of action is descent direction, judge current mode of operation, when mode of operation is non-quencher's operation mode, when being normal mode of operation, 0 → 1,2,3 grades, the first adhesive of KM1, if load is underloading, KM1 disconnects the KM2 adhesive, if heavy duty, KM1 keeps adhesive.KM40, KM41 disconnects; 1,2,3 → 4 grades, the KM2 adhesive, device is controlled adhesive KM42 successively, KM43; 4 → 1,2,3 grades, device is controlled and is disconnected simultaneously KM42, KM43, and the first adhesive of KM1, if load is underloading, KM1 disconnects the KM2 adhesive, if heavy duty, KM1 keeps adhesive; 3,2,1 → 0 grade, KM1, KM2 disconnects, KM40, KM41 keeps adhesive, and drg closes a floodgate.When direction of action is descent direction and mode of operation during for quencher's operation mode, 0 → 1,2 grades, the first adhesive of KM1, if load is underloading, KM1 disconnects the KM2 adhesive, if heavy duty, KM1 keeps adhesive.KM40, KM41 disconnects; 1,2 → 3 grades, the KM2 adhesive, device is controlled adhesive KM42 successively, KM43; 3 → 4 grades, KM1, KM2 disconnects the KM31 adhesive, KM40, KM41, KM42, KM43 all disconnects; 4 → 3,2 grades of KM40, KM41 is adhesive successively, and other contactless switchs are kept disconnection; 3,2 → 1 grade of KM42, KM43 is adhesive successively, and other contactless switchs are kept disconnection; 1 → 0 grade, close a floodgate immediately; After master controller returns zero-bit, descend 1,2,3 grades through again shifting onto in 2 seconds, stator pressure regulating speed adjusting device is resumed work.
In order to make the purpose of this utility model, technical scheme and advantage clearer, below in conjunction with drawings and Examples, the utility model is further elaborated.Should be appreciated that specific embodiment described herein only in order to explaining the utility model, and be not used in restriction the utility model.
Embodiment of the present utility model:
Every quenching crane main hoisting mechanism is comprised of following equipment:
1. electrical motor is 1
2. 1 of tachogenerator (ZYS-11A 110V 2000RPM is installed on high speed shaft)
3. drg and limit switch, overspeed switch (high rotating speed) etc.
4. control housing is 1
5. resistor is 1
The master of quenching crane plays mechanism and is comprised of separate excitation power-absorption unit and stator pressure regulating speed adjusting device.Lifting mechanism is divided into two kinds of mode of operations, and a kind of is normal mode of operation, and a kind of is quencher's operation mode.Under normal mode of operation, the rise and fall of mechanism are controlled by pressure-speed regulating device.Under quencher's operation mode, lifting mechanism rises and descends one, two, voltage regulator for motor stator drives during third gear, during the decline fourth gear, controlled by separate excitation power-absorption unit (hereinafter to be referred as quenching unit), speed reaches 200% of command speed, and the energy smooth operation, and particular content is as follows:
During rising, stator pressure regulating speed adjusting device normally moves.From zero-bit to descending one grade the time, stator pressure regulating speed adjusting device is carried out the one grade of order that descends; When the decline second gear, stator pressure regulating speed adjusting device is carried out the order of decline second gear; During the decline third gear, stator pressure regulating speed adjusting device is carried out the order of decline fourth gear; When the decline fourth gear, stator pressure regulating speed adjusting device is not worked, and descends by quenching unit driving work; When the decline fourth gear was got back to each grade of decline and zero-bit, stator pressure regulating speed adjusting device was not all worked.
When first three shelves that descend arrived the decline fourth gear, the output of stator pressure regulating speed adjusting device was blocked immediately, stator pressure regulating speed adjusting device major loop no current, and output relay disconnects immediately, and stator pressure regulating speed adjusting device is not worked.Cui Huo Installed puts by getting after the contactless switch adhesive electric, obtains the instruction of quenching, and can reduce the resistance braking electric current, until satisfy the goal pace that its inner PID regulates.
To the quenching unit transition period, the motor rotor frequency feedback is normal to be connected at stator pressure regulating speed adjusting device, but the stator pressure regulating speed adjusting device mouth is not exported on request.
After master controller returns zero-bit, descend 1,2,3 grades through again shifting onto in 2 seconds, stator pressure regulating speed adjusting device is resumed work.
The above; it is only the better specific embodiment of the utility model; but protection domain of the present utility model is not limited to this; anyly be familiar with those skilled in the art in the technical scope that the utility model discloses; be equal to replacement or changed according to the technical solution of the utility model and inventive concept thereof, within all should being encompassed in protection domain of the present utility model.
Claims (1)
1. a stator pressure regulating speed adjusting device is applied to the electric control system of quenching crane, it is characterized in that, comprise separate excitation power-absorption unit and stator pressure regulating speed adjusting device, the input end of stator pressure regulating speed adjusting device is connected with power supply, the mouth of stator pressure regulating speed adjusting device is connected with contactless switch KM1, the input end of separate excitation power-absorption unit is connected with two main contacts of contactless switch KM31, the mouth of separate excitation power-absorption unit is connected with 1 master control point of contactless switch KM31, contactless switch KM1, contactless switch KM2, be connected with the stator side of motor after contactless switch KM31 parallel connection, the rotor-side of motor connects at least one group of current limliting network, described current limliting network is composed in parallel by resistance and contactless switch, last group current limiting net directly seals in resistance, wherein, contactless switch KM1 and contactless switch KM2 are with mechanical interlocked forward and reverse contactless switch, when normal mode of operation, the rising of hoist mechanism and decline are controlled by pressure-speed regulating device, when quencher's operation mode, when hoist mechanism drops to predetermined gear, controlled by stator pressure regulating speed adjusting device and be converted to the control of separate excitation engine installation, in the transition period, the motor rotor frequency feedback is normal to be connected, and the mouth of stator pressure regulating speed adjusting device is not exported.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 201220661029 CN203006774U (en) | 2012-12-04 | 2012-12-04 | Electrical control system of quenching crane applying stator variable voltage variable speed device |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 201220661029 CN203006774U (en) | 2012-12-04 | 2012-12-04 | Electrical control system of quenching crane applying stator variable voltage variable speed device |
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| Publication Number | Publication Date |
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| CN203006774U true CN203006774U (en) | 2013-06-19 |
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| Application Number | Title | Priority Date | Filing Date |
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| CN 201220661029 Expired - Fee Related CN203006774U (en) | 2012-12-04 | 2012-12-04 | Electrical control system of quenching crane applying stator variable voltage variable speed device |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105438992A (en) * | 2016-01-11 | 2016-03-30 | 辽宁国远电子有限公司 | Electrical control system and method for crane |
-
2012
- 2012-12-04 CN CN 201220661029 patent/CN203006774U/en not_active Expired - Fee Related
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105438992A (en) * | 2016-01-11 | 2016-03-30 | 辽宁国远电子有限公司 | Electrical control system and method for crane |
| CN105438992B (en) * | 2016-01-11 | 2017-05-31 | 辽宁奥达讯科科技有限公司 | Electrical control system and method for crane |
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|---|---|---|---|
| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant | ||
| CF01 | Termination of patent right due to non-payment of annual fee |
Granted publication date: 20130619 Termination date: 20191204 |
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| CF01 | Termination of patent right due to non-payment of annual fee |