CN203368375U - Motor grading frequency conversion heavy duty soft starting and harmonic wave filtering integrated apparatus - Google Patents
Motor grading frequency conversion heavy duty soft starting and harmonic wave filtering integrated apparatus Download PDFInfo
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- CN203368375U CN203368375U CN2013204049605U CN201320404960U CN203368375U CN 203368375 U CN203368375 U CN 203368375U CN 2013204049605 U CN2013204049605 U CN 2013204049605U CN 201320404960 U CN201320404960 U CN 201320404960U CN 203368375 U CN203368375 U CN 203368375U
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Abstract
The utility model provides a motor grading frequency conversion heavy duty soft starting and harmonic wave filtering integrated apparatus. The apparatus is composed of an intelligent electric energy detection module (4), a controller (7), a grading frequency conversion soft starting subsystem and a harmonic wave filtering subsystem. The grading frequency conversion soft starting subsystem is connected with the stator end of a motor; the harmonic wave filtering subsystem is connected with the wire inlet end of the first variable reactor in the grading frequency conversion soft starting subsystem; and the controller (7) is respectively connected with the intelligent electric energy detection module (4), and the thyristor circuits of the two subsystems through a data line. By using the apparatus provided by the utility model, the functions of grading frequency conversion soft starting and harmonic wave filtering can be simultaneously realized so that not only can the requirements of a high-voltage large-power motor for starting current and a starting torque be met, and harmonic wave filtering can also be realized when the motor is started, the starting performance of the motor is improved, energy is saved, consumption is reduced, the voltage of an electrical network is ensured to be stable, and the cost performance is high, therefore, the provided apparatus id suitable for the heavy duty soft starting of the high-voltage large-power motor.
Description
Technical field
The utility model relates to grading variable-frequency soft starting and the harmonic field of motor, particularly relates to a kind of motor classification frequency conversion soft start under heavy load and harmonic integrated apparatus.
Background technology
Along with scientific and technical develop rapidly, intelligent control system is widely used, and simultaneously this has also proposed a lot of requirements to people, and as supporting as the intelligence of the fluctuation of electrical network, actuator etc., its requirement is all more and more stricter.As the motor of important driving actuator, should lay good basis for Based Intelligent Control, while reducing motor starting again to the impact of electrical network.So the starting link of motor is the part that people should attract great attention.
The starting of motor generally has three kinds of methods: across-the-line starting, reduced voltage starting and varying frequency starting.Although across-the-line starting is simple and convenient, but in across-the-line starting, starting current very large (being about 5-7 times of above motor rated current), and starting torque is very low again, very large of this impact on load and equipment, thereby require high or occasion high-power all to be not suitable for selecting the mode of across-the-line starting in control precision.Traditional reduced voltage starting is normally keeping under the prerequisite that starting frequency is constant gradually the lifting motor terminal voltage until the mode of rated voltage is carried out starting motor, as auto-transformer starting, magnet controlled soft start etc.But most of traditional reduced voltage starting mode voltage-regulation scopes are smaller, and cranking current pulse is larger, and starting torque is very low, can't meet the requirement of heavy-load start.
Based on this, varying frequency starting, due in the process of starting motor, has not only changed the terminal voltage of motor, has also changed the frequency of voltage, thereby make, its starting current is less, starting torque is very large, has fully made up the multiple weak point in traditional reduced voltage starting.But, because general frequency converter price comparison is high, especially in the occasion of high voltage control, price with respect to the high voltage converter of high-tension motor is very expensive especially, and that the control mode of varying frequency starting technology is complicated, reliability compares is poor, thereby be not widely used in actual applications.
Along with the developing rapidly and using of various power electronic equipments, the harmonic pollution of electrical network is on the rise, and the various faults that caused by harmonic wave and accident also constantly occur.If the harmonic wave content that power electronic equipment produces in the process of transformation of electrical energy is excessive, not only can produce harm to the Stability and dependability of system, also can cause power consumption equipment (as motor, the communication equipment etc.) job insecurity in system, thereby cause the impacts such as equipment fault, job insecurity, will threaten the safety of equipment and the person when serious.
Applicant had before been invented " a kind of variable reactor (200610019026.6) ", " a kind of soft starter device of motor (200620096602.2) ", " the classification frequency conversion soft start under heavy load device (201020590402.9) based on variable reactor " etc.Wherein: patent " a kind of variable reactor " relates generally to the reactor that a kind of resistance value can stepless change, mainly by winding and secondary winding, formed, by the secondary winding side is applied to control, just can regulate the resistance value on winding one time without polar region, for realizing the intelligent condition of having created of controlling.Patent " a kind of soft starter device of motor " is serially connected in the first side winding of variable reactor in the major loop of motor, indirectly regulate the impedance on the variable reactor first side winding by thyristor control variable reactor secondary side, then regulate the dividing potential drop on the variable reactor first side winding, reach the effect of controlling terminal voltage of motor, finally realize the purpose of the starting current of restrictions motor.Patent " the classification frequency conversion soft start under heavy load device based on variable reactor " combines the variable reactor technology with the grading variable-frequency soft starting technology of motor, utilize the components and parts such as variable reactor and thyristor circuit to realize the grading variable-frequency soft starting of motor, but the harmonic wave that this device produces in filtering classification conversion process in actual applications well, so its harmonic content is larger, be unfavorable for the safety and stablization of motor.
Patent " a kind of soft starter device of motor " provides the function of the starting current limliting of motor, but well do not solve the too little problem of the torque value of motor in starting process, can not realize the heavy-load start of motor, be subject in actual applications many restrictions.And patent " the classification frequency conversion soft start under heavy load device based on variable reactor " is although solved the problem of starting current limliting with large torque starting, but do not carry out filtering for the power supply after the classification frequency conversion, cause harmonic content larger, this can cause motor starting not steady, many adverse consequencess such as torque, electric current, mains ripple are larger.
Summary of the invention
Technical problem to be solved in the utility model is: for the not enough problem of existing motor starting method, a kind of motor classification frequency conversion soft start under heavy load and harmonic integrated apparatus are provided, this device can be realized motor, and when starting, starting steadily, starting current is little, starting torque is large, and the main harmonic wave in effective filter out power.
The technical scheme that the utility model solves its technical problem employing is: intelligent electric energy detection module, controller, grading variable-frequency soft starting subsystem and harmonic subsystem, consist of, wherein the grading variable-frequency soft starting subsystem is connected with the stator terminal of motor, the harmonic subsystem is connected with the end of incoming cables of the first variable reactor in the grading variable-frequency soft starting subsystem, and controller is connected with the thyristor circuit in described two subsystems with intelligent electric energy detection module respectively by data wire.
Described grading variable-frequency soft starting subsystem, can mainly by the first variable reactor, the first thyristor circuit, voltage current transformer, starting contactor, be formed, wherein: after the first side winding of the first variable reactor is connected in the mode of connecting with the power inleting terminal of motor, by starting contactor, voltage current transformer, primary cut-out and high voltage isolator access electrical network, the secondary side winding of the first variable reactor is connected with the first thyristor circuit.
Described harmonic subsystem, can mainly by the second variable reactor, the second thyristor circuit, tunable capacitor group, contactor, be formed, wherein: the first side winding of the second variable reactor, the one end is connected with the ungrounded end of tunable capacitor group, and the other end is connected with the end of incoming cables of the first side winding of the first variable reactor by contactor; The secondary side winding of the second variable reactor is connected with the second thyristor circuit.
Described tunable capacitor group can be formed after in parallel with the series circuit of a plurality of capacitors by many groups fast acting fuse, a plurality of capacitor switching contactor.
It is core parts that described controller can adopt microprocessor, coordinate peripherally detect, communication, storage, input the circuit such as output, AD the DA conversion wait circuit, optimum division, the starting process logic that can realize frequency division interval in preferred harmonic compensation calculating, motor starting procedure switched, the break-make of contactor is controlled, the functions such as output of thyristor triggering impulse, guaranteed the co-ordination of classification frequency conversion and harmonic function.
The utility model is compared with existing motor starting system, has the following advantages:
Motor classification frequency conversion soft start under heavy load and harmonic integrated apparatus that the utility model provides, integrate " grading variable-frequency soft starting and harmonic " function, met the requirement of high voltage and high power electromotor for starting current and starting torque, also when motor starting, realize harmonic, improved better on the whole the starting performance of motor, energy-saving and cost-reducing, keep Network Voltage Stability.Specific as follows:
(1) the grading variable-frequency soft starting subsystem is realized the grading variable-frequency soft starting of motor; reduce the maximum starting current (be about rated value 2 times) of motor and increase its starting torque; meet the soft start under heavy load of motor, protected motor and driven equipment thereof.
(2) the harmonic subsystem is realized harmonic wave control, can be according to actual harmonic value in the starting process of motor, the parameter of dynamic adjustments filter, make filter constantly can keep resonance and reach good filter effect, reduce the impact to electrical network, kept pressure drop of grid lower than 5%.
(3) controller can realize that preferred harmonic compensates the functions such as the optimum division in frequency division interval in calculating, motor starting procedure, the switching of starting process logic, has guaranteed the co-ordination of classification frequency conversion and harmonic function, makes system works in optimum state.
The accompanying drawing explanation
Fig. 1 is the schematic diagram of a kind of motor classification of the utility model frequency conversion soft start under heavy load and harmonic integrated apparatus.
In figure: 1. high voltage isolator; 2. primary cut-out; 3. voltage current transformer; 4. intelligent electric energy detection module; 5. the first variable reactor; 6. the first thyristor circuit; 7. controller; 8. the second thyristor circuit; 9. tunable capacitor group; 10. the second variable reactor.
Embodiment
Motor classification frequency conversion soft start under heavy load and harmonic integrated apparatus that the utility model provides, by motor grading variable-frequency soft starting subsystem and harmonic subsystem, comprehensively formed, it is in conjunction with the variable reactor technology, adopt the mode of grading variable-frequency soft starting to start heavily loaded motor, the harmonic wave simultaneously voltage after the classification frequency conversion produced carries out dynamic harmonic filtering, not only solved the motor starting electric current too high, the problem that starting torque is too little, realized that motor starting when starting is steady, starting current is little, starting torque is large, also filtering the harmful harmonic wave in the power supply, better protected motor.
Below in conjunction with embodiment and accompanying drawing, the utility model is described in further detail, but be not limited to following described content.
Motor classification frequency conversion soft start under heavy load and harmonic integrated apparatus that the utility model provides, its structure chart as shown in Figure 1, by grading variable-frequency soft starting subsystem and harmonic subsystem, formed, wherein: the grading variable-frequency soft starting subsystem mainly consists of the first variable reactor 5 and the first thyristor circuit 6, and the harmonic subsystem mainly consists of with tunable capacitor group 9 the second variable reactor 10, the second thyristor circuit 8.The grading variable-frequency soft starting subsystem is connected with the stator terminal of motor, and the harmonic subsystem is connected in the end of incoming cables of the first variable reactor 5.Control the break-make of thyristors by controller 7, realize the function of grading variable-frequency soft starting and the harmonic of motor, make motor steadily, safety, effectively start and the most of harmonic wave in filtering appts.
Described grading variable-frequency soft starting subsystem also comprises controller 7, voltage current transformer 3, intelligent electric energy detection module 4, contactor KM1 and contactor KM2.Wherein the first side winding of the first variable reactor 5 is connected and accesses electrical network by starting contactor KM1, voltage current transformer 3, primary cut-out 2 and high voltage isolator 1 afterwards in the mode of connecting with the power inleting terminal of motor, and the secondary side winding of the first variable reactor 5 is connected with the first thyristor circuit 6.Intelligence electric energy detection module 4 gathers the signal that voltage current transformer 3 sends, and by data wire, with controller 7, is connected, and the thyristor triggering impulse signal that controller 7 sends is connected with the first thyristor circuit by data wire.The two ends of contactor KM2 are connected to the end of incoming cables of contactor KM1 and the leading-out terminal of the first variable reactor.
The course of work of described grading variable-frequency soft starting subsystem is: controller 7 is by the voltage in the electric electromechanics source signal that receives intelligent electric energy detection module 4 collections, electric current and frequency values, according to predefined algorithm, by controlling output pulse signal, regulate the break-make of the thyristor in the first thyristor circuit 6, change electric current and the frequency values in the primary side loop of the first variable reactor 5, the size of the voltage on the dynamic adjustments motor and frequency, the voltage and the frequency that make to be added on motor are had the variation of the utmost point by the constant voltage and frequency ratio of setting, thereby realize the purpose of motor grading variable-frequency soft starting, can realize the little electric current of motor, large torque starting, especially be applicable to the heavy-load start of high voltage and high power electromotor.When motor carries out grading variable-frequency soft starting, control and output to voltage and the frequency values on motor by controller 7, make the frequency values on motor polar region be arranged gradually from f
nincrease to f
1, finally reach rated value f
0, its magnitude of voltage is also changed according to constant voltage and frequency ratio with the change of frequency values.The voltage waveform be added on motor should suddenly change continuously and not, and the size of the frequency when duration of each grade of frequency division will be according to different frequency division is carried out analytical calculation in advance, and the voltage be about to after n level frequency division is controlled at times, and t
n, t
n-1..., t
2, t
1size by controller 7, regulated.
Described harmonic subsystem also comprises the second variable reactor 10, the second thyristor circuit 8, tunable capacitor group 9, controller 7, voltage current transformer 3, intelligent electric energy detection module 4 and contactor KM3.The first side winding of the second variable reactor 10 wherein, the one end is connected with the ungrounded end of tunable capacitor group 9, and its other end is connected with the end of incoming cables of the first side winding of the first variable reactor 5 with KM1 by contactor KM3; The secondary side winding of the second variable reactor 10 is connected with the second thyristor circuit 8, the angle of flow of the thyristor of controller 7 by controlling the second thyristor circuit 8 is regulated the size of the reactance value L in access harmonic subsystem, and the size of regulating the capacitance C of access harmonic subsystem by the break-make of controlling each contactor in tunable capacitor group 9, under harmonic frequency f, form a low-impedance path to absorb harmonic wave.Many group fast acting fuse (FU1, FU2, FUn), capacitor switching contactor (KM11, KM12, KM1n) with capacitor (C1, C2 ... Cn) series circuit forms tunable capacitor group 9 after parallel connection, one end of common port in parallel is connected with the first side winding of the second variable reactor 10, other end ground connection.
The Dynamic Regulating Process of described harmonic subsystem is: the electric power signal such as the voltage that intelligent electric energy detection module 4 detections are sent by voltage current transformer 3, electric current, harmonic wave, and send controller 7 to, controller 7 is determined number of times and the size of main harmonic wave by computational analysis, according to the principle of LC passive filtering, calculate optimal capacitance value and the inductance value of filter.Its concrete mode is: at first, by calculating best condenser capacity, the make and break of control contactor KM11～KM1n drops into the capacitor of tunable capacitor group 9, regulates the capacitance of the reality of access harmonic subsystem; Then, on the basis of this capacitance, calculate best inductance value by controller 7, and control and export the thyristor triggering impulse signal, regulate the angle of flow of thyristor in the second thyristor circuit 8, regulate the reactance value of the primary side of the second variable reactor 10, realize effective filtering of the harmonic wave in the grading variable-frequency soft starting process.
After the motor grading variable-frequency soft starting finishes, by controller 7, the switching of control contactor (disconnects contactor KM1, closed contactor KM2 of while), excision grading variable-frequency soft starting subsystem, and the harmonic subsystem works on, and realizes the harmonic wave control of electrical network.
It is core parts that described controller 7 adopts microprocessor, coordinate peripherally detect, communication, storage, input the circuit such as output, the devices such as AD/DA conversion, optimum division, the starting process logic that can realize frequency division interval in preferred harmonic compensation calculating, motor starting procedure switched, the break-make of contactor is controlled, the functions such as output of thyristor triggering impulse, guaranteed the co-ordination of classification frequency conversion and harmonic function.
The total course of work of the motor classification frequency conversion soft start under heavy load that the utility model provides and harmonic integrated apparatus is as follows:
1. closing by hand QS(high voltage isolator 1), QF(primary cut-out 2), after the intelligent electric energy detection module 4 in circuit and controller 7 access power supplys electric, controller 7 is started working;
2. pass through controller 7 by contactor KM1, KM3 closure, now the first side winding of the first variable reactor 5 accesses electrical network with motor by the mode of connecting, and the grading variable-frequency soft starting subsystem puts into operation; The first side winding of the second variable reactor 10 accesses the end of incoming cables of the first side winding of the first variable reactor 5 after connecting with tunable capacitor group 9, the harmonic subsystem puts into operation;
3. according to predefined algorithm, by controller 7 output pulse signals, control the break-make of the thyristor in the first thyristor circuit 6, thereby realize the grading variable-frequency soft starting of motor;
4. from motor carries out grading variable-frequency soft starting, the harmonic signal that controller 7 produces by analysis circuit, control contactor KM11～KM1n closing or opening, thereby optimal capacitance is accessed to electrical network; Export other pulse signal simultaneously, control the break-make angle of the thyristor of the second thyristor circuit 8, regulate the best inductance value of the first side winding of the second variable reactor 10, under harmonic frequency f, form a low-impedance path to absorb harmonic wave;
5. after motor starting procedure finishes, disconnect contactor KM1, closed contactor KM2, excision grading variable-frequency soft starting subsystem, the grading variable-frequency soft starting process finishes, and motor enters the nominal operation state; The harmonic subsystem is proceeded mains by harmonics filtering simultaneously.
The utility model is the motor soft start device of a kind of collection " grading variable-frequency soft starting and harmonic " one.The report of domestic grading variable-frequency soft starting, harmonic aspect is arranged, but have no the report about the motor soft start device aspect of collection " grading variable-frequency soft starting and harmonic " one.Known through Comprehensive Comparison, motor classification frequency conversion soft start under heavy load provided by the utility model is not yet found identical or similar report in pertinent literature at home with the harmonic integrated apparatus.
Claims (4)
1. a motor classification frequency conversion soft start under heavy load and harmonic integrated apparatus, is characterized in that this device is comprised of intelligent electric energy detection module (4), controller (7), grading variable-frequency soft starting subsystem and harmonic subsystem; The grading variable-frequency soft starting subsystem is connected with the stator terminal of motor, the harmonic subsystem is connected with the end of incoming cables of the first variable reactor (5) in the grading variable-frequency soft starting subsystem, and controller (7) is connected with the thyristor circuit in two subsystems with intelligent electric energy detection module (4) respectively by data wire.
2. motor classification frequency conversion soft start under heavy load according to claim 1 and harmonic integrated apparatus, it is characterized in that described grading variable-frequency soft starting subsystem, mainly by the first variable reactor (5), the first thyristor circuit (6), voltage current transformer (3), starting contactor forms, the first side winding of the first variable reactor (5) is passed through starting contactor after being connected in the mode of connecting with the power inleting terminal of motor, voltage current transformer (3), primary cut-out (2) and high voltage isolator (1) access electrical network, the secondary side winding of the first variable reactor (5) is connected with the first thyristor circuit (6).
3. motor classification frequency conversion soft start under heavy load according to claim 1 and harmonic integrated apparatus, it is characterized in that described harmonic subsystem, mainly formed by the second variable reactor (10), the second thyristor circuit (8), tunable capacitor group (9), contactor; The first side winding of the second variable reactor (10), the one end is connected with the ungrounded end of tunable capacitor group (9), and the other end is connected with the end of incoming cables of the first side winding of the first variable reactor (5) by contactor; The secondary side winding of the second variable reactor (10) is connected with the second thyristor circuit (8).
4. motor classification frequency conversion soft start under heavy load according to claim 3 and harmonic integrated apparatus, it is characterized in that: described tunable capacitor group (9) is formed with the series circuit of a plurality of capacitors by many groups fast acting fuse, a plurality of capacitor switching contactor after in parallel.
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| CN2013204049605U CN203368375U (en) | 2013-07-08 | 2013-07-08 | Motor grading frequency conversion heavy duty soft starting and harmonic wave filtering integrated apparatus |
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| CN2013204049605U CN203368375U (en) | 2013-07-08 | 2013-07-08 | Motor grading frequency conversion heavy duty soft starting and harmonic wave filtering integrated apparatus |
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2018196264A (en) * | 2017-05-18 | 2018-12-06 | アイシン精機株式会社 | Noise removal circuit |
| CN111969894A (en) * | 2020-09-21 | 2020-11-20 | 浙江星控信息技术有限公司 | Hard start, soft start, frequency conversion start integration switching module |
-
2013
- 2013-07-08 CN CN2013204049605U patent/CN203368375U/en not_active Expired - Fee Related
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2018196264A (en) * | 2017-05-18 | 2018-12-06 | アイシン精機株式会社 | Noise removal circuit |
| CN111969894A (en) * | 2020-09-21 | 2020-11-20 | 浙江星控信息技术有限公司 | Hard start, soft start, frequency conversion start integration switching module |
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| Date | Code | Title | Description |
|---|---|---|---|
| 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: 20131225 Termination date: 20140708 |
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| EXPY | Termination of patent right or utility model |