Summary of the invention
The objective of the invention is to, a kind of Based Intelligent Control contactor of feedback with voltage is provided, this contactor can improve AC3 electric life and mechanical endurance, energy-conservation, reliably working and realize the miniaturization of contactor operation electromagnet.
In order to realize above-mentioned task, the present invention takes following technical scheme:
A kind of A.C. contactor of feedback intelligent control with voltage, it is characterized in that, this A.C. contactor has at least coil manipulation module, central control module, voltage detection module, power module and IGBT to drive and protection module, contains the chopper circuit that filtering, rectification circuit and power electronic device IGBT constitute in the coil manipulation module wherein;
The coil manipulation module drives with central control module, IGBT respectively and is connected with protection module, power module is connected with central control module, voltage detection module respectively, voltage detection module also is connected with central control module, described power module provides+5V and+12V two-way power supply, + 5V is as the working power of central control module, and+12V is as the voltage detection module working power;
The coil manipulation module becomes direct voltage with AC power frequency supply through input filtering and rectification; the chopper circuit of this direct voltage by forming by power electronic device IGBT; adjustable dc voltage is added on contactor coil; the voltage detection module that is provided with on the contactor coil is sampled to the direct voltage of coil; voltage signal feedback after the sampling inputs in the central control module; drive and the control wave of protection module by central control module control IGBT with power output electronic device IGBT; and regulate the duty ratio of chopper circuit automatically so that when extraneous mains fluctuations, the voltage of hold-in winding is stabilized in certain numerical value.
The A.C. contactor of feedback intelligent control with voltage of the present invention has following technical characterstic:
1. the Voltage Feedback by contactor coil, making the pull characteristics of operating electromagnet reach desirable with spring load characteristic cooperates, by reducing normal running conditions lower electromagnet moving part kinetic energy, iron coring vibration when reducing or eliminating the collision unshakable in one's determination of contact bounce when dynamic/static contact collides and sound, increase substantially the electrical endurance of contactor under the AC3 condition of work, the mechanical endurance of improving contactor simultaneously.
2. after contactor operation electromagnet sucts, utilize electromagnet sucting the very big characteristics of position electromagnetic attraction allowance, system adjusts the voltage regulation circuit of chopping duty ratio automatically, and coil power supply voltage is reduced, and saves energy.In addition since electromagnet by rectification after direct current supply, thereby the power consumption that can omit the required divided magnetic ring of general alternating electromagnet and cause by divided magnetic ring, in the electromagnetic actuation position, divided magnetic ring accounts for the very big proportion of electromagnet power consumption.
3. by the A.C. contactor of central control module control, it sucts with release voltage and is set by software programming, thereby when supply voltage drops to these two threshold values, the iron core jitter phenomenon that traditional contactor produces can not take place, and improved the contactor functional reliability.
4. by the A.C. contactor of central control module control, can allow the operation electromagnet that certain time-delay is set when discharging by software programming, to improve the ability to bear that descends suddenly in the short time when supply voltage, general contactor can make the electric equipment outage of contactor control and has an accident when running into instantaneous supply voltage rapid drawdown.
Embodiment
1. Based Intelligent Control principle:
By the regulation of GB GB14048.4-93, A.C. contactor operation electromagnet should reliable adhesive under 85% rated voltage, and general factory all designs the pick-up voltage of electromagnet in 65%~75% rated voltage for guaranteeing that contactor can reliably working under low-voltage.If the corresponding electromagnet suction characteristic F that sucts voltage
Suct=f (δ) and spring load characteristic F
f=f (δ) cooperates as shown in Figure 2, then when operating electromagnet under rated voltage during operate as normal, its pull characteristics F
Specified=f (δ) is far above spring load characteristic, under the rated voltage in the attracting process kinetic energy of moving part too big, and cause the contact vibration.
If can be by the voltage-regulating system of a band feedback, under 85%~110% rated voltage fluctuation of GB regulation, it be constant to keep in touch the device coil voltage, and makes the pull characteristics F of correspondence
IntelligenceThe only a little higher than spring load characteristic of=f (δ) then can significantly reduce the kinetic energy of normal working voltage lower electromagnet moving part, reduces or eliminates the contact vibration, and increase substantially electric life.From the pull characteristics of electromagnet as can be known, suction reduces along with working gas gap and increases very large fast, utilize electromagnet sucting the very big characteristics of position electromagnetic attraction nargin, can allow the coil voltage that sucts the position reduce and keep low-voltage, can reach purpose of energy saving by voltage regulator.The variation of A.C. contactor coil voltage in attracting process of the feedback intelligent control with voltage that the present invention proposes at attracting process, by the feedback voltage-regulating system, when change of external conditions, keeps U as shown in Figure 3
IntelligenceConstant, after moving adhesive unshakable in one's determination, coil power supply voltage reduces, and remains on U
KeepWith energy-conservation.
Owing to use a large amount of power electronic equipments on the current electrical network, thereby various power quality problems can take place.Wherein modal is voltage collapse in the short time, and it can cause contactor to discharge, and makes Be Controlled electric equipment dead electricity and have an accident.Thereby design a kind of contactor that can bear the short time voltage rapid drawdown, be the new requirement that power quality proposes contactor.
2. technical scheme
Referring to Fig. 4; the A.C. contactor of feedback intelligent control with voltage of the present invention has at least coil manipulation module, central control module, voltage detection module, power module and IGBT to drive and protection module, contains the chopper circuit that filtering, rectification circuit and power electronic device IGBT constitute in the coil manipulation module wherein.;
The coil manipulation module drives with central control module, IGBT respectively and is connected with protection module, power module is connected with central control module, voltage detection module respectively, voltage detection module also is connected with central control module, described power module provides+5V and+12V two-way power supply, + 5V is as the working power of central control module, and+12V is as the voltage detection module working power;
The coil manipulation module becomes direct voltage with AC power frequency supply through input filtering and rectification; the chopper circuit of this direct voltage by forming by power electronic device IGBT; adjustable dc voltage is added on coil; the voltage detection module that is provided with on the coil is sampled to the direct voltage of coil; voltage signal feedback after the sampling inputs in the central control module; drive and the control wave of protection module by central control module control IGBT with output electronic device IGBT; automatically regulate the duty ratio of chopper circuit so that when extraneous mains fluctuations, the voltage of hold-in winding is stabilized in certain numerical value.
The contactor that China uses at present is generally electromagnet coil and adopts interchange control, because suction is pulsed, must install divided magnetic ring additional to weaken iron coring vibration on magnetic system.Thereby the higher power loss of divided magnetic ring is to exchange the problem that control exists with iron coring vibration.And come can eliminate above shortcoming to contactor coil power supply by AC rectification being become direct current, and be easy to be conditioned by corresponding chopper circuit direct voltage, thereby the A.C. contactor of the feedback intelligent control with voltage of the present invention's proposition on this basis, purpose is the voltage of control contactor coil, makes its pull characteristics energy and spring load characteristic good fit.Its operation electromagnet coil provides energy by impulse commutation voltage, by the parameter that feedback network detected, and can be according to cooperating best pull characteristics curve to come real-time regulated coil electrical quantity with spring load characteristic.The coil power supply loop is that direct current is powered to contactor coil by chopper circuit subsequently with AC rectification, simultaneously by the feedback signal of single-chip microcomputer reception from voltage detection module, and adjust the width of output control pulse according to feedback signal, when mains ripple, keep coil voltage as shown in Figure 3.
2.1 hardware circuit design
2.1.1 hardware circuit design
The A.C. contactor of feedback intelligent control with voltage of the present invention, its operation principle is: AC power frequency 220V power supply becomes dc pulse moving voltage after input filtering and rectification, this voltage is added on the contactor operating coil by electronic power switch device IGBT.Central control module is responsible for receiving the voltage signal that voltage detection module sends, with this voltage signal serves as according to the duty ratio of determining output control pulse, the corresponding relation of voltage and control impuls duty ratio is obtained by emulation or experiment, the break-make that control impuls is come electronic power switch device in the control coil current supply circuit by the electronic power switch drive circuit, thereby direct voltage that can real-time regulated coil two ends.After attracting process is finished, change the voltage of the duty ratio of control impuls with the regulating winding two ends, make coil under a very little direct voltage, keep in touch the device contact closure.Power module provides central control module and voltage detection module power supply.
2.1.2 each function module circuit design
2.1.2.1 coil manipulation module
The coil manipulation module comprises input filtering, rectification, IGBT and contactor coil.Rectification circuit adopts the single-phase full wave rectification, and what adopt here is the rectifier bridge module.The effect of electronic power switch IGBT is the break-make coil current, and the inverse parallel diode is realized the afterflow function on the contactor coil.
The electrical schematic diagram of coil manipulation module is as shown in Figure 5: each the element model among the figure is respectively: J1 is the input connector, connects the input of industrial frequency AC 220V power supply.C11, C1, C2 are filter capacitor.U2 is the rectifier bridge of 5A.J2 is a connector, connects the operating coil two ends.D1 is a fly-wheel diode, and purpose is to release energy passage to coil is provided when IGBT turn-offs, and selecting withstand voltage 1000V, permission maximum current here is 5A.Q1 is IGBT, in order to turn on and off wire loop, because the electric current of contactor attracting process is generally at 1~3A, the electric current in sticking stage is the mA level, consider the problem of safety allowance, selected the GT25Q101 of Toshiba, its withstand voltage 1200V, the maximum current that permission is passed through is 25A, and unit price is not high yet.D2, D3 are the TVS pipe, and that select here is 1.5KE250.
2.1.2.2 central control module
The effect of central control module is contactor operating coil voltage signal and the output power electronic switching device control wave that receiving test circuit sends, the integrated level of single-chip microcomputer is more and more higher now, antijamming capability is more and more stronger, chooses the PIC16F873 single-chip microcomputer and realizes this controlled function.
PIC16F873 single-chip microcomputer inside is integrated with 5 tunnel 8 A/D converting members, and peripheral A/D converter spare has been saved in the detection of the tentaculum operating coil voltage and current signal that can achieve a butt joint, and makes antijamming capability strengthen.The work clock of the built-in pulse width modulation module of single-chip microcomputer is provided by the timer that the PIC16F873 chip integration becomes, in the output pulse width modulation waveform, single-chip microcomputer can be carried out other task, and this has just guaranteed can detect the voltage of contactor operating coil in real time and finish other function in contactor sticking stage single-chip microcomputer output burst pulse.Its specific implementation circuit is referring to Fig. 6: the physical circuit among the figure comprises single-chip microcomputer and clock circuit and reset circuit.What clock circuit adopted is passive crystal oscillator, and size is taken as 4M, and electric capacity is taken as 15pf.The MCLR/VPP pin of PIC16F873 is that low level resets, and in the experimental implementation of reality, this pin is directly connect+5 volts.D5 is an indicator light.
2.1.2.3 voltage detection module
Voltage detection module adopts amplifier to realize.The dc pulse moving voltage that rectifier gets at first passes through voltage sample, obtain the manageable voltage signal of single-chip microcomputer, import one-chip machine port through the proportioner that constitutes by amplifier again, after the computing of the built-in A/D module samples of single-chip microcomputer, obtain the mean value of pulsating voltage, thus can determine the electronic power switch control impuls the duty ratio voltage detection module block diagram as shown in Figure 7.The voltage detecting circuit circuit diagram is shown in 8.
2.1.2.4 power module
Intelligent control unit needs the two-way power supply, and+5V is as the working power of single-chip microcomputer, and+12V is as the working power of operational amplifier in the voltage and current detection circuit, and this power module can obtain stable+12 volt output when exchanging 85 volts~265 volts inputs.Adjusting through 7805 can obtain+5 volts of power supplys.Its circuit diagram as shown in Figure 9.Wherein J1 connects and exchanges 220 volts of power supplys.
2.1.2.5 IGBT drives and protection module
Referring to Figure 10, GT25Q101 gets final product conducting when applying voltage about 7V between the grid source electrode, therefore utilize optocoupler to realize the driving of IGBT.Optocoupler is selected TLP521-1 for use, and when one-chip machine port RC2 output high level, the light-emitting diode conducting is added between IGBT grid source electrode thereby drive triode conducting voltage V12, drives the IGBT conducting.The effect of R1 is to reduce parasitic oscillation.D2, D3 are the TVS pipe of 1.5ke250, and in order to absorb the energy of shutdown moment, adopting two polyphones is in order to improve absorbed power.
2.2 intelligent control unit software design
Referring to Figure 11, this figure is control unit program frame figure, when single-chip microcomputer during at executive program, at first need the direct voltage after the rectification is detected, check in the duty ratio of output control pulse then by form by emulation or experiment gained, the direct voltage of output pulse after to rectification modulated the pick-up voltage as the contactor operating coil, after time-delay a period of time sticking is finished, detect voltage again and determine the duty ratio of sticking output control pulse in the stage, regularly detect the supply power voltage of contactor operating coil at set intervals, to upgrade the output duty of ratio.Contactor suct with release voltage according to national Specification, in software, set, behind the contactor coil power turn-on, if detect obtain voltage greater than stipulating to such an extent that suct voltage and then determine duty ratio, output control pulse makes the IGBT conducting, when being in, contactor sucts the position, if detect supply voltage be lower than stipulate release voltage, then stop to export pulse, block IGBT and make the contactor coil outage.Because of the present invention sucting with release voltage realize by opening or block IGBT according to set point, thereby the phenomenon of serious shake takes place when not having traditional contactor to arrive critical value.In order to improve the ability to bear of contactor to the instantaneous voltage rapid drawdown, when supply voltage drops to release voltage, an adjustable delay is set in the mcu programming, stop the output of control impuls after the process time-delay again, and time-delay can be optional by the user.
2.3 experimental result and analysis
The present invention is energy-conservation under the enough closure conditions of assurance in the sticking stage to the purpose one that A.C. contactor carries out Based Intelligent Control, the 2nd, reduce the spring of contactor in attracting process, and improve the electric life of contactor.Therefore, the purpose of experiment is in order to verify the effect of Based Intelligent Control from these two aspects.We have measured A.C. contactor and have adopted the power consumption and the time of vibration of Based Intelligent Control front and back in the experimentation, contact and the speed of closing moment unshakable in one's determination in the A.C. contactor attracting process have also been measured, two kinds of situations are contrasted, verified the effect of Based Intelligent Control.
The A.C. contactor model that experiment is used is CJ20-160, and this contactor rated voltage is an alternating current 220V, and rated current is 160A.
2.3.1 suct the contrast of voltage, release voltage and power consumption
Can find out when sucting under the voltage situation identical from table 1 data, reduce nearly 5 times, save energy greatly with power consumption after the Electronic Control with release voltage.
Table 1 has or not contactor performance comparison under the Based Intelligent Control situation
| Based Intelligent Control is arranged | No Based Intelligent Control |
Suct voltage (V) | 151 | 151 |
Release voltage (V) | 66 | 66 |
Power consumption (W) | 7 | 34 |
2.3.2 have or not the comparison of contact time of vibration under the Based Intelligent Control situation
The contact time of vibration can reflect the mechanical endurance and the electric life of contactor intuitively in the contactor attracting process, and the contact time of vibration is long more, and the life-span of contact is short more.In order to reflect the vibration situation of contact, following method of measurement has been adopted in experiment: a direct current power supply is added on the probe of contactor two ends by resistance, the vibration situation that takes place in the process of probe of contactor closure reflects by the voltage at resistance two ends, thereby we can catch the vibration situation that the voltage of resistance is understood contact in the attracting process, and experimental principle figure as shown in figure 12.
The operation electromagnet of GB regulation contactor should be finished adhesive under 85%~110% rated voltage, therefore the time of vibration that the voltage that covers this scope relatively has or not contact under the Based Intelligent Control has been chosen in experiment, and time of vibration is measured and got its mean value 5 times under every group of voltage.Wherein the time of vibration of contact contrasts as shown in figure 13 under the 220v input voltage situation.Have or not under the Based Intelligent Control situation time of vibration more as shown in table 2.
Table 2 has or not contact time of vibration contrast under the situation of Based Intelligent Control
Input ac voltage (V) | Contact time of vibration (ms) under the no Based Intelligent Control situation | Contact time of vibration (ms) under the Based Intelligent Control situation is arranged |
150 | 1.884 | 1.022 |
160 | 3.004 | 1.128 |
170 | 3.06 | 1.150 |
180 | 3.972 | 0.88 |
190 | 3.336 | 1.356 |
200 | 3.66 | 1.049 |
210 | 3.672 | 1.344 |
220 | 5.944 | 1.048 |
230 | 4.232 | 0.912 |
242 | 6.256 | 1.224 |
Have or not trend that contact time of vibration under the Based Intelligent Control situation changes with the variation of input voltage as shown in figure 14.For showing that conveniently, abscissa is the 1ms/ lattice among the situation vibrational waveform figure of no Based Intelligent Control, have that abscissa is the 0.5ms/ lattice among the situation vibrational waveform figure of Based Intelligent Control.Can know from the oscillogram of Figure 13 and find out that vibration takes place twice in the electromagnetic actuation process, when once being the dynamic/static contact contact, when another time is sound contact unshakable in one's determination, after once contact vibration bring by iron coring vibration.Can find out significantly that by Figure 14 along with the increase of input voltage, contact closure time of vibration constantly increases gradually under the situation of no Based Intelligent Control, and after adopting Based Intelligent Control, contact closure time of vibration constantly remains at low stable degree.When at rated voltage 220V, the contact closure time of vibration constantly after the employing Based Intelligent Control is compared with no Based Intelligent Control, has reduced about 80%.
In sum, the A.C. contactor of feedback intelligent control with voltage of the present invention, after the contactor attracting process is finished, change the duty ratio of control impuls, make the actuating magnet coil under a low direct voltage, keep the magnetic system adhesive, add that DC control does not have the divided magnetic ring loss of alternating electromagnet, can reach purpose of energy saving.Since energy-conservation, the miniaturization of contactor actuating magnet also promoted.Simultaneously because the adhesive and the release voltage of contactor are controlled by microprocessor as threshold value, thereby do not have traditional contactor when supply voltage during near adhesive and releasing value electromagnet the phenomenon of seriously shaking takes place.The present invention when voltage drops to release voltage, is provided with a short time delay by mcu programming, improves the ability to bear of contactor to the supply voltage rapid drawdown.The intelligence control system model machine of making is used to control traditional CJ20-160A contactor, under the rated voltage condition, can make the contact time of vibration be reduced to 1.048ms by 5.944ms, and coil power dissipation is reduced to 7W by 34W.