CN208722672U - A kind of walkie high-current demagnetization instrument based on Switching Power Supply - Google Patents
A kind of walkie high-current demagnetization instrument based on Switching Power Supply Download PDFInfo
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- CN208722672U CN208722672U CN201821356885.9U CN201821356885U CN208722672U CN 208722672 U CN208722672 U CN 208722672U CN 201821356885 U CN201821356885 U CN 201821356885U CN 208722672 U CN208722672 U CN 208722672U
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Abstract
A kind of walkie high-current demagnetization instrument based on Switching Power Supply, belongs to power domain, it is characterised in that: including step-down transformer, controllable rectifier module, flat wave capacitor, buck chopper module and the inverting module being sequentially connected electrically；It further include rectification drive module, Chopper driving module and single chip control module；Step-down transformer and controllable rectifier module are electrically connected with rectification drive module；Flat wave capacitor is electrically connected with Chopper driving module and single chip control module respectively；Chopper driving module is electrically connected with buck chopper module；Single chip control module is electrically connected with inverting module, Chopper driving module and rectification drive module respectively.The filter inductance in Buck buck circuit is replaced using load, simplify main loop design significantly and reduces the volume of demagnetization instrument；By serving as the energy storage inductor in buck circuit, lowering apparatus weight using transformer winding, while the driving circuit of demagnetization instrument described in the utility model is at low cost, and cost performance is high.
Description
Technical field
The utility model belong to power domain more particularly to it is a kind of suitable for large-capacity electrical apparatus based on Switching Power Supply
Walkie high-current demagnetize instrument.
Background technique
In power domain, power transformer and reactor complete iron core after D.C. resistance is tested and can generate remanent magnetism, work as recurrence
When into operating status, overexcitation caused by remanent magnetism may cause relevant device loss or the system failure.Traditional straight resistance instrument does not have
Standby demagnetization function only has industrial frequency AC demagnetization function, for high-power transformer, causes demagnetization speed slow.And it is general low
For frequency AC demagnetization instrument using power amplifier as power output stage, current rise rate is limited.
Summary of the invention
The utility model patent is slow in order to solve the demagnetization such as large-capacity power transformer and reactor speed, and demagnetization effectiveness is poor
The problem of, provide a kind of walkie high-current demagnetization instrument based on Switching Power Supply.
Walkie high-current demagnetization instrument described in the utility model based on Switching Power Supply, including the decompression being sequentially connected electrically
Transformer, controllable rectifier module, flat wave capacitor, buck chopper module and inverting module；It further include rectification drive module, copped wave drive
Dynamic model block and single chip control module；The step-down transformer and controllable rectifier module are electrically connected with rectification drive module；
The flat wave capacitor is electrically connected with Chopper driving module and single chip control module respectively；The Chopper driving module and decompression
Copped wave module is electrically connected；The single chip control module respectively with inverting module, Chopper driving module and rectification drive module
It is electrically connected.
Walkie high-current demagnetization instrument described in the utility model based on Switching Power Supply, the rectification drive module include
Synchronous generator, commutation controller and the silicon-controlled driving being sequentially connected electrically；The synchronous generator and aforementioned drop
Pressure transformer is electrically connected；The silicon-controlled driving is electrically connected with aforementioned controllable rectifier module.
Walkie high-current demagnetization instrument described in the utility model based on Switching Power Supply, the Chopper driving module include
Voltage and current sample circuit, feedback loop, chop control chip and the IGBT driving being sequentially connected electrically；The voltage and current sampling
Circuit is electrically connected with aforementioned flat wave capacitor；The IGBT driving is electrically connected with buck chopper module.
Walkie high-current demagnetization instrument described in the utility model based on Switching Power Supply, the single chip control module packet
Include AD sample circuit, protective module, rectified voltage DA output circuit, chopper current DA output circuit, single-chip microcontroller, commutation control mould
Block and display and key module；The display is sequentially connected electrically with key module, single-chip microcontroller and commutation control module；The AD is adopted
Sample circuit, protective module, rectified voltage DA output circuit, chopper current DA output circuit are electrically connected with single-chip microcontroller；It is described
Protective module is electrically connected with rectified voltage DA output circuit and chopper current DA output circuit respectively；The AD sample circuit point
It is not electrically connected with aforementioned flat wave capacitor and inverting module；The rectified voltage DA output circuit is mutually electric with aforementioned commutation controller
Connection；The chopper current DA output circuit is electrically connected with aforementioned chop control chip；The commutation control module with it is aforementioned
Inverting module is electrically connected.
It is described in the utility model based on Switching Power Supply walkie high-current demagnetization instrument demagnetizing method be, will subject around
Group is electrically connected with demagnetization instrument, then applies positive and negative step voltage signal to subject winding and detects remanent magnetism, and judges the pole of remanent magnetism
Property and degree, the instrument that manually carries out being demagnetized after demagnetization parameter setting demagnetize.
It is described in the utility model based on Switching Power Supply walkie high-current demagnetization instrument demagnetizing method, it is described subject around
Group applies positive and negative step voltage signal and detects remanent magnetism method are as follows: successively includes two using demagnetization instrument to subject winding output voltage
Group, a positive polarity and a negative polarity step voltage signal, while detection winding electric current；If subject winding magnetic core has remanent magnetism, just
Winding current curve under polarity and negative polarity step voltage signal, the increase in current speed ratio in remanent magnetism polarity is in remanent magnetism
Increase in current rate on opposite polarity is fast.
The demagnetizing method of walkie high-current demagnetization instrument described in the utility model based on Switching Power Supply, the demagnetization instrument
To the method for subject winding output voltage are as follows: constitute Buck buck circuit structure by main circuit, subject winding serves as filter
The effect of wave inductance, when copped wave module is connected, DC voltage is applied to transformer, on reactor winding, raising speed on electric current in circuit
Rate is directly proportional to applied voltage, is inversely proportional with winding magnetizing inductance amount.Increase the output voltage i.e. controllable current of rectification module
Climbing speed；Control the i.e. controllable current peak of turn-on time of major loop Buck switch.
The demagnetizing method of walkie high-current demagnetization instrument described in the utility model based on Switching Power Supply, the demagnetization
Process is divided into low-frequency ac demagnetization and pulsating direct current is demagnetized two kinds.
The demagnetizing method of walkie high-current demagnetization instrument described in the utility model based on Switching Power Supply, the low frequency are handed over
Flow the process of demagnetization are as follows: positive and negative step voltage signal is applied to subject winding first, judges the polarity and degree of remanent magnetism, it is then right
Peak impulse voltage amplitude, demagnetization current peak value, the current attenuation ratio of every half of cycle, pressure demagnetizing time are configured,
And calculate the half cycles number of scheduled current attenuation ratio；After accomplishing the setting up enter demagnetization phase, it is polar anti-to remanent magnetism first
To alternation is applied, then constantly commutation；Demagnetization current from peak value according to current attenuation ratio in each half cycles gradually
Decaying；After the cycle number for completing setting, remanent magnetism detection is carried out, if remanent magnetism is met the requirements, demagnetization terminates；If being unsatisfactory for wanting
It asks, then continues to demagnetize according to the degree selection peak point current of remanent magnetism.
The demagnetizing method of walkie high-current demagnetization instrument described in the utility model based on Switching Power Supply, the pulsation are straight
Flow the process of demagnetization are as follows: positive and negative step voltage signal is applied to subject winding first, judges the polarity and degree of remanent magnetism, it is then right
Peak impulse voltage, demagnetization peak point current, demagnetization valley point current and demagnetization time are configured；After accomplishing the setting up enter demagnetization rank
Section；First to the polar reversed application pulsating direct current electric current of remanent magnetism, stop after reaching the demagnetization time manually set, and automatically into
The detection of row remanent magnetism, user's selection continue pulsating direct current demagnetization or low-frequency ac demagnetization.
Walkie high-current demagnetization instrument described in the utility model based on Switching Power Supply, passes through the decompression being sequentially connected electrically
Transformer, controllable rectifier module, flat wave capacitor, buck chopper module and inverting module；It further include rectification drive module, copped wave drive
Dynamic model block and single chip control module constitute demagnetization instrument major loop, replace the filtered electrical in Buck buck circuit using load
Sense, so that main loop design significantly simplifies and reduces the volume of demagnetization instrument；It is cut by serving as decompression using transformer winding
Energy storage inductor in wave circuit, without the filter inductance of special configuration large capacity, lowering apparatus weight.Major loop is opened using IGBT
It closes device and controls on-off, reduced compared to the transformer demagnetization instruments weight using Linear Amplifers devices such as triodes.Simultaneously originally
The driving circuit of demagnetization instrument described in utility model is low in cost, and cost performance is high.
Detailed description of the invention
Fig. 1 is the walkie high-current demagnetization instrument structural schematic block diagram described in the utility model based on Switching Power Supply；
Fig. 2 is the walkie high-current demagnetization instrument main loop circuit schematic diagram described in the utility model based on Switching Power Supply.
Specific embodiment
Walkie high-current demagnetization to described in the utility model based on Switching Power Supply with reference to the accompanying drawings and embodiments
Instrument is described in detail.
Walkie high-current demagnetization instrument described in the utility model based on Switching Power Supply, as shown in Figure 1, major loop includes
Step-down transformer, controllable rectifier module, flat wave capacitor, buck chopper module and the inverting module being sequentially connected electrically；Further include by
Rectify the drive control circuit of drive module, Chopper driving module and single chip control module composition；The step-down transformer and
Controllable rectifier module is electrically connected with rectification drive module；The flat wave capacitor respectively with Chopper driving module and single-chip microcontroller control
Molding block is electrically connected；The Chopper driving module is electrically connected with buck chopper module；The single chip control module difference
It is electrically connected with inverting module, Chopper driving module and rectification drive module.The rectification drive module includes being sequentially connected electrically
Synchronous generator, commutation controller and silicon-controlled driving；The synchronous generator and aforementioned step-down transformer phase
Electrical connection；The silicon-controlled driving is electrically connected with aforementioned controllable rectifier module.The Chopper driving module includes successively being electrically connected
Voltage and current sample circuit, feedback loop, chop control chip and the IGBT driving connect；The voltage and current sample circuit is with before
Flat wave capacitor is stated to be electrically connected；The IGBT driving is electrically connected with buck chopper module.It include slope compensation in feedback loop
Function can prevent subharmonic oscillation phenomenon.
Walkie high-current demagnetization instrument described in the utility model based on Switching Power Supply, the single chip control module packet
Include AD sample circuit, protective module, rectified voltage DA output circuit, chopper current DA output circuit, single-chip microcontroller, commutation control mould
Block and display and key module；The display is sequentially connected electrically with key module, single-chip microcontroller and commutation control module；The AD is adopted
Sample circuit, protective module, rectified voltage DA output circuit, chopper current DA output circuit are electrically connected with single-chip microcontroller；It is described
Protective module is electrically connected with rectified voltage DA output circuit and chopper current DA output circuit respectively；The AD sample circuit point
It is not electrically connected with aforementioned flat wave capacitor and inverting module；The rectified voltage DA output circuit is mutually electric with aforementioned commutation controller
Connection；The chopper current DA output circuit is electrically connected with aforementioned chop control chip；The commutation control module with it is aforementioned
Inverting module is electrically connected.
The demagnetizing method of walkie high-current demagnetization instrument described in the utility model based on Switching Power Supply, will be tested winding
It is electrically connected with demagnetization instrument, positive and negative step voltage signal then is applied to subject winding and detects remanent magnetism, and judges the polarity of remanent magnetism
With degree, demagnetize after manually carrying out demagnetization parameter setting through demagnetization instrument, the process of demagnetization is divided into low-frequency ac demagnetization and arteries and veins
Dynamic two kinds of direct current demagnetization.
The demagnetizing method of walkie high-current demagnetization instrument described in the utility model based on Switching Power Supply, the detection are surplus
Magnetic method particularly includes: be mutually tested transformer winding output voltage using demagnetization instrument；The voltage include two groups, a positive polarity and
One negative polarity step voltage signal, while detecting detection winding electric current；If subject winding magnetic core has remanent magnetism, positive polarity and cathode
Winding current curve uphill process under property step voltage signal can be distinct, the increase in current speed ratio in remanent magnetism polarity
Increase in current rate on the opposite polarity of remanent magnetism is fast.Winding current curve array X under test measurement to two polarityn、
Yn, it is worth on the basis of the winding current curve array small by average value, passes through two winding current curve array each point relative errors
Average value measure winding remanent magnetism uneven degree.When the value is when within 10%, then it is assumed that demagnetization is completed, it is understood that there may be
Faint remanent magnetism has not influenced transformer and has put into operation.If the value is greater than 10%, then it is assumed that with the presence of remanent magnetism, the size of the value characterizes remanent magnetism
Degree.
In the present embodiment, as shown in Figure 1, single chip control module core devices are STM32F407 single-chip microcontroller, AD sampling
Module core device is modulus conversion chip AD7606, rectified voltage DA output module and chopper current DA output module core device
Part is analog-digital chip TLC5615, commutation control module model IR2110.Rectification drive module core is commutation controller
In TCA787 phase-shifting trigger control chip.Chopper driving module core is chop control chip TL494.
Step-down transformer voltage ratio as shown in Figure 2 is 380/220V, capacity 5kVA；Rectification module model SKDH
145/12；Flat wave capacitor model 600V/1500 μ F electrolytic capacitor；Buck switchs model SKM300GA12E4；Two pole of afterflow
Pipe model SKR 136F12；De-excitation resistance rated capacity is 30KJ；Absorption Capacitance is 1200V/3 μ F metallized film capacitor；
Continued flow switch model SKM300GA12E4；Inverting module model SEMiX251GD126HDs.
Principle of the demagnetization instrument to subject transformer winding output electric current are as follows: as shown in Fig. 2, being made up of main circuit
Buck buck circuit structure, subject winding serve as filter inductance effect, and when copped wave module is connected, DC voltage is applied to change
On depressor, reactor winding, current rise rate is directly proportional to applied voltage in circuit, is inversely proportional with winding magnetizing inductance amount,
Increase the i.e. controllable current rise rate of output voltage of rectification module；The turn-on time of control major loop Buck switch, that is, controllable
Current peak processed.
The method that demagnetization instrument generates positive and negative polarity step voltage, first setting peak impulse voltage and pulse current peak,
It is tested again.Positive polarity step voltage is generated first.The work of inverting module circuit, the first bridge arm switch and four bridge legs switch
Conducting, the second bridge arm switch and third bridge arm switch OFF.Controllable rectifier module work, adjust automatically flat wave capacitor voltage is to setting
Determine peak impulse voltage.Buck switch is transferred on state from shutdown, and pulse voltage is applied directly on test product winding at this time, arteries and veins
Electric current is rushed to be gradually increasing.After test product electric current reaches pulse current peak, Buck switch is disconnected, and test product electric current passes through two pole of afterflow
Pipe afterflow is simultaneously down to zero.
Then reversed polarity step voltage is generated.The work of inverting module circuit, the second bridge arm switch and third bridge arm switch are led
It is logical, the first bridge arm switch and four bridge legs switch OFF.Controllable rectifier module work, adjust automatically flat wave capacitor voltage to setting
Peak impulse voltage.Buck switch is transferred on state from shutdown, and pulse voltage is applied directly on test product winding at this time, pulse
Electric current is gradually increasing.After test product electric current reaches pulse current peak, Buck switch is disconnected, and test product electric current passes through freewheeling diode
Afterflow is simultaneously down to zero.
The process of low-frequency ac demagnetization are as follows: positive and negative step voltage signal is applied to subject transformer first, judges remanent magnetism
Polarity and degree, then to peak impulse voltage amplitude, demagnetization current peak value, the current attenuation ratio of every half of cycle, pressure
Demagnetizing time is configured；After accomplishing the setting up device calculates the half cycles number of scheduled current attenuation ratio automatically.Into demagnetization
Stage, first to the polar reversed application alternation of remanent magnetism.Commutate bridge arm movement, and Buck buck circuit is applied to transformer
Making alive direction adjusts reversed to transformer remanence direction.Controllable rectifier module work, adjust automatically flat wave capacitor voltage is extremely
Set peak impulse voltage.Buck switch is transferred on state from shutdown, and pulse voltage is applied directly on test product winding at this time,
Pulse current is gradually increasing.After test product electric current reaches pulse current peak, Buck switch is disconnected, and test product electric current passes through afterflow two
Pole pipe afterflow is simultaneously down to zero.
Subsequently into lower half of cycle, commutate bridge arm movement, and Buck buck circuit applies voltage direction to transformer
It adjusts in the same direction to transformer remanence direction.Controllable rectifier module work, adjust automatically flat wave capacitor voltage is to setting pulse peak
Threshold voltage.Buck switch from shutdown is transferred on state, and pulse voltage is applied directly on test product winding at this time, pulse current by
Gradually rise.After test product electric current reaches pulse current peak after setting according to attenuation ratio, Buck switch is disconnected, test product electric current
By freewheeling diode afterflow and it is down to zero.A cycle terminates at this time.Terminate after completing the cycle number of setting.Then it carries out
Remanent magnetism detection, if remanent magnetism is met the requirements, demagnetization terminates；If being unsatisfactory for requiring, user selects peak value according to the degree of remanent magnetism
Electric current continues to demagnetize.
Continued flow switch is closed always in the above process.If it is super that each half cycles reach the duration after demagnetization current peak value
Pressure demagnetizing time is crossed, then is disconnected with the concatenated continued flow switch of freewheeling diode, passes the current through de-excitation resistance, electric current is accelerated to decline
Subtract.If being abnormal need to force that electric current is made quickly to be down to zero, continued flow switch disconnection is controlled, de-excitation resistance is passed the current through, adds
Fast current attenuation simultaneously is forced to terminate demagnetization process.
To reduce impact of the step voltage to transformer winding, flat wave capacitor can be gradually risen to take in every half of cycle
The method of voltage, i.e., flat wave capacitor voltage is from liter above freezing after Buck switch conduction.Compared to step voltage mode, it is tested winding electricity
Stream, which has, becomes apparent from electric current uphill process.It needs to be arranged in advance flat wave capacitor voltage when taking this approach and rises to arteries and veins from 0 volt
The time of crest voltage is rushed, which is usually no more than 5 seconds.If main circuit current reaches demagnetization current peak in voltage uphill process
Value, then Buck switch is closed, and test product electric current is gradually decreased to zero through freewheeling diode, this half of cycle terminates.
The process of pulsating direct current demagnetization are as follows: positive and negative step voltage signal is applied to subject winding first, judges the pole of remanent magnetism
Property and degree, then to peak impulse voltage, demagnetization peak point current, demagnetization valley point current and demagnetization the time be configured；It completes
Enter demagnetization phase after setting, instrument software is started from scratch the record demagnetization time；Inverting module circuit operation, Buck buck chopper
Circuit to transformer apply voltage direction adjust it is reversed to transformer remanence direction.Controllable rectifier module work, adjust automatically
Flat wave capacitor voltage is to setting peak impulse voltage.Buck switch is transferred on state from shutdown, and subject winding is applied pulse
Crest voltage, winding current gradually rise up to demagnetization peak point current.Then Buck switch OFF, winding current pass through two pole of afterflow
Pipe afterflow, electric current are gradually reduced.Buck switch is connected again after electric current is down to demagnetization valley point current, and winding current continues to rise,
Reach to enter after demagnetizing peak point current and turn off again.Buck switch switchs repeatedly, makes winding current in demagnetization peak point current and moves back
Change between magnetic valley point current.Pulsating direct current demagnetization process stops after reaching the demagnetization time manually set, and is remained automatically
Magnetic testi, user's selection continue pulsating direct current demagnetization or low-frequency ac demagnetization.
If being abnormal need to force that electric current is made quickly to be down to zero, continued flow switch disconnection is controlled, passes the current through demagnetization electricity
Resistance accelerates current attenuation and forces to terminate demagnetization process.
Walkie high-current demagnetization instrument and demagnetizing method described in the utility model based on Switching Power Supply can not only be complete
At the demagnetization function of transformer, reactor, additionally it is possible to complete the remanent magnetism detection function of transformer, reactor.
Above embodiment is only that the preferred embodiment of the utility model patent is described, not to this patent
Range is defined, under the premise of not departing from this patent design spirit, the various changes of the technical solution of the utility model patent
Shape and improvement should all fall into the protection scope that claims of the utility model patent determine.
Claims (4)
- The instrument 1. a kind of walkie high-current based on Switching Power Supply demagnetizes, it is characterised in that: the decompression including being sequentially connected electrically becomes Depressor, controllable rectifier module, flat wave capacitor, buck chopper module and inverting module；It further include rectification drive module, Chopper driving Module and single chip control module；The step-down transformer and controllable rectifier module are electrically connected with rectification drive module；Institute Flat wave capacitor is stated to be electrically connected with Chopper driving module and single chip control module respectively；The Chopper driving module is cut with decompression Wave module is electrically connected；The single chip control module respectively with inverting module, Chopper driving module and rectification drive module phase Electrical connection.
- The instrument 2. walkie high-current according to claim 1 based on Switching Power Supply demagnetizes, it is characterised in that: the rectification Drive module includes the synchronous generator being sequentially connected electrically, commutation controller and silicon-controlled driving；The synchronization signal hair Raw device is electrically connected with aforementioned step-down transformer；The silicon-controlled driving is electrically connected with aforementioned controllable rectifier module.
- The instrument 3. walkie high-current according to claim 2 based on Switching Power Supply demagnetizes, it is characterised in that: the copped wave Drive module includes the voltage and current sample circuit being sequentially connected electrically, feedback loop, chop control chip and IGBT driving；It is described Voltage and current sample circuit is electrically connected with aforementioned flat wave capacitor；The IGBT driving is electrically connected with buck chopper module.
- The instrument 4. walkie high-current according to claim 3 based on Switching Power Supply demagnetizes, it is characterised in that: the monolithic Machine control module includes AD sample circuit, protective module, rectified voltage DA output circuit, chopper current DA output circuit, monolithic Machine, commutation control module and display and key module；The display is successively electric with key module, single-chip microcontroller and commutation control module Connection；The AD sample circuit, protective module, rectified voltage DA output circuit, chopper current DA output circuit are and single-chip microcontroller It is electrically connected；The protective module is electrically connected with rectified voltage DA output circuit and chopper current DA output circuit respectively；Institute AD sample circuit is stated to be electrically connected with aforementioned flat wave capacitor and inverting module respectively；The rectified voltage DA output circuit with it is aforementioned Commutation controller is electrically connected；The chopper current DA output circuit is electrically connected with aforementioned chop control chip；The commutation Control module is electrically connected with aforementioned inverting module.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201821356885.9U CN208722672U (en) | 2018-08-22 | 2018-08-22 | A kind of walkie high-current demagnetization instrument based on Switching Power Supply |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201821356885.9U CN208722672U (en) | 2018-08-22 | 2018-08-22 | A kind of walkie high-current demagnetization instrument based on Switching Power Supply |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN208722672U true CN208722672U (en) | 2019-04-09 |
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ID=65979131
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| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201821356885.9U Expired - Fee Related CN208722672U (en) | 2018-08-22 | 2018-08-22 | A kind of walkie high-current demagnetization instrument based on Switching Power Supply |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN208722672U (en) |
-
2018
- 2018-08-22 CN CN201821356885.9U patent/CN208722672U/en not_active Expired - Fee Related
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