CN107086770A - Pfc circuit and transducer air conditioning - Google Patents
Pfc circuit and transducer air conditioning Download PDFInfo
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- CN107086770A CN107086770A CN201710530961.7A CN201710530961A CN107086770A CN 107086770 A CN107086770 A CN 107086770A CN 201710530961 A CN201710530961 A CN 201710530961A CN 107086770 A CN107086770 A CN 107086770A
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- igbt pipes
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- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02M—APPARATUS FOR CONVERSION BETWEEN AC AND AC, BETWEEN AC AND DC, OR BETWEEN DC AND DC, AND FOR USE WITH MAINS OR SIMILAR POWER SUPPLY SYSTEMS; CONVERSION OF DC OR AC INPUT POWER INTO SURGE OUTPUT POWER; CONTROL OR REGULATION THEREOF
- H02M1/00—Details of apparatus for conversion
- H02M1/42—Circuits or arrangements for compensating for or adjusting power factor in converters or inverters
- H02M1/4208—Arrangements for improving power factor of AC input
- H02M1/4233—Arrangements for improving power factor of AC input using a bridge converter comprising active switches
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R19/00—Arrangements for measuring currents or voltages or for indicating presence or sign thereof
- G01R19/175—Indicating the instants of passage of current or voltage through a given value, e.g. passage through zero
-
- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02M—APPARATUS FOR CONVERSION BETWEEN AC AND AC, BETWEEN AC AND DC, OR BETWEEN DC AND DC, AND FOR USE WITH MAINS OR SIMILAR POWER SUPPLY SYSTEMS; CONVERSION OF DC OR AC INPUT POWER INTO SURGE OUTPUT POWER; CONTROL OR REGULATION THEREOF
- H02M1/00—Details of apparatus for conversion
- H02M1/42—Circuits or arrangements for compensating for or adjusting power factor in converters or inverters
- H02M1/4208—Arrangements for improving power factor of AC input
- H02M1/4283—Arrangements for improving power factor of AC input by adding a controlled rectifier in parallel to a first rectifier feeding a smoothing capacitor
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02B—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO BUILDINGS, e.g. HOUSING, HOUSE APPLIANCES OR RELATED END-USER APPLICATIONS
- Y02B70/00—Technologies for an efficient end-user side electric power management and consumption
- Y02B70/10—Technologies improving the efficiency by using switched-mode power supplies [SMPS], i.e. efficient power electronics conversion e.g. power factor correction or reduction of losses in power supplies or efficient standby modes
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- Engineering & Computer Science (AREA)
- Power Engineering (AREA)
- Rectifiers (AREA)
Abstract
The invention provides a kind of pfc circuit and transducer air conditioning, include constituting rectification module by the branch circuit parallel connection that diode is composed in series with the IGBT pipes for carrying fly-wheel diode by setting two, and reactor connects the input of AC power, reactor, rectification module are connected in ac power supply circuit, rectification module output end is connected in parallel on after first electric capacity and the series connection of the second electric capacity, and switch module one end connects ac power supply circuit, the other end connects the common contact of the first electric capacity and the second electric capacity.The pfc circuit of the embodiment of the present invention is operationally, its current loop is at most only by two diodes including the fly-wheel diode of diode and IGBT pipes, by each diode of two rectifier bridge stacks the need for compared with the prior art, the working quantity of diode is greatly reduced, therefore reduces the waste that the heating loss of whole pfc circuit reduces energy.
Description
Technical field
The present invention relates to PFC control fields, more particularly to a kind of pfc circuit and transducer air conditioning.
Background technology
The driving frequency-changeable compressor or the PFC of direct current generator being currently used under low-voltage such as 100VAC supply voltages
(Power Factor Correction, Active PFC) circuit is existing generally using power supply is exported again after voltage multiplying rectifier
The pfc circuit of voltage multiplying rectifier scheme all includes two rectifier bridge stacks, wherein a bridge heap is used for voltage multiplying rectifier, one is served only in addition
Powered after full-wave rectification to PFC parts, in the whole pfc circuit course of work, each diode a total of 8 of this two bridge heaps
Individual diode will work, and because the operating current of pfc circuit is big, therefore the heating of the two bridge heaps is big, causes very big energy
Waste.And existing pfc circuit can only operate under voltage multiplying rectifier mode, loaded work piece in a low-power state when exist
The problem of conversion efficiency is relatively low, therefore cause the waste of energy.
The content of the invention
It is a primary object of the present invention to provide a kind of pfc circuit and transducer air conditioning, it is therefore intended that solve existing multiplication of voltage
The pfc circuit bridge heap heating of rectifier system is big and there is the problem of conversion efficiency is low under low power load.
To achieve the above object, a kind of pfc circuit for providing of the present invention, including reactor, rectification module, switch module,
First electric capacity, the second electric capacity, controller and drive module;
The reactor connects the input of AC power, and the reactor, rectification module are connected on ac power supply circuit
In;
The rectification module output end is connected in parallel on after first electric capacity and the second electric capacity series connection,
The drive module is connected in parallel on the rectification module output end, the rectification module to the AC rectification of input into
Direct current, to provide power supply for drive module work, the drive module control end connects the controller, the control
Device controls the drive module to be run with driving load;
The rectification module includes the first rectification unit and the second rectification unit, and first rectification unit includes the one or two
Pole pipe and the first IGBT pipes, second rectification unit includes the second diode and the 2nd IGBT is managed, first rectification unit
In parallel with the second rectification unit, first rectification unit and the second rectification unit include by diode respectively and carry afterflow two
The branch road that the IGBT pipes of pole pipe are composed in series, the control end of two IGBT pipes of the rectification module connects the control respectively
Device, two IGBT pipes of the rectification module carry out switch switching under control of the controller, with what is exported to the rectification module
DC voltage and DC current carry out Active PFC;
Described switch module one end connects the ac power supply circuit, and the other end connects first electric capacity and the second electric capacity
Common contact, the control end of the switch module connects the controller, and the controller controls the break-make of the switch module,
To be constituted rectification circuit by rectification module and first electric capacity and the second electric capacity described in control and be realized full-bridge rectification and multiplication of voltage
Rectification switches.
The positive pole of first diode connects the source class of the first IGBT pipes, the positive pole connection of second diode
The source class of the 2nd IGBT pipes, first diode cathode is in parallel with the negative pole of second diode as the rectification
The cathode output end of module, the drain electrode of the first IGBT pipes is in parallel with the drain electrode of the 2nd IGBT pipes as the rectification mould
The cathode output end of block.
The positive pole of first diode connects the source class of the first IGBT pipes, the positive pole connection of second diode
The source class of the 2nd IGBT pipes, the source class and the source class of the 2nd IGBT pipes of the first IGBT pipes is in parallel as described whole
The cathode output end of flow module, first diode cathode is in parallel with the negative pole of second diode as the rectification mould
The cathode output end of block.
It is preferred that, one end of the switch module connects the zero line input of the alternating voltage, and other end connection is described
The common contact of first electric capacity and the second electric capacity.
It is preferred that, one end of the switch module connects the live wire input of the alternating voltage, and other end connection is described
The common contact of first electric capacity and the second electric capacity.
It is preferred that, in addition to current detection module,
The current detection module is series at the ac circuit, and the output end of the current detection module connects the control
Device processed, to detect the AC current values of the AC power input.
It is preferred that, in addition to zero passage detection module,
The zero passage detection wired in parallel connects institute in the ac power input end, the zero passage detection module output end
Controller is stated, to detect the voltage zero-crossing signal of the AC power, the controller is controlled according to the voltage zero-crossing signal
The on off state of two IGBT pipes of the rectification module is switched over.
It is preferred that, in addition to voltage detection module,
The voltage detection module is connected in parallel on the rectification module output end, the output end connection of the voltage detection module
The controller, to detect the DC voltage value of the rectification module output.
It is preferred that, when the load is compressor, the controller is additionally operable to:
Judge the frequency of current control compressor operating, when the running frequency is more than preset value, the controller control
The switch module conducting is made, to control the current rectifying and wave filtering circuit to be operated in voltage multiplying rectifier pattern;When the running frequency is small
When the preset value, the controller controls the second switch module to disconnect, to control the current rectifying and wave filtering circuit to work
In full-bridge rectification pattern.
To achieve the above object, the present invention also provides a kind of transducer air conditioning, and the transducer air conditioning includes described PFC
Circuit.
The pfc circuit that the present invention is provided, by setting two IGBT pipes for including by diode and carrying fly-wheel diode
The branch circuit parallel connection being composed in series constitutes rectification module, and reactor connects the input of AC power, reactor, rectification module string
It is associated in ac power supply circuit, rectification module output end, and switch module one is connected in parallel on after the first electric capacity and the series connection of the second electric capacity
End connection ac power supply circuit, the other end connects the common contact of the first electric capacity and the second electric capacity.The pfc circuit of the embodiment of the present invention
Operationally, two diodes that its current loop at most only passes through including the fly-wheel diode of diode and IGBT pipes,
By each diode of two rectifier bridge stacks the need for compared with the prior art, the working quantity of diode is greatly reduced, because
This heating loss for reducing whole pfc circuit reduces the waste of energy.Moreover, by switch module realize full-bridge rectification and
The switching of voltage multiplying rectifier pattern, realize when loaded work piece in a low-power state when, pfc circuit remains to realize high-conversion rate,
Conversion efficiency is low under low power scenarios causes energy dissipation to ask for the pfc circuit of the single voltage multiplying rectifier pattern in the prior art of solution
Topic.
Brief description of the drawings
Fig. 1 is the electrical block diagram of pfc circuit first embodiment of the present invention;
Fig. 2 be first embodiment in be operated in current loop schematic diagram of the reactor in energy storage under full-bridge rectification pattern;
Fig. 3 returns to be operated in first embodiment under full-bridge rectification pattern to the electric current that the first electric capacity and the second electric capacity charge
Road schematic diagram;
Fig. 4 shows to be operated in another current loops of the reactor L in energy storage under full-bridge rectification pattern in first embodiment
It is intended to;
Fig. 5 is to be operated in another electricity charged under full-bridge rectification pattern to the first electric capacity and the second electric capacity in first embodiment
Flow circuit diagram;
Fig. 6 be first embodiment in be operated under voltage multiplying rectifier pattern to the first electric capacity charge current loop schematic diagram;
Fig. 7 be first embodiment in be operated under voltage multiplying rectifier pattern to the second electric capacity charge current loop schematic diagram;
Fig. 8 is the electrical block diagram of pfc circuit second embodiment of the present invention;
Fig. 9 be second embodiment in be operated under voltage multiplying rectifier pattern to the second electric capacity charge current loop schematic diagram;
Figure 10 be second embodiment in be operated under voltage multiplying rectifier pattern to the first electric capacity charge current loop schematic diagram;
Figure 11 is the electrical block diagram of pfc circuit 3rd embodiment of the present invention;
Figure 12 is the electrical block diagram of pfc circuit fourth embodiment of the present invention.
Embodiment
Embodiments of the invention are described below in detail, the example of the embodiment is shown in the drawings, wherein from beginning to end
Same or similar label represents same or similar element or the element with same or like function.Below with reference to attached
The embodiment of figure description is exemplary, it is intended to for explaining the present invention, and be not considered as limiting the invention.
Reference picture 1, the pfc circuit structure chart that Fig. 1 provides for first embodiment of the invention, for convenience of description, only shows
The part related to the embodiment of the present invention, details are as follows:
Pfc circuit provided in an embodiment of the present invention includes reactor L, rectification module 10, switch module 20, the first electric capacity
E1, the second electric capacity E2, controller 30 and drive module 40;
The input of reactor L connection AC powers, reactor L, rectification module 10 are connected in ac power supply circuit;
The output end of rectification module 10 is connected in parallel on after first electric capacity E1 and the second electric capacity E2 series connection,
Drive module 40 is connected in parallel on the output end of rectification module 10, and the AC rectifications of 10 pairs of inputs of rectification module is into direct current
Electricity, to provide power supply, the control end of drive module 40 connection controller 30, the control driving mould of controller 30 for the work of drive module 40
Block 40 is run with driving load;
Rectification module 10 includes the first rectification unit 11 and the second rectification unit 12, and first rectification unit 11 includes the
One diode D1 and the first IGBT pipe Q1, second rectification unit 12 includes the second diode D2 and the 2nd IGBT pipe Q2, the
One rectification unit 11 and the second rectification unit 12 are in parallel, and the first rectification unit 11 and the second rectification unit 12 include by two poles respectively
Manage and carry IGBT pipes (the Insulated Gate Bipolar Transistor, insulated gate bipolar crystal of fly-wheel diode
Pipe) branch road that is composed in series, the control end of two IGBT pipes of rectification module 10 connects controller 30 respectively, rectification module 10
Two IGBT pipes carry out switch switching under the control of controller 30, with the DC voltage and DC current exported to rectification module 10
Carry out Active PFC;
The one end of switch module 20 connects ac power supply circuit, and other end connection the first electric capacity E1's and the second electric capacity E2 connects altogether
Point, the control end connection controller 30 of switch module 20, the break-make of the controlling switch module 20 of controller 30, to control by rectification mould
The electric capacity E1 of block 10 and first and the second electric capacity E2 composition rectification circuits realize full-bridge rectification and voltage multiplying rectifier switching.
Specifically, switch module 20 includes the switch K1 mono- of switch K1 and driving switch K1 switch drive unit 1 here
As be relay, the drive circuit that switch drive unit is constituted for the circuit of corresponding driving relay if any triode, three poles
The controlled stage of pipe is that base stage is the control end of first switch module 20, and the switch ends of relay are the two of first switch module 20
End, controller 60 is that a MCU control port passes through break-make of the output signal by switch drive unit controlling switch K1.This
In because the switch drive unit of relay and driving relay is prior art, its physical circuit do not repeating.
First rectification unit 11 of rectification module 10 includes the first diode D1 and the first IGBT pipe Q1, the second rectification unit
12 include the second diode D2 and the 2nd IGBT pipes Q2;
First diode D1 positive pole connects the first IGBT pipes Q1 colelctor electrode, the second diode D2 positive pole connection second
IGBT pipes Q2 colelctor electrode, the first diode D1 negative poles and the second diode D2 the negative pole positive pole in parallel as rectification module 10
Output end, the first IGBT pipes Q1 emitter stage negative pole as rectification module 10 in parallel with the 2nd IGBT pipes Q2 emitter stage is exported
End.
One end of switch module 20 connects the zero line input of AC power, and the other end connects the electricity of the first electric capacity E1 and second
Hold E2 common contact.
The pfc circuit of the present embodiment also includes zero passage detection module 60, and it is defeated that zero passage detection module 60 is connected in parallel on AC power
Enter end, the output end of zero passage detection module 60 connection controller 30, to detect the voltage zero-crossing signal of AC power, controller according to
The on off state of two IGBT pipes of voltage zero-crossing signal control rectification module 10 is switched over.Zero passage detection module 60 it is specific
Circuit refers to prior art, will not be repeated here.
The pfc circuit of the present embodiment also includes current detection module 50, and current detection module 50 is series at ac circuit, schemes
Current detection module 50 is connected on the zero line of AC power in 1, naturally it is also possible to be connected on the zero line side of AC power, electric current
The output end connection controller 30 of detection module 50, to detect the AC current values of AC power input.Current detection module 50
By being constituted including current transformer T1 and additional detection circuit, the physical circuit of current detection module 50 refers to prior art,
It will not be repeated here.
The pfc circuit of the present embodiment also includes voltage detection module 70, and voltage detection module 70 is connected in parallel on rectification module 10
Output end, the output end connection controller 30 of voltage detection module 70, to detect the DC voltage value of the output of rectification module 10.Electricity
Detection module 70 is pressed to refer to prior art using the ball bearing made composition based on electric resistance partial pressure structure type, physical circuit,
It will not be repeated here.
Pfc circuit operation principle shown in the present embodiment is as follows:When the K1 of switch module 20 disconnects, by rectification module 10
Full-bridge rectification pattern is operated in the first electric capacity E1 and the second electric capacity E2 current rectifying and wave filtering circuits constituted.As shown in Fig. 2 when control
When device 30 processed controls the first IGBT pipes Q1 conductings, the 2nd IGBT pipes Q2 cut-offs, now AC power electric current is L lines from live wire
Through reactor L, the first IGBT pipes Q1 collector and emitter, the 2nd IGBT pipes Q2 sustained diode 4 positive pole and negative pole
Return to AC power zero line i.e. N lines and constitute loop, realize the energy storage to reactor L;As shown in figure 3, when the control of controller 30 the
When one IGBT pipes Q1 ends, induced electromotive force is produced on reactor L, its sense of current for flowing through reactor L and the first IGBT are managed
Q1 cut-off before be consistent, now reactor L induced electromotive force produce electric current through the first diode D1, the first electric capacity E1,
Second electric capacity E2, the 2nd IGBT pipes Q2 sustained diode 4 constitute current loop to fill the first electric capacity E1 and the second electric capacity E2
Electricity, with this realize AC power electric current from L line starting directions when the DC voltage and electric current that are exported from rectification module 10
Active PFC.As shown in figure 4, when controller 30 controls the 2nd IGBT pipes Q2 conductings, the first IGBT pipes Q1 cut-offs, now
AC power electric current is from the afterflow that live wire is collector and emitter of the N lines through the 2nd IGBT pipes Q2, the first IGBT pipes Q1
Diode D3 positive pole and negative pole, reactor L returns to AC power zero line i.e. L lines and constitutes loop, realizes the storage to reactor L
Energy;As shown in figure 5, when controller 30 controls the 2nd IGBT pipes Q2 cut-offs, producing induced electromotive force on reactor L, it is flowed through
The reactor L sense of current is consistent before ending with the 2nd IGBT pipes Q2, the electricity that now reactor L induced electromotive force is produced
Flow through the second diode D2, the first electric capacity E1, the second electric capacity E2, the first IGBT pipes Q1 sustained diode 3 and constitute current loop
With to the first electric capacity E1 and the second electric capacity E2 chargings, with this realize AC power electric current from N line starting directions when from rectification
The Active PFC of DC voltage and electric current that module 10 is exported.Above-mentioned reactor L produce induced electromotive force to first
In electric capacity E1 and the second electric capacity E2 charging processes, the first diode D1, the second diode D2, the first IGBT pipes Q1 pole of afterflow two
Pipe D3 and the 2nd IGBT pipes Q2 sustained diode 4 constitute full-bridge rectification mode, therefore, and controller passes through control first respectively
IGBT pipes Q1 and the 2nd IGBT pipes Q2 alternate conduction and cut-off, realize the Active PFC work(under full-bridge rectification pattern
Energy.
When switch module 20 K1 closure when, by the electric capacity E1 of rectification module 10 and first and the second electric capacity E2 constitute it is whole
Stream filter circuit is operated in voltage multiplying rectifier pattern.When controller 30 controls the first IGBT pipes Q1 conductings, the 2nd IGBT pipes Q2 cut-offs
When, AC power electric current is identical with Fig. 2 from the loop of L lines, realizes the energy storage to reactor L;As shown in fig. 6, when control
When device 30 processed controls the first IGBT pipes Q1 cut-offs, induced electromotive force is produced on reactor L, it flows through the reactor L sense of current
With the first IGBT pipes Q1 cut-off before be consistent, now reactor L induced electromotive force produce electric current through the first diode D1,
First electric capacity E1, switch K1 constitute loop to be charged to the first electric capacity E1, realize AC power electric current with this and go out originating party from L lines
To when from rectification module 10 export DC voltage and electric current Active PFC.When controller 30 controls the 2nd IGBT pipes
When Q2 conductings, the first IGBT pipes Q1 cut-offs, AC power electric current is identical with Fig. 4 from the loop of N lines, realizes to reactor
L energy storage;As shown in fig. 7, when controller 30 controls the 2nd IGBT pipes Q2 cut-offs, induced electromotive force is produced on reactor L, its
The reactor L sense of current is flowed through with being consistent before the 2nd IGBT pipes Q2 cut-offs, now reactor L induced electromotive force is produced
Electric current through switch K1, the second electric capacity E2, the first IGBT pipes Q1 sustained diode 3 into current loop with to the second electric capacity E2
Charging, with this realize AC power electric current from N line starting directions when from rectification module 10 export DC voltage and electric current
Active PFC.The opposed polarity induced electromotive force that above-mentioned reactor L is produced is respectively to the first electric capacity E1 and the second electric capacity
E2 charges, therefore the first electric capacity E1 and the voltage at the second electric capacity E2 two ends are one times of voltage on single electric capacity, realize multiplication of voltage
Rectifier system.Therefore, controller is real respectively by controlling the first IGBT pipes Q1 and the 2nd IGBT pipes Q2 alternate conduction and cut-off
The Active PFC function under voltage multiplying rectifier pattern is showed.
Pfc circuit shown in the present embodiment, the load that drive module 40 drives includes compressor or motor, pressure here
Contracting machine or motor are permagnetic synchronous motor, and drive module is included by IPM modules (Intelligent Power Module, intelligence
Power model) composition circuit, under the control of controller 30, realize will the DC inverter that be carried in IPM modules into exchange
Electricity realizes the driving to compressor or motor.Operationally, what it is due to pfc circuit input is to hand over to the pfc circuit of the present embodiment
Flow electric current, it is therefore desirable to ensure to maintain electric current in the first IGBT pipes Q1 or the 2nd IGBT pipes Q2 work, to realize to reactor L
Energy storage, thus controller needed to detect the zero cross signal of alternating current by zero detection module 60, and the is just controlled after zero passage
One IGBT pipes Q1 or the 2nd IGBT pipes turn on to guarantee to realize the energy storage to reactor L by lasting electric current.And PFC electricity
In the course of the work, controller 30 also needs to obtain the operating current of current circuit by current detection module 50 on road, if hair
The operating current now loaded is too high, when causing the operating current of pfc circuit too high, controller 30 control two IGBT pipes to close with
Close the whole pfc circuit of pfc circuit work protection.In the process, controller 30 is also needed to by electricity the pfc circuit of the present embodiment
The DC voltage for pressing the detection rectification module output in real time of detection module 70 is DC bus-bar voltage, higher in d-c bus voltage value
When, the pwm value that can be turned on by the first IGBT pipes Q1 of adjustment or the 2nd IGBT pipes, to reduce the d-c bus voltage value of output,
Realize the stabilization of d-c bus voltage value.
The pfc circuit of the present embodiment from the above-mentioned course of work it is recognised that when being operated under full-bridge rectification pattern,
During reactor L energy storage, current loop only passes through the fly-wheel diode of one of IGBT pipes, and produces induced electricity in reactor L
When kinetic potential charges to the first electric capacity E1 and the second electric capacity E2, current loop only a diode therethrough and one of them
The fly-wheel diode of IGBT pipes;When being operated under voltage multiplying rectifier pattern, in reactor L energy storage, current loop only passes through it
In an IGBT pipe fly-wheel diode, and reactor L produce induced electromotive force the first electric capacity E1 and the second electric capacity E2 are filled
When electric, the fly-wheel diode of current loop only a diode or one of IGBT pipes therethrough.Therefore it is relatively existing
When having the pfc circuit work of two rectifier bridge stacks of sampling of technology, each diode of every bridge heap is worked, and the present invention is implemented
The pfc circuit of example operationally greatly reduces the working quantity of diode, therefore reduces the heating loss of whole pfc circuit
Reduce the waste of energy.
Current rectifying and wave filtering circuit shown in the present embodiment is suitable for when the exchange of input when being operated under voltage multiplying rectifier pattern
When the alternating current of low voltage such as input is 100V, the DC voltage of output can be lifted by voltage multiplying rectifier, to load as pressure
Exemplified by contracting machine, when compressor operating is under high power environment, due to needing relatively high voltage to drive its normal work,
Therefore voltage multiplying rectifier is needed to lift the d-c bus voltage value of output.And when under low power load, if compressor work
Make under low frequency state, when being such as less than preset value 20Hz with the working frequency of compressor, now the operating current of circuit is low, due to
Pfc circuit conversion efficiency now under voltage multiplying rectifier pattern is low, and now compressor can need not high operating voltage relatively
It is worth, therefore the controlling switch module 20 of controller 30 disconnects, and current rectifying and wave filtering circuit is allowed when being operated under full-bridge rectification pattern, due to complete
The conversion efficiency lifting of pfc circuit under bridge rectification mode, the efficiency that can now improve whole pfc circuit reduces energy dissipation.
Specifically, controller 30 needs to obtain the frequency of current compressor, if the frequency of compressor is current compression less than preset value
Machine operating current is relatively low, and controlling switch module 20 disconnects to allow current rectifying and wave filtering circuit to be operated in full-bridge rectification pattern improving PFC
Circuit conversion efficiency;The controlling switch module if the frequency of compressor is the increase of current compressor operating current more than preset value
20 turn on to allow current rectifying and wave filtering circuit to be operated in voltage multiplying rectifier pattern to improve loaded work piece voltage to maintain the normal work of load
Make.
Pfc circuit provided in an embodiment of the present invention, by setting two to include by diode and carrying fly-wheel diode
The branch circuit parallel connection composition rectification module 10 that IGBT pipes are composed in series, and the input of reactor L connection AC powers, reactor L,
Rectification module 10 is connected in ac power supply circuit, and to be connected in parallel on rectification module 10 defeated after the first electric capacity E1 and the second electric capacity E2 series connection
Go out end, and switch module one end connection ac power supply circuit, the other end connects the first electric capacity E1 and the second electric capacity E2 common contact.
Operationally, its current loop is at most only by including the afterflow two of diode and IGBT pipes for the pfc circuit of the embodiment of the present invention
Two diodes including pole pipe, compared with the prior art the need for by two rectifier bridge stacks each diode, greatly reduce
The working quantity of diode, therefore reduce the waste that the heating loss of whole pfc circuit reduces energy.Moreover, passing through
Switch module realizes the switching of full-bridge rectification and voltage multiplying rectifier pattern, realize when loaded work piece in a low-power state when, PFC
Circuit remains to realize high-conversion rate, and the pfc circuit for solving single voltage multiplying rectifier pattern in the prior art turns under low power scenarios
Change that efficiency is low to cause energy dissipation problem.
Further, based on pfc circuit first embodiment of the present invention, pfc circuit such as Fig. 8 institutes of second embodiment of the invention
Show, it is different from the circuit connecting mode that first embodiment is a difference in that switch module 20.
One end of switch module 20 connects the live wire input of AC power, and the other end connects the electricity of the first electric capacity E1 and second
Hold E2 common contact.
In the present embodiment, switch module 20 is changed to be connected to the live wire i.e. L line ends of nearly AC power, is specifically connected in parallel on
Between reactor L and an ac input end of rectification module 20.
The pfc circuit of the present embodiment operation principle and first embodiment when switch module disconnects and is in full-bridge rectification pattern
It is identical.When switch module closed loop is under voltage multiplying rectifier pattern, cause when the first IGBT pipes Q1 or the 2nd IGBT pipes Q2 is turned on
Reactor L be in energy storage state under when its operation principle it is identical with first embodiment, be a difference in that ought the first IGBT pipes Q1 or
The current loop that 2nd IGBT pipes Q2 ends the induced electromotive force formation that reactor L is produced is different.As shown in figure 9, when the
One IGBT pipes Q1 from conducting become cut-off when, produce induced electromotive force on reactor L, its flow through the reactor L sense of current with
It is consistent before first IGBT pipes Q1 cut-offs, the electric current that now reactor L induced electromotive force is produced is through switching K1, the second electric capacity
E2, the 2nd IGBT pipes Q2 sustained diode 4 constitute loop to be charged to the second electric capacity E2, and AC power electricity is realized with this
Flow from L line starting directions when from rectification module 10 export DC voltage and electric current Active PFC;As shown in Figure 10,
When the 2nd IGBT pipes Q2 becomes cut-off from conducting, induced electromotive force is produced on reactor L, it flows through reactor L electric current side
To with being consistent before the 2nd IGBT pipes Q2 cut-offs, the electric current that now reactor L induced electromotive force is produced is through the second diode
D2, the first electric capacity E1, switch K1 constitute loop to be charged to the first electric capacity E1, realize AC power electric current with this and go out from N lines
Originating party to when from rectification module 10 export DC voltage and electric current Active PFC.Above-mentioned charging process is only passed through
One diode, will will greatly reduce, therefore reduce whole by each diode of two rectifier bridge stacks compared with the prior art
The heating loss of individual pfc circuit.
Further, based on pfc circuit first embodiment of the present invention, pfc circuit such as Figure 11 of third embodiment of the invention
It is shown, it is different from the circuit structure that first embodiment is a difference in that rectification module 10.
The positive pole of first diode connects the first IGBT pipes Q1 colelctor electrode, and the positive pole of the second diode connects the 2nd IGBT
Pipe Q2 colelctor electrode, the first diode cathode cathode output end as rectification module in parallel with the negative pole of the second diode, the
One IGBT pipes Q1 emitter stage and the 2nd IGBT pipes Q2 emitter stage cathode output end in parallel as rectification module.I.e. first is whole
The link position for flowing the diode in the rectification unit 12 of unit 11 and second and IGBT pipes is exchanged with respect to first embodiment.
The pfc circuit principle of the present embodiment is similar to first embodiment, in the first IGBT pipes Q1 of pfc circuit or second
When IGBT pipes Q2 is turned on, fly-wheel diode of its electric current in current loop respectively through one of IGBT pipes and another
The collector and emitter of IGBT pipes is with to reactor L energy storage;And become in the first IGBT pipes Q1 or the 2nd IGBT pipes Q2 conductings
During cut-off, the induced electromotive force difference switch module 20 that its reactor L is produced is disconnected and closed loop is formed full-bridge rectification and multiplication of voltage
Rectification mode charges to the first electric capacity E1 and the second electric capacity E2, and its charge circuit at most only passes through a diode and an IGBT
The fly-wheel diode of pipe, it is identical with the diode operation quantity of first embodiment, therefore equally greatly reduce compared with the prior art
The working quantity of diode, therefore reduce the waste that the heating loss of whole pfc circuit reduces energy.
Further, based on pfc circuit 3rd embodiment of the present invention, pfc circuit such as Figure 12 of fourth embodiment of the invention
It is shown, it is different from the circuit connecting mode that 3rd embodiment is a difference in that switch module 20.The connected mode of switch module 20
With the circuit connecting mode of switch module in second embodiment 20.
The pfc circuit principle of the present embodiment is similar to 3rd embodiment, in the pfc circuit course of work, its current loop
In at most only by the fly-wheel diodes of a diodes and an IGBT pipes, the diode operation quantity phase with first embodiment
Together, the working quantity of diode therefore is equally greatly reduced compared with the prior art, therefore reduces the heating of whole pfc circuit
Loss reduces the waste of energy.
The present invention also provides a kind of transducer air conditioning, by indoor set, outdoor unit into wherein outdoor unit compresses including frequency conversion
Machine, outdoor unit control circuit includes above-mentioned pfc circuit, and its specific embodiment refers to above-described embodiment, herein no longer
Repeat.
In the description of this specification, the description meaning of reference term " first embodiment ", " second embodiment ", " example " etc.
Refer to reference to specific method, device or the feature that the embodiment or example are described be contained in the present invention at least one embodiment or
In example.In this manual, identical embodiment or example are necessarily directed to the schematic representation of above-mentioned term.And
And, specific features, method, device or the feature of description can be in any one or more embodiments or example with suitable side
Formula is combined.In addition, in the case of not conflicting, those skilled in the art can be real by the difference described in this specification
The feature for applying example or example and non-be the same as Example or example is combined and combined.
The preferred embodiments of the present invention are these are only, are not intended to limit the scope of the invention, it is every to utilize this hair
Equivalent structure or equivalent flow conversion that bright specification and accompanying drawing content are made, or directly or indirectly it is used in other related skills
Art field, is included within the scope of the present invention.
Claims (10)
1. a kind of power factor correction circuit, it is characterised in that including reactor, rectification module, switch module, the first electric capacity,
Second electric capacity, controller and drive module;
The reactor connects the input of AC power, and the reactor, rectification module are connected in ac power supply circuit;
The rectification module output end is connected in parallel on after first electric capacity and the second electric capacity series connection,
The drive module is connected in parallel on the rectification module output end, and the rectification module is to the AC rectification of input into direct current
Electricity, to provide power supply for drive module work, the drive module control end connects the controller, the controller control
The drive module is made to run with driving load;
The rectification module includes the first rectification unit and the second rectification unit, and first rectification unit includes the first diode
With the first IGBT pipes, second rectification unit includes the second diode and the 2nd IGBT and managed, first rectification unit and the
Two rectification units are in parallel, and first rectification unit and the second rectification unit include by diode respectively and carry fly-wheel diode
The branch road that is composed in series of IGBT pipes, the control end of two IGBT pipes of the rectification module connects the controller, institute respectively
The two IGBT pipes for stating rectification module carry out switch switching under control of the controller, with the direct current exported to the rectification module
Pressure and DC current carry out Active PFC;
Described switch module one end connects the ac power supply circuit, and the other end connects being total to for first electric capacity and the second electric capacity
Contact, the control end of the switch module connects the controller, and the controller controls the break-make of the switch module, to control
Constituted rectification circuit by rectification module and first electric capacity and the second electric capacity described in system and realized full-bridge rectification and voltage multiplying rectifier
Switching.
2. power factor correction circuit as claimed in claim 1, it is characterised in that
The positive pole of first diode connects the source class of the first IGBT pipes, and the positive pole connection of second diode is described
The source class of 2nd IGBT pipes, first diode cathode is in parallel with the negative pole of second diode as the rectification module
Cathode output end, the drain electrodes of the first IGBT pipes is in parallel with the drain electrode of the 2nd IGBT pipes as the rectification module
Cathode output end.
3. power factor correction circuit as claimed in claim 1, it is characterised in that
The positive pole of first diode connects the source class of the first IGBT pipes, and the positive pole connection of second diode is described
The source class of 2nd IGBT pipes, the source class of the first IGBT pipes is in parallel with the source class of the 2nd IGBT pipes as the rectification mould
The cathode output end of block, first diode cathode is in parallel with the negative pole of second diode as the rectification module
Cathode output end.
4. power factor correction circuit as claimed in claim 1, it is characterised in that
One end of the switch module connects the zero line input of the alternating voltage, and the other end connects first electric capacity
With the common contact of the second electric capacity.
5. power factor correction circuit as claimed in claim 1, it is characterised in that
One end of the switch module connects the live wire input of the alternating voltage, and the other end connects first electric capacity
With the common contact of the second electric capacity.
6. power factor correction circuit as claimed in claim 1, it is characterised in that also including current detection module,
The current detection module is series at the ac circuit, and the output end of the current detection module connects the control
Device, to detect the AC current values of the AC power input.
7. power factor correction circuit as claimed in claim 1, it is characterised in that also including zero passage detection module,
The zero passage detection wired in parallel connects the control in the ac power input end, the zero passage detection module output end
Device processed, to detect the voltage zero-crossing signal of the AC power, the controller is according to being controlled the voltage zero-crossing signal
The on off state of two IGBT pipes of rectification module is switched over.
8. power factor correction circuit as claimed in claim 1, it is characterised in that also including voltage detection module,
The voltage detection module is connected in parallel on the rectification module output end, and the output end connection of the voltage detection module is described
Controller, to detect the DC voltage value of the rectification module output.
9. power factor correction circuit as claimed in claim 1, it is characterised in that
When the load is compressor, the controller is additionally operable to:
Judge the frequency of current control compressor operating, when the running frequency is more than preset value, the controller controls institute
Switch module conducting is stated, to control the current rectifying and wave filtering circuit to be operated in voltage multiplying rectifier pattern;When the running frequency is less than institute
When stating preset value, the controller controls the second switch module to disconnect, to control the current rectifying and wave filtering circuit to be operated in entirely
Bridge rectification mode.
10. a kind of transducer air conditioning, including the power factor correction circuit as described in any one of claim 1 to 9.
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