CN114142718A - Active power factor correction circuit, switching power supply and vehicle - Google Patents
Active power factor correction circuit, switching power supply and vehicle Download PDFInfo
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- CN114142718A CN114142718A CN202111374012.7A CN202111374012A CN114142718A CN 114142718 A CN114142718 A CN 114142718A CN 202111374012 A CN202111374012 A CN 202111374012A CN 114142718 A CN114142718 A CN 114142718A
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- resistor
- pass filter
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- capacitor
- factor correction
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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
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- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02J—CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY
- H02J3/00—Circuit arrangements for ac mains or ac distribution networks
- H02J3/01—Arrangements for reducing harmonics or ripples
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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
- H02M1/12—Arrangements for reducing harmonics from ac input or output
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- 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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- 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
- Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
- Y02E40/00—Technologies for an efficient electrical power generation, transmission or distribution
- Y02E40/40—Arrangements for reducing harmonics
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- Engineering & Computer Science (AREA)
- Power Engineering (AREA)
- Rectifiers (AREA)
Abstract
The invention provides an active power factor correction circuit, a switching power supply and a vehicle, which comprise a power factor correction controller and an output voltage sampling circuit, wherein the active power factor correction circuit is provided with an output positive terminal and an output negative terminal, the power factor correction controller is provided with a voltage sampling terminal, the output voltage sampling circuit comprises an RC low-pass filter circuit and an RC high-pass filter circuit which are connected in parallel, the input end of the RC low-pass filter circuit and the input end of the RC high-pass filter circuit are connected with the output positive terminal, the grounding end of the RC low-pass filter circuit and the grounding end of the RC high-pass filter circuit are connected with the output negative terminal, and the output end of the RC low-pass filter circuit and the output end of the RC high-pass filter circuit are connected with the voltage sampling terminal. The band elimination filter function can be realized through the RC low-pass filter circuit and the RC high-pass filter circuit which are connected in parallel, so that the fluctuation of specific frequency on the output voltage sampling circuit can be filtered, and the input total harmonic current iTHD of the APFC circuit is improved.
Description
Technical Field
The invention relates to the field of power electronics, in particular to an active power factor correction circuit, a switching power supply and a vehicle.
Background
With the increasing development and wide application of power electronic devices and apparatuses, harmonic pollution in the power grid also becomes more serious, and the prior art generally reduces the harmonic pollution in the power grid by adopting a method of performing Power Factor Correction (PFC) on the power utilization equipment.
Referring to fig. 1, fig. 1 is a conventional power factor correction circuit (APFC circuit) in the prior art, which employs a power factor correction controller of an integrated circuit chip to implement control of the power factor correction circuit, and generally uses a resistance voltage division network to sample an output voltage, that is, a voltage sampling circuit 11 employing resistance voltage division is used in cooperation with a set of capacitors to enhance the anti-interference capability thereof, and connects a voltage sampling signal to a voltage sampling terminal of the APFC controller, so as to implement sampling of the output voltage of the APFC circuit and perform voltage stabilization control.
In a conventional single-phase input APFC circuit, because an active power instantaneous value of an alternating current input fluctuates, the output voltage of the APFC circuit also has voltage fluctuation, the fluctuation frequency is 2 times of the frequency of the alternating current input voltage, and when a resistance voltage division network is used for voltage sampling, the sampling result also contains the 2-time-multiplied fluctuation. For an APFC circuit controlled by an analog chip, a control circuit cannot filter out fixed frequency fluctuation of voltage sampling. When the voltage sampling signal with fixed frequency voltage fluctuation is used for APFC control, the voltage fluctuation influences the control effect of power factor correction, so that the input current generates odd harmonics, the input total harmonic current (iTHD) of an APFC circuit is poor, and the key performance of the APFC circuit is directly influenced.
Disclosure of Invention
It is a first object of the present invention to provide an active power factor correction circuit that filters out frequency-specific fluctuations on a voltage sample.
A second object of the present invention is to provide a switching power supply having the above active power factor correction circuit.
A third object of the present invention is to provide a vehicle having the above switching power supply.
In order to achieve the first object of the invention, the invention provides an active power factor correction circuit, which comprises a power factor correction controller and an output voltage sampling circuit, wherein the active power factor correction circuit is provided with an output positive terminal and an output negative terminal, the power factor correction controller is provided with a voltage sampling terminal, the output voltage sampling circuit comprises an RC low-pass filter circuit and an RC high-pass filter circuit which are connected in parallel, the input end of the RC low-pass filter circuit and the input end of the RC high-pass filter circuit are connected with the output positive terminal, the grounding end of the RC low-pass filter circuit and the grounding end of the RC high-pass filter circuit are connected with the output negative terminal, and the output end of the RC low-pass filter circuit and the output end of the RC high-pass filter circuit are connected with the voltage sampling terminal.
According to the scheme, the band elimination filter function can be realized through the RC low-pass filter circuit and the RC high-pass filter circuit which are connected in parallel, and the fluctuation of specific frequency on the output voltage sampling circuit can be filtered by adjusting element parameters, so that the input total harmonic current iTHD of the APFC circuit is improved, and the key performance of the active power factor correction circuit is improved.
According to a further scheme, the RC low-pass filter circuit comprises a first resistor, a second resistor, a third resistor and a first capacitor, wherein a first end of the first resistor is connected with an output positive electrode end, a second end of the first resistor is connected with a first end of the second resistor, a first end of the third resistor and a first end of the first capacitor, a second end of the second resistor and a second end of the first capacitor are connected with an output negative electrode end, and a second end of the third resistor is connected with a voltage sampling end.
Furthermore, the voltage division ratio of the RC low-pass filter circuit is m, the first resistor is R1, the second resistor is R2, m is R2/(R1+ R2), and m is larger than or equal to 10.
In a further embodiment, the second resistor is R2, the third resistor is R3, and R2/R3 is between 0.8 and 1.2.
According to a further scheme, the RC high-pass filter circuit comprises a fourth resistor, a second capacitor, a third capacitor and a fourth capacitor, wherein the first end of the second capacitor is connected with the output positive electrode end, the second end of the second capacitor is connected with the first end of the third capacitor, the first end of the fourth capacitor and the first end of the fourth resistor, the second end of the third capacitor and the second end of the fourth resistor are connected with the output negative electrode end, and the second end of the fourth capacitor is connected with the voltage sampling end.
Further, the second capacitor is C2, the third capacitor is C3, the first resistor is R1, the second resistor is R2, and C3/C2 is 0.45-1.6 times of R2/(R1+ R2).
Further, the third capacitor is C3, the fourth capacitor is C4, and C3/C4 is between 0.8 and 1.2.
In a further aspect, the second resistor is R2, the third resistor is R3, and the fourth resistor is R4; r4 is0.45 to 2.2 times; the first capacitor is C1, the third capacitor is C3, and the fourth capacitor is C4; c1 is0.45 to 2.2 times.
Therefore, through the specific circuit device arrangement of the RC low-pass filter circuit and the RC high-pass filter circuit, the combined equivalent diagram is a double-T type second-order wave trap, when the parameters of the elements accord with the setting, the fluctuation of specific frequency in the sampling voltage can be attenuated, the work of the power factor correction circuit is not influenced, and the specific filtering frequency can be adjusted according to the actual product condition through the adjustment of the parameters of the elements.
In order to achieve the second object of the present invention, the present invention provides a switching power supply including the active power factor correction circuit according to the above scheme.
In order to achieve the third object of the present invention, the present invention provides a vehicle including the switching power supply according to the above aspect.
Drawings
Fig. 1 is a circuit diagram of an active power factor correction circuit in the prior art.
Fig. 2 is a circuit diagram of an output voltage sampling circuit in an embodiment of an active power factor correction circuit.
Fig. 3 is an equivalent circuit diagram of an output voltage sampling circuit in an embodiment of an active power factor correction circuit.
Fig. 4 is a bode diagram in an embodiment of an active power factor correction circuit.
The invention is further explained with reference to the drawings and the embodiments.
Detailed Description
Referring to fig. 1 and 2, fig. 2 is a circuit diagram of an output voltage sampling circuit, which is used to replace the voltage sampling circuit 11 in fig. 1, that is, an output positive terminal V + is connected to an output positive terminal Vout, an output negative terminal V-is connected to a ground terminal, a six-port of the power factor correction controller is a voltage sampling terminal Vs, and the power factor correction controller adopts a power factor correction chip of an integrated circuit chip, and of course, chips of different types and different packages have voltage sampling terminals at different positions.
The active power factor correction circuit comprises a power factor correction controller and an output voltage sampling circuit, the active power factor correction circuit is provided with an output positive terminal V + and an output negative terminal V-, the output voltage sampling circuit comprises an RC low-pass filter circuit and an RC high-pass filter circuit which are connected in parallel, the input end of the RC low-pass filter circuit and the input end of the RC high-pass filter circuit are connected with the output positive terminal V +, the grounding end of the RC low-pass filter circuit and the grounding end of the RC high-pass filter circuit are connected with the output negative terminal V-, and the output end of the RC low-pass filter circuit and the output end of the RC high-pass filter circuit are connected with a voltage sampling terminal Vs.
Specifically, the RC low-pass filter circuit comprises a first resistor R1, a second resistor R2, a third resistor R3 and a first capacitor C1, wherein a first end of the first resistor R1 is connected with the output positive terminal V +, a second end of the first resistor R1 is connected with a first end of the second resistor R2, a first end of the third resistor R3 and a first end of the first capacitor C1, a second end of the second resistor R2 and a second end of the first capacitor C1 are connected with the output negative terminal V-, and a second end of the third resistor R3 is connected with the voltage sampling terminal Vs.
The RC high-pass filter circuit comprises a fourth resistor R4, a second capacitor C2, a third capacitor C3 and a fourth capacitor C4, wherein the first end of the second capacitor C2 is connected with an output positive electrode end V +, the second end of the second capacitor C2 is connected with the first end of the third capacitor C3, the first end of the fourth capacitor C4 and the first end of the fourth resistor R4, the second end of the third capacitor C3 and the second end of the fourth resistor R4 are connected with an output negative electrode end V-, and the second end of the fourth capacitor C4 is connected with a voltage sampling end Vs.
The voltage division ratio of the RC low-pass filter circuit is defined as m, m is R2/(R1+ R2), when the voltage division ratio m is greater than 10, and C3/C2 is approximately equal to the voltage division ratio m, and R2 and R3 are approximately equal, and C3 and C4 are approximately equal, it can be approximately reduced to an equivalent diagram as shown in fig. 3, in which the parameter relationship is: ve ═ V +/m, C ═ C3 ═ C4, R ═ R2 ═ R3, the equivalent diagram is a typical double-T type second order trap, and when its parameters satisfy a specific relationship, the fluctuation of a specific frequency in the Vs sampling voltage is attenuated without affecting the operation of the APFC circuit.
The specific relationship is as follows:
the R4 parameter is k times R;
the C1 parameter is 1/k times of C;
the angular frequency corresponding to RC is equal to 2 times of the AC input angular frequency of the APFC circuit;
at this time, the transfer function of the second order system is:
when the parameters satisfy all the above conditions, and k is selected to be 1, the voltage sampling circuit can attenuate the voltage fluctuation of a specific frequency by about 12dB, and the phase shift at 1/10 filtering center frequency is about 15.4 degrees.
In practical engineering applications, the parameters of the electronic components are limited, so that the electronic components may adopt the following parameters:
1. the partial pressure ratio m is more than or equal to 10;
2. C3/C2 is 0.45 to 1.6 times m;
3. R2/R3 is between 0.8 and 1.2;
4. C3/C4 is between 0.8 and 1.2;
By filtering the specific frequency by the output voltage sampling circuit of the scheme, referring to fig. 4, fig. 4 is a bode diagram of the active power factor correction circuit, Y1 is a phase-frequency characteristic curve, and Y2 is an amplitude-frequency characteristic curve, the scheme can provide attenuation of about 10dB at the specific frequency of about 200 Hz.
The switching power supply comprises the active power factor correction circuit of the scheme, and can be a charger, a power supply, a motor controller and the like.
The vehicle comprises the switching power supply, and can be a new energy electric car, a new energy electric passenger car, a new energy electric truck, a new energy electric cleaning vehicle, a new energy electric rail vehicle, a new energy electric flying vehicle, a new energy electric shipping vehicle and the like.
The above embodiments are preferred embodiments of the present disclosure, and may have more variations in specific applications, for example, for the above voltage sampling circuit, each circuit element is equivalent, for each resistor or capacitor in the figure, a plurality of elements can be connected in series and in parallel to obtain the same equivalent parameters, which should be regarded as the same inventive concept, and the external connection modes of V +, V-, and three terminals Vs have various types, in addition, a resistor Rs may be connected in series to the capacitor C1, when the ratio of Rs/R2 is far smaller than the voltage division ratio m, the circuit can still obtain beneficial effects, and the above variations all fall within the protection scope of the present disclosure.
Therefore, through the specific circuit device arrangement of the RC low-pass filter circuit and the RC high-pass filter circuit, the combined equivalent diagram is a double-T type second-order wave trap, when the parameters of the elements accord with the setting, the fluctuation of specific frequency in the sampling voltage can be attenuated, the work of the power factor correction circuit is not influenced, and the specific filtering frequency can be adjusted according to the actual product condition through the adjustment of the parameters of the elements.
Claims (10)
1. The active power factor correction circuit comprises a power factor correction controller and an output voltage sampling circuit, wherein the active power factor correction circuit is provided with an output positive terminal and an output negative terminal, and the power factor correction controller is provided with a voltage sampling terminal;
the method is characterized in that:
the output voltage sampling circuit comprises an RC low-pass filter circuit and an RC high-pass filter circuit which are connected in parallel, the input end of the RC low-pass filter circuit and the input end of the RC high-pass filter circuit are connected with the output positive electrode end, the grounding end of the RC low-pass filter circuit and the grounding end of the RC high-pass filter circuit are connected with the output negative electrode end, and the output end of the RC low-pass filter circuit and the output end of the RC high-pass filter circuit are connected with the voltage sampling end.
2. The active power factor correction circuit of claim 1, wherein:
the RC low-pass filter circuit comprises a first resistor, a second resistor, a third resistor and a first capacitor, wherein the first end of the first resistor is connected with the positive output end, the second end of the first resistor is connected with the first end of the second resistor, the first end of the third resistor and the first end of the first capacitor, the second end of the second resistor, the second end of the first capacitor and the negative output end are connected, and the second end of the third resistor is connected with the voltage sampling end.
3. The active power factor correction circuit of claim 2, wherein:
the voltage division ratio of the RC low-pass filter circuit is m, the first resistor is R1, the second resistor is R2, m is R2/(R1+ R2), and m is larger than or equal to 10.
4. The active power factor correction circuit of claim 2, wherein:
the second resistor is R2, the third resistor is R3, and R2/R3 is between 0.8 and 1.2.
5. The active power factor correction circuit of any of claims 2 to 4, wherein:
the RC high-pass filter circuit comprises a fourth resistor, a second capacitor, a third capacitor and a fourth capacitor, wherein the first end of the second capacitor is connected with the positive output terminal, the second end of the second capacitor is connected with the first end of the third capacitor, the first end of the fourth capacitor and the first end of the fourth resistor, the second end of the third capacitor and the second end of the fourth resistor are connected with the negative output terminal, and the second end of the fourth capacitor is connected with the voltage sampling terminal.
6. The active power factor correction circuit of claim 5, wherein:
the second capacitor is C2, the third capacitor is C3, the first resistor is R1, the second resistor is R2, and C3/C2 is 0.45-1.6 times of R2/(R1+ R2).
7. The active power factor correction circuit of claim 5, wherein:
the third capacitor is C3, the fourth capacitor is C4, and C3/C4 is between 0.8 and 1.2.
9. Switching power supply, characterized in that it comprises an active power factor correction circuit according to any of the claims 1 to 8.
10. Vehicle, characterized in that it comprises a switched-mode power supply according to claim 9.
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CN114142718B CN114142718B (en) | 2023-05-09 |
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Citations (9)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
DE3304776A1 (en) * | 1983-02-11 | 1984-08-16 | Richard Hirschmann Radiotechnisches Werk, 7300 Esslingen | Band-stop filter |
JP2008125312A (en) * | 2006-11-15 | 2008-05-29 | Sakae Shibazaki | Switching power supply |
CN101542925A (en) * | 2007-01-19 | 2009-09-23 | 株式会社村田制作所 | High frequency part |
TW201035717A (en) * | 2009-03-30 | 2010-10-01 | Rhymebus Corp | Power factor correction converter with fast loading regulation capability |
CN202330535U (en) * | 2011-11-16 | 2012-07-11 | 临汾电力高级技工学校 | Insulating bar type non-contact electricity testing alarm |
CN105253299A (en) * | 2015-09-07 | 2016-01-20 | 西安航空制动科技有限公司 | Antiskid brake control method suitable for undercarriage characteristic frequency |
CN206077667U (en) * | 2016-08-18 | 2017-04-05 | 重庆蓝岸通讯技术有限公司 | Reduce the circuit of microphone audio noise |
CN107611973A (en) * | 2017-09-30 | 2018-01-19 | 国网浙江嵊州市供电有限公司 | Notch filter for distributed power supply system |
CN211127565U (en) * | 2019-10-24 | 2020-07-28 | 常州工学院 | Special power filter for EMI alternating current medical equipment |
-
2021
- 2021-11-18 CN CN202111374012.7A patent/CN114142718B/en active Active
Patent Citations (9)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
DE3304776A1 (en) * | 1983-02-11 | 1984-08-16 | Richard Hirschmann Radiotechnisches Werk, 7300 Esslingen | Band-stop filter |
JP2008125312A (en) * | 2006-11-15 | 2008-05-29 | Sakae Shibazaki | Switching power supply |
CN101542925A (en) * | 2007-01-19 | 2009-09-23 | 株式会社村田制作所 | High frequency part |
TW201035717A (en) * | 2009-03-30 | 2010-10-01 | Rhymebus Corp | Power factor correction converter with fast loading regulation capability |
CN202330535U (en) * | 2011-11-16 | 2012-07-11 | 临汾电力高级技工学校 | Insulating bar type non-contact electricity testing alarm |
CN105253299A (en) * | 2015-09-07 | 2016-01-20 | 西安航空制动科技有限公司 | Antiskid brake control method suitable for undercarriage characteristic frequency |
CN206077667U (en) * | 2016-08-18 | 2017-04-05 | 重庆蓝岸通讯技术有限公司 | Reduce the circuit of microphone audio noise |
CN107611973A (en) * | 2017-09-30 | 2018-01-19 | 国网浙江嵊州市供电有限公司 | Notch filter for distributed power supply system |
CN211127565U (en) * | 2019-10-24 | 2020-07-28 | 常州工学院 | Special power filter for EMI alternating current medical equipment |
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