CN102364814A - Active PFC (Power Factor Controller) control method of direct-current frequency-conversion air conditioner - Google Patents
Active PFC (Power Factor Controller) control method of direct-current frequency-conversion air conditioner Download PDFInfo
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- CN102364814A CN102364814A CN2011103133745A CN201110313374A CN102364814A CN 102364814 A CN102364814 A CN 102364814A CN 2011103133745 A CN2011103133745 A CN 2011103133745A CN 201110313374 A CN201110313374 A CN 201110313374A CN 102364814 A CN102364814 A CN 102364814A
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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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Abstract
The invention belongs to the technical field of frequency-conversion air conditioner control, and in particular relates to an active PFC (Power Factor Controller) control method of a direct-current frequency-conversion air conditioner. In a control system, a DSP (Digital Signal processor) main controller for controlling a PFC device is comprised, wherein the DSP main controller is provided with a PFC control algorithm program module. The active PFC control method of the air conditioner comprises the step of: setting different target busbar voltages V'dc for the PFC control algorithm program module according to the alternating-current input voltage of the air conditioner and the operation frequency of a frequency-conversion compressor to realize seamless switchover between a partially active PFC and a completely active PFC. The control method provided by the invention has the capabilities of reducing IGBT (Insulated Gate Bipolar Transistor) loss of a PFC circuit to the greatest degree and fully meeting requirements of high-frequency heavy-load operation of the frequency-conversion air conditioner and has the advantages of both the partially active PFC and the completely active PFC.
Description
Technical field
The invention belongs to convertible frequency air-conditioner control technology field, particularly relate to the active PFC control method of a kind of direct current varied-frequency air conditioner.
Background technology
PFC, English full name are Power Factor Corrector, i.e. power factor corrector, and it can improve the utilance of power supply to civil power when interchange converts direct current into, reduce the electric energy loss of transfer process, reaches purpose of energy saving.Air-conditioning is as the big power consumer in the household electrical appliance, and power supply seems particularly important to the service efficiency of civil power, so PFC is one of device commonly used in the DC frequency converting air-conditioner.
PFC has two kinds, and a kind of is passive PFC, and a kind of is active PFC.Passive PFC generally adopts the inductance compensation method, through reducing to exchange the fundamental current of input and the phase difference between the voltage improves power factor.Active PFC generally is made up of inductance, IGBT, MCU or electronic devices and components such as DSP, diode.The power factor of passive PFC is not very high, can only reach 0.7～0.8; Active PFC can reach very high power factor, generally can reach 0.99, and volume is little, but cost is higher.
Active PFC according to control assembly output the control wave difference be divided into two big types of the active PFC of part and complete active PFC; The characteristics of the active PFC of part are that the copped wave control signal that master controller is exported to execution unit IGBT in each input voltage cycle is discontinuous, and the characteristics of complete active PFC are that the copped wave control signal that master controller is exported to execution unit IGBT in each input voltage cycle is continuous.
Advantages such as it is little that the active PFC device of part possesses the IGBT loss, and it is low to generate heat, but the effect of boosting of output voltage is limited are used in that compressor can not move very high-frequency on the convertible frequency air-conditioner product; Complete active PFC device possesses the advantage such as effective of boosting, but the IGBT loss is big, and heating is serious, and being used in needs very big IGBT radiator on the convertible frequency air-conditioner product.Active PFC device of part and complete active PFC device all have a large amount of uses on DC frequency converting air-conditioner at present.
PFC device in the existing DC frequency converting air-conditioner product only finds to use separately the product of active PFC of part or complete active PFC because the reason of control method or cost, finds to exist simultaneously the product of active PFC of part and complete active PFC as yet.
Summary of the invention
The technical problem that the present invention will solve be overcome the deficiency of prior art and provide a kind of can the active PFC of implementation part and complete active PFC between the active PFC control method of direct current varied-frequency air conditioner of seamless switching.
For solving the problems of the technologies described above; Scheme of the present invention is: the active PFC control method of a kind of direct current varied-frequency air conditioner; Comprise the DSP master controller that is used to control the PFC device in control system; The DSP master controller is provided with PFC control algolithm program module, and the active PFC control method of said air conditioner is to give PFC control algolithm module settings different target busbar voltage V' according to the AC-input voltage of air conditioner and frequency-changeable compressor running frequency
Dc, seamless switching between active PFC of implementation part and the complete active PFC comprises the steps:
Step 1:DSP master controller samples alternating voltage instantaneous value
through the input voltage sample circuit of air conditioner, calculates the effective value Vrms of AC-input voltage through formula Vrms=
;
The voltage effective value Vrms that step 2:DSP master controller calculates according to the given back electromotive-force constant Ke of frequency-changeable compressor and step 1 is through formula F remax=(
* Vrms)/Ke calculates the PFC device and is operated in the highest frequency Fremax that the situation down-conversion compressor that do not boost can reach;
Step 3:DSP master controller calculates the current running frequency FreRun of frequency-changeable compressor through the load current sample circuit, carries out like the calculating that judges with the Freqmax that step 2 calculates then:
Work as FreRun<freqmax gives the busbar voltage V' that sets the goal
Dc=
* Vrms – a
1
As FreRun>=Freqmax, give the busbar voltage V' that sets the goal
Dc=FreRun * Ke+a
2
DSP realizes actual dc busbar voltage V through PFC control algolithm program module
DcFinally infinitely near target busbar voltage V'
Dc
A wherein
1, a
2Be target busbar voltage corrected parameter, its span is 10≤a
1≤20,0≤a
2≤20.
In the such scheme, as target busbar voltage V'
Dc<
* during Vrms, the PFC device is operated in the active PFC state of part; As target busbar voltage V'
Dc>=
* during Vrms, the PFC device is operated in complete active PFC state.
Compared with prior art, the present invention with respect to the beneficial effect of prior art is:
The control method of the active PFC of direct current varied-frequency air conditioner of the present invention can the active PFC of implementation part and complete active PFC between seamless switching; Can at utmost reduce the IGBT loss of pfc circuit; Can fully satisfy the demand of convertible frequency air-conditioner high frequency heavy service again, have both the advantage of active PFC of part and complete active PFC.
Description of drawings
Below in conjunction with accompanying drawing and embodiment the present invention is done further detailed explanation.
Fig. 1 is the automatically controlled structure chart one of DC frequency converting air-conditioner off-premises station that has source PFC device;
Fig. 2 is the automatically controlled structure chart two of DC frequency converting air-conditioner off-premises station that has source PFC device;
Fig. 3 is the active PFC control method of a direct current varied-frequency air conditioner flow chart.
Embodiment
Like Fig. 1 or shown in Figure 2, have the automatically controlled structure of DC frequency converting air-conditioner off-premises station of source PFC device: parts 1 are the mains ac power supply input, and parts 2 are the rectification unit circuit; Parts 3 are the PFC inductance, and parts 4 are the input voltage sample circuit, and parts 5 are the load current sample resistance; Parts 6 are the PFC current sampling circuit, and parts 7 are the IGBT drive circuit, and parts 8 are IGBT and fly-wheel diode device; Parts 9 are fast recovery diode, and parts 10 are energy storage filter unit circuit, and parts 11 are the PFC output voltage sampling circuit; Parts 12 are load driving circuits, and parts 13 are frequency-changeable compressor, dc fan even load, and parts 14 are the load current sample resistance; Parts 15 are the load current sample circuit, and parts 16 are the DSP master controller.Wherein, parts 3, parts 4, parts 5, parts 6, parts 7, parts 8, parts 9, parts 11 and parts 13 have constituted complete active PFC device according to the order of connection of Fig. 1 or Fig. 2.
The characteristics of Fig. 1 are that the alternating voltage sampling is taken a sample from rectification unit circuit (being parts 2) input; The advantage of this circuit is that ac voltage signal is not influenced by other components and parts; Signal is clean, and shortcoming is the problem that master control DSP will consider the alternating voltage midpoint potential, and sample range is influenced.
The characteristics of Fig. 2 are that the alternating voltage sampling is taken a sample from rectification unit circuit (being parts 2) output; The advantage of this circuit is that the ground of alternating voltage sample circuit and the ground of chip operation power supply are equipotential; The circuit structure of relative Fig. 1; The alternating voltage sample range of master control DSP has enlarged one times, or resolution is doubled under the prerequisite of equal voltage sample scope, and shortcoming is the influence that ac voltage signal receives PFC inductance (parts 3) easily.
Fig. 1 is the automatically controlled structure of DC frequency converting air-conditioner off-premises station that has source PFC relatively more commonly used, and the automatically controlled structure of Fig. 2 is seldom used in product greatly because of PFC control difficulty, and active PFC control method of the present invention all is suitable on two kinds of Circuits System of Fig. 1 and Fig. 2.
The PFC digital control algorithm has mainly comprised two control loops: Voltage loop and electric current loop, Voltage loop is controlled dc bus voltage V through regulating average current input
Dc, current loop control exchanges input current and makes it to follow the tracks of AC-input voltage.The control algolithm of PFC is to realize that in DSP lining program module for convenience, we are referred to as PFC control algolithm program module.To be DSP sample AC-input voltage signal, parts 6 through parts 4 to main thought samples PFC current signal, parts 11 and sample DC bus-bar voltage and programmer according to the given dc bus target voltage V' of different condition
Dc, the duty ratio through certain algorithm is regulated the pwm control signal of exporting to parts 7 finally reaches actual dc busbar voltage V
DcInfinitely near target voltage V'
DcPurpose.
As shown in Figure 3, the active PFC control method of air conditioner of the present invention is to give PFC control algolithm module settings different target busbar voltage V' according to AC-input voltage and compressor operating frequency
Dc, seamless switching between active PFC of implementation part and the complete active PFC specifically comprises the steps:
Step 1:DSP master controller samples alternating voltage instantaneous value
through the input voltage sample circuit of air conditioner, calculates the effective value Vrms of AC-input voltage through formula Vrms=
;
The voltage effective value Vrms that step 2:DSP master controller calculates according to the given back electromotive-force constant Ke of frequency-changeable compressor and step 1 is through formula F remax=(
* Vrms)/Ke calculates the PFC device and is operated in the highest frequency Fremax that the situation down-conversion compressor that do not boost can reach;
Step 3:DSP master controller calculates the current running frequency FreRun of frequency-changeable compressor through the load current sample circuit, carries out like the calculating that judges with the Freqmax that step 2 calculates then:
Work as FreRun<freqmax gives the busbar voltage V' that sets the goal
Dc=
* Vrms – a
1
As FreRun>=Freqmax, give the busbar voltage V' that sets the goal
Dc=FreRun * Ke+a
2
DSP realizes actual dc busbar voltage V through PFC control algolithm program module
DcFinally infinitely near target busbar voltage V'
Dc
A wherein
1, a
2Be target busbar voltage corrected parameter, its span is 10≤a
1≤20,0≤a
2≤20.
As target busbar voltage V'
Dc<
* during Vrms, the PFC device is operated in the active PFC state of part; As target busbar voltage V'
Dc>=
* during Vrms, the PFC device is operated in complete active PFC state.
Claims (2)
1. active PFC control method of direct current varied-frequency air conditioner; It is characterized in that: comprise the DSP master controller that is used to control the PFC device in control system; The DSP master controller is provided with PFC control algolithm program module, and the active PFC control method of said air conditioner is to give PFC control algolithm module settings different target busbar voltage V' according to the AC-input voltage of air conditioner and frequency-changeable compressor running frequency
Dc, seamless switching between active PFC of implementation part and the complete active PFC comprises the steps:
Step 1:DSP master controller samples alternating voltage instantaneous value
through the input voltage sample circuit of air conditioner, calculates the effective value Vrms of AC-input voltage through formula Vrms=
;
The voltage effective value Vrms that step 2:DSP master controller calculates according to the given back electromotive-force constant Ke of frequency-changeable compressor and step 1 is through formula F remax=(
* Vrms)/Ke calculates the PFC device and is operated in the highest frequency Fremax that the situation down-conversion compressor that do not boost can reach;
Step 3:DSP master controller calculates the current running frequency FreRun of frequency-changeable compressor through the load current sample circuit, carries out like the calculating that judges with the Freqmax that step 2 calculates then:
Work as FreRun<freqmax gives the busbar voltage V' that sets the goal
Dc=
* Vrms – a
1
As FreRun>=Freqmax, give the busbar voltage V' that sets the goal
Dc=FreRun * Ke+a
2
DSP realizes actual dc busbar voltage V through PFC control algolithm program module
DcFinally infinitely near target busbar voltage V'
Dc
A wherein
1, a
2Be target busbar voltage corrected parameter.
2. the active PFC control method of direct current varied-frequency air conditioner according to claim 1 is characterized in that: based on working as target busbar voltage V'
Dc<
* during Vrms, the PFC device is operated in the active PFC state of part; As target busbar voltage V'
Dc>=
* during Vrms, the PFC device is operated in the principle of complete active PFC state, and target busbar voltage corrected parameter span is 10≤a
1≤20,0≤a
2≤20.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201110313374.5A CN102364814B (en) | 2011-10-17 | A kind of direct current varied-frequency air conditioner active PFC control method |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201110313374.5A CN102364814B (en) | 2011-10-17 | A kind of direct current varied-frequency air conditioner active PFC control method |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN102364814A true CN102364814A (en) | 2012-02-29 |
| CN102364814B CN102364814B (en) | 2016-12-14 |
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Cited By (12)
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|---|---|---|---|---|
| CN103427619A (en) * | 2012-05-24 | 2013-12-04 | 珠海格力电器股份有限公司 | PFC control circuit capable of boosting flexibly and control method thereof |
| CN104214886B (en) * | 2013-05-30 | 2017-03-29 | 广东美的制冷设备有限公司 | The control method of convertible frequency air-conditioner |
| WO2017181076A1 (en) | 2016-04-15 | 2017-10-19 | Emerson Electric Co. | Power factor correction circuits and methods including partial power factor correction operation for boost and buck power converters |
| CN107370404A (en) * | 2017-08-09 | 2017-11-21 | 航天长峰朝阳电源有限公司 | Integrated PFC high voltage half-bridge resonance synchronous rectification AC/DC power modules |
| CN107388661A (en) * | 2017-07-27 | 2017-11-24 | 广东美的制冷设备有限公司 | Solar air-conditioner system and its Poewr control method and device |
| CN107830571A (en) * | 2017-10-17 | 2018-03-23 | 广东美的制冷设备有限公司 | Transducer air conditioning |
| CN108631627A (en) * | 2018-06-04 | 2018-10-09 | 广东美的制冷设备有限公司 | rectification control method, air conditioner and computer readable storage medium |
| CN109861198A (en) * | 2019-03-08 | 2019-06-07 | 广东美的制冷设备有限公司 | Fan power circuit, fan assembly and air conditioner |
| CN111256281A (en) * | 2018-11-30 | 2020-06-09 | 广东美的制冷设备有限公司 | Operation control method and system, compressor and air conditioner |
| US10763740B2 (en) | 2016-04-15 | 2020-09-01 | Emerson Climate Technologies, Inc. | Switch off time control systems and methods |
| US10928884B2 (en) | 2016-04-15 | 2021-02-23 | Emerson Climate Technologies, Inc. | Microcontroller architecture for power factor correction converter |
| CN114322227A (en) * | 2021-12-30 | 2022-04-12 | 海信（山东）空调有限公司 | Compressor control method and device, household appliance and storage medium |
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Cited By (16)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103427619B (en) * | 2012-05-24 | 2015-09-16 | 珠海格力电器股份有限公司 | PFC control circuit capable of boosting flexibly and control method thereof |
| CN103427619A (en) * | 2012-05-24 | 2013-12-04 | 珠海格力电器股份有限公司 | PFC control circuit capable of boosting flexibly and control method thereof |
| CN104214886B (en) * | 2013-05-30 | 2017-03-29 | 广东美的制冷设备有限公司 | The control method of convertible frequency air-conditioner |
| EP3443656A4 (en) * | 2016-04-15 | 2019-12-25 | Emerson Climate Technologies, Inc. | Power factor correction circuits and methods including partial power factor correction operation for boost and buck power converters |
| WO2017181076A1 (en) | 2016-04-15 | 2017-10-19 | Emerson Electric Co. | Power factor correction circuits and methods including partial power factor correction operation for boost and buck power converters |
| US11387729B2 (en) | 2016-04-15 | 2022-07-12 | Emerson Climate Technologies, Inc. | Buck-converter-based drive circuits for driving motors of compressors and condenser fans |
| US10928884B2 (en) | 2016-04-15 | 2021-02-23 | Emerson Climate Technologies, Inc. | Microcontroller architecture for power factor correction converter |
| US10763740B2 (en) | 2016-04-15 | 2020-09-01 | Emerson Climate Technologies, Inc. | Switch off time control systems and methods |
| CN107388661A (en) * | 2017-07-27 | 2017-11-24 | 广东美的制冷设备有限公司 | Solar air-conditioner system and its Poewr control method and device |
| CN107370404A (en) * | 2017-08-09 | 2017-11-21 | 航天长峰朝阳电源有限公司 | Integrated PFC high voltage half-bridge resonance synchronous rectification AC/DC power modules |
| CN107830571A (en) * | 2017-10-17 | 2018-03-23 | 广东美的制冷设备有限公司 | Transducer air conditioning |
| CN108631627A (en) * | 2018-06-04 | 2018-10-09 | 广东美的制冷设备有限公司 | rectification control method, air conditioner and computer readable storage medium |
| CN111256281A (en) * | 2018-11-30 | 2020-06-09 | 广东美的制冷设备有限公司 | Operation control method and system, compressor and air conditioner |
| CN109861198A (en) * | 2019-03-08 | 2019-06-07 | 广东美的制冷设备有限公司 | Fan power circuit, fan assembly and air conditioner |
| CN114322227A (en) * | 2021-12-30 | 2022-04-12 | 海信（山东）空调有限公司 | Compressor control method and device, household appliance and storage medium |
| CN114322227B (en) * | 2021-12-30 | 2023-09-15 | 海信空调有限公司 | Control method and device of compressor, household appliance and storage medium |
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Owner name: MIDEA GROUP CO., LTD. Free format text: FORMER OWNER: MEIDI ELECTRIC APPLIANCES CO., LTD., GUANGDONG Effective date: 20131211 |
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Effective date of registration: 20131211 Address after: 528311 Guangdong, Foshan, Beijiao, the United States, the United States and the United States on the avenue of the United States, the headquarters of the United States building B floor, District, 26-28 Applicant after: Midea Group Co., Ltd. Address before: 528311 beautiful road, Beijiao Town, Shunde District, Guangdong, Foshan Applicant before: Meidi Electric Appliances Co., Ltd., Guangdong |
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Inventor after: Qiu Xiangwei Inventor after: Zhu Lianghong Inventor after: Zhang Wenkai Inventor after: Fu Xin Inventor after: Luo Yuhua Inventor before: Zhu Lianghong Inventor before: Zhang Wenkai Inventor before: Fu Xin Inventor before: Luo Yuhua |
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