CN101237185A - Energy feedback and harmonic wave passive compensation system applicable to commutation device - Google Patents
Energy feedback and harmonic wave passive compensation system applicable to commutation device Download PDFInfo
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- CN101237185A CN101237185A CNA2007101686653A CN200710168665A CN101237185A CN 101237185 A CN101237185 A CN 101237185A CN A2007101686653 A CNA2007101686653 A CN A2007101686653A CN 200710168665 A CN200710168665 A CN 200710168665A CN 101237185 A CN101237185 A CN 101237185A
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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
- Y02E40/30—Reactive power compensation
Abstract
The invention discloses an energy feedback and harmonic passive power compensation system applicable to a rectifying device, comprising a power transistor, a controlling device, a three-phase power bridge and a filtering device, wherein, the anode of the power transistor is connected with the anode of a diode rectifying DC voltage, and the cathode of the power transistor is connected with the anode of a DC bus voltage of the three-phase power bridge; the cathode of a diode rectifying DC bus voltage is connected with the cathode of a DC voltage of the three-phase power bridge; the controlling device is used to control the opening and cutting of a power transistor of the three-phase power bridge; the three-phase power bridge is used to provide DC bus voltage to the controlling device and control the closing of the power transistor according to a command from the controlling device to generate a compensation current and provides the compensation current to the filtering device; the filtering device receives the compensation current from the three-phase power bridge, compensates the compensation current to the power grid after filtering high harmonics and provides the current signals to the controlling device. The energy feedback and harmonic reactive power compensation system can play the roles of active filtering and passive compensation, feed back energy to the power grid and realize energy saving.
Description
Technical field
The technology of the present invention relates to electrotechnical, electronic and Electric Drive technical field, is specifically related to a kind of energy feedback and harmonic reactive-load compensation system that is applicable to rectifying device.
Background technology
In the electrical and electronic technology field, diode rectifier circuit is simple, economic and reliable, thereby is widely used in present most power electronics and power transmission system; But the rectifier of this diode rectifier circuit is extensive use of, and has also brought the problem of following following several aspects:
With reference to " power electronic technology " that China Machine Press publishes, mention the following shortcoming of diode rectification in the book:
1. diode rectification can make the current on line side waveform seriously distort, and causes power factor lower, and highest power factor is only about 0.8; The consumption of a large amount of reactive powers brings extra burden to electrical network, has increased the loss of transmission line, and has seriously influenced the power supply quality of whole electrical network, needs to adopt necessary reactive power compensation to change this situation.
2. carry out spectrum analysis at the input current to diode rectifier, find to contain profuse low-order harmonic electric current in the input current, this low-order harmonic electric current impairs power supply quality, must carry out necessary harmonic wave control.
3. can obtain good filter effect if use the pwm rectification instead, but its shortcoming is as follows: 1) adopt in present most of system for can not commutation system, if substitute the uncontrollable rectification of diode with controlled PWM rectification on a large scale, this way is unrealistic in actual applications; 2) in powerful Circuits System, if replace diode rectification with controlled PWM rectification fully, then the power switch pipe of full control needs very big capacity, cost is very high, and implement very difficult, so this method by controlled PWM rectification solves the existing problem of diode rectification system, does not also have practical significance comprehensively.
If in AC variable-frequency speed regulation system, adopt this diode rectification technology, because the unilateal conduction performance of diode, then the regenerated energy in the motor braking process can't feed back to electrical network, actual Alternating Current Governor System is in order to make each device safe operation, and this part energy also must consume it by certain approach; Thereby in system the general dynamic braking mode that adopts, promptly by the built-in or method that adds brake resistance with power consumption in Power Resistor, thereby realize the four-quadrant safe operation of motor.Though this method is simple, has following shortcoming:: 1) a large amount of electric energy are consumed in vain, and running efficiency of system is low; 2) resistance heating is serious, and heat radiation is a big problem, has a strong impact on other part operate as normal of system; 3) simple dynamic braking can not in time suppress fast braking and the pump up voltage that produces, is unfavorable for the further raising of overall system performance.
Chinese patent literature CN1274977A discloses a kind of the combined power filter with both of passive formation " active and " on November 29th, 2000, this device utilizes active power filtering and passive filtering to carry out harmonic compensation, but can not carry out feedback, and complex structure to the energy in the electrical network.
Summary of the invention
The object of the present invention is to provide a kind of energy feedback and harmonic reactive-load compensation system that is applicable to rectifying device, this system is good wave filtering effect not only, and cost is lower, and can give electrical network with the Way of Regenerating Energy Feedback in the motor braking process.
Energy feedback and the harmonic reactive-load compensation system that is applicable to rectifying device provided by the invention is characterized in that: this system comprises power switch pipe, control device, power three-phase bridge and filter;
The positive pole of power switch pipe connects the DC bus-bar voltage output of uncontrollable diode rectification device, and its negative pole connects the DC bus-bar voltage positive pole of power three-phase bridge; The DC bus-bar voltage cathode output end of power three-phase bridge links to each other with the DC bus-bar voltage cathode output end of uncontrollable diode rectification device;
Control device is used to obtain the input load electric current of uncontrollable diode rectification device, the offset current of filter output and the DC bus-bar voltage of power three-phase bridge, according to the parameter generating switching signal of obtaining, the power switch pipe of power controlling three-phase bridge opening and turn-offing respectively;
The power three-phase bridge is used for providing DC bus-bar voltage to control device, and the closure of the commands for controlling power switch pipe that provides according to control device produces offset current, and offers filter;
Filter is accepted the offset current from the power three-phase bridge, leaches high order harmonic component, offset current is compensated into electrical network, and this current signal is offered control device.
Before not adopting system of the present invention, the harmonic content THD of former external circuit system is very high, and power factor (PF) is not high yet, and after adding system of the present invention, the harmonic content THD of former external circuit system can drop to very low, and power factor (PF) can rise near 1.And capacity usage ratio significantly improves.Particularly, the present invention has following characteristics:
(1) need not change the circuit structure and the connected mode of current uncontrollable diode rectification system and electrical network etc.; With respect to adopting the PWM rectification that the system of DC power supply is provided, the capacity of this case system and controllable function pipe can reduce greatly, has reduced system cost, has increased the realizability and the reliability of system;
(2) can realize that this case system and former diode rectification system can not inject harmonic wave and idle to electrical network in running, eliminate pollution electrical network;
(3) when motor braking, the unnecessary electric energy of former diode rectification system flows to electrical network by this case device.Can realize the energy feedback, play purpose of energy saving, good economic benefit and social benefit are arranged;
The function of (4) system capacity feedback, active power filtering and reactive power compensation can be integrated on the device and realize by adopting the control corresponding method, is an incorporate system.
Description of drawings
Fig. 1 is the structured flowchart of energy feedback of the present invention and harmonic reactive-load compensation system; Wherein 1 for system of the present invention, and 2 is former external circuit system;
The workflow diagram of Fig. 2 control device, control device adopt two closed-loop controls, a) are the outer voltage workflow, b) are the current inner loop workflow;
Fig. 3 is the example circuit diagram of energy feedback of the present invention and harmonic reactive-load compensation system.
Embodiment
Below in conjunction with accompanying drawing system of the present invention is described in further detail.
The rectifying device that system of the present invention was suitable for is linked to each other in proper order by electrical network 3, uncontrollable diode rectification device frequency converter 5 and load 6 one-level one-levels.
As shown in Figure 1, energy feedback of the present invention and harmonic reactive-load compensation system comprise power switch pipe 7, control device 8, power three-phase bridge 9 and filter 10.Diode rectification DC bus-bar voltage cathode output end links to each other with this case system DC bus-bar voltage cathode output end.
The positive pole of power switch pipe 7 connects the DC bus-bar voltage cathode output end of uncontrollable diode rectification device 4, its negative pole connects the DC bus-bar voltage positive pole of power three-phase bridge 9, when the DC bus-bar voltage that the uncontrollable diode rectification device 4 that receives when power switch pipe 7 provides is higher than the DC bus-bar voltage of power three-phase bridge 9, power switch pipe 7 conductings, the DC bus-bar voltage of power three-phase bridge 9 is drawn high, size is the DC bus-bar voltage that uncontrollable diode rectification device 4 provides, and is higher than the given voltage of this case system; When the DC bus-bar voltage that the uncontrollable diode rectification device 4 that receives when power switch pipe 7 provides is not higher than the DC bus-bar voltage of power three-phase bridge 9, power switch pipe 7 not conductings, the DC bus-bar voltage of power three-phase bridge 9 is maintained given voltage swing.
Power three-phase bridge 9 provides DC bus-bar voltage to control device 8, and accepts the control of control device 8 to its power switch pipe, flows to electrical network thereby produce offset current by filter 10.When the DC bus-bar voltage of power three-phase bridge 9 is lower than the DC bus-bar voltage of uncontrollable diode rectification device 4, power switch pipe 7 conductings are added to the DC bus-bar voltage of diode rectification device 4 dc terminal of power three-phase bridge 9, when the DC bus-bar voltage of power three-phase bridge 9 was not less than the DC bus-bar voltage of uncontrollable diode rectification device 4, the control action by control device 8 absorbs energy by filter 10 from electrical network 3 made the DC bus-bar voltage of power three-phase bridge 9 be maintained the given magnitude of voltage of system.
The offset current that filter 10 is accepted from the power three-phase bridge leaches high order harmonic component post-compensation current compensation and goes into electrical network 3, reduces the pollution of high order harmonic component to electrical network.
Fig. 3 is that Fig. 1 is the example circuit diagram of energy feedback of the present invention and harmonic reactive-load compensation system, the present invention is described in detail below by Fig. 3 again.
This example is based on energy feedback and the harmonic reactive-load compensation system example of DSP.That this example power switch pipe 7 is selected for use is diode D7; Power three-phase bridge 9 adopts the three-phase half-bridge structure; For the effective filtering high order harmonic component relevant with switching frequency, bank of filters 10 is taked the filter construction be made up of inductance; Control device 8 is made up of current sensor 8.1, voltage sensor 8.2 and controlling and driving plate 8.3, and controlling and driving plate 8.3 adopts DSP to realize.Load is a motor.
The positive pole of diode D7 is connected on the positive pole of the DC side electric capacity of voltage regulation C1 of uncontrollable diode rectification device, and the negative pole of diode D7 is connected on the positive pole of the electric capacity of voltage regulation C2 of power three-phase bridge DC side.The dc bus capacitor rush of current has designed soft start in DC side when powering on for anti-locking apparatus in three-phase circuit, and when voltage was elevated to certain value, soft start switch closed, soft start resistance short circuit.For the filtering high order harmonic component relevant effectively with switching frequency, in the AC side of three-phase bridge each go up mutually all gone here and there earlier an inductance again and a high pass filter, and then insert electrical network, compensating load electric current.Energy feedback of the present invention simultaneously and harmonic reactive-load compensation system are total to ground wire with uncontrollable diode rectification device and are connected, and energy feedback promptly of the present invention and harmonic reactive-load compensation system are the original systems that inserts in parallel.
Relation between three parts of control system 8 is as follows, and the current sensor 8.1 never input path of controllable diode rectifying device 4 and the path that filter 10 flows to electrical network obtains load current i respectively
La, i
LbWith offset current i
Ca, i
CbVoltage sensor 8.2 obtains the electromotive force voltage of electrical network 3 and the voltage Vdc2 at power three-phase bridge DC side electric capacity of voltage regulation C2 two ends respectively from the dc bus capacitor C2 two ends of electrical network 3 and power three-phase bridge 9, again the electric current and the voltage signal that obtain is sent into controlling and driving plate 8.3.Obtain the switching signal S1～S6 of power switch pipe in the power three-phase bridge by the control action of controlling and driving plate, drive the power switch pipe work in the three-phase bridge.The controlling and driving plate can adopt DSP to realize, also has and isolates and defencive function.
Claims (2)
1, a kind of energy feedback and harmonic reactive-load compensation system that is applicable to rectifying device is characterized in that: this system comprises power switch pipe (7), control device (8), power three-phase bridge (9) and filter (10);
The positive pole of power switch pipe (7) connects the DC bus-bar voltage output of uncontrollable diode rectification device, and its negative pole connects the DC bus-bar voltage positive pole of power three-phase bridge (9); The DC bus-bar voltage cathode output end of power three-phase bridge (9) links to each other with the DC bus-bar voltage cathode output end of uncontrollable diode rectification device (4);
Control device (8) is used to obtain the input load electric current of uncontrollable diode rectification device (4), the offset current of filter (10) output and the DC bus-bar voltage of power three-phase bridge (9), according to the parameter generating switching signal of obtaining, the power switch pipe of power controlling three-phase bridge (9) opening and turn-offing respectively;
Power three-phase bridge (9) is used for providing DC bus-bar voltage to control device (8), and the closure of the commands for controlling power switch pipe that provides according to control device (8) produces offset current, and offers filter (10);
Filter (10) is accepted the offset current from power three-phase bridge (9), leaches high order harmonic component, offset current is compensated into electrical network (3), and this current signal is offered control device (8).
2, system according to claim 1, it is characterized in that: power switch pipe (7) is diode D7, power three-phase bridge (9) adopts the three-phase half-bridge structure, and the electric capacity of voltage regulation negative pole of power three-phase bridge (9) DC side links to each other with the DC side electric capacity of voltage regulation negative pole of uncontrollable diode rectification device (4); Bank of filters (10) takes inductance to form Filter Structures, control device (8) is by current sensor (8.1), voltage sensor (8.2) and controlling and driving plate (8.3) are formed, never the input path of controllable diode rectifying device (4) and the path that filter (10) flows to electrical network obtain current signal to current sensor (8.1) respectively, voltage sensor (8.2) obtains voltage signal from dc bus capacitor (C2) two ends of electrical network and power three-phase bridge (9), controlling and driving plate (8.3) receives above-mentioned current signal and voltage signal, produce the switching signal of power switch pipe in the power three-phase bridge, drive the power switch pipe work in the three-phase bridge.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CNA2007101686653A CN101237185A (en) | 2007-12-07 | 2007-12-07 | Energy feedback and harmonic wave passive compensation system applicable to commutation device |
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| Application Number | Priority Date | Filing Date | Title |
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| CNA2007101686653A CN101237185A (en) | 2007-12-07 | 2007-12-07 | Energy feedback and harmonic wave passive compensation system applicable to commutation device |
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Cited By (13)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101917020A (en) * | 2010-08-04 | 2010-12-15 | 长沙理工大学 | Lift energy feedback, reactive compensation and switched-off emergency running method and system |
| CN102088280A (en) * | 2009-12-07 | 2011-06-08 | 株式会社电装 | Device for driving switching elements |
| CN101527458B (en) * | 2009-04-08 | 2011-11-23 | 日立电梯（中国）有限公司 | Parallel type energy feedback elevator system |
| CN102403957A (en) * | 2011-11-08 | 2012-04-04 | 厦门大学 | Harmonic-free frequency conversion speed adjusting device |
| CN104882889A (en) * | 2015-06-05 | 2015-09-02 | 江苏同芯电气科技有限公司 | Composite circuit integrating rectification, active power filtering and energy feedback braking functions |
| CN105429179A (en) * | 2015-12-22 | 2016-03-23 | 山东华天电气有限公司 | Special filtering energy feedback apparatus and control method for pumping unit |
| CN105599640A (en) * | 2016-03-07 | 2016-05-25 | 西华大学 | Apparatus and method for suppressing overhead contact system overvoltage caused by regenerative braking |
| CN107112914A (en) * | 2014-10-15 | 2017-08-29 | 大金工业株式会社 | Active filter and AC DC conversion equipment |
| CN108242816A (en) * | 2016-12-27 | 2018-07-03 | 南京理工大学 | A kind of Three-Phase Parallel multi-functional converter and its method of work |
| CN109462355A (en) * | 2018-11-19 | 2019-03-12 | 南京航空航天大学 | A kind of novel and multifunctional motor driven auxiliary device |
| CN111277154A (en) * | 2020-01-19 | 2020-06-12 | 中国人民解放军海军工程大学 | Integrated non-similar redundant rectifying device |
| CN113346495A (en) * | 2021-07-14 | 2021-09-03 | 山东博诚电气有限公司 | Motor control system and method |
| CN113381410A (en) * | 2021-07-14 | 2021-09-10 | 山东博诚电气有限公司 | Frequency converter and filtering method thereof |
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2007
- 2007-12-07 CN CNA2007101686653A patent/CN101237185A/en active Pending
Cited By (18)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101527458B (en) * | 2009-04-08 | 2011-11-23 | 日立电梯（中国）有限公司 | Parallel type energy feedback elevator system |
| CN102088280A (en) * | 2009-12-07 | 2011-06-08 | 株式会社电装 | Device for driving switching elements |
| CN102088280B (en) * | 2009-12-07 | 2013-11-06 | 株式会社电装 | Device for driving switching elements |
| CN101917020B (en) * | 2010-08-04 | 2012-10-03 | 长沙理工大学 | Lift energy feedback, reactive compensation and switched-off emergency running method and system |
| CN101917020A (en) * | 2010-08-04 | 2010-12-15 | 长沙理工大学 | Lift energy feedback, reactive compensation and switched-off emergency running method and system |
| CN102403957A (en) * | 2011-11-08 | 2012-04-04 | 厦门大学 | Harmonic-free frequency conversion speed adjusting device |
| CN107112914A (en) * | 2014-10-15 | 2017-08-29 | 大金工业株式会社 | Active filter and AC DC conversion equipment |
| CN107112914B (en) * | 2014-10-15 | 2019-07-02 | 大金工业株式会社 | Active filter and AC DC conversion equipment |
| CN104882889A (en) * | 2015-06-05 | 2015-09-02 | 江苏同芯电气科技有限公司 | Composite circuit integrating rectification, active power filtering and energy feedback braking functions |
| CN105429179B (en) * | 2015-12-22 | 2018-07-20 | 山东华天电气有限公司 | The special filtering of pumping unit can present device and control method |
| CN105429179A (en) * | 2015-12-22 | 2016-03-23 | 山东华天电气有限公司 | Special filtering energy feedback apparatus and control method for pumping unit |
| CN105599640A (en) * | 2016-03-07 | 2016-05-25 | 西华大学 | Apparatus and method for suppressing overhead contact system overvoltage caused by regenerative braking |
| CN108242816A (en) * | 2016-12-27 | 2018-07-03 | 南京理工大学 | A kind of Three-Phase Parallel multi-functional converter and its method of work |
| CN109462355A (en) * | 2018-11-19 | 2019-03-12 | 南京航空航天大学 | A kind of novel and multifunctional motor driven auxiliary device |
| CN111277154A (en) * | 2020-01-19 | 2020-06-12 | 中国人民解放军海军工程大学 | Integrated non-similar redundant rectifying device |
| CN113346495A (en) * | 2021-07-14 | 2021-09-03 | 山东博诚电气有限公司 | Motor control system and method |
| CN113381410A (en) * | 2021-07-14 | 2021-09-10 | 山东博诚电气有限公司 | Frequency converter and filtering method thereof |
| NL2032361A (en) * | 2021-07-14 | 2023-01-19 | Shandong Bocheng Electric Co Ltd | Motor control system and method |
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