CN203119838U - High-performance four-quadrant frequency converter - Google Patents
High-performance four-quadrant frequency converter Download PDFInfo
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- CN203119838U CN203119838U CN2013200514010U CN201320051401U CN203119838U CN 203119838 U CN203119838 U CN 203119838U CN 2013200514010 U CN2013200514010 U CN 2013200514010U CN 201320051401 U CN201320051401 U CN 201320051401U CN 203119838 U CN203119838 U CN 203119838U
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Abstract
The utility model discloses a high-performance four-quadrant frequency converter, so as to realize controllable direct current voltage output, small grid-side current harmonic content, and bidirectional flow of energy, and the frequency converter obeys an intermittent operation rule, and is relatively energy-saving. No matter in a circumstance of heavy load, light load, or even energy feedback, the direct current side voltage can be kept at a set value through control. The control process is that a rectifier and an inverter are combined to perform unified coordination control, the rectifier uses information of the inverter side to perform feedforward control so as to obtain relatively good direct current bus voltage control performance and fast dynamic response speed, and an operation rule of the rectifier is matched with a motor operation rule of the inverter side to achieve the purpose of intermittent operation, so that bidirectional flow of energy can be realized, thereby saving electric power. The high-performance four-quadrant frequency converter has the characteristics of being low in grid-side current harmonic content and high in sine degree, having no harmonic pollution to a power grid, being capable of performing unit power factor operation of the rectifier, having an automatic boost function, and having the capability of controlling the direct current bus voltage to be stable.
Description
Technical field
The utility model relates to field of power electronics, relates in particular to a kind of high-performance four-quadrant frequency converter that drives permanent magnetic linear synchronous motor.
Background technology
Traditional motor-driven uses diode rectifier bridge that alternating current is transformed into direct current with the frequency converter front end more, and the subject matter that this frequency changer exists is:
1) input current contains bigger harmonic wave.Because the characteristics of diode rectifier bridge, input current can't directly be controlled, the total percent harmonic distortion of electric current THD() generally more than 40%, cause incoming line loss increase and electromagnetic interference problem, be the major reason that causes present electric network pollution, this pollution problem will become more and more serious along with the continuous increase that current transformer in the grid equipment is used.
2) lower from electrical network absorbing reactive power, input power factor, and uncontrollable.
3) can't realize the two-way flow of energy.Because diode rectifier bridge only allows the electric current one-way flow, energy can only be transmitted to output by input, can't reverse flow.
4) output dc voltage is uncontrollable.DC bus-bar voltage can be fallen to some extent during heavy duty, and can the lifting direct voltage during energy feedback, there is the danger of direct current overvoltage, thereby jeopardizes device for power switching, therefore powerful direct current overvoltage absorption resistance and switching device need be installed additional, the waste of energy can be caused so again.
In addition, at present in the world many major companies released energy feedback four-quadrant frequency converter one after another.ACS800 as ABB company, ACS1000, ACS2000, serial four-quadrant frequency converter such as ACS5000, the GM150 of Siemens Company, SM150, products such as GL150, but its performance parameter and domestic industry standard have certain difference, and are not suitable for being applied to drive special permanent magnetic linear synchronous motor load.
As: Chinese patent ZL02104139.3, a kind of no-harmonic wave pollution high voltage frequency converter energy back feed device is provided, it comprises a plurality of feed back bridgings and feed back bridging control circuit.But it only is an energy back feed device, can't improve the harmonic pollution problem of diode rectification, also can't realize the control to dc voltage, input power factor simultaneously.
For another example: Chinese patent ZL200810120160.4 has proposed a kind of DC lateral voltage controllable 4 quadrant frequency transformer and method thereof.Its realizes direct voltage control, improve the current on line side quality and with regenerative electric energy feedback to electrical network, but it only lays particular emphasis on the control of front-end rectifier, especially stresses the control method of direct voltage.But, do not relate to the technical scheme of whole frequency conversion system being carried out master-plan.
Also as: Chinese patent ZL200910107449.7 has proposed a kind of three-phase synchronous rectification circuit and a kind of control method of circuit of synchronous rectification is provided.But it is only at synchronous rectifier itself, there is no to relate to the motor-driven related content.
Summary of the invention
In view of above-mentioned present situation, the purpose of this utility model aims to provide a kind of high performance four-quadrant frequency converter, overcome conventional motors drive, energy big with the frequency converter input harmonics can not two-way flow, power factor is non-adjustable, direct voltage is not controlled, rectification side and the inharmonic problem of inversion side.
The method that another purpose of the present utility model also provides rectifier and inverter to coordinate to control makes The whole control system realize intermittent moving law according to operating characteristics of motor.
Technical solution of the present utility model realizes by following measure.A kind of high-performance four-quadrant frequency converter comprises:
The main contactor of Lian Jieing, pre-charge resistance, three-phase reactor, rectifier, inverter successively, this inverter is connected with permanent magnetic linear synchronous motor, two ends at described pre-charge resistance are parallel with auxiliary contactor, and be provided with electrochemical capacitor between rectifier and the inverter, be connected with three-phase alternating-current supply by main contactor;
Have that network voltage detection, input current detect, DC bus-bar voltage detects, the output of direct current detection all links to each other with sampling module in the control system, the rectifier and trigger pulse of control system all is connected with the control end of corresponding full-controlled switch device respectively by optical fiber or twisted-pair feeder with the inversion trigger impulse.
The rectifier that this is novel and inverter are formed the unified control system of coordinating, The whole control system has intermittent moving law according to the operation characteristic of permanent magnetic linear synchronous motor load, rectifier utilizes the power feedforward of inverter side to improve the control performance of DC bus-bar voltage, rectifier utilizes the moving law of inverter side motor simultaneously, the not intermittence operation of consumed power during realization rectifier and inverter are out of service.
During this is novel, identical on topological structure for rectifier and the inverter of the power circuit that drives permanent magnetic linear synchronous motor, the topological structure of formation " back-to-back "; But all adopt full-control type switch-off power device in rectifier and the inverter, power device is insulated gate transistor IGBT, each insulated gate transistor IGBT carries fly-wheel diode, in controlled rectifier, be power supply A phase input between first power device S1 and second the power device S4, be power supply B phase input between the 3rd power device S3 and the 4th the power device S6, be power supply C phase input between the 5th power device S5 and the 6th the power device S2, in inverter, be inverter U phase output terminal between first power device G1 and second the power device G4, being inverter V phase output terminal between the 3rd power device G3 and the 4th the power device G6, is inverter W phase output terminal between the 5th power device G5 and the 6th the power device G2.
During this is novel, the voltage and current detecting device that is used for the driving permanent magnetic linear synchronous motor comprises: network voltage detection is placed on secondary side or the primary side of main contactor, input current detects and is connected in the incoming line of reactor, DC bus-bar voltage detects and is connected in parallel on the electrochemical capacitor two ends, and direct current detection is connected in the anodal outlet line of controlled rectifier.
The control method that this is novel, rectifier and inverter are formed the unified control system of coordinating, has intermittent moving law according to operating characteristics of motor, the DC bus-bar voltage controlling unit that comprises rectifier in this control system, active current and reactive current controlling unit, power feedforward link, rectifier and inverter jointly control link, given intermittent duty rule link; Wherein the DC bus-bar voltage controlling unit is the poor pi regulator G1 (s) that sends busbar voltage set-point and value of feedback into, adjuster output active current set-point, add that the calculated value of power feedforward link obtains the final active current set-point of rectifier, real component and idle component with the actual input current of rectifier compares with active current set-point and reactive current set-point respectively then, its difference is sent into the reference voltage set-point that pi regulator G2 (s) obtains rectifier respectively, the feedforward of recycling voltage on line side obtains final modulating wave voltage given value, at last it is sent into pwm pulse generator control rectifier by the instruction reliability service.
This novel particular job characteristic according to the permanent magnetic linear synchronous motor load, preset in advance is reserved different intermittent duty rules and the given running frequency of motor, inverter control algorithm generates control command according to these set points, pwm pulse generator produces the trigger impulse of needs according to control command then, drive the device for power switching action of inverter side, the cycle reciprocating action of control permanent magnetic linear synchronous motor.
[0018]During this is novel, the cooperation control of rectifier and inverter comprises, rectifier utilizes the power feedforward of inversion side to improve the control performance of DC bus-bar voltage, the pwm pulse generation link of rectifier is controlled by the intermittent duty rule of inverter, simultaneously the active current set-point of rectifier wherein a part be that power by inverter feedovers and obtains.
The good effect that this novel four-quadrant frequency converter has is:
1) can realize the current on line side sineization, total percent harmonic distortion (THD) can be controlled below 5%, to the electrical network no-harmonic wave pollution.
2) energy can two-way flow, no longer needs the resistance that consumes energy, and reduces the wastage, energy savings.
3) unity power factor that can realize rectifier moves.
4) output dc voltage is controlled.No matter when heavy duty, underloading even energy feedback, dc voltage can both hold it in a set point by control.
5) rectifier and inverter have the ability of co-ordination, and whole system possesses the characteristic of intermittent work according to the special operation characteristic of motor.
Description of drawings
Fig. 1 is this novel power circuit schematic diagram;
Fig. 2 is the control principle figure of system of Fig. 1;
Fig. 3 is the moving law figure of Fig. 2.
Embodiment
Below in conjunction with accompanying drawing embodiment to this novel elaborating.
As shown in Figure 1, a kind of high-performance four-quadrant frequency converter, the three-phase alternating-current supply 1 that comprises power circuit, and the main contactor 2 that is connected with three-phase alternating-current supply 1, be connected with pre-charge resistance 3 inputs by main contactor 2, auxiliary contactor 4 is connected in parallel on pre-charge resistance 3 two ends, pre-charge resistance 3 outputs are connected with three-phase reactor 5 inputs, three-phase reactor 5 outputs are connected with rectifier 6, the output of controlled rectifier 6 electrochemical capacitor 7 in parallel provides the DC power supply that needs to converter plant.The output of electrochemical capacitor 7 is connected with the input of inverter 8, the power circuit that inverter 8 outputs and permanent magnetic linear synchronous motor 9 are connected to form.In the present embodiment, also comprise network voltage detection 10, input current detection 11, DC bus-bar voltage detection 12, direct current detection 13, the output of described network voltage detection 10, input current detection 11, DC bus-bar voltage detection 12, direct current detection 13 all links to each other with the sampling module 15 of control system 14.Rectifier and trigger pulse 16 and the inversion trigger impulse 17 of control system 14 all are connected on the control end of full-control type device by optical fiber or twisted-pair feeder.
In the present embodiment, identical on topological structure for rectifier 6 and the inverter 8 of the power circuit that drives permanent magnetic linear synchronous motor, the topological structure of formation " back-to-back "; But all adopt full-control type switch-off power device in rectifier 6 and the inverter 8, power device is insulated gate transistor IGBT, each insulated gate transistor IGBT carries fly-wheel diode, in rectifier, be power supply A phase input between first power device S1 and second the power device S4, be power supply B phase input between the 3rd power device S3 and the 4th the power device S6, be power supply C phase input between the 5th power device S5 and the 6th the power device S2, in inverter, be inverter U phase output terminal between first power device G1 and second the power device G4, being inverter V phase output terminal between the 3rd power device G3 and the 4th the power device G6, is inverter W phase output terminal between the 5th power device G5 and the 6th the power device G2.
In the present embodiment, the voltage and current detecting device that is used for the driving permanent magnetic linear synchronous motor comprises: network voltage detection 10 is placed on secondary side or the primary side of main contactor 2, input current detects 11 and is connected in the incoming line of reactor 5, DC bus-bar voltage detects 12 and is connected in parallel on electrochemical capacitor 7 two ends, and direct current detection 13 is connected in the anodal outlet line of controlled rectifier 3.
Provided the control principle figure of system as Fig. 2, the control system 14 of present embodiment is rectifier 6 and inverter 8 to be united coordinate control, and The whole control system has intermittent moving law according to the operation characteristic of permanent magnetic linear synchronous motor.
Described control system comprises the DC bus-bar voltage controlling unit 18 of rectifier 6, active current and reactive current controlling unit 19, power feedfoward control link 20, and the cooperation controlling unit 21 of rectifier 6 and inverter 8.
In the present embodiment, DC bus-bar voltage controlling unit 18 is the poor pi regulator G1 (s) that sends busbar voltage set-point Udcr and value of feedback Udc into, adjuster output active current set-point ird, add that power feedforward link set-point ifd obtains the final active current set-point (ird+ifd) of rectifier 6, real component isd and idle component isq with controlled rectifier 6 actual input currents compares with active current set-point (ird+ifd) and reactive current set-point irq respectively then, its difference is sent into reference voltage set-point Urd and the Urq that pi regulator G2 (s) obtains rectifier 6, recycling voltage on line side feedforward value Usd and Usq obtain final modulating wave voltage given value Urefd and Urefq, at last it is sent into pwm pulse generator and obtain rectifier trigger pulse 16, control rectifier 6 reaches the purpose of stablizing DC bus-bar voltage and guaranteeing the input current unity power factor by the instruction reliability service.Rectifier 6 utilizes power feedforward link to improve the controllability of DC bus-bar voltage, utilizes the start and stop of the given moving law control rectifier 6 of inverter 8 to reach the intermittent duty purpose constantly.
The control command of the inverter 8 of present embodiment mainly comprises, given moving law and the running frequency of permanent magnetic linear synchronous motor.Just can produce the inverter trigger impulse 17 of needs according to the pwm pulse generator of moving law and running frequency inverter, the control permanent magnetic linear synchronous motor is pressed instruction operation.Simultaneously the intermittent duty rule of inverter is passed to rectifier 6 and reach system coordination operation purpose.
The rectifier that this is novel and the cooperation control method of inverter, rectifier utilizes the power feedforward of inversion side to improve the control performance of DC bus-bar voltage, the pwm pulse generation link of rectifier is controlled by the intermittent duty rule of inverter, simultaneously the active current set-point of rectifier wherein a part be that power by inverter feedovers and obtains.
The control method of the inverter that this is novel, particular job characteristic according to the permanent magnetic linear synchronous motor load, preset different intermittent duty rules and the running frequency of reserving permanent magnetic linear synchronous motor in advance, the pwm pulse generator of inverter side utilizes the trigger impulse 17 that these set points produce to be needed then, drive the device for power switching action of inverter side, thus the intermittent duty of control linear electric motors.
The inverter of moving law link 22 and the moving law figure of rectifier have been provided as Fig. 3.Determine running time (t3-t2) and the dwell time (t6-t3) of inverter according to given intermittent duty rule, rectifier utilizes this temporal information, and it will just start constantly at t1, prior to the startup of inverter t2 constantly; Rectifier will be constantly out of service at t4 simultaneously, lag behind the moment t3 out of service of inverter, thereby guarantee before the invertor operation and the whole service process in rectifier set up DC bus-bar voltage, also reached the purpose that possesses intermittent duty according to the electric machine operating characteristic whole system.Wherein t1-t2-t3-t4-t5 is a cycle of operation, and t5-t6-t7-t8-t9-t10 is the next cycle of operation, and operation characteristic is identical.During rectifier and inverter were out of service, whole frequency-converter device is consumed power not, and therefore with respect to the traditional frequency conversion device, this new type inverter has more energy-conservation characteristics.
Claims (5)
1. a high-performance four-quadrant frequency converter is characterized in that, comprising:
The main contactor of Lian Jieing (2), pre-charge resistance (3), three-phase reactor (5), controlled rectifier (6), inverter (8) successively, this inverter (8) is connected with permanent magnetic linear synchronous motor (9), be parallel with auxiliary contactor (4) at the two ends of described pre-charge resistance, and be provided with electrochemical capacitor (7) between controlled rectifier (6) and the inverter (8), connect to form power circuit by main contactor (2) and three-phase alternating-current supply (1);
Have network voltage detection (10), input current and detect output that (11), DC bus-bar voltage detect (12), direct current detection (13) and all link to each other with sampling module (15) in the control system (14), the rectifier and trigger pulse (16) of control system (14) all is connected with the control end of corresponding full-control type power device respectively by optical fiber or twisted-pair feeder with inversion trigger impulse (17).
2. a kind of high-performance four-quadrant frequency converter according to claim 1, it is characterized in that, controlled rectifier (6) and inverter (8) for the power circuit that drives permanent magnetic linear synchronous motor are identical on topological structure, form the topological structure of " back-to-back "; Controlled rectifier (6) and inverter (8) but in all adopt full-control type switch-off power device, power device is insulated gate transistor IGBT, each insulated gate transistor IGBT carries fly-wheel diode, in controlled rectifier, be power supply A phase input between first power device S1 and second the power device S4, be power supply B phase input between the 3rd power device S3 and the 4th the power device S6, be power supply C phase input between the 5th power device S5 and the 6th the power device S2, in inverter, be inverter U phase output terminal between first power device G1 and second the power device G4, being inverter V phase output terminal between the 3rd power device G3 and the 4th the power device G6, is inverter W phase output terminal between the 5th power device G5 and the 6th the power device G2.
3. a kind of high-performance four-quadrant frequency converter according to claim 1, it is characterized in that, the voltage and current detecting device that is used for the driving permanent magnetic linear synchronous motor comprises: network voltage detection (10) is placed on secondary side or the primary side of main contactor (2), input current detects (11) and is connected in the incoming line of reactor (5), DC bus-bar voltage detects (12) and is connected in parallel on electrochemical capacitor (7) two ends, and direct current detection (13) is connected in the anodal outlet line of controlled rectifier (3).
4. a kind of high-performance four-quadrant frequency converter according to claim 1, it is characterized in that, rectifier and inverter are formed the unified control system of coordinating, has intermittent moving law according to operating characteristics of motor, the DC bus-bar voltage controlling unit (18) that comprises rectifier in this control system, active current and reactive current controlling unit (19), power feedforward link (20), rectifier and inverter jointly control link (21), given intermittent duty rule link (22); Wherein the DC bus-bar voltage controlling unit is the poor pi regulator G1 (s) that sends busbar voltage set-point and value of feedback into, adjuster output active current set-point, add that the calculated value of power feedforward link obtains the final active current set-point of rectifier, real component and idle component with the actual input current of rectifier compares with active current set-point and reactive current set-point respectively then, its difference is sent into the reference voltage set-point that pi regulator G2 (s) obtains rectifier respectively, the feedforward of recycling voltage on line side obtains final modulating wave voltage given value, at last it is sent into pwm pulse generator control rectifier by the instruction reliability service.
5. a kind of high-performance four-quadrant frequency converter according to claim 4, it is characterized in that, the cooperation control of rectifier and inverter comprises, rectifier utilizes the power feedforward of inversion side to improve the control performance of DC bus-bar voltage, the pwm pulse generation link of rectifier is controlled by the intermittent duty rule of inverter, simultaneously the active current set-point of rectifier wherein a part be that power by inverter feedovers and obtains.
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| CN2013200514010U CN203119838U (en) | 2013-01-30 | 2013-01-30 | High-performance four-quadrant frequency converter |
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Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104601006A (en) * | 2015-03-02 | 2015-05-06 | 湖南中科电气股份有限公司 | Special power source for composite electromagnetism constraint vibration device and control method of special power source |
| CN105790557A (en) * | 2016-04-21 | 2016-07-20 | 四川航电微能源有限公司 | Circuit for reducing input harmonics of AC power supply |
| CN106208735A (en) * | 2016-08-24 | 2016-12-07 | 中南大学 | The matrix converter of a kind of third-harmonic zero-sequence voltage and control method |
-
2013
- 2013-01-30 CN CN2013200514010U patent/CN203119838U/en not_active Expired - Lifetime
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104601006A (en) * | 2015-03-02 | 2015-05-06 | 湖南中科电气股份有限公司 | Special power source for composite electromagnetism constraint vibration device and control method of special power source |
| CN105790557A (en) * | 2016-04-21 | 2016-07-20 | 四川航电微能源有限公司 | Circuit for reducing input harmonics of AC power supply |
| CN106208735A (en) * | 2016-08-24 | 2016-12-07 | 中南大学 | The matrix converter of a kind of third-harmonic zero-sequence voltage and control method |
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Owner name: HEBEI GUOCHUANG PETROLEUM MACHINERY CO., LTD. Free format text: FORMER NAME: QINHUANGDAO GUONENG PETROLEUM EQUIPMENT CO., LTD. |
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Address after: 066004, West Lake Road, Qinhuangdao economic and Technological Development Zone, Hebei, China Patentee after: HEBEI GUOCHUANG PETROLEUM EQUIPMENT CO.,LTD. Address before: 066004, West Lake Road, Qinhuangdao economic and Technological Development Zone, Hebei, China Patentee before: QINHUANGDAO GUONENG PETROLEUM EQUIPMENT CO.,LTD. |
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Granted publication date: 20130807 |