CN202281807U - Rated capacity test device of active front end voltage type AC-DC-AC frequency converter - Google Patents
Rated capacity test device of active front end voltage type AC-DC-AC frequency converter Download PDFInfo
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- CN202281807U CN202281807U CN2011204296891U CN201120429689U CN202281807U CN 202281807 U CN202281807 U CN 202281807U CN 2011204296891 U CN2011204296891 U CN 2011204296891U CN 201120429689 U CN201120429689 U CN 201120429689U CN 202281807 U CN202281807 U CN 202281807U
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Abstract
The present utility model relates to a rated capacity test device of an active front end voltage type AC-DC-AC frequency converter. The device is characterized in that the device comprise a frequency converter, a transformer device and an electric power network, an active front end rectifier AFER and an inverter INV of the frequency converter are respectively connected with the electric power network through the transformer device, power and output power factors of the frequency converter can be flexibly adjusted through adjusting relevant settings of the AFER and the INV, reversible operation tests of rated capacity under different power factors can be realized, and tests of rated capacity of a whole set of frequency converters and temperature rise of power devices can be carried out. The device is reasonable in design, through adjusting output settings of the active front end rectifier and the inverter, and output power and power factors of the frequency converter, reversible operation tests of rated capacity can be carried out under different power factors, and accurate tests of the whole set of frequency converters and temperature rise of power devices can be carried out.
Description
Technical field
The utility model belongs to the frequency converter field, especially a kind of rated capacity test unit of active front end voltage-type ac-dc-ac frequency converter.
Background technology
Variable-frequency control technique has become a kind of important means that industrial circle was saved energy and reduce the cost, improved technological process, improves the quality of products and improve environment, promotes technical progress; Along with the development of novel high-power power electronic devices, all kinds of big-power transducers have been widely used in the large scale industry production equipment.The high-performance big-power transducer adopts active front end AC-DC-AC topology to be the main flow structure at present.
The rated capacity test is one of most important content of the test of frequency converter; For the middle low power frequency converter; Traditional rated capacity test method mainly contains two kinds: a kind of frequency converter that tried is exported the load of band passive impedance, and another kind is tried the active load of frequency converter output band frequency converter-motor unit.
During by the active load of examination frequency converter output band frequency converter-motor unit; With two power and the suitable motor of quilt examination frequency converter; Coaxial or be connected to form unit through gear case, accompany wherein motor of examination current transformer control with a cover, tried another motor of Frequency Converter Control.Accompany the examination current transformer and tried frequency converter through control in the test; Make a motor run on electronic, another runs on generating state; Thereby make and form required specified test torque between two motors in the unit; Constitute the flow of power of formula back-to-back, the loss of unit and the loss of accompanying the examination current transformer are than being reduced greatly by the passive impedance loss in the load of examination frequency converter output band passive impedance.Accompany the examination current transformer generally with the work of torque closed loop during test; Tried frequency converter with speed closed loop or frequency closed loop or operate in open loop state; Accompany examination current transformer controlling torque direction, tried the Frequency Converter Control velocity reversal, through the combination realization four-quadrant reversible operation test of speed polarity and torque polarity.The advantage of this test method is to carry out reversible test, can carry out stable state, dynamic property test, and the process of the test power attenuation is less etc.; Shortcoming is unit equipment and accompanies the examination converter system complicated, and equipment investment is big, and testing laboratory takes up an area of big, and plant equipment is difficult in maintenance, is not suitable for the rated capacity test that high-power or super high power is tried frequency converter.
For high-power or super high power frequency converter; Restriction because of be put to the test place capacity (like frequency converter-motor unit), place, power supply capacity etc.; Be difficult to carry out stable rated capacity test, specified temperature rise and loss test and test can only be undertaken by the unit usually, then the whole rated capacity of frequency converter are estimated; Perhaps carry out actual test, but on-the-spot test generally is difficult to the nominal operating conditions of continous-stable at frequency converter operation scene.The proving installation of having reported to power device or power cell, seldom has the test method to big-power transducer complete machine rated capacity mostly.Therefore, the effective energy-conservation rated capacity method of testing of research ac-dc-ac frequency converter and test unit are very necessary.
Summary of the invention
The purpose of the utility model is to overcome the deficiency of prior art; A kind of rated capacity test unit to active front end voltage-type ac-dc-ac frequency converter is proposed; Comprise the Tests at Steady State of rated capacity under reversible operation, the different loads power factor etc., a whole set of frequency converter nominal output, power device temperature rise are accurately tested.
The utility model solves its technical matters and takes following technical scheme to realize:
A kind of rated capacity test unit of active front end voltage-type ac-dc-ac frequency converter; Comprise frequency converter, device for transformer and electric power network; The active front-end rectifier AFER of frequency converter and inverter INV insert electric power network through device for transformer respectively; Through regulating the size of relevant given flexible transducer power of AFER and output power factor with INV; Carry out the reversible operation test of rated capacity under the different capacity factor, a whole set of frequency converter rated capacity and power device temperature rise are tested.
And described active front end voltage-type ac-dc-ac frequency converter mainly is made up of active front-end rectifier AFER, inverter INV and dc filter capacitor.
And described device for transformer is transformer T1 and transformer T2, and the active front-end rectifier AFER of frequency converter and inverter INV insert electric power network through transformer T1 and transformer T2 respectively; Perhaps described device for transformer is one two cracking transformer T, and the active front-end rectifier AFER of frequency converter and inverter INV insert electric power network through two cracking transformer T respectively; Perhaps described device for transformer is transformer T1 and reactor TD, and the active front-end rectifier AFER of frequency converter and inverter INV insert electric power network through transformer T1 and reactor TD respectively.
And described active front-end rectifier AFER and inverter INV all adopt active power and the control of reactive power independent vector.
And the described relevant given reactive current active current given, inverter INV that comprises AFER is given and reactive current is given.
And described active front-end rectifier AFER is two circuit structures that topology is identical with inverter INV, and DC side links to each other back-to-back through filter capacitor and constitutes active front end voltage-type ac-dc-ac frequency converter.
The advantage and the good effect of the utility model are:
1, this test unit circuit is simple, and equipment is few.Except that by the examination frequency converter, only need two transformers (or two cracking transformer or a transformer and a reactor) and contactor etc.With respect to the active load test unit of frequency converter-motor unit, need not to solve the problem of frequency converter-motor unit installation, support equipment and maintenance of machine.
2, this test unit is with respect to the active load test unit of frequency converter-motor unit, and the test method of the utility model does not have the loss of electric machine and unit mechanical loss, unit cooling loss etc., and the power that is consumed is little, and efficient is high.
3, this test unit can carry out required different capacity of frequency converter and the test of different capacity factor, and the operating condition under the various power factor conditions of simulation test is realized the reversible operation test.
4, this test unit can test frequency converter's each power device under the different capacity factor temperature rise and loss, thus the specified fan-out capability of frequency converter under the different capacity factor accurately assessed.
Description of drawings
Circuit diagram when Fig. 1 is two transformers of the utility model employing;
Fig. 2 is the circuit diagram of the utility model when adopting two cracking transformers;
Circuit diagram when Fig. 3 is the utility model transformer of employing and a reactor;
Fig. 4 is the test principle block diagram of the utility model;
Fig. 5 is a phase voltage first-harmonic u and this phase current first-harmonic i synoptic diagram of inverter INV output;
Fig. 6 is the current flowing path synoptic diagram on brachium pontis of inverter INV;
Embodiment
Below in conjunction with accompanying drawing the utility model embodiment is done further detailed description:
A kind of test unit of active front end voltage-type ac-dc-ac frequency converter; As shown in Figure 1; Comprise frequency converter, transformer T1, transformer T2 and electric power network; The active front-end rectifier AFER of frequency converter and inverter INV insert electric power network through transformer T1, transformer T2 respectively, and this active front end voltage-type ac-dc-ac frequency converter mainly is made up of active front-end rectifier AFER, inverter INV and dc filter capacitor.This experimental provision makes the energy of electric power network can be fed back to electric power network from frequency converter through inverter INV again from active front-end rectifier AFER input converter, forms the loop of power circuit; Simultaneously; The leakage reactance of transformer also can be used as the load reactance of AFER; Through regulating the size of relevant given flexible transducer power of AFER and output power factor with INV; Carry out the reversible operation test of rated capacity under the different capacity factor, a whole set of frequency converter rated capacity and power device temperature rise are tested.Transformer T1 in this test unit, transformer T2 can use one two cracking transformer to substitute, and the active front-end rectifier AFER of frequency converter and inverter INV insert electric power network through two cracking transformer T respectively, and be as shown in Figure 2.Transformer T2 also can use a reactor TD in this test unit, and the active front-end rectifier AFER of frequency converter and inverter INV insert electric power network through transformer T1 and reactor TD respectively, and be as shown in Figure 3.With structure shown in Figure 1 is example, and AFER is connected with electric power network through transformer T1, T2 respectively with INV.During test, power forms the closed-loop path through T1 → AFER → INV → T2 → T1, is the narration of convenient back, stipulates here by the power of net side inflow AFER or INV to just, otherwise is to bear from the power that AFER or INV flow into electric power network.Since directed with the electric power network voltage vector, be exactly the polarity of active current and reactive current so the power circuit polarity of regulation is actual here.
The Control Software of inverter is made amendment by control block diagram shown in Figure 4, perhaps inverter is adopted the controller identical with rectifier.This is because the control system of the inverter in most frequency converters designs to motor variable-frequency speed-regulating; When adopting the test unit of the utility model; Require control system all to adopt active power and the control of reactive power independent vector, therefore will make suitable modification the control system of inverter.
Relevant with INV given through regulating AFER, but the size of flexible transducer power and output power factor is carried out the reversible operation test of rated capacity under the different capacity factor, and a whole set of frequency converter rated capacity and power device temperature rise are tested.
As shown in Figure 4, said AFER principle of work is following: power taking power electrical network three-phase voltage signal detects the phase theta and the amplitude U of electric power network voltage vector to phase-locked loop pll
dSet the DC voltage ratings
With DC voltage actual value U
DcRelatively the back is carried out closed loop adjustment control through voltage regulator AUR to DC voltage, and its output is given as active current
Reactive current is given
Draw according to test predetermined electric power Factor Calculation; Detect AFER three-phase alternating current signal, calculate active current actual value i through 3/2 conversion and vector revolution VD1
IPAnd reactive current actual value i
IQActive current is given
With active current actual value i
IP, reactive current is given
With reactive current actual value i
IQRespectively relatively after, carry out closed loop adjustment through current regulator ACR1, ACR2 separately, output is given as the additional given and idle vector shaft voltage of meritorious vector shaft voltage; The additional given electric voltage feed forward signal U that exports with PLL of meritorious vector shaft voltage
dStack is given as meritorious vector shaft voltage; It is given that the given process of the meritorious given and idle vector shaft voltage of vector shaft voltage vector revolution VD2 and 2/3 conversion obtain three-phase alternating voltage; Isolate amplifying element through pulse-width modulation PWM control and pulse again, the device for power switching work among the control AFER.
As shown in Figure 4, said INV principle of work is following: given according to calculating of test needs and setting active current
Given with reactive current
Detect INV three-phase alternating current signal, calculate active current actual value i through 3/2 conversion and vector revolution VD3
OPAnd reactive current actual value i
OQActive current is given
With active current actual value i
OP, reactive current is given
With reactive current actual value i
OQRespectively relatively after, carry out closed loop adjustment respectively through current regulator ACR3, ACR4 separately, output is given as the additional given and idle vector shaft voltage of meritorious vector shaft voltage; The additional given electric voltage feed forward signal Ud stack with PLL output of meritorious vector shaft voltage is given as meritorious vector shaft voltage; It is given that the given process of the meritorious given and idle vector shaft voltage of vector shaft voltage vector revolution VD4 and 2/3 conversion obtain the INV three-phase alternating voltage; Isolate amplifying element through control of pulsewidth modulation (PWM) and pulse again, the device for power switching work among the control INV.
In the frequency converter topology, AFER adopts two closed-loop controls of DC voltage outer shroud and current inner loop, and INV adopts current closed-loop to control, can realize DC bus-bar voltage zero steady state error control, gain merit and the zero steady state error control of reactive power.When the INV active current given
(or reactive current is given
) need to be provided with by test, in the time of dynamically DC voltage is changed, the two closed loop adjustment controls through AFER DC voltage outer shroud and current inner loop keep DC bus-bar voltage stable, the active current i that AFER flows through when making stable state
IP(or reactive current i
IQ) and INV active current i
OP(or reactive current i
OQ) equate opposite, form meritorious (or idle) power circuit through T1 → AFER → INV → T2 → T1 closed-loop path.
The method of described flexible transducer power and output power factor size is: calculate the active current
under the various service conditions and when reactive current
makes
as
according to active power, the reactive power of test needs, active power and reactive power from electric power network through T1 → AFER → INV → T2 → T1 closed-loop path forward flow; During as
; Active power from electric power network through T1 → AFER → INV → T2 → T1 closed-loop path forward flow, reactive power from electric power network through T1 → AFER → INV → T2 → T1 closed-loop path reversed flow; During as
, active power and reactive power from electric power network through T1 → AFER → INV → T2 → T1 closed-loop path reversed flow; During as
; Active power from electric power network through T1 → AFER → INV → T2 → T1 closed-loop path reversed flow, reactive power from electric power network through T1 → AFER → INV → T2 → T1 closed-loop path forward flow.Therefore, through the method for the utility model, can realize the reversible operation test of active front end voltage-type ac-dc-ac frequency converter.
The temperature rise of power device and the operating condition of frequency converter, power factor are closely related; The temperature rise of the power device under declared working condition under the different capacity factor accurately simulated and tested to the test unit of the utility model can according to test needs flexible power and power factor.For the influence of transducer power factor to the power device temperature rise is described, current flowing path when being the work of example analysis frequency converter with the diode clamp three-level inverter below and the loss situation on each power device.Fig. 5 has provided a phase voltage first-harmonic u and the situation of change of this phase current first-harmonic i in one-period of inverter output, and
is power-factor angle.Situation according to voltage, current zero-crossing point among the figure can be divided into four intervals with the whole cycle and analyze respectively:
1, interval
Current path as Fig. 6 a) shown in.This interval u is for just, and i is for negative.Because width modulation, actual AC side voltage is just, switch between zero.V1 and V3 alternate conduction, V2 is in conducting state always.When AC side voltage positive status, electric current flows into direct current positive bus through D1, D2; When AC side voltage zero state, electric current flows into zero dc bus through V3, D6.In said process, almost there is not electric current to flow through among the V1, loss is very little; The existing conduction loss of V3 also has switching loss; Sustained diode 1, D2 flow through electric current when conducting, have conduction loss; D1 bears back-pressure when turn-offing, have reverse recovery loss, and D2 when turn-offing because V2 and V3 are open-minded, do not bear back-pressure, do not have reverse recovery loss.
2, interval
Current path is like Fig. 6 b) shown in.This interval u is being for just, and i is for just.Because width modulation, actual AC side voltage is just, switch between zero.V1 and V3 alternate conduction, V2 is in conducting state always.When AC side voltage positive status, electric current flows out through V1, V2; When AC side voltage zero state, electric current flows out through V2, D5.With interval 1) analysis classes seemingly, the existing conduction loss of V1 this moment also has switching loss, there is conduction loss in V2; D5 bears back-pressure when turn-offing, have reverse recovery loss.
3, interval
Current path is like Fig. 6 c) shown in.This interval u is for negative, and i is for just.Because width modulation, actual AC side voltage is in negative, switching between zero.V2 and V4 take turns conducting, and V3 is in conducting state always.When AC side voltage negative state, electric current flows out through D3, D4; When AC side voltage zero state, electric current flows out through V2, D5.This interval, the V2 pipe exists conduction loss and switching loss; The D3 pipe has conduction loss; D4 manages existing conduction loss has reverse recovery loss again.
4, interval
Current path is like Fig. 6 d) shown in.This interval u is for negative, and i is for negative.Because width modulation, actual AC side voltage is in negative, switching between zero.V2 and V4 take turns conducting, and V3 is in conducting state always.When AC side voltage negative state, electric current flows into the direct current negative busbar through V3, V4; When AC side voltage zero state, electric current flows into through V3, D6.In this interval, V3, V4 flow through electric current when conducting, have conduction loss; V4 is because also there is switching loss in switch motion; There is reverse recovery loss in D6.
Above-mentioned analysis shows, during the work of voltage-type ac-dc-ac frequency converter, the size, time that flows through electric current in the power device and AC side power factor, voltage magnitude are relevant, so the temperature rise of device is also relevant with power factor.Therefore, adopt the test unit of the utility model, through regulating the power factor of inverter output, can loss and the temperature rise of full test frequency converter under various operating modes, and then the accurate specified fan-out capability of apparatus for evaluating under the different capacity factor.
This test unit carries out the rated capacity test to active front end voltage-type ac-dc-ac frequency converter and may further comprise the steps:
Step 1: with reference to Fig. 1; Active front end voltage-type ac-dc-ac frequency converter is connected to electric power network through transformer T1, T2 and switch S 1, S2 (or, active front end voltage-type ac-dc-ac frequency converter is connected to electric power network through transformer T and switch S with reference to Fig. 2; Or, active front end voltage-type ac-dc-ac frequency converter is connected to electric power network through transformer T1, reactor TD and switch S 1, S2) with reference to Fig. 3.
Step 2: make up control system with reference to Fig. 4.
Step 3: after calculating active current
and reactive current
power supply under each service condition and close a floodgate according to the power of test needs and power factor; When making
as
, active power and reactive power from electric power network through T1 → AFER → INV → T2 → T1 closed-loop path forward flow; During as
; Active power from electric power network through T1 → AFER → INV → T2 → T1 closed-loop path forward flow, reactive power from electric power network through T1 → AFER → INV → T2 → T1 closed-loop path reversed flow; During as
, active power and reactive power from electric power network through T1 → AFER → INV → T2 → T1 closed-loop path reversed flow; During as
; Active power from electric power network through T1 → AFER → INV → T2 → T1 closed-loop path reversed flow, reactive power from electric power network through T1 → AFER → INV → T2 → T1 closed-loop path forward flow.
In process of the test; Change active current
as required and reactive current
is given; Measure the temperature rise of each power device under each operating mode; According to the permission temperature rise of measurement result and each power device, confirm the rated power that frequency converter allows under the different capacity factor.
It is emphasized that; The described embodiment of the utility model is illustrative; Rather than it is determinate; Therefore the utility model is not limited to the embodiment described in the embodiment, every by those skilled in the art according to other embodiments that the technical scheme of the utility model draws, belong to the scope of the utility model protection equally.
Claims (6)
1. the rated capacity test unit of an active front end voltage-type ac-dc-ac frequency converter; It is characterized in that: comprise frequency converter, device for transformer and electric power network; The active front-end rectifier AFER of frequency converter and inverter INV insert electric power network through device for transformer respectively; Through regulating the size of relevant given flexible transducer power of AFER and output power factor with INV; Carry out the reversible operation test of rated capacity under the different capacity factor, a whole set of frequency converter rated capacity and power device temperature rise are tested.
2. by the rated capacity test unit of the described active front end voltage-type ac-dc-ac frequency converter of claim 1, it is characterized in that: described active front end voltage-type ac-dc-ac frequency converter mainly is made up of active front-end rectifier AFER, inverter INV and dc filter capacitor.
3. press the rated capacity test unit of the described active front end voltage-type ac-dc-ac frequency converter of claim 1; It is characterized in that: described device for transformer is transformer T1 and transformer T2, and the active front-end rectifier AFER of frequency converter and inverter INV insert electric power network through transformer T1 and transformer T2 respectively; Perhaps described device for transformer is one two cracking transformer T, and the active front-end rectifier AFER of frequency converter and inverter INV insert electric power network through two cracking transformer T respectively; Perhaps described device for transformer is transformer T1 and reactor TD, and the active front-end rectifier AFER of frequency converter and inverter INV insert electric power network through transformer T1 and reactor TD respectively.
4. by the rated capacity test unit of the described active front end voltage-type ac-dc-ac frequency converter of claim 1, it is characterized in that: described active front-end rectifier AFER and inverter INV all adopt active power and the control of reactive power independent vector.
5. by the rated capacity test unit of the described active front end voltage-type ac-dc-ac frequency converter of claim 1, it is characterized in that: the reactive current active current given, inverter INV of the described relevant given AFER of comprising is given and reactive current is given.
6. press the rated capacity test unit of the described active front end voltage-type ac-dc-ac frequency converter of claim 1; It is characterized in that: described active front-end rectifier AFER is two circuit structures that topology is identical with inverter INV, and DC side links to each other back-to-back through filter capacitor and constitutes active front end voltage-type ac-dc-ac frequency converter.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN2011204296891U CN202281807U (en) | 2011-11-03 | 2011-11-03 | Rated capacity test device of active front end voltage type AC-DC-AC frequency converter |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN2011204296891U CN202281807U (en) | 2011-11-03 | 2011-11-03 | Rated capacity test device of active front end voltage type AC-DC-AC frequency converter |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN202281807U true CN202281807U (en) | 2012-06-20 |
Family
ID=46227970
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| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN2011204296891U Withdrawn - After Issue CN202281807U (en) | 2011-11-03 | 2011-11-03 | Rated capacity test device of active front end voltage type AC-DC-AC frequency converter |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN202281807U (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102393495A (en) * | 2011-11-03 | 2012-03-28 | 天津电气传动设计研究所 | Rated-capacity test device for active front-end voltage type AC-DC-AC frequency converter |
-
2011
- 2011-11-03 CN CN2011204296891U patent/CN202281807U/en not_active Withdrawn - After Issue
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102393495A (en) * | 2011-11-03 | 2012-03-28 | 天津电气传动设计研究所 | Rated-capacity test device for active front-end voltage type AC-DC-AC frequency converter |
| CN102393495B (en) * | 2011-11-03 | 2014-07-02 | 天津电气传动设计研究所 | Rated-capacity test device for active front-end voltage type AC-DC-AC frequency converter |
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|---|---|---|---|
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| GR01 | Patent grant | ||
| AV01 | Patent right actively abandoned |
Granted publication date: 20120620 Effective date of abandoning: 20140702 |
|
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