CN1285168C - Controller for inverter device - Google Patents
Controller for inverter device Download PDFInfo
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- CN1285168C CN1285168C CNB2004100070392A CN200410007039A CN1285168C CN 1285168 C CN1285168 C CN 1285168C CN B2004100070392 A CNB2004100070392 A CN B2004100070392A CN 200410007039 A CN200410007039 A CN 200410007039A CN 1285168 C CN1285168 C CN 1285168C
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- voltage
- motor
- control device
- imbalance
- converter
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- E—FIXED CONSTRUCTIONS
- E05—LOCKS; KEYS; WINDOW OR DOOR FITTINGS; SAFES
- E05B—LOCKS; ACCESSORIES THEREFOR; HANDCUFFS
- E05B1/00—Knobs or handles for wings; Knobs, handles, or press buttons for locks or latches on wings
- E05B1/0061—Knobs or handles with protective cover, buffer or shock absorber
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- Control Of Ac Motors In General (AREA)
- Inverter Devices (AREA)
Abstract
A control apparatus for inverters is provided to suppress a chattering in an output voltage of an inverter portion by raising an output voltage when a chattering is detected in a chattering state detector. A control apparatus(4) for inverters(1) having a DC(Direct Current) voltage as an input and operates an AC(Alternating Current) motor as a load. The control apparatus includes a driving signal calculator(43), a voltage detector, and a chattering state detector(42). The driving signal calculator calculates a driving signal for an inverter portion(41) which converts a DC source to a variable frequency-variable voltage AC voltage. The voltage detector detects the DC voltage. The chattering state detector detects a chattering state of the AC motor from a magnitude of a pulsation included in the detected DC voltage.
Description
Technical field
After the present invention relates to a kind of alternating voltage that dc voltage conversion is become variable frequency, variable voltage, the control device of the inverter of variable speed drive alternating current motor (inverter).
Background technology
When utilizing DC-to-AC converter to drive alternating current motor, interaction owing to the impedance (impedance) of applied voltage distortion that idle time of PWM (puleswidth modulation) signal that drives inverter part, (dead time) caused and alternating current motor and moment of inertia etc. occurs current waveform sometimes and periodically vibrates this what is called " detuning phenomena ".This phenomenon.Especially at large-scale alternating current motor, and in low load, low-frequency band, take place quite frequently.
After this imbalance took place, vibration will appear in alternating current motor itself, during serious vibration, its running can't be proceeded.As the method that suppresses this detuning phenomena, it is the error of proofreading and correct the output voltage that causes idle time of the inverter pwm signal that causes the one of the main reasons that occurs lacking of proper care that kind of method is arranged.As its example, following routine method is by public affairs all and many (consulting non-patent literature 1).
This method is provided with the current sensor (sensor) of the electric current that detects alternating current motor, and the current phase of the alternating current motor that arrives according to this current sensor senses is proofreaied and correct the inverter pwm signal, thereby suppresses the distortion of applied voltage.With this generation that suppresses to lack of proper care, suppress the vibration of alternating current motor.
In addition, as detecting, suppress the another kind of method that imbalance takes place, following method also make known publicly (consulting patent documentation 1).This method is being provided with and is detecting inflow by the current sensor 103 of the current value of inverter part 101 compressor driven 102 of DC-to-AC converter as shown in figure 12.Interchange portion imbalance judging part 104 according to the rate of change of these current sensor 103 detected electric currents, is judged the state of imbalance.Conclude that at interchange portion imbalance judging part 104 when being the imbalance state, just action of output voltage alteration command portion 105 increases voltage instruction value.Then, waveform operational part 106 is obtained required pwm pulse width according to output voltage values and output frequency command value from output voltage alteration command portion 105, drives inverter part 101.Utilize this structure, suppress the imbalance of compressor 102 and the generation of vibration.
[non-patent literature 1] Nikkan Kogyo Shimbun periodical " 512 pages of handbook of inverter driver (inverter drive) " dead time correction method "
[patent documentation 1] spy opens flat 10-23789 communique ([0018], Fig. 1)
, adopt the method for above-mentioned non-patent literature 1, though can suppress imbalance by proofreading and correct the voltage distortion that causes idle time, existing needs current sensor, causes the DC-to-AC converter volume to become problem big, cost up.
In addition, adopt the method for patent documentation 1, existing too needs current sensor (sensor), brings the problem of the increase of the maximization of device and cost; In addition, as current sensor, when using resistance, also there are and need operational amplifier (Amplifier), increase the quantity of parts, the problem that device volume is increased; And, adopt this structure after, also have the influence be subjected to power supply voltage variation, be difficult to the accurately problem of control.
Summary of the invention
The present invention will solve this problem that prior art exists, and its objective is provides and can go out the imbalance situation with simple structure detection, and can reliably control the control device of the DC-to-AC converter of imbalance.
DC-to-AC converter, input direct voltage is with the alternating current motor of AC energy supply as load.Control device as this DC-to-AC converter, the present invention carries out at the alternating voltage of computing and output needle subtend variable frequency variable voltage also having: the voltage detecting parts that detect described direct voltage outside the drive signal arithmetic unit of drive signal of inverter part of conversion; With size, detect the imbalance state-detection parts of the imbalance state of described alternating current motor according to the contained ripple component of detected direct voltage.Utilize this imbalance state-detection parts, when detecting the imbalance state, described drive signal arithmetic unit is proofreaied and correct described drive signal, so that improve the output voltage of described inverter part.
After adopting said structure, the generation that can suppress to lack of proper care reduces the vibration of alternating current motor, the control device of the alternating current motor that provide simple in structure, cheap, reliability is high.
The invention of the present invention's 1 record in control device, outside the drive signal arithmetic unit, also comprises: the voltage detecting parts that detect described direct voltage; With size, detect the imbalance state-detection parts of the imbalance state of described alternating current motor according to the contained ripple component of detected direct voltage.When detecting the imbalance state, the output voltage of described inverter part is risen, thereby suppress imbalance, the effect of the control device of the alternating current motor that obtain to provide simple in structure, cheap, reliability is high.
The invention of the present invention's 4 records in control device, outside the drive signal arithmetic unit, also comprises: the voltage detecting parts that detect described direct voltage; With in order to control the imbalance state of described alternating current motor, and preestablish and store the output voltage memory unit of required output voltage values.When change appears in the value of the direct voltage that detects, output preestablishes and is stored in the output voltage values of output in the memory unit, can obtain to provide cheap, structure and control effect simple, the control device of high and strong interference immunity, alternating current motor that reliability is high for the stability of variation in voltage.
Description of drawings
Fig. 1 is the frame assumption diagram that adopts the control device that the 1st execution mode of the present invention relates to.
Fig. 2 is the figure of the both end voltage waveform of expression current waveform of inflow motor 2 and electrolytic capacitor 3d.
Fig. 3 is the figure of the both end voltage waveform of expression current waveform of inflow motor 2 and electrolytic capacitor 3d.
Fig. 4 is the frame assumption diagram that adopts the control device that the 2nd execution mode of the present invention relates to.
Fig. 5 is the figure of the both end voltage waveform of expression current waveform of inflow motor 2 and electrolytic capacitor 3h.
Fig. 6 is the figure of the both end voltage waveform of expression current waveform of inflow motor 2 and electrolytic capacitor 3h.
Fig. 7 is the frame assumption diagram that adopts the control device that the 3rd execution mode of the present invention relates to.
Fig. 8 is the frame assumption diagram of alternate manner in expression the 3rd execution mode.
Fig. 9 is the frame assumption diagram that adopts the control device that the 4th execution mode of the present invention relates to.
Figure 10 is the frame assumption diagram of alternate manner in expression the 4th execution mode.
The flow chart of the action of the control device of Figure 11 presentation graphs 1.
Figure 12 is the frame assumption diagram of control device of the alternating current motor of expression prior art.
Among the figure: 1-inverter part; 2-motor; 3-DC power supply; 3a-single phase alternating current power supply; 3b-reactor; 3c-single-phase diode electric bridge; 3d-electrolytic capacitor; 3e-three-phase alternating-current supply; 3f-three-phase diode bridge; 3g-reactor; 3h-electrolytic capacitor; 4-control device; 41-A/D converter; 42-imbalance state-detection portion; 43-drive signal operational part; 44-output voltage storage part; 45-direct current mean value operational part.
Embodiment
Below, consult accompanying drawing, tell about embodiments of the present invention.
(the 1st execution mode)
Fig. 1 is a frame assumption diagram of using the DC-to-AC converter of the control device 4 that the 1st execution mode relates to.In Fig. 1, inverter part 1 is made of a plurality of switches (switching) element, the alternating voltage of output variable frequency, variable voltage.As the 3 phase motor that the output with inverter part 1 drives, be widely used induction motor and synchronous motor etc.DC power supply 3, power supply is supplied with described inverter part 1, here, it is by reactor (reactor) 3b, with electrolytic capacitor (condenser) 3d, to what the level and smooth back of acquisition pulsating current voltage after the 3c full-wave rectification of single phase alternating current power supply 3a process diode bridge (diode bridge) was realized.
Control device 4, by the output voltage with DC power supply 3 be transformed into A/D (Analog-Digital) converter 41 of digital signal, according to constituting from the imbalance state-detection portion 42 of the imbalance state of the size detection alternating current motor of the contained ripple component of A/D converter 41 signals and the drive signal operational part 43 that calculates the pwm signal that drives inverter part 1.
After this imbalance state-detection portion 42 detects imbalance, drive signal operational part 43 is sent the signal of the applied voltage rising 1 grade (step) that will supply with motor 2.This imbalance state-detection portion 42 and drive signal operational part 43 use microcomputer (microcomputer) to realize.In addition, generate the drive signal operational part 43 of pwm signal, adopt well-known structure, so no longer describe in detail.
Below, tell about the action of the DC-to-AC converter of Fig. 1.In the output voltage (both end voltage of electrolytic capacitor 3d) of the DC power supply 3 that after with single phase alternating current power supply 3a full-wave rectification, is obtained, comprise the alternating component (below be called " ripple (ripple) voltage ") of 2 times frequency content of ac power frequency.The pulsating current voltage waveform that the both end voltage of the current waveform of inflow motor 2 and electrolytic capacitor 3d is contained, as shown in Figure 2.As shown in Figure 2, when the frequency of AC power 3a was 50Hz, the terminal voltage of electrolytic capacitor 3d contained the ripple voltage of 100Hz.
The current waveform of the electric current of inflow motor 2 and the pulsating current voltage waveform of electrolytic capacitor 3d when Fig. 3 is the 2 generation imbalances of expression motor.As shown in Figure 3, the both end voltage of the electrolytic capacitor 3d when imbalance takes place becomes on the ripple voltage of 100Hz, and stack owing to lack of proper care produces results from the pulsating current voltage waveform of pulsating current composition of low frequency of current waveform distortion of motor 2.
So, by detection the pulsating current voltage composition of the contained low frequency of the both end voltage that do not have this electrolytic capacitor 3d is arranged, just can detect whether occur imbalance in the motor 2.Below, the flow chart (flow chart) of use Figure 11 describes the situation that imbalance state-detection portion 42 is detected and control is lacked of proper care and taken place in detail.
At first, in step S1, be 0 with n value initialization.In step S2, according to the signal that A/D converter 41 obtains, obtain the data during the 10ms, this 10ms is 1 cycle (1000ms/100) in the ripple voltage of 100Hz.At step S3, from these data that obtain, detect and store maximum (Vppmax) and minimum value (Vppmin).
At step S4, with value increase (increment) 1 of n; Do you at step S5, judge that the value of n becomes 10? value at n became before 10, carried out the flow process (flow) of step S2～step S4 repeatedly.Value at n becomes at 10 o'clock, promptly carry out the flow process of 10 step S2～step S4 repeatedly, to during 100mS (10mS * 10 time), detected data are chosen maximum Vppmax.max and minimum value Vppmin.min again from detected 10 maximum Vppmax.Equally, from detected 10 minimum value Vppmin, choose maximum Vppmax.max and minimum value Vppmin.min again.
During the judgement imbalance, the pulsating current that is decided to be the low frequency that is produced by imbalance for example is decided to be 100mS (count value (count) that is about to n is decided to be 10) more than the cycle.But be not limited thereto.
In step S7, calculate the maximum of Vppmax and poor (Vppmax.max-Vppmax.min) of minimum value, or poor (Vppmin.max-Vppmin.min) of the maximum of Vppmin and minimum value; In step S7, judge that in these differences any one is whether in institute more than the definite value.
When these differ from less than institute's definite value, conclude imbalance to occur, return step S1, carry out above-mentioned action once more repeatedly.When these differ from greater than institute's definite value, conclude and imbalance occurred, to drive signal operational part 43 send the applied voltage that will supply with motor 2 improve 1 grade fixed control signal, thereby at step S8, correction is from the pwm signal of drive signal operational part 43, by the voltage of 1 grade of inverter part 1 output rising.
, return step S1, carry out the control of above-mentioned steps S1～step S7 repeatedly thereafter.At this moment, if interrupt making having showed imbalance, just in step S8, applied voltage is risen 1 grade again at step S7.Till this imbalance is suppressed, carry out the control of step S1～step S8 repeatedly.
Its result, after the imbalance of motor 2 was suppressed, the both end voltage waveform of the current waveform of motor 2 and electrolytic capacitor just became state shown in Figure 2, and in this state, motor 2 remains in operation.
Like this, behind the control device of the alternating current motor of employing present embodiment, can use simple structure, detect the generation of imbalance, and it is suppressed reliably, reduce the vibration of alternating current motor 2.So the enough simple structures of energy reduce the vibration of alternating current motor 2, the control device of the alternating current motor that generator is simple in structure, reliability is high conscientiously.
(the 2nd execution mode)
Fig. 4 is the frame assumption diagram that adopts the DC-to-AC converter of the control device 4 that the 2nd execution mode relates to.Compared to Figure 1, difference is to adopt the structure that is obtained DC power supply by 3 cross streams power supply 3e.In Fig. 4, DC power supply 3 is to utilize reactor 3f and electrolytic capacitor 3h, will realize by the level and smooth back of the pulsating current voltage after diode bridge (diode bridge) the 3g full-wave rectification.
Fig. 5 illustrates when imbalance not occurring, the both end voltage waveform of the current waveform of inflow motor 2 and electrolytic capacitor 3h.Compare with Fig. 2, as can be known: power supply is 3 phase times, by with after the selected suitable value of reactor 3f, just has ripple voltage hardly.
Fig. 6 illustrates when imbalance occurring, the both end voltage waveform of the current waveform of inflow motor 2 and electrolytic capacitor 3h.At this moment, also the same with Fig. 3, become the arteries and veins stream voltage waveform of pulsating current composition of the low frequency of superimposed the current waveform distortion that results from the motor 2 that imbalance causes.
In the DC-to-AC converter of Fig. 4, the control device 4 that also adopts the 2nd enforcement to relate to.Chat with the 1st execution mode and like that, detect imbalance whether occurs, if detect imbalance, just with 1 grade of the applied voltage rising of motor 2.
This control device 4 of Fig. 4, basic identical with the control device of Fig. 1.But in the DC-to-AC converter of Fig. 4, because as shown in Figure 5, in VD, do not contain ripple voltage,, promptly do not need and to be fixed into 10mS during the acquisition of the data among the step S2 of Figure 11 so do not need to make the sense cycle of direct voltage to equate with the ripple cycle.
In this DC-to-AC converter, the same during also with the 1st execution mode, can imbalance occur with simple structure detection, and be controlled reliably, so can reduce the vibration of motor 2.
(the 3rd execution mode)
Fig. 7 is the frame assumption diagram that adopts the DC-to-AC converter of the control device 4 that the 3rd execution mode relates to, replace the imbalance state-detection portion 41 among Fig. 1, be provided with output voltage storage part 44, and, the direct voltage detection signal is sent into drive signal operational part 43 by A/D converter 41.Output voltage storage part 44 is the output voltage values that preestablish, store inverter part 1 essential inverter part 1 for the imbalance state of controlling motor 2.
Below, tell about the control action of the DC-to-AC converter of Fig. 7.Drive signal operational part 43, according to detected dc voltage value and output voltage storage part 44 set, the output voltage values of storage, calculate pwm signal to inverter part 1 output.
Here, after the magnitude of voltage of single phase alternating current power supply 3a descended, the dc voltage value of DC power supply 3 also will descend.Drive signal operational part 43 is proofreaied and correct pwm signal, strengthens its function (tuty), so that the output voltage values that inverter part 1 is set to motor 2 output output voltage storage parts 44 all the time.In addition, otherwise when the dc voltage value of DC power supply 3 also will rise, drive signal operational part 43 was proofreaied and correct pwm signal, reduces its function, so that the voltage of inverter part 1 output is equated with the set point of output voltage storage part 44.
Its result because what give all the time that motor 2 adds is the voltage that does not occur lacking of proper care, so can not be subjected to the influence of the change of DC power supply 3, suppresses the generation of imbalance all the time.
The DC-to-AC converter of Fig. 8, the same with Fig. 4, be that the expression AC power is the frame assumption diagram of 3 phase times, at this moment also can pass through the operation the same, the appearance of control imbalance with the DC-to-AC converter of Fig. 7.
In sum, adopt the control device of alternating current motor of the 3rd execution mode after, can be irrelevant with the change of direct voltage, utilize simple structure and control, the generation of control imbalance reduces the vibration of motor 2 conscientiously.So also can when power supply changes, utilize simple structure and control, reduce the vibration of motor 2 conscientiously, the structure of generator, control simple and easy, strong interference immunity, the control device of the alternating current motor that reliability is high.
(the 4th execution mode)
Fig. 9 is square frame (block) structure chart that adopts the DC-to-AC converter of the control device that the 4th execution mode relates to, and compares with the structure of Fig. 7, has appended direct current mean value operational part 45.It is fixed moment detect the direct voltage of DC power supply 3, calculate the mean value of detected M up-to-date data, supply with drive signal operational part 43.Control content in drive signal operational part 43, identical with the situation of Fig. 9, but after setting up direct current mean value operational part 45, but have following advantage:
When imbalance occurring, as shown in Figure 3, the dc voltage value of DC power supply 3, on ripple voltage superposition result from the pulsating voltage of low frequency of current waveform distortion.To this, direct current mean value operational part 45 calculates than resulting from the mean value of the dc voltage value that repeated detection arrives in long time low-frequency cycle of this imbalance.In other words, the mean value execution cycle that makes dc voltage value is greater than resulting from pulsation period of low frequency of imbalance.
Its result, even maximum Vppmax.max shown in the 1st execution mode and minimum value Vppmax.min's is poor, or the difference of maximum Vppmin.max and minimum value Vppmax.min is in institute below the definite value, even promptly low frequency pulsating also has some when remaining, also can stably detect the current/voltage value, so can more effectively the output voltage of inverter be corrected into the value of output voltage storage part 44 settings, carry out stable action.
The DC-to-AC converter of Figure 10 is with the frame assumption diagram of AC power among Fig. 9 as three phase times, at this moment, also can adopt the control identical with Fig. 9, control imbalance stably.
In sum, adopt the 4th execution mode after, can be irrelevant with the change of direct voltage, utilize simple structure and control, the generation of control imbalance stably reduces the vibration of motor 2 conscientiously.So during power supply voltage variation, also can utilize simple structure and control, conscientiously stably reduce the vibration of motor 2, the structure of generator, control are simple and easy, strong interference immunity, the controller for ac motor that reliability is high.
Claims (2)
1, a kind of control device of DC-to-AC converter, be with direct voltage as input, with the control device of alternating current motor, it is characterized in that as the DC-to-AC converter of load:
Described control device outside the drive signal arithmetic unit of the drive signal of the inverter part of the AC voltage conversion of computing and output needle subtend variable frequency variable voltage, also has: the voltage detecting parts that detect described direct voltage; With in order to control the imbalance state of described alternating current motor, and preestablish and store the output voltage memory unit of required output voltage values,
When change appearred in the value of the direct voltage that detects, described drive signal arithmetic unit was proofreaied and correct described drive signal, made described inverter part export the output voltage values that preestablishes and be stored in the output voltage memory unit.
2, the control device of DC-to-AC converter as claimed in claim 1 is characterized in that: also have the fixed moment obtain the voltage that detects with described voltage detecting parts, and obtain the direct current mean value arithmetic unit of the up-to-date M that obtains mean value.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2003274034 | 2003-07-14 | ||
| JP2003274034A JP3748560B2 (en) | 2003-07-14 | 2003-07-14 | Inverter control device |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN1578109A CN1578109A (en) | 2005-02-09 |
| CN1285168C true CN1285168C (en) | 2006-11-15 |
Family
ID=34211104
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CNB2004100070392A Expired - Fee Related CN1285168C (en) | 2003-07-14 | 2004-02-26 | Controller for inverter device |
Country Status (3)
| Country | Link |
|---|---|
| JP (1) | JP3748560B2 (en) |
| KR (1) | KR20050008455A (en) |
| CN (1) | CN1285168C (en) |
Families Citing this family (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN100438322C (en) * | 2005-06-13 | 2008-11-26 | 吴彦颉 | Voltage modulation device for controlling electric vehicle motor |
| JP6388542B2 (en) * | 2015-01-06 | 2018-09-12 | 三菱電機株式会社 | Motor control device |
| DE102015107934A1 (en) * | 2015-05-20 | 2016-11-24 | Voith Patent Gmbh | Variable speed drive system and method for starting and / or operating a speed changeable drive system |
| JP6912038B2 (en) * | 2017-07-07 | 2021-07-28 | 日本電産サーボ株式会社 | Motor drive, blower, motor drive method, and recording medium |
| KR102213601B1 (en) | 2018-12-06 | 2021-02-08 | 현대오트론 주식회사 | Method of charging battery for on board charger and system performing the same |
-
2003
- 2003-07-14 JP JP2003274034A patent/JP3748560B2/en not_active Expired - Fee Related
-
2004
- 2004-02-09 KR KR1020040008288A patent/KR20050008455A/en not_active Application Discontinuation
- 2004-02-26 CN CNB2004100070392A patent/CN1285168C/en not_active Expired - Fee Related
Also Published As
| Publication number | Publication date |
|---|---|
| KR20050008455A (en) | 2005-01-21 |
| CN1578109A (en) | 2005-02-09 |
| JP3748560B2 (en) | 2006-02-22 |
| JP2005039930A (en) | 2005-02-10 |
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Granted publication date: 20061115 Termination date: 20140226 |