CN104682432B - The relay failure detection and filter capacitor guard method of photovoltaic combining inverter - Google Patents
The relay failure detection and filter capacitor guard method of photovoltaic combining inverter Download PDFInfo
- Publication number
- CN104682432B CN104682432B CN201510090419.5A CN201510090419A CN104682432B CN 104682432 B CN104682432 B CN 104682432B CN 201510090419 A CN201510090419 A CN 201510090419A CN 104682432 B CN104682432 B CN 104682432B
- Authority
- CN
- China
- Prior art keywords
- relay
- inverter
- voltage
- grid
- filter capacitor
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
Classifications
-
- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02J—CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY
- H02J3/00—Circuit arrangements for ac mains or ac distribution networks
- H02J3/38—Arrangements for parallely feeding a single network by two or more generators, converters or transformers
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R31/00—Arrangements for testing electric properties; Arrangements for locating electric faults; Arrangements for electrical testing characterised by what is being tested not provided for elsewhere
- G01R31/327—Testing of circuit interrupters, switches or circuit-breakers
-
- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02H—EMERGENCY PROTECTIVE CIRCUIT ARRANGEMENTS
- H02H9/00—Emergency protective circuit arrangements for limiting excess current or voltage without disconnection
- H02H9/02—Emergency protective circuit arrangements for limiting excess current or voltage without disconnection responsive to excess current
-
- 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
- Y02E10/00—Energy generation through renewable energy sources
- Y02E10/50—Photovoltaic [PV] energy
- Y02E10/56—Power conversion systems, e.g. maximum power point trackers
Abstract
The present invention relates to photovoltaic combining inverter technical field, and in particular to before the relay failure detection and filter capacitor guard method, including relay adhesive of photovoltaic combining inverter, detects a certain phase or multi-phase inverter voltage VinvVirtual value and same phase line voltage VgridThe difference of the absolute value of virtual value is less than relay failure voltage threshold Δ V, i.e., | Vinv‑Vgrid| ＜ Δ V, then the adhesion of this phase relay is judged, conversely, relay is normal；Similarly, sequentially pass through after adhesive inverter side relay test, adhesive grid side relay test, the detection of the equal adhesive of both sides relay, if each equal fault-free of step relay, allow it is grid-connected, it is not grid-connected if a wherein relay failure, shuts down.The present invention is while accurately detecting whether each relay fails, inverter output filter capacitor voltage is handled, the possibility that grid-connected inverters moment power network causes rush of current to filter capacitor is eliminated, inverter system stability is improved, extends the filter capacitor life-span.
Description
Technical field
The present invention relates to the relay failure of photovoltaic combining inverter technical field, more particularly to photovoltaic combining inverter
Detection and filter capacitor guard method.
Background technology
In a group string data photovoltaic combining inverter, small-power photovoltaic combining inverter field, two group relays are used
It is grid-connected.The relay test method generally used in industry is relay adhesive, grid-connected inverters moment, and inverter will not be filtered
Ripple electric capacity carries out charging process, so as to cause in grid-connected inverters moment, power grid energy moment pours into filter capacitor, and this can be to filter
Ripple electric capacity produces larger rush of current, and this is easy for causing the phenomenons such as filter capacitor failure, service life reduction.Particularly inverter
Power is larger, when filter capacitor capacity is larger, and this dash current, which results even in machine, normally to be started.
The content of the invention
To solve the above problems, the present invention provides relay failure detection and the filter capacitor of a kind of photovoltaic combining inverter
Guard method, while accurately detecting whether each relay fails, is carried out to inverter output filter capacitor voltage
Processing, eliminates the possibility that grid-connected inverters moment power network causes rush of current to filter capacitor, improves inverter system stable
Property, extend the filter capacitor life-span.
The present invention is adopted the following technical scheme that：The relay failure detection of photovoltaic combining inverter and filter capacitor protection side
Method, it is characterised in that comprise the following steps：(1) closing before any relay group, the voltage of inverter side is detected, as detected
A certain phase or multi-phase inverter voltage VinvVirtual value and same phase line voltage VgridVirtual value, relay failure voltage threshold Δ V expire
Foot：|Vinv-Vgrid| ＜ Δ V, then judge the phase relay adhesion, do not allow grid-connected inverters；Conversely, the phase relay
Normally；(2) step (1) detect relay it is normal when, open inverter, send with line voltage same-phase with amplitude
After inverter voltage, N number of power frequency period, after after inverter output filter capacitor Voltage Establishment, the relay group of inverter side is opened,
Continue to send the inverter voltage of above-mentioned N number of power frequency period, discharge the electric energy of filter capacitor, release detects inverter voltage after finishing
VinvVirtual value and same phase line voltage VgridThe difference of the absolute value of virtual value, meets when detecting a certain phase or ployphase voltages：|
Vinv-Vgrid|<Δ V, then judge the relay adhesion of the phase grid side, do not allow grid-connected inverters；Conversely, grid side relay
Normally；(3) step (2) detect grid side relay it is normal when, disconnect inverter side relay, open inverter, send
With inverter voltage of the line voltage same-phase with amplitude, after N number of power frequency period, inverter output filter capacitor Voltage Establishment is treated
Afterwards, the relay of grid side is opened, continues to send the inverter voltage of N number of power frequency period, discharges the electric energy of filter capacitor, release
Detection inverter voltage V after finishinginvVirtual value and same phase line voltage VgridThe difference of the absolute value of virtual value, when detecting a certain phase
Or multiphase is met：|Vinv-Vgrid|<Δ V, then judge the relay adhesion of the phase inverter side, do not allow grid-connected inverters；Instead
It, inverter side relay is normal；(4) step (3) detect grid side relay it is normal when, open inverter, send
With inverter voltage of the line voltage same-phase with amplitude, after N number of power frequency period, inverter output filter capacitor Voltage Establishment is treated
Afterwards, the relay of inverter side is opened, continues to send the inverter voltage of N number of power frequency period, detection inverter voltage VinvVirtual value with
With phase line voltage VgridThe difference of the absolute value of virtual value, meets when detecting a certain phase or multiphase：|Vinv-Vgrid|>Δ V, then
The phase relay not adhesive after open signal is received is able to conclude that, judges that mutually one of relay has failed, no
Allow grid-connected inverters；Conversely, then relay is normal, inverter starts grid-connected work.
Preferably, the relay failure voltage threshold Δ V is the limits of error caused by sampling.
Preferably, the relay failure voltage threshold Δ V is 15V.
Preferably, the N values are 4.
To being further improved to for above-mentioned technical proposal, the relay failure detection and filtering of the photovoltaic combining inverter
Electric capacity guard method, in addition to step (5), be specifically：After whole relay fault-frees, relay driving voltage, switching are opened
To energy saver mode.
Preferably, the method for the electric energy of the release filter capacitor is：The power tube of inverter is opened with certain sequential,
By the resistance formation loop on filter capacitor and circuit, so as to discharge the electric energy that filter capacitor is stored.
The relay failure detection and filter capacitor guard method of photovoltaic combining inverter of the present invention, compared to existing
The beneficial effect of technology is：
1st, this programme is carried out while effectively whether detection relay fails to inverter output filter capacitor voltage
Certain processing, eliminates possibility that grid-connected inverters moment power network causes rush of current to filter capacitor, improves inverter
The stability of a system, extends the filter capacitor life-span.
2nd, relay failure detection method is accurate, any one relay of energy detection and localization.
3rd, after relay fault-free, relay driving voltage is opened, that is, can guarantee that the reliable adhesive of relay, and can reduce
Relay is lost.
Brief description of the drawings
Fig. 1 is in the relay failure detection and filter capacitor guard method of photovoltaic combining inverter of the embodiment of the present invention three
The grid-connected schematic diagram of phase photovoltaic combining inverter；
Fig. 2 is single in the relay failure detection and filter capacitor guard method of photovoltaic combining inverter of the embodiment of the present invention
The grid-connected schematic diagram of phase photovoltaic combining inverter；
Relay failure detections and filter capacitor guard method relaying of the Fig. 3 for photovoltaic combining inverter of the embodiment of the present invention
Electrical equipment drive waveform and corresponding inverter voltage waveform；
Relay failure detections and filter capacitor guard method flow of the Fig. 4 for photovoltaic combining inverter of the embodiment of the present invention
Figure.
Embodiment
Below in conjunction with accompanying drawing, the present invention is further illustrated.
Embodiment：
Reference picture 1,4, the relay failure detection of photovoltaic combining inverter of the present invention and filter capacitor protection side
Method comprises the following steps：
By taking three-phase group string data photovoltaic synchronization inverter system as an example, as shown in figure 1, including tetra- parts of A, B, C, D, wherein
A is photovoltaic array source and inverter power module part, and for being sinusoidal PWM ripples by the inversion of photovoltaic array DC source, B is LC
Filtering system, the sine pulse width modulation (PWM) ripple for inverter to be exported is converted to sine wave, and C is grid-connected relay group, for inverter with
Power network sets up connection, and D is power network.L is the filter inductance of inverter, and C is the filter capacitor of inverter, and KM1, KM3, KM5 are inverse
Become device side relay group, KM2, KM4, KM6 are grid side relay group.
How grid-connected inverters moment introduced below, relay acts, and just can guarantee that the reliable and stable work of inverter system
Make, can accurately detect whether relay fails again, specific implementation step is as follows：
(1) close before any relay group, detect inverter side voltage, a certain phase such as detected or multi-phase inverter voltage
VinvVirtual value and same phase line voltage VgridThe difference of the absolute value of virtual value is less than relay failure voltage threshold Δ V, i.e., |
Vinv-Vgrid|<Δ V, then judge the adhesion of this phase relay, do not allow grid-connected inverters；
(2) after step (1) detection passes through, inverter is opened, is sent with line voltage same-phase with the inverse of amplitude
After time variant voltage, 4 power frequency periods, after after inverter output filter capacitor Voltage Establishment, the relay group of inverter side is opened, after
Supervention goes out the inverter voltage of 4 power frequency periods, is discharged filter capacitor electric energy by certain strategy, capacitive electric energy to be filtered is released
Put after end, detection inverter voltage VinvVirtual value and same phase line voltage VgridThe difference of the absolute value of virtual value, with step (1)
It is identical, when detecting a certain phase or multiphase | Vinv-Vgrid|<Δ V, then can determine that the relay adhesion of this phase grid side, no
Then, grid side relay is normal.If detecting grid side relay fault-free, inverter side relay is disconnected, and perform
(3) step detection process.
(3) it is identical with step (2), inverter is first turned on, the inversion electricity with amplitude with line voltage same-phase is sent
After pressure, 4 power frequency periods, after after inverter output filter capacitor Voltage Establishment, the relay of grid side is opened, continues to send 4
The inverter voltage of individual power frequency period, is discharged filter capacitor electric energy by certain strategy, and capacitive electric energy release to be filtered terminates
Afterwards, detection inverter voltage VinvVirtual value and same phase line voltage VgridThe difference of the absolute value of virtual value, when detect a certain phase or
Multiphase | Vinv-Vgrid|<Δ V, then can determine that the relay adhesion of this phase inverter side, and otherwise, inverter side relay is just
Normal.If detecting inverter side relay fault-free, (four) step detection process is performed.
(4) it is identical with (two) step, inverter is first turned on, the inversion electricity with amplitude with line voltage same-phase is sent
After pressure, 4 power frequency periods, after after inverter output filter capacitor Voltage Establishment, the relay of inverter side is opened, continues to send
The inverter voltage of 4 power frequency periods, grid side relay is not disconnected after judging inverter side relay fault-free in the third step
Device, therefore open inverter after inverter side relay here and establish and be connected with power network, detect inverter voltage VinvVirtual value with it is same
Phase line voltage VgridThe difference of the absolute value of virtual value, when detecting a certain phase or multiphase | Vinv-Vgrid|>Δ V, then be able to conclude that
The not adhesive after open signal is received of this phase relay, therefore may determine that this mutually one of relay has lost
Effect.If it is determined that condition is invalid, then relay is normal, and inverter starts grid-connected work, and whole relay test process arrives this
Terminate.
Wherein, the strategy of release filter capacitor electric energy is：The power tube of inverter is opened with certain sequential, by filtered electrical
Hold and form loop with the resistance on circuit, so as to discharge the electric energy that filter capacitor is stored.
The actuating of relay terminates, after fault-free, open relay driving voltage, switch to energy saver mode, that is, can guarantee that after
The reliable adhesive of electrical equipment, reduces the purpose of relay loss again.
Need exist for special instruction be a bit, the moment all closed in two group relays, inverter filtering electric capacity two ends
Exist with line voltage with voltage of the frequency with identical amplitude, therefore any impact will not have been produced to filter capacitor.
Above-mentioned relay failure voltage threshold Δ V is the limits of error caused by sampling, and Δ V=can be chosen for here
15V。
Inverter voltage waveforms of the Fig. 3 for relay driving waveform and in the same time, wherein most upper drive for inverter side relay
Dynamic waveform, high level is conducting, and low level is off state, and centre is grid side relay driving waveform, and bottom is correspondence
A certain phase inverter voltage waveform.
This method is equally applicable to two-phase, single-phase (Fig. 2) photovoltaic combining inverter, and method is identical with above-mentioned steps.
Embodiment described above only expresses the several embodiments of the present invention, and it describes more specific and detailed, but simultaneously
Therefore the limitation to the scope of the claims of the present invention can not be interpreted as.It should be pointed out that for one of ordinary skill in the art
For, without departing from the inventive concept of the premise, various modifications and improvements can be made, these belong to the guarantor of the present invention
Protect scope.Therefore, the protection domain of patent of the present invention should be determined by the appended claims.
Claims (4)
1. the relay failure detection and filter capacitor guard method of photovoltaic combining inverter, it is characterised in that including following step
Suddenly：
(1) close before any relay group, detect the voltage of inverter side, a certain phase such as detected or multi-phase inverter voltage
Vinv virtual values are met with same phase line voltage V grid virtual values, relay failure voltage threshold Δ V：|V inv-Vgrid|<
Δ V, then judge the phase relay adhesion, do not allow grid-connected inverters；Conversely, the phase relay is normal；
(2) step (1) detect relay it is normal when, open inverter, send with line voltage same-phase with amplitude
After inverter voltage, N number of power frequency period, after after inverter output filter capacitor Voltage Establishment, the relay group of inverter side is opened,
Continue to send the inverter voltage of above-mentioned N number of power frequency period, discharge the electric energy of filter capacitor, release detects inverter voltage after finishing
The difference of the absolute value of Vinv virtual values and same phase line voltage V grid virtual values, expires when detecting a certain phase or ployphase voltages
Foot：
|Vinv-Vgrid|<Δ V, then judge the relay adhesion of the phase grid side, do not allow grid-connected inverters；Conversely, power network
Side relay is normal；
(3) step (2) detect grid side relay it is normal when, disconnect inverter side relay, open inverter, send with
Line voltage same-phase with amplitude inverter voltage, after N number of power frequency period, after after inverter output filter capacitor Voltage Establishment,
The relay of grid side is opened, continues to send the inverter voltage of N number of power frequency period, discharges the electric energy of filter capacitor, release is finished
The difference of the absolute value of detection inverter voltage Vinv virtual values and same phase line voltage V grid virtual values afterwards, when detecting a certain phase
Or multiphase is met：|Vinv-Vgrid|<Δ V, then judge the relay adhesion of the phase inverter side, do not allow grid-connected inverters；
Conversely, inverter side relay is normal；
(4) step (3) detect grid side relay it is normal when, open inverter, send same with line voltage same-phase
After the inverter voltage of amplitude, N number of power frequency period, after after inverter output filter capacitor Voltage Establishment, open inverter side after
Electrical equipment, continues to send the inverter voltage of N number of power frequency period, detection inverter voltage Vinv virtual values and same phase line voltage V grid
The difference of the absolute value of virtual value, meets when detecting a certain phase or multiphase：|Vinv-Vgrid|>Δ V, then be able to conclude that this is successive
Electrical equipment not adhesive after open signal is received, judges that mutually one of relay has failed, does not allow grid-connected inverters；
Conversely, then relay is normal, inverter starts grid-connected work；
The relay failure voltage threshold Δ V=15V, 15V are the limits of error caused by sampling.
2. the relay failure detection and filter capacitor guard method of photovoltaic combining inverter according to claim 1, it is special
Levy and be：The N values are 4.
3. the relay failure detection and filter capacitor guard method of photovoltaic combining inverter according to claim 1, it is special
Levy and be：Also include step (5), be specifically：After whole relay fault-frees, relay driving voltage is opened, energy-conservation is switched to
Pattern.
4. the relay failure detection and filter capacitor guard method of photovoltaic combining inverter according to claim 1, it is special
Levy and be, the method for release filter capacitor electric energy is：The power tube of inverter is opened with certain sequential, by filter capacitor and line
Resistance formation loop on road, so as to discharge the electric energy that filter capacitor is stored.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201510090419.5A CN104682432B (en) | 2015-02-27 | 2015-02-27 | The relay failure detection and filter capacitor guard method of photovoltaic combining inverter |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201510090419.5A CN104682432B (en) | 2015-02-27 | 2015-02-27 | The relay failure detection and filter capacitor guard method of photovoltaic combining inverter |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN104682432A CN104682432A (en) | 2015-06-03 |
| CN104682432B true CN104682432B (en) | 2017-10-27 |
Family
ID=53317170
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201510090419.5A Active CN104682432B (en) | 2015-02-27 | 2015-02-27 | The relay failure detection and filter capacitor guard method of photovoltaic combining inverter |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN104682432B (en) |
Families Citing this family (27)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP6673036B2 (en) * | 2016-06-09 | 2020-03-25 | 住友電気工業株式会社 | Power conversion device and method of determining operation state of interrupting unit |
| CN106505628B (en) * | 2016-12-23 | 2019-04-09 | 阳光电源股份有限公司 | A kind of grid side hardware circuit Failure Control method and controller |
| CN107069686A (en) * | 2017-03-24 | 2017-08-18 | 江苏固德威电源科技股份有限公司 | Grid-connected moment impact current suppressing circuit and apply its photovoltaic inversion system |
| CN106932674B (en) * | 2017-04-11 | 2020-01-21 | 阳光电源股份有限公司 | Inverter output filter capacitor residual life prediction method and device and power generation system |
| CN107505533B (en) * | 2017-09-14 | 2020-11-10 | 爱士惟新能源技术(扬中)有限公司 | Live wire ground fault detection method and sampling signal processing method for grid-connected inverter |
| CN107968627A (en) * | 2017-11-14 | 2018-04-27 | 珠海格力电器股份有限公司 | Detection device and method and the non-isolation type photovoltaic system comprising the device |
| CN108363000B (en) * | 2018-01-23 | 2021-03-19 | 爱士惟新能源技术(扬中)有限公司 | Failure detection method for relay of inverter |
| CN108761319B (en) * | 2018-04-08 | 2020-08-28 | 阳光电源股份有限公司 | Relay failure detection method, device and system for photovoltaic grid-connected inverter |
| CN109066798B (en) * | 2018-09-17 | 2021-09-03 | 阳光电源股份有限公司 | Shutoff device of photovoltaic module |
| CN109490766A (en) * | 2018-10-12 | 2019-03-19 | 易事特集团股份有限公司 | The relay test method of light storage mixing inverter |
| CN109375099B (en) * | 2018-10-19 | 2020-10-02 | 爱士惟新能源技术(扬中)有限公司 | Fault detection method for grid-connected relay of photovoltaic inverter |
| CN109103979B (en) * | 2018-10-24 | 2023-11-10 | 珠海格力电器股份有限公司 | Photovoltaic electric equipment, charging control method and device thereof, circuit and storage medium |
| CN109946599B (en) * | 2019-03-28 | 2021-08-27 | 爱士惟新能源技术(江苏)有限公司 | Method and device for detecting relay before grid connection of photovoltaic three-phase inverter and storage medium |
| CN112924855B (en) * | 2019-12-06 | 2023-01-31 | 苏州阿特斯阳光电力科技有限公司 | Grid-connected relay circuit |
| CN111521928B (en) * | 2020-04-28 | 2023-03-31 | 阳光电源股份有限公司 | Grid-connected switch failure detection method and system of three-phase inverter |
| CN111864809B (en) * | 2020-07-31 | 2022-01-14 | 珠海银河耐吉科技股份有限公司 | Starting method of grid-connected inverter |
| CN112213631B (en) * | 2020-09-03 | 2021-11-09 | 珠海格力电器股份有限公司 | Relay state detection device and method and automobile |
| CN112415377B (en) * | 2021-01-21 | 2021-04-20 | 浙江艾罗网络能源技术股份有限公司 | Three-phase grid-connected inverter relay failure detection method |
| CN114977265A (en) | 2021-02-22 | 2022-08-30 | 华为数字能源技术有限公司 | Fault detection device and method and grid-connected photovoltaic power generation system |
| CN112986813B (en) * | 2021-03-05 | 2023-03-21 | 苏州海鹏科技有限公司 | Relay detection circuit and detection method of single-phase grid-connected photovoltaic inverter |
| CN113238146B (en) * | 2021-05-12 | 2022-05-24 | 阳光电源股份有限公司 | Neutral relay fault detection method and device of energy storage inverter system |
| CN113253108B (en) * | 2021-07-19 | 2021-09-24 | 浙江日风电气股份有限公司 | Three-phase relay detection method, device, equipment and computer readable storage medium |
| WO2023039775A1 (en) * | 2021-09-16 | 2023-03-23 | 华为数字能源技术有限公司 | Photovoltaic system, relay detection method, and power source system |
| CN115184838B (en) * | 2022-09-08 | 2023-01-31 | 深圳市云天数字能源有限公司 | Relay short circuit failure detection method and device |
| CN115166508B (en) * | 2022-09-08 | 2022-11-22 | 深圳市云天数字能源有限公司 | Failure detection method and relay failure detection device for grid-connected inverter |
| CN116165529B (en) * | 2022-12-20 | 2023-09-15 | 上海百竹成航新能源有限责任公司 | Relay adhesion detection method, electronic equipment and energy storage inverter system |
| CN117214690B (en) * | 2023-11-08 | 2024-04-09 | 深圳市首航新能源股份有限公司 | Relay adhesion detection method, electronic equipment and energy storage system |
Family Cites Families (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP2671315A2 (en) * | 2010-06-04 | 2013-12-11 | ABB Inc. | Detection of welded switch contacts in a line converter system |
| EP2667476B1 (en) * | 2011-01-20 | 2020-07-08 | Kabushiki Kaisha Toshiba | Photovoltaic system and power supply system |
-
2015
- 2015-02-27 CN CN201510090419.5A patent/CN104682432B/en active Active
Also Published As
| Publication number | Publication date |
|---|---|
| CN104682432A (en) | 2015-06-03 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN104682432B (en) | The relay failure detection and filter capacitor guard method of photovoltaic combining inverter | |
| US8259426B2 (en) | Variable frequency drive and methods for filter capacitor fault detection | |
| CN104300777B (en) | A kind of inverter synchronization combination method | |
| CN103066573B (en) | Modular multi-level multi-terminal flexible direct current system direct current fault handling method | |
| CN106357144B (en) | A kind of twin inverter topological structure opens fault of converter diagnosis and fault tolerant control method in winding electric machine drive system | |
| CN107957546A (en) | A kind of detection method and equipment of grid-connected inverters AC relay | |
| CN103499728B (en) | A kind of series capacitance unbalanced detection method of group voltage and system | |
| CN106849702B (en) | A kind of Novel rotary rectifier with malfunction monitoring function | |
| CN103944148A (en) | T-type three-level inverter protecting method and device and inverter circuit | |
| CN112803485B (en) | Photovoltaic rapid turn-off system and control method thereof | |
| CN104734581B (en) | Driving method for position-sensorless of permanent magnet brushless direct current motor | |
| CN103856067B (en) | A kind of frequency converter, work frequency variable synchronous handover control system and method | |
| CN102891503A (en) | Grid-connected startup method for photovoltaic grid-connected inverter | |
| CN105720831A (en) | Traction converter with double-voltage-sensor bus voltage detection circuit | |
| CN107154632B (en) | A kind of recognition methods of power unit by-pass state | |
| CN104283194B (en) | Circuit with failure protection function | |
| CN104993687B (en) | A kind of startup control method of combining inverter | |
| CN103178704A (en) | Peak current controlled power factor compensation circuit | |
| CN105322773B (en) | Soft-start circuit and its operating method | |
| CN204515032U (en) | A kind of proving installation of energy feedback unit | |
| CN103227560B (en) | Start the method and apparatus of inverter | |
| CN108445307A (en) | A kind of detection circuit and its detection method of electronic water pump electrical fault | |
| CN102780414A (en) | Device and method for inhibiting inrush starting current for large-power grid-connected inverter | |
| CN204179938U (en) | The synchronous grid-connected system of a kind of inverter | |
| CN102075126A (en) | Five-phase brushless direct-current motor control method having Hall fault-tolerance function |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C06 | Publication | ||
| PB01 | Publication | ||
| C10 | Entry into substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |