CN105301391A - Island detection device and island detection method based on active filtering and harmonic compensation - Google Patents

Island detection device and island detection method based on active filtering and harmonic compensation Download PDF

Info

Publication number
CN105301391A
CN105301391A CN201510676070.3A CN201510676070A CN105301391A CN 105301391 A CN105301391 A CN 105301391A CN 201510676070 A CN201510676070 A CN 201510676070A CN 105301391 A CN105301391 A CN 105301391A
Authority
CN
China
Prior art keywords
harmonic
current
active
active filter
load
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.)
Granted
Application number
CN201510676070.3A
Other languages
Chinese (zh)
Other versions
CN105301391B (en
Inventor
冬雷
韩劲草
黄晓江
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Mao Guoquan
Original Assignee
BEIJING DONGLI JINGGONG TECHNOLOGY Co Ltd
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by BEIJING DONGLI JINGGONG TECHNOLOGY Co Ltd filed Critical BEIJING DONGLI JINGGONG TECHNOLOGY Co Ltd
Priority to CN201510676070.3A priority Critical patent/CN105301391B/en
Publication of CN105301391A publication Critical patent/CN105301391A/en
Application granted granted Critical
Publication of CN105301391B publication Critical patent/CN105301391B/en
Active legal-status Critical Current
Anticipated expiration legal-status Critical

Links

Classifications

    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
    • Y02E40/00—Technologies for an efficient electrical power generation, transmission or distribution
    • Y02E40/40—Arrangements for reducing harmonics

Landscapes

  • Supply And Distribution Of Alternating Current (AREA)

Abstract

The invention discloses an island detection device and an island detection method based on active filtering and harmonic compensation. The detection device comprises an active filtering device, a three-phase grid-connected inverter and a nonlinear load. According to the invention, harmonic waves generated by the nonlinear load are compensated by using the active electric power filtering device so as to improve the quality of electric energy, the compensation rate of compensating current is changed periodically, then the compensating current of the active electric power filtering device is used as the disturbance quantity of an injection system, the compensating current of the active electric power filtering device and voltage of a point of common coupling are acquired so as to calculate equivalent impedance looking towards the system from a port of the active electric power filtering device, and whether an island effect occurs or not is detected through judging variation conditions of the impedance, so that island detection can be completed quickly while improving the quality of electric energy of the system.

Description

Based on isolated island detecting device and the method for active power filtering and harmonic compensation
Technical field
The present invention relates to a kind of isolated island detecting device based on active power filtering and harmonic compensation and method, belong to micro-capacitance sensor fault detect and power quality controlling application.
Background technology
In order to the renewable new forms of energy solving global energy problem such as wind energy, sun power and so on are widely applied, distributed power generation is developed rapidly.Distributed generation system is normally operated in and net state, but when electrical network is due to the reason such as electric fault, maloperation interruption of power supply, distributed generation system just defines power supply isolated island, this can bring very serious problem to the safe operation of electric system, even can jeopardize the personal safety of plant maintenance personnel.In addition, the widespread use of the nonlinear loads such as power electronic equipment can produce a large amount of harmonic waves, the control strategy of distributed generation system not only can be made to become very complicated, also can have a strong impact on power grid quality.Therefore, the island state detecting distributed generation system when not reducing power grid quality is rapidly and accurately needed.
Patent 1: based on the distributed generator islanding detection method of impedance measurement, application number 201010210918.0, the invention provides a kind of island detection method, comprise the following steps: A, to connecting an impedance inject high-frequency voltage signal to grid-connected contact point between distributed power source with main electrical network; B, according to voltage divider principle, Computation distribution formula power supply and main electrical network grid-connected time system equiva lent impedance on voltage effective value; The voltage effective value of C, the in real time grid-connected contact point of measurement, when voltage effective value increases suddenly certain multiple, is judged to island effect occurs.
Patent 2: island effect detection system when a kind of dual harmonic electric current injects simultaneously and method, application number 201310261192.7, the method that inventing provides injects the harmonic current of 25Hz and 100Hz two type, calculated the harmonic impedance under two kinds of frequencies by the harmonic voltage detecting the two kinds of frequencies in point of common coupling place, judge whether island effect occurs according to the change of impedance.
Although island effect can be detected by the change of impedance in above-mentioned patent, owing to being additionally filled with some signals in electrical network, power grid quality is inevitably affected.If when system load is nonlinear load, the quality of power supply of system can be very poor, and extra Injection Signal can aggravate the deterioration of the quality of power supply.
Summary of the invention
The present invention is directed to the problem existing for prior art, propose a kind of isolated island detecting device based on active power filtering and harmonic compensation and method.The harmonic wave that fundamental purpose is produced by the load of active electric filter device compensating non-linear, using the disturbance quantity of the offset current of active electric filter device as injected system, the offset current of active electric filter device and the voltage of point of common coupling (PCC) is utilized to calculate from the equiva lent impedance to system viewed from active electric filter device port, by judging the situation of change of impedance detects whether island effect occurs, and can complete islanding detect rapidly like this while the quality of power supply improving system.
The object of the present invention is achieved like this:
The present invention proposes a kind of isolated island detecting device based on active power filtering and harmonic compensation, it is characterized in that, comprise active filter, distributed power generation unit, nonlinear load, three phase network, output current sensor, load current sensor, power network current sensor and point of common coupling voltage sensor; Three phase network is connected to after active filter, distributed power generation unit and nonlinear load parallel connection; Output current sensor is connected to active filter output terminal; Load current sensor is connected with nonlinear load; Power network current sensor and point of common coupling voltage sensor are connected to the output terminal of three phase network, and nonlinear load comprises three-phase uncontrollable rectifier bridge and coupled inductive load and ohmic load.
The present invention proposes a kind of island detection method based on active power filtering and harmonic compensation, specifically comprises the following steps:
A, output current sensor, load current sensor, power network current sensor and point of common coupling voltage sensor is utilized to gather respective physical amount;
B, calculating harmonic current;
C, to arrange cancellation ratio K be different values, sends offset current by active filter according to cancellation ratio and harmonic current;
D, respectively discrete Fourier transformation is done to the offset current of point of common coupling voltage and active filter, obtain the component under h subharmonic;
E, calculate the equiva lent impedance of active filter port according to the electric current and voltage gauge of two adjacent power frequency periods, the circuit expressions formula in adjacent two cycles is as shown in formula (1) (2);
Vpcc 1 Z s / / Z D G / / Z L = K 1 I c - I h s - I h D G - I h L - - - ( 1 )
Vpcc 2 Z s / / Z D G / / Z L = K 2 I c - I h s - I h D G - I h L - - - ( 2 )
In formula, V pcc1and V pcc2represent the PCC point voltage in continuous two cycles respectively, K 1and K 2represent the harmonic compensation rate in two cycles respectively.Z sthe impedance of grid side Equivalent Harmonic, I hDGand Z dGthe h subharmonic current that sends of DG system and Equivalent Harmonic impedance respectively, I hLand Z lharmonic current and the impedance of nonlinear load equivalence respectively, I hcthe h subharmonic current that under expression non-ideality, electrical network produces, I coffset current when be the cancellation ratio of active filter being 1;
F, asked the equiva lent impedance Z of active filter port by formula (1) (2) nN ', as shown in formula (3);
Z NN ′ = Z s / / Z DG / / Z L = Vpcc 1 - Vpcc 2 K 1 I c - K 2 I c = ΔVpcc Δ I c - - - ( 3 )
In formula, Δ V pccrepresent the variable quantity of point of common coupling voltage, Δ I csee the disturbance quantity of injected system as, i.e. the offset current variable quantity of active filter;
In G, system cloud gray model, if the Z calculated nN 'lower than threshold value Z set, then step D, E, F is repeated; If the Z obtained nN 'increase to and exceed threshold value Z set, then decision-making system generation island effect.
The method calculating harmonic current in above-mentioned steps B is the i based on three-phase instantaneous reactive power theory p-i qharmonic detection.
Because technique scheme is used, the present invention compared with prior art has following advantages and effect:
An effect of the present invention is, the harmonic wave that the load of using active filter compensating non-linear produces, and can improve the quality of power supply of system while completing islanding detect.
An effect of the present invention is, utilizes the electric current and voltage variable quantity of adjacent two power frequency periods to carry out islanding detect, and only need can detect island effect slightly larger than the time of a power frequency period, detection time is short.
Accompanying drawing explanation
Fig. 1 is the isolated island detecting device topological diagram based on active power filtering and harmonic compensation in the present invention;
Fig. 2 is the one phase equivalent model of system under h subharmonic in the present invention;
Fig. 3 is a kind of island detection method process flow diagram based on active power filtering and harmonic compensation of the present invention;
Fig. 4 (a) is power network current oscillogram before harmonic compensation in the present invention;
Fig. 4 (b) is power network current oscillogram after harmonic compensation in the present invention;
Fig. 5 is the testing result oscillogram of the island detection method based on active power filtering and harmonic compensation proposed in the present invention.
In accompanying drawing, the parts representated by each label: 1, active filter 2, distributed power generation unit 3, nonlinear load 4, three phase network 5, output current sensor 6, load current sensor 7, power network current sensor 8, point of common coupling voltage sensor 9, three-phase uncontrollable rectifier bridge 10, inductive load 11, ohmic load.
Embodiment
Embodiment:
A kind of isolated island detecting device based on active power filtering and harmonic compensation, it is characterized in that, comprise active filter (1), distributed power generation unit (2), nonlinear load (3), three phase network (4), output current sensor (5), load current sensor (6), power network current sensor (7) and point of common coupling voltage sensor (8); Output terminal and the point of common coupling PCC (12) of three phase network (4) is connected to after active filter (1), distributed power generation unit (2) and nonlinear load (3) parallel connection; Output current sensor (5) is connected to active filter (1) output terminal; Load current sensor (6) is connected with nonlinear load (3); Power network current sensor (7) and point of common coupling voltage sensor (8) are connected to the output terminal of three phase network (4).Described nonlinear load (3) comprise three-phase uncontrollable rectifier bridge (9) and be connected inductive load (10) and ohmic load (11).
Based on the island detection method of active power filtering and harmonic compensation, by detecting power network current, load current and the point of common coupling voltage in electric system, and then the harmonic component extracted in electrical network, active filter is utilized to carry out harmonic compensation to promote the quality of power supply, the cancellation ratio of periodic variation harmonic compensation can calculate the port Impedance of active filter, if isolated island occurs, port Impedance can have greatly changed and exceed the threshold value of setting, thus judges to there occurs island effect.Detection method example is as follows:
Based on active power filtering and harmonic compensation isolated island detecting device topological diagram as shown in Figure 1, the present invention establishes the one phase equivalent model under its h subharmonic, as shown in Figure 2.Employing model is the main control chip of DSP as active filter of TMS320F28335.Fig. 3 be the embodiment of the present invention provide a kind of based on active power filtering and the isolated island detecting device of harmonic compensation and the process flow diagram of method.Mainly comprise the steps:
A, output current sensor (5), load current sensor (6), power network current sensor (7) and point of common coupling voltage sensor (8) is utilized to gather respective physical amount;
B, calculating harmonic current, active filter (1) carries out the power network current before harmonic compensation as shown in Fig. 4 (a);
C, to arrange harmonic compensation rate K be with the parameter of primitive period alternately change, sends offset current by active filter (1) according to cancellation ratio and harmonic current; After active filter (1) compensates, power network current is as shown in Fig. 4 (b), and active filter (1) has carried out effectively compensating to the harmonic wave in electrical network.
D, to point of common coupling PCC (12) voltage V pccwith the offset current (I of active filter (1) c) do discrete Fourier transformation respectively, obtain the component under each harmonic;
E, calculate the equiva lent impedance of active filter (1) port according to the electric current and voltage gauge of two adjacent power frequency periods, the circuit expressions formula in adjacent two cycles is as shown in formula (1) (2);
Vpcc 1 Z s / / Z D G / / Z L = K 1 I c - I h s - I h D G - I h L - - - ( 1 )
Vpcc 2 Z s / / Z D G / / Z L = K 2 I c - I h s - I h D G - I h L - - - ( 2 )
In formula, V pcc1and V pcc2represent PCC (12) voltage in continuous two cycles respectively, K 1and K 2represent the harmonic compensation rate in two cycles respectively, Z sthe impedance of grid side Equivalent Harmonic, I hDGand Z dGthe h subharmonic current that sends of DG system and Equivalent Harmonic impedance respectively, I hLand Z lharmonic current and the impedance of nonlinear load (3) equivalence respectively, I hcthe h subharmonic current that under expression non-ideality, electrical network (4) produces, I coffset current when be the cancellation ratio of active filter (1) being 1;
F, asked the equiva lent impedance Z of active filter (1) port by formula (1) (2) nN ', as shown in formula (3);
Z NN ′ = Z s / / Z D G / / Z L = Vpcc 1 - Vpcc 2 K 1 I c - K 2 I c = Δ V p c c ΔI c - - - ( 3 )
Δ V in formula pccrepresent the variable quantity of point of common coupling (12) voltage, Δ I cit is the output current variable quantity of active filter (1);
G, threshold value Z is set setif, the Z calculated nN 'lower than threshold value Z set, then repeat step D, E, F, islanding detect signal is low level; If the Z obtained nN 'increase to more than Z set, then decision-making system generation island effect, islanding detect signal becomes high level; Figure 5 shows that testing result oscillogram when there is isolated island, detection time is slightly larger than a power frequency period.
The above embodiment of the present invention can find out the offset current computing impedance owing to utilizing active filter, can also improve the quality of power supply of system while therefore completing islanding detect fast.
The foregoing is only preferred embodiment of the present invention, not in order to limit the present invention, within the spirit and principles in the present invention all, any amendment done, equivalent replacement, improvement etc., all should be included in protection scope of the present invention.

Claims (4)

1., based on an isolated island detecting device for active power filtering and harmonic compensation, comprise active filter (1), distributed power generation unit (2), nonlinear load (3), three phase network (4), output current sensor (5), load current sensor (6), power network current sensor (7) and point of common coupling voltage sensor (8); Output terminal and the point of common coupling PCC (12) of three phase network (4) is connected to after described active filter (1), distributed power generation unit (2) and nonlinear load (3) parallel connection, output current sensor (5) is connected to active filter (1) output terminal, load current sensor (6) is connected with nonlinear load (3), and power network current sensor (7) and point of common coupling voltage sensor (8) are connected to the output terminal of three phase network (4).
2. a kind of isolated island detecting device based on active power filtering and harmonic compensation as claimed in claim 1, it is characterized in that, nonlinear load (3) comprises three-phase uncontrollable rectifier bridge (9) and coupled inductive load (10) and ohmic load (11).
3., based on an island detection method for active power filtering and harmonic compensation, it is characterized in that, described island detection method comprises the following steps:
Steps A: utilize output current sensor (5), load current sensor (6), power network current sensor (7) and point of common coupling voltage sensor (8) to gather respective physical amount;
Step B: calculate harmonic current;
Step C: arranging cancellation ratio K is different values, sends offset current by active filter (1) according to cancellation ratio and harmonic current;
Step D: to point of common coupling voltage V pccwith the offset current I of active filter (1) cdo discrete Fourier transformation respectively, obtain the component under h subharmonic;
Step e: the equiva lent impedance calculating active filter (1) port according to the electric current and voltage gauge of two adjacent power frequency periods, the circuit expressions formula in adjacent two cycles is as shown in formula (1) (2);
Vpcc 1 Z s / / Z D G / / Z L = K 1 I c - I h s - I h D G - I h L - - - ( 1 )
Vpcc 2 Z s / / Z D G / / Z L = K 2 I C - I h s - I h D G - I h L - - - ( 2 )
In formula, and V pcc2represent the PCC point voltage in continuous two cycles respectively, K 1and K 2represent the harmonic compensation rate in two cycles respectively.Z sthe impedance of grid side Equivalent Harmonic, I hDGand Z dGthe h subharmonic current that sends of DG system and Equivalent Harmonic impedance respectively, I hLand Z lharmonic current and the impedance of nonlinear load (3) equivalence respectively, I hcthe h subharmonic current that under expression non-ideality, electrical network produces, I coffset current when be the cancellation ratio of active filter (1) being 1;
Step F: the equiva lent impedance Z being asked active filter (1) port by formula (1) (2) nN ', as shown in formula (3);
Z NN ′ = Z s / / Z D G / / Z L = Vpcc 1 - Vpcc 2 K 1 I c - K 2 I c = Δ V p c c ΔI c - - - ( 3 )
Δ V in formula pccrepresent the variable quantity of point of common coupling voltage, Δ I csee the disturbance quantity of injected system as, i.e. the offset current variable quantity of active filter (1);
Step G: in system cloud gray model, if the Z calculated nN 'lower than threshold value Z set, then step D, E, F is repeated; If the Z obtained nN 'increase to and exceed threshold value Z set, then decision-making system generation island effect;
4. a kind of island detection method based on active power filtering and harmonic compensation as claimed in claim 3, is characterized in that, the method calculating harmonic current in step B is the i based on three-phase instantaneous reactive power theory p-i qharmonic detection.
CN201510676070.3A 2015-10-20 2015-10-20 Isolated island detecting device and method based on active power filtering and harmonic compensation Active CN105301391B (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN201510676070.3A CN105301391B (en) 2015-10-20 2015-10-20 Isolated island detecting device and method based on active power filtering and harmonic compensation

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN201510676070.3A CN105301391B (en) 2015-10-20 2015-10-20 Isolated island detecting device and method based on active power filtering and harmonic compensation

Publications (2)

Publication Number Publication Date
CN105301391A true CN105301391A (en) 2016-02-03
CN105301391B CN105301391B (en) 2019-03-29

Family

ID=55198888

Family Applications (1)

Application Number Title Priority Date Filing Date
CN201510676070.3A Active CN105301391B (en) 2015-10-20 2015-10-20 Isolated island detecting device and method based on active power filtering and harmonic compensation

Country Status (1)

Country Link
CN (1) CN105301391B (en)

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN107271786A (en) * 2017-07-20 2017-10-20 西安科技大学 Island detection method based on harmonic impedance dq components
CN108594046A (en) * 2018-06-04 2018-09-28 西安科技大学 Island detection method based on comprehensive impedance fundametal compoment
CN108680825A (en) * 2018-05-18 2018-10-19 西安科技大学 A kind of island detection method based on synthetic sequence impedance
CN109075577A (en) * 2016-02-11 2018-12-21 智能电线股份有限公司 Use the control of distributed impedances injection module and actuator device to electric system in power grid

Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN101697418A (en) * 2009-10-23 2010-04-21 湖南大学 Photovoltaic inversion grid-connection and harmonic suppression hybrid system for micro grid and composite control method thereof
CN103117553A (en) * 2012-09-17 2013-05-22 湖南工业大学 Novel power quality regulator on background of micro-grid
CN103427419A (en) * 2013-08-22 2013-12-04 宁波中睿电气有限公司 Active power filter selective harmonic compensation control method
CN103983873A (en) * 2014-05-19 2014-08-13 国网宁夏电力公司 Island detection method suitable for multi-inverter parallel operation and based on impedance measurement
CN104377699A (en) * 2014-11-13 2015-02-25 湖南大学 Hybrid induction type active power filter and reactive compensation system and method for wind power plant
CN104600748A (en) * 2015-02-04 2015-05-06 国家电网公司 Island microgrid multi-inverter control system with active filtering function and working method thereof

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN101697418A (en) * 2009-10-23 2010-04-21 湖南大学 Photovoltaic inversion grid-connection and harmonic suppression hybrid system for micro grid and composite control method thereof
CN103117553A (en) * 2012-09-17 2013-05-22 湖南工业大学 Novel power quality regulator on background of micro-grid
CN103427419A (en) * 2013-08-22 2013-12-04 宁波中睿电气有限公司 Active power filter selective harmonic compensation control method
CN103983873A (en) * 2014-05-19 2014-08-13 国网宁夏电力公司 Island detection method suitable for multi-inverter parallel operation and based on impedance measurement
CN104377699A (en) * 2014-11-13 2015-02-25 湖南大学 Hybrid induction type active power filter and reactive compensation system and method for wind power plant
CN104600748A (en) * 2015-02-04 2015-05-06 国家电网公司 Island microgrid multi-inverter control system with active filtering function and working method thereof

Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN109075577A (en) * 2016-02-11 2018-12-21 智能电线股份有限公司 Use the control of distributed impedances injection module and actuator device to electric system in power grid
CN107271786A (en) * 2017-07-20 2017-10-20 西安科技大学 Island detection method based on harmonic impedance dq components
CN108680825A (en) * 2018-05-18 2018-10-19 西安科技大学 A kind of island detection method based on synthetic sequence impedance
CN108680825B (en) * 2018-05-18 2020-09-01 西安科技大学 Island detection method based on comprehensive sequence impedance
CN108594046A (en) * 2018-06-04 2018-09-28 西安科技大学 Island detection method based on comprehensive impedance fundametal compoment
CN108594046B (en) * 2018-06-04 2020-11-24 西安科技大学 Island detection method based on comprehensive impedance fundamental component

Also Published As

Publication number Publication date
CN105301391B (en) 2019-03-29

Similar Documents

Publication Publication Date Title
CN103944507B (en) Photovoltaic-power-station low-voltage penetrating performance evaluation method based on inverter model test
CN203688720U (en) Fault detection system for DC transmission grounding electrode circuits
CN105301391A (en) Island detection device and island detection method based on active filtering and harmonic compensation
CN104267315B (en) Based on the composite type island detection method that intentional frequency offset and voltage magnitude change
CN103308806B (en) Islanding detection method based on fundamental frequency and switching-frequency sub-impedance
CN103259472B (en) The antihunt Adaptive Suppression system of Generator Set sub-synchronous oscillation
CN103760434A (en) Self-adaption phase deviation island detection method based on fuzzy control
CN104993501A (en) On-line evaluation method of low-frequency oscillation suppression performance of excitation regulator
CN105334390A (en) External centralized disturbance type impedance measurement island detection method suitable for multimachine cluster
CN105182189A (en) Inverter disturbance type island detection method based on combination of voltage frequency and measured impedance
CN104360235A (en) Method for positioning voltage sag source of complex power distribution network including DGs
CN104950202A (en) Island detection method and system based on reactive power-frequency positive feedback
CN104104251B (en) A kind of robust control method of the combining inverter based on SSR-KDF
Singh et al. Power Quality Issues of Electric Arc Furnace and their Mitigations-A Review
CN102981061B (en) Direct-to-ground capacitance measuring instrument in a kind of transformer station distribution system
CN112803478A (en) Active injection type single-end protection method for micro-grid based on phase polarity characteristics
CN103675560B (en) The on-line identification method of a kind of HVDC (High Voltage Direct Current) transmission system wave filter on DC side off resonance
CN108258702B (en) It is a kind of meter and transmission line of electricity distribution capacity grid-connected inverter resonance suppressing method
CN103577698A (en) On-line voltage stability judging method for alternating current and direct current series-parallel system
CN107104463B (en) Converter station considers idle active input amount optimization method during black starting-up
CN103078347B (en) Impact load bearing method for reducing voltage limit risk
CN105186544A (en) Subsynchronous oscillation inhibition method and device based on UPFC, and power generating system
CN106533238A (en) Voltage compensation-based grid-connected inverter control method for marine electrical system
CN105467252A (en) Three-phase photovoltaic inverter active anti-islanding method based on reactive power disturbance
CN103050990A (en) Distributed power generation system for carrying out island detection by adopting wavelet transformation

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
TR01 Transfer of patent right
TR01 Transfer of patent right

Effective date of registration: 20211208

Address after: 646000 Room 601, 6 / F, unit 1, building 5, No. 76, longtouguan Road, Jiangyang District, Luzhou City, Sichuan Province

Patentee after: Mao Guoquan

Address before: 100083 4-203, building 9, yard 7, Fengqiao Road, Fengtai District, Beijing

Patentee before: BEIJING POWER KINGKONG TECHNOLOGY CO.,LTD.