WO2017185223A1 - Système multiplexé de production d'énergie photovoltaïque du type en cascade, et appareil de production d'énergie photovoltaïque - Google Patents

Système multiplexé de production d'énergie photovoltaïque du type en cascade, et appareil de production d'énergie photovoltaïque Download PDF

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Publication number
WO2017185223A1
WO2017185223A1 PCT/CN2016/080193 CN2016080193W WO2017185223A1 WO 2017185223 A1 WO2017185223 A1 WO 2017185223A1 CN 2016080193 W CN2016080193 W CN 2016080193W WO 2017185223 A1 WO2017185223 A1 WO 2017185223A1
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Prior art keywords
power generation
photovoltaic
cascade
control unit
generation system
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PCT/CN2016/080193
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English (en)
Chinese (zh)
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胡炎申
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胡炎申
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Priority to CN201680003855.7A priority Critical patent/CN107112944A/zh
Priority to PCT/CN2016/080193 priority patent/WO2017185223A1/fr
Publication of WO2017185223A1 publication Critical patent/WO2017185223A1/fr

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    • 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
    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02S—GENERATION OF ELECTRIC POWER BY CONVERSION OF INFRARED RADIATION, VISIBLE LIGHT OR ULTRAVIOLET LIGHT, e.g. USING PHOTOVOLTAIC [PV] MODULES
    • H02S40/00—Components or accessories in combination with PV modules, not provided for in groups H02S10/00 - H02S30/00
    • H02S40/30—Electrical components
    • H02S40/36—Electrical components characterised by special electrical interconnection means between two or more PV modules, e.g. electrical module-to-module connection
    • H02J3/385—
    • 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

Definitions

  • the invention relates to the field of photovoltaic power generation, in particular to a multiplex cascade photovoltaic power generation system and a photovoltaic power generation device.
  • the photovoltaic module converts the solar light energy into intermittent and changing direct current, increases the voltage and increases the current through the series and parallel connection of the photovoltaic modules, and realizes the electrical connection function of the combiner box and the power distribution cabinet, and the photovoltaic inverter
  • the converter converts this randomly varying direct current into alternating current of the same frequency and phase as the utility grid.
  • the PV inverter has MPPT (Maximum Power Point Tracking) function, which can automatically find the maximum power point of the PV string or the PV array through an internal software algorithm.
  • Typical large-scale desert grounds and large-scale rooftop solar photovoltaic power plants generally use centralized inverters to form a photovoltaic power generation system, as shown in Figure 1, mainly consisting of solar photovoltaic cell modules, combiner boxes, AC and DC power distribution cabinets, and photovoltaic inverters. And the step-up transformer composition, can easily achieve 10kV/35kV medium voltage grid connection.
  • a plurality of photovoltaic modules are connected in series to form a photovoltaic string, and then a plurality of photovoltaic groups are connected in series to form a photovoltaic array, thereby obtaining a higher DC voltage and DC power, and then sharing a centralized inverter to realize grid-connected power generation.
  • the photovoltaic modules are connected in series to form a photovoltaic string, and the single or multiple parallel photovoltaic strings are boosted by independent DC/DC converters inside the string inverter, and then the string inverter is shared.
  • the same internal inverter circuit realizes grid-connected power generation, so this system architecture has
  • MPPT functions which partially improve the mismatch defects in the multiple series and parallel connection of the integrated system single MPPT.
  • FIG. 1 In order to eliminate the barrel effect of the centralized and string system, the concept of the power optimizer has been proposed in recent years, thus forming a photovoltaic power generation system including a power optimizer, as shown in FIG.
  • This system mainly adds a power optimizer component to the centralized and string-type photovoltaic power generation system, which brings the direct benefit of eliminating the barrel effect of the centralized and string system. Since each power module is equipped with a power optimizer on the back side, it is not necessary to directly connect the photovoltaic components in series to form a photovoltaic string, but the output of the power optimizer is connected in series, so that component level or distributed MPPT function can be realized. .
  • the power optimizer will increase the current system price by 6 to 7.5%; at the same time, its working efficiency is about 95 to 98%. Since the power optimizer keeps running during the photovoltaic system power generation, the system will increase the power loss by 2 to 5%.
  • micro-inverter photovoltaic power generation system proposed in recent years can also eliminate the barrel effect of centralized and string system, as shown in Figure 4.
  • This system is completely different from the centralized, string-type, and photovoltaic power generation system with power optimizer. It is not necessary to directly connect the PV modules in series to form a PV string, and a separate micro-inverter is installed on the back of each PV module. Therefore, component-level, or distributed MPPT functions can be implemented with the direct benefit of eliminating the barrel effect of centralized, string-based systems due to the series connection of components.
  • the DC voltage of the PV module is generally 30 ⁇ 36V, and the AC voltage of the grid is 110 ⁇ 220V. Therefore, the inside of the micro inverter is usually a two-stage structure.
  • the first stage realizes the DC boost function and the second stage completes the DC/AC AC inverter.
  • the problem caused by the two-stage structure is very obvious: on the one hand, the working efficiency of the micro-inverter is generally 95 to 96%, which results in an additional 4 to 5% power consumption of the photovoltaic power generation system; on the other hand, the internal components are numerous and the control is complicated.
  • the price is much higher than the integrated, string system structure, and higher than the system price of the power optimizer.
  • embodiments of the present invention provide a multiplexed cascade photovoltaic power generation system, which can eliminate the series connection of photovoltaic components by reconstructing the system architecture of the photovoltaic power generation technology.
  • the problem of the barrel effect that is easy to occur in the structure, and increase the power generation and work efficiency of the photovoltaic power generation system, while reducing the system cost.
  • a multiplexed cascade photovoltaic power generation system comprising at least one cascade subsystem, each of the cascade subsystems comprising a control unit and at least one power generation unit electrically connected to the control unit, the power generation unit including an output At least one or a plurality of distributed power generating units connected in series, the control unit being electrically connected to each of the distributed power generating units, each of the distributed power generating units connecting at least one photovoltaic component for using the photovoltaic
  • the DC voltage of the component is converted into an AC voltage, and the AC voltages outputted by the plurality of distributed power generating units are superposed in series to form a total output voltage, and the total output voltage is input to the control unit and integrated into the power grid through the control unit. Or output to an AC load.
  • the control unit includes a control, monitoring and communication module for transmitting control commands to each of the distributed power generation units, implementing coordinated cluster control of a plurality of the distributed power generation units, and monitoring the cascade The working state of the subsystem and the communication, protection and information processing of the cascade subsystem with the grid or AC load.
  • the multiplexed cascode type photovoltaic power generation system further includes a power filter circuit, and the power filter circuit is disposed in the control unit for realizing high frequency filtering of the total output voltage and current, and/or The power filter circuit is disposed in each of the distributed power generating units for realizing high frequency filtering of an alternating voltage and current output by each of the distributed power generating units.
  • the filter circuit is a symmetric LC filter circuit, or an asymmetric LC filter circuit, or an active filter circuit.
  • the distributed power generation unit includes a digital control chip and a DC/AC inverter circuit, and the digital control chip is electrically connected to the control unit and the DC/AC inverter circuit, and is configured to receive the control unit to send a control command, and generating a phase shift drive signal according to the control command to drive the DC/AC inverter circuit to convert a DC voltage of the photovoltaic module into an AC voltage through the DC/AC inverter circuit.
  • the topology of the DC/AC inverter circuit is a different structure such as an H-bridge, a Z-source H-bridge, a quasi-Z-source H-bridge, an I-type three-level, a T-type three-level or a module multi-level.
  • the distributed power generation unit further includes a DC/DC boost circuit connected between the photovoltaic component and the DC/AC inverter circuit for using the photovoltaic component The DC voltage is boosted.
  • the DC/DC boost circuit is a non-isolated Boost, Buck or Buck/Boost conversion circuit; or an isolated full-bridge, half-bridge, flyback, forward or push-pull conversion circuit.
  • the distributed power generation unit when connected to a plurality of photovoltaic modules, a plurality of the photovoltaic modules are connected to each other in series.
  • the multiplexed cascade photovoltaic power generation system includes a plurality of the cascaded subsystems, a plurality of the cascaded subsystems are connected in parallel with each other.
  • the multiplexed cascade photovoltaic power generation system is a three-phase neutral-line multiplex cascade photovoltaic power generation system, comprising three of the power generation units, each of the power generation units including n the distributions a power generation unit, the control unit includes a phase port, a b phase port, and a c phase port, wherein one end of each of the power generating units is electrically connected to an a phase port, a b phase port, and a c phase port of the control unit, respectively The other ends are electrically connected to each other.
  • the multiplexed cascade photovoltaic power generation system is a three-phase cascading photovoltaic power generation system having three neutral lines, including three said power generation units, each of said power generation units including n said distributions a power generation unit, the control unit includes a phase port, a b phase port, a c phase port, and a neutral port, wherein one end of each of the power generating units and the a phase port, the b phase port, and the c phase of the control unit respectively The ports are electrically connected, and the other ends are electrically connected to each other and to the neutral port.
  • a photovoltaic power generation device comprising: a multiplexed cascade photovoltaic power generation system, the multiple cascaded photovoltaic power generation system comprising at least one cascade subsystem, each of the cascade subsystems comprising a control unit and At least one power generating unit electrically connected to the control unit, the power generating unit string includes at least one, or a plurality of distributed power generating units outputted in series with each other, the control unit being electrically connected to each of the distributed power generating units Each of the distributed power generating units is connected to at least one photovoltaic component for converting a DC voltage of the photovoltaic component into an AC voltage, and the AC voltages outputted by the plurality of distributed power generating cells are stacked in series to form a total output voltage. The total output voltage is input to the control unit and integrated into the grid or output to the AC load through the control unit.
  • the photovoltaic power generation device is a photovoltaic grid-connected power generation device, a photovoltaic off-grid power generation device or a photovoltaic energy storage power generation device.
  • the multiplexed cascade photovoltaic power generation system connects at least one photovoltaic component through each of the distributed power generation units by providing a plurality of distributed power generation units connected in series with each other, since there is no need to directly connect the photovoltaic components in series, Component level or distributed MPPT functionality can be implemented Eliminate the barrel effect caused by the series connection of photovoltaic modules and increase the power generation of photovoltaic power generation systems.
  • the multiplexed cascade photovoltaic power generation system can reconstruct a photovoltaic power generation system structure, and each power generation unit can achieve higher working efficiency and use common AC cables, and at the same time remove conventional components such as a combiner box and a power optimizer, thereby reducing System price.
  • FIG. 1 is a schematic structural view of a photovoltaic power generation system constituting a centralized inverter in the prior art
  • FIG. 2 is a schematic structural view of a distributed photovoltaic power generation system formed by a string inverter in the prior art
  • FIG. 3 is a schematic structural view of a photovoltaic power generation system including a power optimizer in the prior art
  • FIG. 4 is a schematic structural view of a micro-inverter constituting a photovoltaic power generation system in the prior art
  • FIG. 5 is a schematic overall structural diagram of a multiplex cascade photovoltaic power generation system according to an embodiment of the present invention.
  • FIG. 6 is a schematic diagram of wiring of a multiple cascaded photovoltaic power generation system according to an embodiment of the present invention.
  • FIG. 7 is a schematic structural diagram of a power generating unit of a multiplexed cascade type photovoltaic power generation system according to an embodiment of the present invention.
  • FIG. 8 is a schematic structural diagram of a control unit of a multiplex cascade photovoltaic power generation system according to an embodiment of the present invention.
  • FIG. 9 is a schematic structural diagram of a multiplex cascade photovoltaic power generation system according to Embodiment 1 of the present invention.
  • FIG. 10 is a schematic diagram of a topological structure of a seven-level cascade inverter in a multiplex cascade photovoltaic power generation system according to an embodiment of the present invention
  • FIG. 11 is a schematic diagram of a square wave modulation waveform of a multiplexed cascade inverter in a multiplex cascade photovoltaic power generation system according to an embodiment of the present invention
  • FIG. 12 is a schematic structural diagram of a carrier phase shift modulation circuit of a multiplexed cascade inverter in a multiplex cascade photovoltaic power generation system according to an embodiment of the present invention
  • FIG. 13 is a schematic diagram of waveforms of carrier phase shift modulation of a multiplexed cascade inverter in a multiplex cascade photovoltaic power generation system according to an embodiment of the present invention
  • FIG. 14 is a seven-level cascade inverse in a multiplex cascade photovoltaic power generation system according to an embodiment of the present invention. Schematic diagram of the output voltage waveform of the transformer;
  • FIG. 15 is a schematic structural diagram of a multiplex cascade photovoltaic power generation system according to Embodiment 2 of the present invention.
  • FIG. 16 is a schematic structural diagram of a multiplex cascade photovoltaic power generation system according to Embodiment 3 of the present invention.
  • FIG. 17 is a schematic structural diagram of a multiplex cascade photovoltaic power generation system according to Embodiment 4 of the present invention.
  • FIG. 18 is a schematic structural diagram of a multiplex cascade photovoltaic power generation system according to Embodiment 5 of the present invention.
  • FIG. 19 is a schematic structural diagram of a multiplex cascade photovoltaic power generation system according to Embodiment 6 of the present invention.
  • FIG. 20 is a schematic structural diagram of a multiplex cascade photovoltaic power generation system according to Embodiment 7 of the present invention.
  • FIG. 21 is a schematic structural diagram of a multiplex cascade photovoltaic power generation system according to Embodiment 8 of the present invention.
  • FIG. 22 is a schematic structural diagram of a multiplex cascade photovoltaic power generation system according to Embodiment 9 of the present invention.
  • FIG. 23 is a schematic structural diagram of a multiplex cascade photovoltaic power generation system according to Embodiment 10 of the present invention.
  • a multiplexed cascade photovoltaic power generation system 100 including at least one cascade subsystem 110, each of which includes a control unit 111 and At least one power generating unit 113 electrically connected to the control unit, the power generating unit including one or more distributed power generating units 1131 outputted in series with each other, that is, the power generating unit 113 includes one of the distributed power generating units 1131, or
  • the power generation unit 113 includes a plurality of the distributed power generation units 1131, and outputs of the plurality of distributed power generation units 1131 are connected in series with each other, and the control unit 111 is electrically connected to each of the distributed power generating units 1131, and each of the distributed power generating units 1131 is connected to at least one photovoltaic component 1133 for converting a DC voltage of the photovoltaic modules 1133 into an AC voltage, and the plurality of The AC voltages output by the distributed power generation unit 1131 are superimposed in series to form a total
  • the multiplexed cascade photovoltaic power generation system is composed of a distributed power generation unit and a unified control unit.
  • One or more photovoltaic modules are installed with an independent distributed power generation unit, and the power generation unit can be integrated or externally connected to the photovoltaic junction box.
  • Internal or external, one or more power generating units have a unified control unit.
  • the system eliminates the need for direct connection of PV modules, enabling component-level, or Distributed Maximum Power Point Tracking (MPPT) functionality, eliminating the barrel effect caused by the series connection of PV modules.
  • MPPT Distributed Maximum Power Point Tracking
  • the power generation unit is mainly composed of a DC/AC inverter circuit, and its power conversion topology can be either a single-stage DC/AC circuit or a two-stage structure composed of a DC/AC circuit and a DC/DC circuit, DC/AC, DC.
  • the /DC circuit can use different converter topology types, such as H-bridge, Z-source and quasi-Z source inverter circuits, and DC buck-boost conversion circuits.
  • the output of each distributed power generation unit is AC low voltage, and the output end is cascaded to realize the multiplex cascade of AC voltages through the first and last series, so that the total output of the photovoltaic power generation system is a high AC voltage.
  • the power generation unit realizes the component-level MPPT technology and has independent distributed control functions, and accepts command control from the control unit cooperative cluster control signal, and reports related monitoring information, and the total output voltage of the distributed power generation unit output connected in series is also connected.
  • the control unit contains all the functions related to grid-related information collection, power generation, protocol conversion, grid-side filtering, active derating, reactive power compensation, harmonics management, and grid fault traversal, as well as the required completion of photovoltaic power generation systems. External communication, power generation status reporting and monitoring, control command uploading and dispatching, power grid dispatching, and security protection, and achieving coordinated cluster control, state collection, and calculation processing for each power generating unit.
  • the filter circuit inside the control unit can adopt different structural forms, such as symmetric and asymmetric LC filter circuits, and the filter circuit can also be installed inside the power generation unit to form a distributed filter structure.
  • Each of the distributed power generation units includes a power connection and a signal connection between the distributed power generation unit and the control unit, and the communication signal can be either a wired connection or a wireless connection. Therefore, the system structure can increase the power generation of the photovoltaic system, improve the system work efficiency, and reduce the overall price of the DC cable and the inverter.
  • each photovoltaic module is installed with An independent distributed power generation unit, in which the AC output sides of the plurality of distributed power generation units are connected in series and enter the control unit of the corresponding PV string to realize a higher single-phase AC voltage output.
  • a subsystem composed of a plurality of distributed power generation units and a unified control unit converts the direct current power of each photovoltaic string into an alternating current output, and the alternating current outputs of the plurality of multiple cascaded subsystems are connected in parallel to enter the alternating current power distribution cabinet and then access the alternating current.
  • the grid realizes grid-connected power generation.
  • the distributed power generating unit is mainly composed of a DC/AC inverter circuit, and the power conversion topology thereof can be either a single-stage DC/AC circuit or a DC/AC. And a two-stage structure composed of a DC/DC circuit, in which a component-level MPPT function is implemented by a DC/AC circuit in a single-stage conversion structure.
  • the distributed power generation unit includes a digital control chip and a DC/AC inverter circuit, and the digital control chip is electrically connected to the control unit and the DC/AC inverter circuit for receiving a control instruction sent by the control unit, and generating a phase shift driving signal according to the control command to drive the DC/AC inverter circuit to convert a DC voltage of the photovoltaic module into a DC/AC inverter circuit AC voltage.
  • the distributed power generation unit further includes a DC/DC boost circuit, and the two-stage conversion structure implements a component-level MPPT function by a DC/DC circuit.
  • the DC/DC boosting circuit is connected between the photovoltaic module and the DC/AC inverter circuit for performing a step-up process on a DC voltage output by the photovoltaic module.
  • a separate distributed power generation unit may be installed for each photovoltaic module, as shown in FIG. 6( a ), or two or more photovoltaic modules may be used.
  • An independent distributed power generation unit is installed in series to achieve the optimal cost performance of the system, as shown in Figure 6(b).
  • the DC/DC boost circuit is a non-isolated Boost, Buck or Buck/Boost boost circuit; or an isolated full-bridge, half-bridge, flyback, forward or push-pull conversion circuit.
  • the DC/AC inverter circuit inside the distributed power generation unit may be a single-stage H-bridge structure as shown in FIG. 7(a), FIG. 7(c) or FIG. 7(d), or may be in H.
  • the two-stage structure of the Boost converter is added in front of the bridge.
  • the Z-source H-bridge structure shown in Fig. 7(e) or the quasi-Z-source H-bridge structure shown in Fig. 7(f) can also be used.
  • the output of the inverter circuit is an AC low voltage.
  • the power switching device included in the distributed power generating unit may be a basic semiconductor device such as a triode, a MOSFT, or an IGBT, or a new power device such as SiC or GaN, and a thyristor SCR may also be used.
  • semi-controlled power devices such as GTO.
  • the control unit shown in Figure 8 is mainly composed of an output filter circuit, and a control, monitoring and communication module.
  • the total output voltage of the distributed power generating unit in series is connected to the control unit, and after passing through the filter composed of the inductors L1, L2 and C1, a pure sinusoidal alternating current is generated, integrated into the grid or output to the AC load.
  • the control unit has an integrated control and monitoring communication module, which generates the coordinated cluster control signals required by all power generation units, including all grid-related information collection, power detection, protocol conversion, grid side filtering, active derating, and reactive power compensation.
  • harmonic control and power grid fault traversing functions, and complete external communication, power generation status reporting and monitoring, control command uploading and dispatching, power grid dispatching, and security protection required for photovoltaic power generation systems, and implementing each distributed Cooperative cluster control, state acquisition, and calculation processing of power generation units.
  • the multiplexed cascade photovoltaic power generation system is composed of n structurally identical distributed power generation units and a unified control unit.
  • the power conversion part of the distributed generation unit is a single-stage H-bridge inverter circuit, and the digital control chip MCU realizes signal processing, MPPT tracking, control strategy and communication monitoring function.
  • the MCU of each power generating unit After receiving the coordinated cluster control signal from the control unit, the MCU of each power generating unit obtains the phase shift driving signal of the power switching device after real-time calculation and processing, so that the power generating unit realizes normal DC/AC inverter working.
  • the H-bridge inverter circuit can use the unipolar and bipolar modulation methods of the conventional technology.
  • the unipolar modulation can reduce the power consumption of the power switch tube and can generate the output of the three-level, unipolar-modulated H-bridge multiplex stage.
  • the working principle of the association is as follows:
  • the H-bridge can generate three levels in the unipolar modulation mode, that is, +Udc, 0, -Udc, where Udc is the photovoltaic DC input voltage.
  • Udc is the photovoltaic DC input voltage.
  • S11 and S14 are turned on, S12 and S13 are turned off, the output terminal level is +Udc; when S12 and S13 are turned on, S11 and S14 are turned off, the output terminal AC voltages AC11 and AC12 are at a level of -Udc;
  • S11 and S13 or S12 and S14
  • S12 and S14 or S11 and S13
  • the device is turned on at the same time, that is, the driving signals of the upper and lower switching devices of the same bridge arm (ie, S11 and S12 or S13 and S14) must be reversed.
  • Multiple power generation unit multiplex cascade control adopts triangular carrier phase shift modulation strategy, which is an SPWM method dedicated to cascading multi-level inverters, using a pair of modulated waves of the same amplitude and opposite phase with the same
  • the group carriers are compared to control the turn-on and turn-off of the left-right right-arm power tube of the respective unit.
  • the modulated waves are the same in different units, and the carriers are different by a certain angle.
  • the modulation drive signal of each distributed power generation unit is generated by comparing the triangular carrier and the sinusoidal modulation wave.
  • All the distributed power generation units adopt the same sinusoidal modulated wave signal, and the triangular carrier signals have the same frequency and amplitude modulation ratio to
  • the higher or lower switching frequency is SPWM modulated, but the phase of the triangular wave carrier of each distributed power generating unit is different, and the phase difference angle is ⁇ .
  • the corresponding output level number is (2n+1). If the H bridge uses bipolar modulation, then If the H-bridge uses unipolar modulation, then Therefore, the SPWM waves generated by each unit are staggered in phase with each other, and the carrier phase shift modulation strategy is mutually offset by the lower harmonics to increase the equivalent switching frequency.
  • the equivalent switching frequency of each unit is cascaded and cascaded to a single unit. 2n times the H-bridge. Therefore, this strategy can obtain higher waveform quality at a lower switching frequency, has good harmonic characteristics, effectively reduces switching loss, and can greatly reduce the volume of the total output filter inductor.
  • other modulation methods include harmonic elimination, switching frequency optimization, direct pulse width modulation, multi-level space voltage vector, etc. These methods are equally applicable to such multiple cascaded photovoltaic power generation systems.
  • a commonly used triangular wave carrier phase shift SPWM modulation circuit is shown in Fig. 12.
  • the carrier signal is generated by a triangular wave generator, and the modulated wave signal is generated by a sine wave generator.
  • the three carrier signals are respectively 60° out of phase, and are respectively compared with the same sinusoidal carrier signal to obtain the driving signal V1 of the upper arm of the left arm, and then inverted to obtain the driving signal V2 of the lower arm of the left arm, and the three carriers are used.
  • the drive signal V3 of the upper arm of the right bridge is obtained by comparing with the same sinusoidal carrier signal, and then the drive signal V4 of the lower arm of the right bridge is obtained after being inverted.
  • the waveform A of FIG. 13 is a triangular carrier signal
  • the waveform B is an inverted triangular carrier signal
  • the waveform C is a sine wave carrier signal
  • the waveform D is an H-bridge output voltage waveform.
  • Waveform A of Fig. 14 is an output multilevel voltage obtained by adding the output voltages of three power generating units, and waveform B is output filtered. Total output voltage output waveform after the road.
  • the multiplexed cascade photovoltaic power generation system includes a unified control unit.
  • the total output voltage of the distributed power generation unit output in series is connected to the control unit, and the sine wave is generated after the output filter circuit composed of the inductors L1 and L2 and the capacitor C1. Exchange, eventually merged into the AC grid or output to an AC load.
  • control unit integrates control, monitoring and communication modules to generate the coordinated cluster control signals required by all distributed power generation units, including all grid-related information collection, power detection, protocol conversion, grid side filtering, active derating, Reactive power compensation, harmonic control, and power grid fault traversing functions, and complete external communication, power generation status reporting and monitoring, control command uploading and dispatching, power grid dispatching, and security protection required for photovoltaic power generation systems, and Collaborative cluster control, state acquisition, and calculation processing of power generation units.
  • Each of the distributed power generation units and the distributed power generation unit and the control unit include a power connection and a signal connection to form a power flow and a signal flow.
  • the communication signals between each distributed generation unit and between the distributed generation unit and the control unit can be either a wired connection or a wireless connection, such as RS232, RS485, WIFI, Bluetooth, RF RF, or PLC power line. Different methods such as carrier communication.
  • the multiplexed cascade photovoltaic power generation system is composed of n structurally identical distributed power generation units and a unified control unit.
  • the power conversion part of the distributed power generation unit adds two-stage structure of the Boost converter to the front stage of the H-bridge, and the digital control chip MCU implements signal processing, MPPT tracking, control strategy and communication monitoring function.
  • the MCU of each distributed power generation unit After receiving the coordinated cluster control signal from the control unit, the MCU of each distributed power generation unit obtains the phase shift drive signal of the power switching device after real-time calculation and processing, so that the distributed power generation unit realizes the normal DC/AC inverter.
  • the triangular carrier phase shift modulation strategy is similar to the first embodiment shown in FIG. 9, and the description is not repeated here.
  • the multiplexed cascade photovoltaic power generation system is composed of n structurally identical distributed power generation units and a unified control unit.
  • the power conversion part of the distributed generation unit is a Z-source inverter circuit, and the digital control chip MCU realizes signal processing, MPPT tracking, control strategy and communication monitoring function.
  • the MCU of each distributed power generation unit After receiving the coordinated cluster control signal from the control unit, the MCU of each distributed power generation unit obtains the phase shift drive signal of the power switching device after real-time calculation and processing, so that the distributed power generation unit realizes the normal DC/AC inverter. jobs.
  • Z source inverter circuit has DC
  • the single-stage inverter topology of the boost function is a new type of inverter topology proposed in recent years. It mainly uses the same bridge arm power switch tube to realize the DC boost function when common, and the triangular carrier phase shift modulation strategy is shown in FIG.
  • the first embodiment is basically similar, only minor modifications are needed, and the description will not be repeated here.
  • the multiplexed cascade photovoltaic power generation system is composed of n structurally identical distributed power generation units and unified control units.
  • the power conversion part of the distributed power generation unit is a quasi-Z source inverter circuit, and the digital control chip MCU realizes signal processing, MPPT tracking, control strategy and communication monitoring function.
  • the MCU of each distributed power generation unit After receiving the coordinated cluster control signal from the control unit, the MCU of each distributed power generation unit obtains the phase shift drive signal of the power switching device after real-time calculation and processing, so that the distributed power generation unit realizes the normal DC/AC inverter. jobs.
  • the quasi-Z source inverter circuit is an improved structure of the Z-source inverter topology, and is also a single-stage inverter topology with DC boost function.
  • the multiplex cascade photovoltaic power generation system is composed of n structurally identical distributed power generation units and a unified control unit.
  • the power conversion part of the distributed power generation unit is an H-bridge inverter circuit, and the digital control chip MCU implements signal processing, MPPT tracking, control strategy, and communication monitoring functions.
  • the MCU of each distributed power generation unit After receiving the coordinated cluster control signal from the control unit, the MCU of each distributed power generation unit obtains the phase shift drive signal of the power switching device after real-time calculation and processing, so that the distributed power generation unit realizes the normal DC/AC inverter. jobs.
  • the topology operation principle of the distributed power generation unit and the triangular carrier phase shift modulation strategy are similar to the first embodiment shown in FIG. 9.
  • the main difference lies in the control unit, and the output filter circuit uses only the single inductor L1 to remove the inductor L2, and the other of the control unit. Part is identical to the first embodiment.
  • the inverter circuit inside the power generation unit can be a single-stage H-bridge, or a two-stage structure in which a Boost converter can be added in front of the H-bridge, and a different structure such as a Z-source or a quasi-Z-source inverter circuit can be used.
  • the multiplexed cascade photovoltaic power generation system is composed of n structurally identical distributed power generation units and a unified control unit.
  • the power conversion part of the distributed power generation unit is an H-bridge inverter circuit, and the digital control chip MCU implements signal processing, MPPT tracking, control strategy, and communication monitoring functions.
  • the MCU of each distributed power generation unit After receiving the coordinated cluster control signal from the control unit, the MCU of each distributed power generation unit obtains the phase shift drive signal of the power switching device after real-time calculation and processing. No., so that the distributed power generation unit can achieve normal DC/AC inverter operation.
  • the inductance L1 and L2 of the control unit output filter circuit are moved to the power generation unit to form a distributed filter structure, the topology operation principle of the distributed power generation unit and the triangular carrier phase shift modulation strategy and Similar to Figure 9, the rest of the control unit is identical.
  • the inverter circuit inside the power generation unit can be a single-stage H-bridge, or a two-stage structure in which a Boost converter can be added in front of the H-bridge, and a different structure such as a Z-source or a quasi-Z-source inverter circuit can be used.
  • the multiplex cascade photovoltaic power generation system is composed of n structurally identical distributed power generation units and a unified control unit.
  • the power conversion part of the distributed power generation unit is an H-bridge inverter circuit, and the digital control chip MCU implements signal processing, MPPT tracking, control strategy, and communication monitoring functions.
  • the MCU of each distributed power generation unit After receiving the coordinated cluster control signal from the control unit, the MCU of each distributed power generation unit obtains the phase shift drive signal of the power switching device after real-time calculation and processing, so that the distributed power generation unit realizes the normal DC/AC inverter. jobs.
  • the inductance L1, L2 and the capacitance C1 of the control unit output filter circuit are moved to the power generation unit to form a distributed filter structure, the topology operation principle of the distributed power generation unit and the triangular carrier phase shift.
  • the modulation strategy is similar to Figure 9, with the rest of the control unit being identical.
  • the inverter circuit inside the distributed power generation unit can be either a single-stage H-bridge or a two-stage structure in which the Boost converter is added in front of the H-bridge, and a different structure such as a Z-source or a quasi-Z-source inverter circuit can be used.
  • the multiplexed cascade photovoltaic power generation system is composed of n structurally identical distributed power generation units and unified control units.
  • the power conversion part of the distributed power generation unit is an H-bridge inverter circuit, and the digital control chip MCU implements signal processing, MPPT tracking, control strategy, and communication monitoring functions.
  • the MCU of each distributed power generation unit After receiving the coordinated cluster control signal from the control unit, the MCU of each distributed power generation unit obtains the phase shift drive signal of the power switching device after real-time calculation and processing, so that the distributed power generation unit realizes the normal DC/AC inverter. jobs.
  • the inductance L1 of the control unit output filter circuit is moved into the power generation unit to form a distributed filter structure, and the inductance L2 of the control unit output filter circuit is removed, and the topology operation of the distributed power generation unit is performed.
  • the principle and triangular carrier phase shift modulation strategy is similar to that of Figure 9, with the rest of the control unit being identical.
  • the inverter circuit inside the power generation unit can be a single-stage H-bridge, or a two-stage structure in which a Boost converter can be added in front of the H-bridge, and a different structure such as a Z-source or a quasi-Z-source inverter circuit can be used.
  • the multiplex cascade photovoltaic power generation system consists of three sets of n structures.
  • the identical power generation unit a, the power generation unit b, the power generation unit c, and the unified control unit constitute a multiplexed cascade photovoltaic power generation system having three phases without a neutral line N.
  • each set of n structurally identical distributed power generation units constitutes one power generation unit.
  • the power generation unit a includes a distributed power generation unit a1, a distributed power generation unit a2, ..., a distributed power generation unit an in series with an output phase;
  • the power generation unit b includes a distributed power generation unit b1, a distributed power generation unit b2, ...
  • the distributed power generation unit bn; the power generation unit c includes a distributed power generation unit c1, a distributed power generation unit c2, ..., a distributed power generation unit cn that are output in series.
  • the control unit includes a phase port, a b phase port, and a c phase port, wherein one end of each of the power generating units is electrically connected to the a phase port, the b phase port, and the c phase port of the control unit, respectively, and the other ends of the control unit are mutually connected Electrical connection.
  • the power conversion part of the distributed power generation unit inside the power generation unit is an H-bridge inverter circuit, and the digital control chip MCU implements signal processing, MPPT tracking, control strategy, and communication monitoring function.
  • the MCU of each distributed power generation unit After receiving the coordinated cluster control signal from the control unit, the MCU of each distributed power generation unit obtains the phase shift drive signal of the power switching device after real-time calculation and processing, so that the distributed power generation unit realizes the normal DC/AC inverter. jobs.
  • the inductance L1, L2, or capacitor C1 of the control unit output filter circuit can be moved to the power generation unit to form a distributed filter structure.
  • the topology working principle of the distributed power generation unit and the triangular carrier phase shift modulation strategy are similar to those of FIG. 9. The main difference is Using a three-phase phase-shifted 120-degree SPWM control strategy, the rest of the control unit is identical.
  • the inverter circuit inside the distributed power generation unit can be either a single-stage H-bridge or a two-stage structure in which the Boost converter is added in front of the H-bridge, and a different structure such as a Z-source or a quasi-Z-source inverter circuit can be used.
  • the multiplex cascade photovoltaic power generation system is composed of three sets of n identically identical power generation units a, power generation units b, power generation units c, and unified control units.
  • each set of n structurally identical distributed power generation units constitutes one power generation unit.
  • the power generation unit a includes a distributed power generation unit a1, a distributed power generation unit a2, ..., a distributed power generation unit an in series with an output phase;
  • the power generation unit b includes a distributed power generation unit b1, a distributed power generation unit b2, ...
  • the distributed power generation unit bn; the power generation unit c includes a distributed power generation unit c1, a distributed power generation unit c2, ..., a distributed power generation unit cn that are output in series.
  • the control unit includes a phase port, a b phase port, a c phase port, and a neutral port, wherein one end of each of the power generating units is electrically connected to the a phase port, the b phase port, and the c phase port of the control unit, respectively. The other ends of each are electrically connected to each other and to the neutral port Electrical connection.
  • the power conversion part of the distributed power generation unit inside the power generation unit is an H-bridge inverter circuit, and the digital control chip MCU implements signal processing, MPPT tracking, control strategy, and communication monitoring function.
  • the MCU of each distributed power generation unit After receiving the coordinated cluster control signal from the control unit, the MCU of each distributed power generation unit obtains the phase shift drive signal of the power switching device after real-time calculation and processing, so that the distributed power generation unit realizes the normal DC/AC inverter. jobs.
  • the inductance L1, L2, or capacitor C1 of the control unit output filter circuit can be moved to the power generation unit to form a distributed filter structure.
  • the topology working principle of the distributed power generation unit and the triangular carrier phase shift modulation strategy are similar to those of FIG. 9. The main difference is Using a three-phase phase-shifted 120-degree SPWM control strategy, the rest of the control unit is identical.
  • the inverter circuit inside the distributed power generation unit can be either a single-stage H-bridge or a two-stage structure in which the Boost converter is added in front of the H-bridge, and a different structure such as a Z-source or a quasi-Z-source inverter circuit can be used.
  • the embodiment of the present invention further provides a photovoltaic power generation device, which comprises any of the multiple cascaded photovoltaic power generation systems according to the first embodiment to the tenth embodiment of the present invention.
  • the photovoltaic power generation device can be a photovoltaic grid-connected power generation device, a photovoltaic off-grid power generation device, or a photovoltaic energy storage power generation device.
  • the multiplexed cascade photovoltaic power generation system connects at least one photovoltaic component through each of the distributed power generation units by providing a plurality of distributed power generation units connected in series with each other, since there is no need to directly connect the photovoltaic components in series, Component-level or distributed MPPT functions can be implemented to eliminate the barrel effect caused by the series connection of photovoltaic modules and increase the power generation of photovoltaic power generation systems.
  • the multiplexed cascade photovoltaic power generation system can reconstruct a photovoltaic power generation system structure, and each power generation unit can achieve higher working efficiency and use common AC cables, and at the same time remove conventional components such as a combiner box and a power optimizer, thereby reducing System price.

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  • Engineering & Computer Science (AREA)
  • Power Engineering (AREA)
  • Inverter Devices (AREA)
  • Supply And Distribution Of Alternating Current (AREA)

Abstract

L'invention porte sur un système multiplexé de production d'énergie photovoltaïque du type en cascade (100), et sur un appareil de production d'énergie photovoltaïque. Ledit système (100) comprend au moins un sous-système en cascade (110). Chaque sous-système en cascade (110) comprend une unité de commande (111) et au moins une unité de production d'énergie (113) raccordée électriquement à l'unité de commande (111). L'unité de production d'énergie (113) comprend une pluralité d'unités de production d'énergie distribuées (1131), les sorties étant raccordées en série. L'unité de commande (111) est raccordée électriquement à chaque unité de production d'énergie distribuée (1131). Chaque unité de production d'énergie distribuée (1131) est raccordée à au moins un ensemble photovoltaïque (1133), et s'utilise pour convertir une tension de courant continu de l'ensemble photovoltaïque (1133) en une tension de courant alternatif. Une tension de sortie totale est formée après raccordement en série des tensions de courant alternatif produites par la pluralité d'unités de production d'énergie distribuées (1131) et superposition de celles-ci. La tension de sortie totale est entrée dans l'unité de commande (111) et incorporée dans un réseau électrique au moyen de l'unité de commande (111), ou bien est transmise à une charge à courant alternatif. Ce système multiplexé de production d'énergie photovoltaïque de type en cascade (100) peut éliminer un effet d'auget dû au raccordement en série d'ensembles photovoltaïques (1133), et améliore la capacité de production d'énergie d'un système.
PCT/CN2016/080193 2016-04-26 2016-04-26 Système multiplexé de production d'énergie photovoltaïque du type en cascade, et appareil de production d'énergie photovoltaïque WO2017185223A1 (fr)

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PCT/CN2016/080193 WO2017185223A1 (fr) 2016-04-26 2016-04-26 Système multiplexé de production d'énergie photovoltaïque du type en cascade, et appareil de production d'énergie photovoltaïque

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Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN109088424A (zh) * 2018-09-27 2018-12-25 哈尔滨理工大学 一种级联式多功能离并网储能***及其控制方法
CN115224742A (zh) * 2022-09-21 2022-10-21 赫里欧绿能建筑科技有限公司 一种bipv光伏发电汇流并网***及方法
CN117478170A (zh) * 2023-12-26 2024-01-30 杭州禾迈电力电子股份有限公司 通信串扰抑制方法、管理模块、光伏设备及光伏***

Families Citing this family (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN107492911B (zh) * 2017-10-20 2021-04-13 阳光电源股份有限公司 一种级联逆变***
CN107947617A (zh) * 2017-10-23 2018-04-20 胡炎申 一种混合开关单相逆变器
CN107749720A (zh) * 2017-10-23 2018-03-02 胡炎申 一种混合开关三相逆变器
AU2020254497A1 (en) 2019-03-29 2021-10-21 Tae Technologies, Inc. Module-based energy systems having converter-source modules and methods related thereto
CN111490670B (zh) * 2020-06-16 2021-06-25 安徽大学 一种应用于大功率电源***的低次谐波抑制混合控制方法
CN114679079B (zh) * 2022-04-20 2024-03-26 合肥工业大学 基于梯形波调制的单相级联h桥光伏逆变器控制策略

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN101917016A (zh) * 2010-07-21 2010-12-15 北京交通大学 储能型级联多电平光伏并网发电控制***
CN104638676A (zh) * 2015-02-17 2015-05-20 河海大学 一种交流串联光伏发电并网***及其控制***和方法
CN105186574A (zh) * 2015-10-30 2015-12-23 阳光电源股份有限公司 一种逆变***及其控制装置和方法
CN105337519A (zh) * 2015-11-18 2016-02-17 阳光电源股份有限公司 级联多电平变换器的自检***及自检方法

Family Cites Families (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US9722427B2 (en) * 2012-06-25 2017-08-01 University Of Central Florida Research Foundation, Inc. Modular inverter system
WO2015070058A1 (fr) * 2013-11-07 2015-05-14 The University Of North Carolina At Charlotte Système de commande pour dispositif de production d'énergie électrique

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN101917016A (zh) * 2010-07-21 2010-12-15 北京交通大学 储能型级联多电平光伏并网发电控制***
CN104638676A (zh) * 2015-02-17 2015-05-20 河海大学 一种交流串联光伏发电并网***及其控制***和方法
CN105186574A (zh) * 2015-10-30 2015-12-23 阳光电源股份有限公司 一种逆变***及其控制装置和方法
CN105337519A (zh) * 2015-11-18 2016-02-17 阳光电源股份有限公司 级联多电平变换器的自检***及自检方法

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN109088424A (zh) * 2018-09-27 2018-12-25 哈尔滨理工大学 一种级联式多功能离并网储能***及其控制方法
CN115224742A (zh) * 2022-09-21 2022-10-21 赫里欧绿能建筑科技有限公司 一种bipv光伏发电汇流并网***及方法
CN115224742B (zh) * 2022-09-21 2022-12-20 赫里欧绿能建筑科技有限公司 一种bipv光伏发电汇流并网***及方法
CN117478170A (zh) * 2023-12-26 2024-01-30 杭州禾迈电力电子股份有限公司 通信串扰抑制方法、管理模块、光伏设备及光伏***

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