English Version Journal Login
EN
最新刊期
卷 50 ， 期 11 ， 2026
- 摘要：The high-efficiency transmission of power from 10-gigawatt-scale offshore wind power bases is crucial for supporting large-scale offshore wind power development. Novel collection and networking schemes are being actively explored both domestically and internationally. This paper presents a comparative analysis of the scenario applicability for three types of networking schemes: offshore DC hubs, offshore AC hubs, and onshore DC hubs. Focusing on the scenario of transmitting power from the ultra-large-scale Yangjiang offshore wind farm cluster directly to inland load centers, an offshore-onshore integrated networking and transmission scheme based on an onshore DC hub is investigated. The configuration scheme using modular multilevel converter (MMC) topologies, DC circuit breakers, and DC high-speed switches (HSS) in the DC networking is proposed. For the configuration scheme of “hybrid half-bridge/full-bridge MMC+HSS”, an excess power balance scheme that does not rely on centralized DC energy dissipation devices is introduced and applied in an actual engineering project. Three methods for the rapid activation of distributed energy dissipation in offshore wind turbines are proposed, followed by a comparative analysis of the characteristics and applicability of these methods. Combined with an engineering case study, the feasibility of the offshore-onshore integrated networking and transmission system and its DC fault clearing and ride-through methods is validated through digital simulation, which provides a new solution for the high-efficiency transmission of power from ultra-large-scale offshore wind farms in practical engineering applications.关键词：offshore wind power;offshore-onshore integrated networking;modular multilevel converter (MMC);high-speed switch (HSS);fault ride-through;distributed energy dissipation3|0|0更新时间：2026-08-21
- 摘要：To achieve cost-effective DC collection and transmission for large-scale renewable energy bases, this paper proposes an active-assisted commutation DC transformer (AAC-DCT) based on the thyristor. The AAC-DCT employs front-to-front connected 6-pulse thyristor bridges and diode bridges as the main conversion components, and incorporates a submodule chain (SMC) composed of a small number of fully controllable device submodules to assist in thyristor commutation. The AAC-DCT is designed to provide only DC voltage transformation and electrical isolation. Therefore, the SMC only needs a low-voltage output capability (approximately 15% of the rated DC voltage on the low-voltage side) to generate commutation voltage and drive the six thyristor bridge arms to conduct alternately. Based on the AAC-DCT, a partitioned multi-terminal DC collection scheme suitable for 10-gigawatt-level renewable energy bases is proposed. Power from multiple small-to-medium partitioned zones is transmitted to a collection station via lower-voltage DC collection lines, then boosted to ultra-high-voltage DC level by the AAC-DCT for centralized transmission. This scheme can solve the problems of reactive power compensation and voltage control encountered in AC collection schemes, and significantly reduce the investment cost of converters and lines in the DC collection system. Although the AAC-DCT lacks flexible control capability, the multi-terminal DC system formed by it can still achieve flexible power flow control through voltage regulation of the sending-end and receiving-end converters. Finally, the simulation verifies the feasibility of the AAC-DCT and the partitioned multi-terminal DC collection scheme.关键词：renewable energy base;thyristor;DC transformer;submodule chain (SMC);active-assisted commutation;multi-terminal DC collection;reactive power compensation;voltage control1|0|0更新时间：2026-08-21
- 摘要：To address the problems of limited transmission paths and insufficient flexibility in power regulation caused by the expansion of urban power grids, and in view of the application limitations of existing multi-terminal coordination control strategies in adapting to the special operational requirements of urban power grids, this paper proposes a virtual tie-line power coordination control strategy driven by power angles. This strategy establishes the mapping relationship between the power angle and the power of converter stations, simulates the power flow regulation mechanism of AC power grids, and automatically adjusts the active power in response to fast power angle fluctuations in partitioned power grids, thereby realizing adaptive power mutual assistance between regions. This strategy significantly reduces the reliance of the converter station on upper-level power commands, forming a hierarchical control architecture that takes medium-timescale upper-level optimized commands as the baseline and the short-timescale local adaptive regulation as a supplement. Finally, based on the PSCAD/EMTDC simulation platform, modeling and simulation are conducted for the modular multilevel converter based multi-terminal direct current (MMC-MTDC) system. The results show that the proposed control strategy can quickly respond to system operating condition changes within 100 ms. Compared with the local non-control scheme, the proposed control strategy can significantly reduce the power angle deviation of the converter station, and the power angle deviation between target areas is reduced by up to 75% in the scenario that a sudden load increase of 500 MW occurs in urban area Ⅰ, which verifies the effectiveness of the strategy.关键词：urban power grid;power coordination control;multi-terminal direct current (MTDC) transmission;modular multilevel converter (MMC);converter station;power angle control flexibility0|0|0更新时间：2026-08-21
- 摘要：Under the background of large-scale integration of renewable energy into power systems, the problems of power grid frequency and voltage stability have become increasingly prominent. The voltage source converter based high voltage direct current (VSC-HVDC) transmission system using conventional control lacks active support to the receiving-end grid. Therefore, a grid-forming control with active support capability for sending and receiving ends of VSC-HVDC transmission systems is proposed, in which the sending-end converter station adopts island control, and the receiving-end converter station adopts a hybrid synchronization control based on DC voltage regulation. The hybrid synchronization control flexibly combines grid-following control and grid-forming control, equivalently increasing the inertia and damping in the synchronous control loop, thereby enhancing the system transient stability. To maintain the voltage source characteristics of the converter during faults, a converter fault current limiting control method based on virtual impedance is proposed, and the impact of fault current limiting control on the system stability is studied. Finally, based on the proposed grid-forming control structure for VSC-HVDC transmission systems, a coordinated control strategy for sending and receiving ends of the system is proposed, achieving the participation of renewable energy dispatched from the sending end without communication in the frequency regulation of the receiving-end power grid. A simulation model of an offshore wind power two-terminal VSC-HVDC transmission system is built in PSCAD/EMTDC, validating the effectiveness of the proposed grid-forming control for sending and receiving ends of VSC-HVDC transmission systems.关键词：voltage source converter based high voltage direct current (VSC-HVDC) transmission system;renewable energy;grid-forming control;hybrid synchronization control;transient stability;fault ride-through;fault current limiting control;virtual impedance1|1|0更新时间：2026-08-21
- 摘要：The hybrid DC transmission system with a series topology of diode rectifier unit (DRU) and modular multilevel converter (MMC) has great economic advantages and has good application prospects in the transmission system of renewable energy bases. First, this paper introduces a hybrid DC topology suitable for offshore wind power transmission systems and control strategies for the sending and receiving ends. In order to solve the power imbalance problem of offshore wind power, DRU and MMC during steady-state operation, two submodule average voltage control strategies are proposed. Then, a collaborative start-stop process between the sending- and receiving-end converters and the offshore wind power system is proposed. The influence of offshore wind power and switching time of DRU AC/DC switch state on the capacitor voltage rise of the sending-end module is analyzed during the start-stop process. Finally, a PSCAD/EMTDC simulation model of diode hybrid DC is constructed to verify the effectiveness of the proposed steady-state operation and start-stop strategy.关键词：offshore wind power;diode rectifier unit;DC transmission system;steady-state operation;start-stop1|3|0更新时间：2026-08-21
- 摘要：With the rapid development of voltage source converter based high voltage direct current (VSC-HVDC) transmission technology, receiving-end power grids will gradually present a hybrid multi-infeed scenario incorporating both VSC-HVDC and conventional HVDC transmission. This paper studies the interactive oscillation characteristics between the modular multilevel converter (MMC) and the line commutated converter (LCC) in a hybrid multi-infeed receiving-end system based on the whole-system impedance method. Firstly, based on the harmonic state-space method, the wide-frequency impedance models of the MMC and LCC considering harmonic coupling characteristics are established, respectively, and a whole system impedance model of the receiving-end system is further constructed. Secondly, based on the whole system impedance analysis method, the potential oscillation risks, dominant oscillation nodes, and key influencing factors of the hybrid multi-infeed receiving-end system are studied, and then the source-load partitioning scheme is determined to analyze the interactive oscillation characteristics between MMC and LCC. Finally, the correctness of the theoretical analysis is verified by establishing a time-domain simulation model of an LCC-MMC hybrid dual-infeed receiving-end system.关键词：hybrid multi-infeed receiving-end system;voltage source converter based high voltage direct current (VSC-HVDC) transmission;oscillation;impedance model;modular multilevel converter (MMC);line commutated converter (LCC)0|1|0更新时间：2026-08-21
- 摘要：To address the issues related to voltage stability deterioration and inadequate inertia support resulting from high penetration of renewable energy into the power grid, this paper proposes a control strategy for the static synchronous compensator (STATCOM) using the topology of the modular multilevel converter (MMC) with energy-storage submodules. This strategy has the active support capability. First, a fault detection mechanism based on DC voltage and system frequency is proposed to facilitate adaptive switching between steady-state and transient operation modes. Then, during fault period, the MMC-STATCOM with energy-storage submodules is regulated to release energy from the energy storage unit to compensate for a power shortage within the system. In response to load disturbances, a frequency droop coefficient is used to regulate the charging and discharging power of the energy storage unit, thereby mitigating frequency fluctuations. Finally, the proposed coordinated control strategy is verified through PSCAD/EMTDC and RTDS simulations. The simulation results show that the MMC-STATCOM with energy-storage submodules can promptly respond to frequency variations during various transient processes, while simultaneously providing reactive power support, smoothing power fluctuation within the system, and significantly enhancing the comprehensive stability of the high-voltage DC transmission receiving-end system.关键词：DC receiving-end system;transient stability;static synchronous compensator (STATCOM);submodule;energy storage;modular multilevel converter (MMC);voltage support;frequency support1|2|0更新时间：2026-08-21
- 摘要：In conventional high voltage direct current (HVDC) transmission, line commutated converters (LCCs) are employed at the receiving end. During AC voltage dips, the extinction angle margin decreases, which can easily trigger commutation failures. The switchable current source converter effectively avoids commutation failure risks by virtue of its active switchable capability. However, in transient conditions, after the fully controlled devices of the switchable current source converter are switched off, the surge arrester needs to be conducted to assist the commutation process. Nevertheless, the conduction of the surge arrester introduces additional forced commutation stages, which affects the harmonic characteristics of the system. In view of the current insufficiency in theoretical analytical research on this type of converter, this paper conducts an analytical analysis on the harmonic characteristics of the switchable current source converter and an assessment study on the filter stress. Firstly, the differences in the switching sequence of the controllable line commutated converter (CLCC) under steady-state and transient conditions and their impacts on the commutation characteristics are analyzed. Secondly, the analytical expressions of the voltage and current at each stage of the converter considering the influence of the forced commutation angle are derived. Thirdly, based on the fast Fourier transform (FFT) theory, the harmonic components on both AC and DC sides are accurately analyzed. Finally, a simulation model is built in PSCAD/EMTDC to verify the correctness and effectiveness of the proposed harmonic analysis method, and the current stress of the filter under various working modes is verified through simulation.关键词：current source converter;line commutated converter (LCC);surge arrester;harmonic;commutation;transient condition;current stress0|0|0更新时间：2026-08-21
- 摘要：The grid-forming flexible DC converter stations based on the single closed-loop voltage control exhibit excellent voltage support capability for the AC power grid. However, it faces a high risk of oscillation in the low-frequency power range (0~100 Hz), especially in the near-fundamental frequency band (46~54 Hz). Firstly, a detailed theoretical analysis model of the flexible DC converter station is established, the open-loop transfer function of the power angle at the point of common coupling is derived, the generation mechanisms of power oscillations in the near-fundamental frequency and low-frequency ranges are revealed, and corresponding suppression principles are proposed. Secondly, targeting the two types of oscillation risks, a low-frequency damping control strategy is proposed, and the influence of this strategy on the power angle open-loop transfer function and low-frequency impedance is analyzed. The results show that the impedance provided by the damping controller can be separated from the original impedance of the modular multilevel converter into an additive analytical expression. On this basis, a parameter design method for compensating the integral area of negative damping in the low-frequency range is proposed, and the analytical selection range of parameters is given. Finally, the correctness of the proposed model and damping control strategy is verified through both theoretical analysis and electromagnetic transient simulations.关键词：flexible DC transmission;converter station;grid-forming control;single closed-loop voltage control;near-fundamental frequency oscillation;damping control;parameter design0|0|0更新时间：2026-08-21
- 摘要：The commutation voltage and the critical extinction angle jointly act on the minimum extinction area of the converter, thereby influencing the commutation failure of high voltage DC system. Existing research usually ignores the dynamic changes of the minimum extinction area during the fault period, which leads to misjudgment of commutation failure under certain operation conditions and simultaneously affects the suppression effect. To solve the above problems, first, considering the dynamic characteristics of the commutation voltage and the critical extinction angle under AC faults, the minimum extinction area of the converter during the fault period is predicted. And the extinction safety margin coefficient of the converter is proposed and the commutation failure is predicted based on this coefficient. Then, the difference of the extinction area between the fault and the steady state is calculated. The quantitative relationship between the compensation amount of the extinction area and the extinction angle is established. Based on the predicted result of the extinction safety margin coefficient, the commutation failure is suppressed by compensating the extinction area during the fault period. By combining the extinction safety margin coefficient and the dynamic characteristics of DC current during the fault recovery period, the DC current command is optimized by adjusting the extinction area during the recovery period, achieving the suppression of subsequent commutation failure while accelerating the DC recovery speed. Finally, a DC simulation model is built on PSCAD/EMTDC to verify the effectiveness of the proposed prediction method and suppression strategy for commutation failure, as well as the superiority over existing methods.关键词：high voltage direct current (HVDC) transmission;commutation failure;extinction area;safety margin;prediction method;suppression strategy0|1|0更新时间：2026-08-21
- 摘要：The integration of large-scale renewable energy and multi-infeed high voltage direct current (HVDC) have made the coupling characteristics of AC and DC faults in the receiving-end power grid more complex, and it urgently needs typical cases that can support in-depth studies on the stability mechanisms and operating characteristics of multi-infeed HVDC systems. Therefore, based on the general study methods for commutation failures and stability characteristics of multi-infeed HVDC receiving-end power grid, six key indicators for designing typical cases are proposed. Meanwhile, combined with the actual topology and control parameters of the receiving-end power grid, a typical case of the multi-infeed HVDC system with large-scale renewable energy integration is constructed. Through full electromagnetic transient modeling and simulation, it shows that the proposed typical case can fully reflect the scale and strength, multi HVDC commutation failure characteristics, and complex AC/DC power grid stability characteristics of actual multi-infeed HVDC receiving-end power grids,meeting the actual application requirements.关键词：multi-infeed HVDC system;typical case;renewable energy;commutation failure;stability;simulation;modeling1|1|0更新时间：2026-08-21
- 摘要：In recent years, various controllable turn-off converter topologies based on fully controlled devices are successively proposed to address the commutation failure problem in high voltage direct current transmission systems and have made significant progress. However, there are generally problems of high cost and low reliability due to the large number or capacity of fully controlled devices. Therefore, a novel controllable turn-off hybrid line commutated converter (HLCC) topology is proposed. This topology constructs a centralized turn-off interphase circuit combining fully-controlled and semi-controlled devices. Transfer circuits composed of semi-controlled devices connect each bridge arm, and the three-phase three bridge arms share a common turn-off circuit composed of fully-controlled devices, enhancing the utilization rate of the fully-controlled valves and their parallel surge arresters of the turn-off circuit. Compared to existing controllable line commutated converters, the number of fully-controlled devices required for forced commutation in the turn-off circuit is reduced by two-thirds. To verify this topology, a digital simulation (PSCAD/EMTDC) and physical dynamic model experimental system are established. Experimental results demonstrate that the proposed topology achieves stable operation without commutation failure under typical fault conditions such as single-phase grounding, interphase and three-phase short circuits in AC systems.关键词：high voltage direct current transmission system;commutation failure;controllable turn-off;line commutated converter (LCC);topology;turn-off circuit;physical dynamic model experimental system0|0|0更新时间：2026-08-21
- 摘要：To address the issues of low power density in traditional modular multilevel converters (MMCs) and the need for large DC-link capacitors in existing alternate arm converters (AACs), this paper proposes a three-phase asymmetrical multiplexing-arm converter (TAMC) topology with a high power density and its corresponding control method. In the TAMC, two phases adopt multiplexed alternate arm structures, which achieves high module utilization and high power density while eliminating the arm inductors. The third phase retains the upper and lower arm structures of the conventional MMC to stabilize the DC voltage, thereby removing the requirement for a DC-link capacitor. This paper provides a detailed analysis of the operating mechanisms of the TAMC, proposes key parameter design guidelines, and develops a closed-loop control strategy that includes AC/DC current control and arm energy balancing control, ensuring stable operation under multiple working conditions, including a wide range of power factors and power grid voltage sags. Simulation and hardware-in-the-loop experimental results demonstrate that the proposed topology significantly reduces the number of submodules and energy storage of capacitors, eliminates arm inductors, and maintains excellent operational performance. The feasibility of the proposed topology and the effectiveness of the control strategy are verified.关键词：flexible DC transmission;modular multilevel converter (MMC);power density;low cost;arm;energy balancing;fault ride-through0|0|0更新时间：2026-08-21
- 摘要：Power transmission through DC networking is a feasible transmission solution for renewable energy bases. However, the existing submodule hybrid modular multilevel converter (MMC) requires all converter stations to operate when facing a single line fault, which cannot meet the requirement for selectivity. To achieve a low-cost and selective DC fault clearance, this paper proposes a dual-port converter valve hybrid modular multilevel converter (DCH-MMC). The core idea of the proposed DCH-MMC is to embed a full-bridge structure shell outside the half-bridge valve section to achieve the flipping of DC port voltage of MMC, thereby applying a negative voltage to the faulty line for the selective fault clearance. The DC fault clearance principle, electric stress, and parameter design of the new topology are analyzed and verified in the DC power grid environment. The results show that the proposed DCH-MMC scheme can selectively clear the fault within 13.4 ms after its occurrence. Compared with existing engineering schemes, the proposed scheme can reduce investment costs by approximately 25% to 40%.关键词：flexible DC transmission;multi-port converter valve;modular multilevel converter (MMC);fault clearance;full-bridge submodule0|0|0更新时间：2026-08-21
- 摘要：The modular multilevel converter based ultra-high voltage direct current (MMC-UHVDC) transmission projects typically adopt hybrid MMCs with DC fault clearance capability, and require the proportion of full-bridge submodules (FBSMs) to exceed 50%, which results in high investment costs and operational losses of the project. Aiming at the scenario of large-scale renewable energy transmission via long-distance overhead lines in China’s inland areas, this paper proposes a low-cost MMC-UHVDC transmission system with heterogeneous high- and low-voltage valves. The system can achieve DC fault ride-through without blocking by configuring only 37.5% FBSMs. First, the topological structure and operational characteristics of the system are introduced, and the steady-state control strategy is proposed. Then, the transient operational characteristics of the system are analyzed, and the AC/DC fault ride-through strategies are presented. On this basis, the economy of the proposed transmission scheme and the conventional MMC-UHVDC transmission scheme is compared and analyzed. Finally, a model of the MMC-UHVDC transmission system with heterogeneous high- and low-voltage valves is built on the PSCAD/EMTDC simulation platform, and the effectiveness of the proposed topology and control strategies is verified through simulation.关键词：ultra-high voltage direct current (UHVDC) transmission;valve;modular multilevel converter (MMC);fault ride-through;renewable energy integration;overhead line;full-bridge submodule (FBSM)0|0|0更新时间：2026-08-21
- 摘要：The ultra-high voltage (UHV) large-capacity direct current (DC) transformer is key equipment for realizing DC collection and transmission of large-scale renewable energy bases in desert Gobi and other arid areas. This paper proposes a multi-port UHV large-capacity DC transformer based on the principle of capacitive partial energy transfer. Each arm of the DC transformer is connected between the collection side and the transmission side, only requiring bearing the voltage difference between the collection and transmission ports, and can directly transfer the DC power from the collection side to the transmission side. Meanwhile, the arm alternately connects in parallel on the collection side and in series between the collection side and the transmission side to realize current switching, and the inner sub-module capacitors of the arm achieve efficient capacitive energy balance by absorbing and releasing power. In addition, the DC transformer adopts thyristor and diode valve groups, and can reduce equipment costs and improve operational efficiency. The DC transformer has a multi-port structure, and can isolate faults at the collection port without affecting the normal operation of other collection ports. This paper introduces the details of topological structure, operating principle, parameter design method, control strategy, fault blocking and post-fault switching operation strategy of the proposed DC transformer. The effectiveness of the proposed DC transformer and its operating principle design is verified through simulation cases, and quantitative comparison results with modular multilevel converters in terms of the number of power devices, energy storage, and power losses are presented.关键词：desert Gobi and other arid areas;direct current (DC) transformer;ultra-high voltage direct current (UHVDC) transmission;direct current (DC) collection;multi-port;capacitive energy transfer;direct current (DC) fault0|0|0更新时间：2026-08-21
- 摘要：To improve the capability of high voltage direct current (HVDC) transmission systems against commutation failure, the engineering design of a hybrid commutated converter (HCC) valve is completed based on the novel HCC topology of the reverse blocking integrated gate commutated thyristor (IGCT), and its engineering application is realized in the Lingbao upgrade project of China. Systematic research is carried out focusing on the selection of key components, electrical design principles and insulation coordination strategies of the HCC valve. A series of engineering adaptability studies are also conducted, including electric field distribution simulation, valve loss evaluation, control system compatibility analysis, as well as insulation and operation test verification. The engineering prototype of the HCC valve has passed performance verification through insulation and operation tests, and successfully achieved six consecutive active turn-offs of the converter valve under a high current of 5 500 A. The results demonstrate that the HCC valve prototype can realize fast and reliable fault current turn-off, verifying its engineering feasibility.关键词：high voltage direct current (HVDC) transmission system;commutation failure;hybrid commutated converter (HCC);reverse blocking integrated gate commutated thyristor (IGCT);fault current turn-off;insulation coordination0|0|0更新时间：2026-08-21
Technology for HVDC Form Construction and Equipment in New Power Systems
- 摘要：With the advancement of new power system construction, China has witnessed rapid growth in installed energy storage capacity. Although market reforms are advancing steadily, not all energy storage projects are operated through market-based mechanisms. Their investment cost recovery mechanisms are diversified, with some still following non-market approaches. In existing studies on energy storage dispatch, operation costs are typically incorporated into optimal decision modeling. However, in-depth analysis of investment cost recovery mechanisms and their sensitivity to policies still requires further strengthening. To this end, this paper takes Chongqing power grid, a typical receiving-end power grid of China, as the research object. Considering its future development trends, an investment cost recovery model for multi-type energy storage is constructed to analyze key influencing factors on investment cost recovery for multi-type energy storage and calculate their investment cost recovery periods. Addressing the practical demands of investment cost recovery for energy storage, and taking into account power grid operation requirements, energy storage investment cost recovery demands, and government price stability constraints, the energy storage dispatch strategy for the receiving-end power grid is optimized based on current energy storage dispatch mechanisms. This provides a quantitative analysis basis for policy design and the improvement of energy storage dispatch mechanisms.关键词：receiving-end power grid;energy storage;investment cost recovery;optimal decision;dispatch0|2|0更新时间：2026-08-21
- 摘要：To reduce the wind curtailment loss in large-scale offshore wind power clusters and enhance the efficiency of multi-energy coordinated dispatching in coastal areas, a two-stage optimal dispatching method for coastal energy systems integrating offshore wind power based hydrogen production is proposed. Firstly, considering the coupled power output characteristics of upstream and downstream wind farms and the power-following effect driven by incoming wind directions in the wind-hydrogen system, a dynamic energy transfer model for multiple wind farm clusters with variable wind direction angles is proposed. Secondly, in response to faults in the offshore wind power collection lines, an autonomous operation strategy for the wind-hydrogen system that adapts to such faults is proposed. Additionally, a sea-land coupled hydrogen energy supply chain network is constructed based on hydrogen transport vessels. Furthermore, by taking into account the impact of wind power forecast deviations, load demand fluctuations, and uncertainties associated with collection line faults, a two-stage robust optimization method for coastal energy systems integrating offshore wind power based hydrogen production is proposed, and it is solved by using a nested column-and-constraint generation algorithm. Finally, the verification results from numerical cases demonstrate that the system operation cost decreases by 9.03% under the influence of uncertainties, verifying the effectiveness and superiority of the proposed method.关键词：offshore wind power;hydrogen production;wind power cluster;dynamic energy transfer;coastal energy system0|0|0更新时间：2026-08-21
- 摘要：In view of the fact that the existing electrolyzer models mostly describe their operational characteristics at the hour-level or minute-level timescales, and fail to fully explore their second-level response characteristics, leading to low operation efficiency and insufficient capacity for renewable energy accommodation, an optimal power allocation strategy for alkaline (ALK) electrolyzer and proton exchange membrane (PEM) electrolyzer combined hydrogen production system considering the second-level response characteristics of the electrolyzers is proposed. Firstly, the operation mechanisms of ALK and PEM electrolyzers are analyzed, and their power-efficiency curves are drawn. Secondly, based on the highest efficiency point, rated power point and overload power point on the curves, and considering the operation costs, single-cell capacity, response performance of the two types of electrolyzers, as well as the second-level start-stop and second-level regulating characteristics of PEM electrolyzers, an optimal power allocation strategy for the ALK-PEM hybrid electrolytic hydrogen production system is formulated. On this basis, combined with the dual-layer array rotation operation rules of multi-electrolyzer, the reasonable power distribution of the array between groups in the hybrid electrolytic hydrogen production system is achieved. Finally, by taking the actual data of a demonstration project in Heilongjiang Province of China as an example, it is verified that the proposed optimal power allocation strategy for ALK-PEM electrolyzers can promote renewable energy accommodation while increasing the hydrogen production revenue.关键词：electrolytic hydrogen production;electrolyzer;proton exchange membrane (PEM);second-level characteristics;optimal power distribution;array rotation0|0|0更新时间：2026-08-21
- 摘要：When a photovoltaic-energy storage DC microgrid system faces dynamic disturbances such as photovoltaic power fluctuations and rapid load switching, the bus voltage is prone to uncertain fluctuations. The voltage regulation control strategy relying on fixed parameter tuning cannot respond to system state changes in real time or adapt to complex operating conditions. This paper designs an active disturbance rejection voltage control strategy for a bidirectional DC-DC converter that integrates the reinforcement learning state-action-reward-state-action (SARSA) algorithm. A linear extended state observer is used to estimate and compensate for the total system disturbance. Meanwhile, an artificial intelligence algorithm is introduced to optimize and adjust the controller parameters, achieving real-time adaptive adjustment of the observer parameters. Finally, in various disturbance scenarios, the proposed SARSA-based linear active disturbance rejection control (LADRC) strategy is compared with other strategies on both digital simulation and physical experimental platforms. Simulation and experimental results show that the SARSA-LADRC strategy achieves better bus voltage control.关键词：DC microgrid;voltage control;converter;state-action-reward-state-action (SARSA) algorithm;linear active disturbance rejection control (LADRC);artificial intelligence0|0|0更新时间：2026-08-21
- 摘要：The load structure of distribution transformer areas is complex, and the data volume is enormous. Among them, the temperature-controlled transformer area load is more significantly affected by extreme temperatures, which further intensifies the volatility and randomness of the transformer area loads. To improve the efficiency and accuracy of short-term forecasting for massive transformer area loads under high- and low-temperature meteorological conditions, this paper proposes a short-term load forecasting model for transformer areas based on cumulative effect temperature-feature correction and incremental learning. Firstly, on the intraday time scale, considering the differences in fluctuation patterns between load and temperature features, a dynamic cumulative effect temperature-feature correction model is constructed. Secondly, by using XGBoost and hierarchical clustering techniques, a two-layer refined classification of large-scale mixed transformer areas is achieved. The proposed correction model is then applied to correct the temperature features of temperature-sensitive transformer areas, thereby constructing a high-correlation feature dataset for multiple types of transformer areas. Subsequently, by combining the iTransformer neural network with incremental learning methods, an efficient and high-generalization online incremental load forecasting model is established. Finally, simulation verification is performed by taking the load data of 6 251 transformer areas in Shanghai of China as an example. The verification results show that the proposed transformer area load forecasting model has faster training speed and higher forecasting accuracy.关键词：distribution network;load forecasting;transformer area;extreme weather;cumulative effect;incremental learning0|2|0更新时间：2026-08-21
Basic Research
- Technical support is provided by Beijing Founder electronics co., LTD 京ICP备09064830号-19
京公网安备11010802024621 - It is recommended to read the content of this site in Chrome&IE9+. Please switch to extreme mode in browser 360.
- Cookies We use cookies to help provide and enhance our service and tailor content. By continuing, you agree to the use of cookies.
0