Development Of SSP510 Frequency Voltage Emergency Control Device

In recent years, China's rapid economic growth promote the development of the industry. The power system put forward higher requirements; the construction of smart grid has become an inevitable trend of development. China's power grid automation and information level is relatively low, because of the low performance and poor reliability of the power distribution network communication system. But in the smart grid, electric business increased put forward higher requirements for the communication terminal. The development of smart grid construction plays an important role in the communication network of electric power system, this paper will focus on the necessity of the construction of smart grid, analysis of electric power communication and its role in the smart grid, and the power communication terminal access architectures are described, in order to ensure the orderly and efficient operation of the smart grid.

Based on an analysis of the misunderstanding and problems concerning wind power development, this paper summarizes the experiences of coordinated development of wind power and power grids in typical countries, proposes the principles and strategies for the coordinated development of wind power and power grids in China. Technically, bidirectional friendly technologies should be deployed to ensure the security of power system. In regulatory term, a complete and standardized regulatory strategy is key to harmonious interaction among different stakeholders concerning wind development. Incentive policies should be comprehensive, foreseeable and sustainable. Related measures and suggestions for large scale development of wind power in China are put forward.

With the UHV (Ultra High Voltage) power grid construction and the interconnection of regional power grids, the scale of power grids in China is increasing rapidly. At the same time, significant uncertainty and variability is being introduced into power grid operation with the integration of large-scale renewable energy in power systems. All of these pose an enormous challenge to the operation control of power systems in China. For a long time, online static security analysis, as an important part of EMS (Energy Management System), has been an effective tool for power grid operation. However, it is increasingly difficult for traditional static security analysis in serial computing mode to be online applied in bulk power grids in China. A new practical parallel approach for online static security analysis is put forward in this paper. A multithread parallelism is introduced into contingency screening, detailed contingency evaluation and decision support for reducing the execution time. By employing the multithread technology, the hardware resources of multi-processor/multi-core computer can be fully used and the program can be speeded up effectively. The performance of the parallel static security analysis is demonstrated by tests on two large-scale power systems. The test results show that the proposed method can be online applied in real bulk power grids.

This study presents the analysis of debates on the future super grid in China. The rapid increase of power demands and the uneven distribution of energy bases and load demands in China require bulk‐capacity long‐distance power transmission. Two candidate solutions are thus proposed, that is, the ultra‐high‐voltage ac (UHVAC) synchronous power grid and the extra high‐voltage ac (EHVAC) asynchronous super power grid. The debates on the above two power grids are first reviewed. The two candidate power grids are then compared in detail in terms of security, economic and environmental aspects. Finally, this study provides a suggestion for the construction of UHV synchronous power grid in China as well as the future research direction. The research, discussion and conclusion related to UHVAC and EHVAC transmissions in China are expected to provide useful references for power system planning in other countries and to promote the development of the global power industry.

The successful application of smart substations in China's power grid makes the operation of the power grid system more intelligent and visualized. However, the high degree of information integration of smart substations, complex equipment principles, and incomplete related technical means have caused a certain degree of difficulty in on-site operation and maintenance. Based on the analysis of a 220kV smart substation main transformer protection maloperation accident, it is concluded two main factors that affect the malfunction of protection. On the one hand, professionals lack understanding of the principles and treatment methods of the equipment, and it is difficult to find some hidden faults on site. On the other hand, in the process of equipment maintenance, the method and degree of safety measures are difficult to be accurately mastered, and it is easy to cause hidden faults. All of the above have caused hidden dangers to the safe and stable operation of the power grid. This requires operators and maintenance personnel to have an in-depth understanding of smart substation technology, improve the reliability of relay protection operations, and accurately isolate grid faults.

Smart grid planning and construction is a very complex engineering project that requires intelligent technology to protect systems such as grid lines and substations to control grid stability and power quality. The smart grid GIS resource allocation technology has designed a new system architecture for the needs of building smart grids. The article expounds the key technologies and typical applications of smart grid GIS resource allocation technology, and describes its broad application prospects in smart grid. As a public service platform for graphical display applications, GIS platform constructs a spatial geographic information data center, which is intelligent. Applications such as grid integration, data mining, and intensive resource utilization provide a massive data storage, management, and analysis environment. The grid GIS platform provides geospatial information sharing and business application integration for smart grid power generation, transmission, substation, power distribution, power consumption, dispatching, etc., providing planning methods and visual analysis services for the construction of smart grid systems.

Studying the propagation of cascading failures through the transmission network is key to asses and mitigate the risk faced the energy system. As complex systems the power grid failure is often studied using some probability distributions. We apply 4 well-known probabilistic models, Poisson model, Power Law model, Generalized Poisson Branching process model and Borel-Tanner Branching process model, to a 14-year utility historical outage data from a regional power grid in China, computing probabilities of cascading line outages. For this data, the empirical distribution of the total number of line outages is well approximated by the initial line outages propagating according to a Borel-Tanner branching process. Also for this data, Power law model overestimates, while Generalized Possion branching process and Possion model underestimate, the probability of larger outages. Especially, the probability distribution generated by the Poisson model deviates heavily from the observed data, underestimating the probability of large events (total no. of outages over 5) by roughly a factor of 10-2 to 10-5. The observation is confirmed by a statistical test of model fitness. The results of this work indicate that further testing of Borel-Tanner branching process models of cascading failure is appropriate, and should be further discussed as it outperforms other more traditional models.

Wind damage is one of the common disaster that has serious influence on China’s power grid. The wind damage has a wide distribution and a low success rate of reclose, which makes the transmission line outage more likely. In this study, it is found that the 2016 wind damage of power grid in China’s major areas mainly distributed in the southeastern coast, southwest region, north China and its surrounding areas. In temporal distributions, wind damage mainly occurs in summer and afternoon. In 2016, the first reclose success rate of wind damage trip is only about 10% during 330 kV and above voltage level transmission lines. 220 kV is a voltage level threshold of trip line: tripps number increases with voltage level decreases when above the threshold, otherwise trips number decreases with voltage level decreases. Transmission line wind damage trip trend has a large interannual variation from 2010 to 2016. This study analyzes the characteristics of wind damage trips in 2016, which provides guidance for wind damage prevention work in windbreak-prone areas and windbreak-prone periods.

Synthetically analyze the power distribution communication network technology in the smart power grid link. It mainly includes the summary of the smart distribution network, electric power communication backbone network and then layer communication requirements, the network mode and the application mode of WLAN technology in the distribution network, EPON network technology, micropower wireless technology, PTN technology and power broadband wireless systems. State the demand of the smart power distribution business and put forward technical guidance for the smart power distribution communication network scheme. In view of the complex distribution network architecture, more nodes and scattered, complex business types data business needs, put forward the integrated solutions of optical fiber communication as the backbone access, wireless bandwidth, passive optical communication as the coverage, the short distance wireless communication as the main terminal access. It provides a reference for the communication plan of distribution side.

Feasibility and performance analysis of a novel air separation unit with energy storage and air recovery

Power sector is the largest industrial emitter in China, and renewable energy development would contribute to the large-scale construction of power grid. Mitigating carbon emissions of power gird construction is extremely important. So, the objective of this study is to understand embodied carbon emissions of power grid construction under carbon neutrality target, and then put forward to policy implications of carbon mitigation. This study, based on top-down and bottom-up integrated assessment models (IAMs), investigates carbon emissions of power grid construction towards 2060, through identifying the key driving factors and forecasting their embodied emissions in line with China's carbon neutrality target. Our results show that, the increase of Gross Domestic Product (GDP) dominates the increase in embodied carbon emissions of power grid construction, while energy efficiency and energy structure improvement contribute to the decrease. Large scale renewable energy development promotes the power grid construction. In 2060, total embodied carbon emissions would increase to 1105.7 Million tons (Mt) under the carbon neutrality target. However, the cost and key carbon-neutral technologies should be re-considered to ensure the sustainable electricity supply. The results could provide data reference and decision-making of designing power construction and mitigating carbon emissions of power sector in future.

In the context of modern big data, power grid information technology is a particularly important work for power grid staff. In the process of the in-depth construction of smart power grid, the demand for the integration of monitoring data of marketing operation is also increasing, and the data exchange is developing towards the direction of complexity, which requires the continuous improvement of the real-time performance of data and the risks in performance, security and management risks generated by data integration should be reduced. It is particularly important to create a unified management tool for data interaction. Through the professional R&D team in big data technology, the marketing operation monitoring data sharing can be highlighted, to create an integrated marketing data center. At present, the construction of marketing operation monitoring information is the focus of the work, which can effectively promote the development of big data. Therefore, this paper analyzes the data architecture of the marketing operation monitoring platform under the smart grid for the reference of relevant research.

In power system operation, there are usually a few vulnerable lines (VLs) which are prone to exacerbate the propagation of cascading failures and lead to severe blackouts with high probability. To facilitate preventing the power grid from cascading blackouts, in this paper, a PageRank-based fast screening method is derived to identify VLs. To this end, we extend the concept of interaction graph to model cascading outages as a directed weighted graph, where impacts of hidden failures are first taken into account. Based on the graph, we modify the celebrated PageRank algorithm to derive an ultra-fast VLs screening algorithm for large-scale power grids. Simulations carried out on the IEEE 118-bus system show that the proposed method can achieve high-accuracy VLs screening while the speed can be enhanced for several orders of magnitude compared with cascading failure simulation methods. Tests on a 1122-bus real power grid in China demonstrate that it can discriminate the most VLs in a practical power grid within only several minutes, showing its great potential for on-line application.

Performance and reliability of electrical power grids under cascading failures

Chinese energy resources and load are in reverse distribution, and it is necessary to vigorously develop UHV AC and DC technologies suitable for long-distance and large-power transmission. The pattern of UHV AC-DC hybrid power grid has been initially formed at present. However, the faults of UHV DC with large transmission power and complex fault forms have great impact on the power grid in both active and reactive power. In this paper, based on the analysis of the current situation and characteristics of UHV AC/DC power grids in China, the impact of UHV DC restart and commutation failure on the stability of the power grid is analyzed. The different types and triggering factors of DC commutation failures are analyzed, and the effects of single or multiple DC commutation failure types on the transient angle stability, the voltage stability and the transient overvoltage are simulated. The UHV DC restart fault time sequence is studied, and the effects of different restart modes on the system transient angle stability and transient overvoltage are demonstrated through simulation. The research results have laid the foundation for grasping the UHV DC fault morphology mechanism and the influence law on the stability of the power grid, and provided support for the safe and stable verification of the UHV AC/DC power grid.