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To improve the accuracy of energy consumption analysis of intelligent green building, a new energy consumption simulation analysis method of intelligent green building is proposed. Taking a three-star office building in Changsha as an example, the simulation and actual measurement of building energy saving and annual energy consumption are realized. The results show that the new simulation method can effectively realize the accurate analysis of energy consumption of intelligent green buildings, and provide the basis for energy conservation and consumption reduction of green buildings.

There will be much deep coupling among the large-scale renewable generators, multi-HVDC, and AC system after the system disturbance, in the power system with high proportion renewable energy and multi-send HVDC. As a consequence of that, the risk of cascading failures is greatly increased. Further research on the control strategy of the cascading failure is therefore required. Firstly, time domain simulation is used to search cascading chains with high risk, which is based on action evaluation index of security control devices. So that the actual evolution process of cascading failures can be better expressed in fault chain model. Secondly, a new emergency control method based on searched cascading chains is proposed, to set up emergency control measures for those events that may evolve into cascading failures. This new control method could further strengthen and perfect the ability to block the fault chain of cascading failure of current emergency control system. In order get the lowest risk cost of the control strategy, the preventive control and emergency control is coordinated and optimized. Finally, simulation results and analysis based on real-sized power grid in Northwest China prove the rationality and effectiveness of the proposed control method and strategy.

A design gauge pressure of an eco-friendly gas insulated switchgear (GIS) with an application of vacuum interrupters (VIs) ranges from 0.1 to 0.3MPa. Therefore, a high differential pressure is imposed on bellows of the VIs, which increases the fatigue failure risk of the bellows after cycles of operations. Although, there are some empirical equations recommended by the Chinese National Standard GB/T 12777-2008 which can be used to evaluate the fatigue life of the bellows, there still remains little understanding on the fatigue life of the bellows when the VI is subjected to a high differential pressure and a high operating velocity. The objective of this paper is to determine the relationship between the fatigue life of bellows and high differential pressure and high operating velocity. A fluid-structure interaction simulation is set up to analyze the equivalent stress and the fatigue life of VI bellows under differential gauge pressure ranging from 0.1MPa to 0.3MPa, and under differential operating velocity ranging from 2m/s to 4m/s. The simulation result shows that with an increasing of the pressure and operating velocity, the equivalent stress increases and the fatigue life decreases from 47957 cycles under 0.1MPa and 2m/s to 489 cycles under 0.3MPa and 4m/s. At last, a comparison between the simulation result and the empirical equations shows a limitation of the empirical equations, in which there is lacking of the operating velocity.