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During the transient period of large-disturbance of the received power grid, the power features of the inverter are of great important for the security and stability of the system. The research before is defective in that the constant control mode assumption and the rough HVDC simulation model. The paper establishes the PSCAD/EMTDC model for Yun-Guang EHVDC system, and analysis the transient real power and the reactive power of the inverter. With the analysis of logic for control mode, the author also introduces the physical processes of the peak of the reactive power. At last, the paper puts forward several strategies for suppressing the peak of the dynamic reactive power and real power recovery acceleration.

Multiple loop heat pipes which have two evaporators and two condensers in one loop are a kind of active heat transfer device. Since they have two evaporators and two condensers, the operating mode also becomes multiple. This work discusses the cases that multiple loop heat pipes were operated with one condenser at high temperature and the other at low temperature. To avoid the high temperature returning liquid and keep the multiple loop heat pipes work properly, the flow regulator which was made of polyethylene was designed, fabricated and applied in this test. The effect of flow regulator was confirmed and analyzed. In the test that large temperature difference existed between two sinks, it can be found according to the result that the flow regulator worked effectively and prevented the high temperature vapor to enter the inlet of common liquid line, which can keep the evaporators and returning liquid to operate at low temperature. With the increment of heat loads and the temperature difference between two sinks, the pressure difference between two condensers became larger and larger. When the pressure difference was larger than the flow regulator's capillary force, the flow regulator could not work properly because the high temperature vapor began to flow through the flow regulator. According to the test data, the flow regulator can work properly within the sinks' temperature 0˚C/60˚C and the two evaporators' heat load 30/30 W.