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Taking advantages of both azide and cyanide bridges in magnetism and synthesis, an azido-cyanide mixed-bridged octanuclear [Fe

On account of that common subsynchronous resonance controllers cannot well adapt to the time-varying and nonlinear characteristics of power system, biogeography-based optimization (BBO) algorithm is introduced to design subsynchronous damping controller optimally based on the mechanism of suppressing SSO by static var compensator (SVC). The simulatied results of Jinjie plant indicate that the subsynchronous damping controller optimized by BBO algorithm can remarkably improve the damping of torsional modals and thus effectively depress the multimodal SSO, ensuring the safety and stability of units and power grid operation.

Electrochemical discharge machining (ECDM) is found to be a potential process for the microdrilling of glass wafers. However, some degree of heat-affected zone resulting from the thermal energy during ECDM produces several inherent problems that might be major issues, such as over cut and taper hole. To improve the quality of the ECDM microhole, a flat sidewall–flat front tool electrode is designed to reduce taper phenomena due to the sidewall discharge. In addition, a pulse voltage is applied to improve the heat-affected zone in the rectified dc voltage. The experimental results show that the combination of flat sidewall–flat front tool and pulse voltage conspicuously increases the machining accuracy while retaining the machining rate. This experimental investigation provides a new method that overcomes the disadvantages of conventional ECDM.

Recently, the utilization of pulse voltage has proved to be a potential method for improving the machining accuracy in the microdrilling process by electrochemical discharge machining (ECDM). Although pulse voltage is favorable for improving the machining quality, it is hard to obtain an efficient machining rate. The pulse-off (Toff) duration allows the gas film structure to be re-constructed, which makes the sustainability of a dense gas film difficult and results in unstable and unpredictable discharges. In this study a novel pulse voltage configuration, called offset pulse voltage, has been designed and applied in the ECDM process to improve gas film stability. The offset pulse voltage adds a constant voltage, called offset voltage, at Toff duration to enhance gas film stability and to further promote the discharge performance. The experimental results demonstrated that the increase in offset voltage at the pulse-off duration generates more stable discharges when compared to those generated by the conventional pulse voltage. Results also show that both the mean machining time and time deviation are decreased around 60% without sacrificing machining accuracy by an adequate offset voltage.