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This paper proposes a distributed finite-time secondary controller to achieve average voltage regulation and proportionate current sharing within a finite settling time for autonomous network of dc microgrids. It is employed by using a distributed finite-time control approach which maintains average voltage regulation of the system facilitating proportionate current sharing simultaneously by virtue of dynamic consensus between its neighbors. The proposed scheme ensures an improved performance over the conventional distributed secondary methods by reducing overshoots and chattering which is significant for critical operation of the loads. The proposed control strategy is simulated in MATLAB/Simulink environment to test link-failure resiliency, plug and play capability, and controller performance under communication delays within a tolerable upper bound on delay determined using time-delay analysis. Moreover the effect of variable time delays in different transmission medium is also simulated to test the practicality of the approach. This strategy is further tested on a 500-W FPGA-based experimental prototype to validate the control approach under different scenarios.

This paper proposes a distributed finite-time secondary controller to achieve average voltage regulation and proportionate current sharing within a finite settling time for autonomous network of dc microgrids. It is employed by using a distributed finite-time control approach which maintains average voltage regulation of the system facilitating proportionate current sharing simultaneously by virtue of dynamic consensus between its neighbors. The proposed scheme ensures an improved performance over the conventional distributed secondary methods by reducing overshoots and chattering which is significant for critical operation of the loads. The proposed control strategy is simulated in MATLAB/Simulink environment to test link-failure resiliency, plug and play capability, and controller performance under communication delays within a tolerable upper bound on delay determined using time-delay analysis. Moreover the effect of variable time delays in different transmission medium is also simulated to test the practicality of the approach. This strategy is further tested on a 500-W FPGA-based experimental prototype to validate the control approach under different scenarios.

Battery energy storage (BES) is attracting increasing attention for balancing variable renewable electricity (VRE) production in mainland power systems. However, the application of storage systems is argued to be even more relevant in islands or isolated systems which suffer more acutely from existing challenges in power system management. This paper investigates the use of storage for the island of Jersey, primarily in for two applications; reducing exposure to peak pricing over the existing interconnector to France, and also deferring or removing completely the need to use of on-island generation to supply peak loads. The results demonstrate that an investment in energy storage cannot be justified merely by the benefits from making profits from these applications. However, we consider how the investment equation could change as the cost of BES falls into the future and if it can provide additional benefits such as avoidance of the cost of replacement generation.

Battery energy storage (BES) is attracting increasing attention for balancing variable renewable electricity (VRE) production in mainland power systems. However, the application of storage systems is argued to be even more relevant in islands or isolated systems which suffer more acutely from existing challenges in power system management. This paper investigates the use of storage for the island of Jersey, primarily in for two applications; reducing exposure to peak pricing over the existing interconnector to France, and also deferring or removing completely the need to use of on-island generation to supply peak loads. The results demonstrate that an investment in energy storage cannot be justified merely by the benefits from making profits from these applications. However, we consider how the investment equation could change as the cost of BES falls into the future and if it can provide additional benefits such as avoidance of the cost of replacement generation.

Production of biomass and phycocyanin (PC) were investigated in highly pigmented variants of the unicellular rhodophyte Galdieria sulphuraria, which maintained high specific pigment concentrations when grown heterotrophically in darkness. The parental culture, G. sulphuraria 074G was grown on solidified growth media, and intensely coloured colonies were isolated and grown in high-cell-density fed-batch and continuous-flow cultures. These cultures contained 80-110 g L(-1) biomass and 1.4-2.9 g L(-1) PC. The volumetric PC production rates were 0.5-0.9 g L(-1) day(-1). The PC production rates were 11-21 times higher than previously reported for heterotrophic G. sulphuraria 074G grown on glucose and 20-287 times higher than found in phototrophic cultures of Spirulina platensis, the organism presently used for commercial production of PC.

Production of biomass and phycocyanin (PC) were investigated in highly pigmented variants of the unicellular rhodophyte Galdieria sulphuraria, which maintained high specific pigment concentrations when grown heterotrophically in darkness. The parental culture, G. sulphuraria 074G was grown on solidified growth media, and intensely coloured colonies were isolated and grown in high-cell-density fed-batch and continuous-flow cultures. These cultures contained 80-110 g L(-1) biomass and 1.4-2.9 g L(-1) PC. The volumetric PC production rates were 0.5-0.9 g L(-1) day(-1). The PC production rates were 11-21 times higher than previously reported for heterotrophic G. sulphuraria 074G grown on glucose and 20-287 times higher than found in phototrophic cultures of Spirulina platensis, the organism presently used for commercial production of PC.

Chaotic switching is a newly evolve randomization method which suppress the conducted electromagnetic interference generated within the DC-DC converter. It can also suppress the spectral peaks present in the frequency band effectively by spread spectrum technique and spread it over the wide range of frequency band implying electromagnetic interference (EMI) suppression. In this article, a chaotic pulse width modulation technique based on randomized carrier frequency modulation with fixed duty ratio is generated through field programable gate array for suppressing the conducted electromagnetic interference generated within the Luo-converter. A hardware prototype of Luo-converter is developed in order to analyze EMI reduction through power spectral density analysis by comparing both traditional periodic PWM switching and chaotic PWM switching. The results obtained from the hardware setup shows significant reduction of EMI with chaotic switching as compared to traditional pulse width modulation switching under both boost and buck operation of Luo-converter.

Chaotic switching is a newly evolve randomization method which suppress the conducted electromagnetic interference generated within the DC-DC converter. It can also suppress the spectral peaks present in the frequency band effectively by spread spectrum technique and spread it over the wide range of frequency band implying electromagnetic interference (EMI) suppression. In this article, a chaotic pulse width modulation technique based on randomized carrier frequency modulation with fixed duty ratio is generated through field programable gate array for suppressing the conducted electromagnetic interference generated within the Luo-converter. A hardware prototype of Luo-converter is developed in order to analyze EMI reduction through power spectral density analysis by comparing both traditional periodic PWM switching and chaotic PWM switching. The results obtained from the hardware setup shows significant reduction of EMI with chaotic switching as compared to traditional pulse width modulation switching under both boost and buck operation of Luo-converter.