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To augment the photovoltaic (PV) power generation conversion, a Maximum Power Point Tracking (MPPT) technique plays a very significant role. This paper introduces a hybrid MPPT-algorithm integrating of Modified Invasive Weed Optimization (MIWO) and Perturb & Observe (P&O) technique under rapid weather change and partial shading scenarios for efficient extraction of the maximum power from the standalone PV-based hybrid system. MIWO handles the initial stages of MPPT followed by the application of the P&O algorithm at the final stages in view of acquiring rapid global peak (GP) and maximal PV power. The studied microgrid comprises of the PV system, battery, electrolyzer, fuel cell, and load. A coordinated DC-voltage regulation and power management strategy between each subsystem of the hybrid microgrid is implemented to save the battery from undesirable charging/discharging operation. Additionally, with the monitoring of DC-voltage, the DC/DC converter associated between the battery and DC-link plays as an MPPT-circuit of the PV without the requirement of an extra dedicated circuit. Takagi-Sugeno (TS)-fuzzy controller is adopted for suppressing/mitigating the voltage oscillations of the microgrid during the variations in solar irradiance/temperature and power demand. The results clearly exhibit the superior performance of the proposed methodology compared to some of the existing techniques.

The integration of large-scale wind power into weak power systems raises several issues that must be clarified.Typically these include the practical connection to the network, integration with the network system, system stability, system operation, necessary installations and extensions of the network, etc. At the same time, careful attention must be paid to the functional requirements such wind farms should meet in order to enhance system responses. Different wind power technologies have different characteristics and control possibilities. In this article, three technologies have been studied with respect to their dynamic performance, and a transient stability study has been performed in order to illustrate the differences in the three technologies. The results clearly show that there are differences in behaviour and in control possibilities. Hence there are also differences in how well they can meet functional requirements.When discussing to what degree strict requirements should be imposed on wind power, it should be kept in mind that some requirements can be met with small or moderate costs, while others may be expensive or difficult to meet. Some requirements may also mean a reduction in generation and hence in revenues. Rather than imposing strict requirements on wind turbines as such, ancillary services should be met in the most suitable way. It is not obvious that the same requirements should apply to wind power in hydro power-dominated systems compared with, for instance, systems with a large share of nuclear or thermal power. It may well be cheaper to incorporate primary power control and system-stabilizing equipment in other power plants or grid points than in many small wind turbine generators. General conclusions cannot be made on this, but the issue should be the focal point of system operators everywhere. Copyright

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