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This paper introduces a new method that no previous study has been done in this photovoltaic power generation similar to this paper to harness maximum potential power from photovoltaic power generation. The completely mathematical model added the relation between diode factor of the generation and p-n junction temperature is proposed to use in this method. The maximum power point tracker combines the iterative and bisectional technique, the completely mathematical model of PVgPVG and the system of equations that converts value of parameters from standard test condition to any working condition, measuring sensors to measure power of solar irradiance and p-n junction temperature to determine parameters at maximum power point at any working condition. The voltage controller is designed to drive this generation to expect working state to harness maximum power. An experimental model corresponding to this method was designed and operated in real conditions in Viet Nam. Experimental results show the high accuracy of analyzing in theory and high capability to bring this method out real applications to harness all available energy of this generation.

This paper presents a novel approach to complete the mathematical model for photovoltaic power generation. In this approach, the relation between the diode factor and temperature at p-n junction is added into the its mathematical model corresponding to each structure of this generation made from semiconductors. Using calculation results from the iterative and bisectional technique to determine maximum power point, the system of equations converting some parameters from standard test condition to any operational condition, datasheet published by manufacturers, the mathematical model is tested to ensure that the diode factor only depend on temperature at p-n junction. Moreover, the least square method is used to create the function representing this relation from only some pair-values. Calculated results of the proposed modeling that applied in a MF165EB3 panel show the high accuracy about value of maximum power and good meaning in control when using results of iterative and bisectional technique at any operational condition.

This paper focuses on the effect of transformer parameters and a line reactor on distribution of power flows in a high-voltage substation and transmission lines. Four case studies that have different values of transformer parameters including rated power, short-circuit impedance and reactance/resistance ratio are supposed in this research. Basing on power flows on transformers in case of the parallel operation, load factor of each transformer and operating parameters are considered in above case studies. Moreover, a line reactor is proposed in this paper to regulate power flows in a system having two power sources. Four operating modes of the proposed line reactor are defined by changing on/off states of switches in this device to modify the value of impedance. The effect of the line reactor on power received from sources and power flows on transmission lines is evaluated in its all modes. Research results are carried out by the ETAP 16.0 software and present high accuracy and reliability for the proposed problems. Research contributions help dispatchers understand the essence of power transmission process, solve real problems and give out effective solutions to operate high-voltage systems.

This paper introduces a new method, called IB-SMC method, to control DC/DC boost converters in systems exploiting photovoltaic power generation. This method combines the sliding mode control technique and iterative-bisectional technique in the maximum power point tracker to change operations modes of photovoltaic power generation. The IB-SMC controller uses voltage sliding surface to evaluate the relation of instantaneous voltage at the input converter and instantaneous voltage at the maximum power point. Using information about the power of electromagnetic radiation from a pyranometer and temperature from a temperature sensor, the sliding surface and hyteresis band are changed by practically operational conditions that help improving energy efficiency of the process exploiting PVg. Simulations are carried out by Matlab/Simulink that show the ability to ensure dynamic stability by tracking instaneous maximum power point at any time whenever having any change of the operational condition, static stability by maintaining the operation point at maximum power point whenever not have any change of the operational condition and help to bring out approximately absolute energy efficiency.

In power systems having photovoltaic generations, controlling the optimal energy is executed by maximum power point algorithms. Most of these algorithms require the information of equivalent photovoltaic parameters such as series and parallel resistor, photo-generated current, reserve saturation current, thermal voltage.