Abstract: A method of optimizing one or more starting parameters of a solar power generator system and a solar power generator system, wherein the solar power generator system includes a solar panel array and a converter for converting power obtained from the panel array. The method can include measuring an output voltage of the panel array, comparing the output voltage with a starting voltage (Vdc), starting the solar power generator system when the output voltage of the panel array exceeds the starting voltage (Vdc), measuring the obtained power from the solar panel array after a morning start, comparing the obtained power with a known limit value, and changing the one or more starting parameters on the basis of the comparison of power.

Abstract: A method and an arrangement are disclosed for detecting islanding operation of a distributed power generator. The method can include determining a frequency of a grid to which the distributed power generator is connected, measuring a rate of change of the frequency of the grid at an output of the distributed power generator, determining a threshold value for an alteration speed, comparing the rate of change of the frequency of the grid with the threshold value, and detecting islanding operation when the measured rate of change of the frequency exceeds the threshold value for a certain time period.

Abstract: A method and an arrangement of tracking a selected (e.g., maximum) power point of a photovoltaic system is disclosed, in which method an operation point of the photovoltaic system is changed based on the change of operation point and a change of power generated by the photovoltaic system. The method can include repeatedly determining a current or voltage of the photovoltaic system, determining a power of the photovoltaic system, determining a change of power of the photovoltaic system with respect to a previous determined power, and changing the operation point of the photovoltaic system by changing a current or voltage reference of the system stepwise depending on the change of power and a direction of a previous change of the current or voltage reference.

Abstract: A method and arrangement of determining starting conditions of a solar converter in a photovoltaic system. The photovoltaic system includes a photovoltaic panel system having one or more photovoltaic panels. The method includes determining an open circuit voltage of the photovoltaic panel system, and determining beforehand limit values for the starting conditions, where the limit values include an open circuit voltage value and a temperature value, with which values the solar converter can be started. The method also includes determining beforehand the temperature dependency of the open circuit voltage of the panel system, determining a temperature of the panel system, and setting a criterion for starting the converter. The criterion includes determining, by using the determined temperature dependency and the determined limit values for the starting conditions, whether the determined temperature and the determined open circuit voltage enable the starting of the converter.

Abstract: A method of optimizing one or more starting parameters of a solar power generator system and a solar power generator system, wherein the solar power generator system includes a solar panel array and a converter for converting power obtained from the panel array. The method can include measuring an output voltage of the panel array, comparing the output voltage with a starting voltage (Vdc), starting the solar power generator system when the output voltage of the panel array exceeds the starting voltage (Vdc), measuring the obtained power from the solar panel array after a morning start, comparing the obtained power with a known limit value, and changing the one or more starting parameters on the basis of the comparison of power.

Abstract: A method and an arrangement of tracking a selected (e.g., maximum) power point of a photovoltaic system is disclosed, in which method an operation point of the photovoltaic system is changed based on the change of operation point and a change of power generated by the photovoltaic system. The method can include repeatedly determining a current or voltage of the photovoltaic system, determining a power of the photovoltaic system, determining a change of power of the photovoltaic system with respect to a previous determined power, and changing the operation point of the photovoltaic system by changing a current or voltage reference of the system stepwise depending on the change of power and a direction of a previous change of the current or voltage reference.

Abstract: A method and an arrangement are disclosed for detecting islanding operation of a distributed power generator. The method can include determining a frequency of a grid to which the distributed power generator is connected, measuring a rate of change of the frequency of the grid at an output of the distributed power generator, determining a threshold value for an alteration speed, comparing the rate of change of the frequency of the grid with the threshold value, and detecting islanding operation when the measured rate of change of the frequency exceeds the threshold value for a certain time period.

Abstract: A method and arrangement of determining starting conditions of a solar converter in a photovoltaic system. The photovoltaic system includes a photovoltaic panel system having one or more photovoltaic panels. The method includes determining an open circuit voltage of the photovoltaic panel system, and determining beforehand limit values for the starting conditions, where the limit values include an open circuit voltage value and a temperature value, with which values the solar converter can be started. The method also includes determining beforehand the temperature dependency of the open circuit voltage of the panel system, determining a temperature of the panel system, and setting a criterion for starting the converter. The criterion includes determining, by using the determined temperature dependency and the determined limit values for the starting conditions, whether the determined temperature and the determined open circuit voltage enable the starting of the converter.