METHOD AND ARRANGEMENT FOR OPERATING A PUMP

摘要

A method and arrangement for operating a pump system are disclosed, the pump system including a pump arranged to be rotated with an AC motor, an inverter, the output of which is electrically connected to the AC motor, and a photovoltaic panel system electrically connected to feed DC power to the inverter. The method can include setting a voltage limit, and determining continuously voltage obtained from the photovoltaic panel system. When the determined voltage of the photovoltaic panel system is below the set voltage limit, frequency of the inverter can be controlled such that the ratio between output voltage of the inverter and the output frequency is substantially constant. When the determined voltage of the photovoltaic panel system exceeds the voltage limit, the inverter frequency can be controlled for keeping voltage of the photovoltaic panel system substantially at the voltage limit.

主权项

1. A method of operating a pump system having a pump arranged to be rotated with an AC motor, an inverter, an output of which is electrically connected to the AC motor, and a photovoltaic panel system electrically connected to feed DC power to an inverter, the method comprising:
setting a voltage limit (Vboost); determining continuously a voltage obtained from the photovoltaic panel system; when the determined voltage of the photovoltaic panel system is below the set voltage limit, controlling an output frequency of the inverter such that a ratio between an output voltage of the inverter and the output frequency is substantially constant; and when the determined voltage of the photovoltaic panel system exceeds the voltage limit (Vboost), controlling the output frequency of the inverter for keeping the voltage of the photovoltaic panel system substantially at the voltage limit.