Abb Industry Oy

Mikko Norrkniivil&auml;

Samuli Heikkil&auml;

A method for controlling an inverter which comprises the switching components to be controlled, the method comprising the steps of determining a current vector ({overscore (i)},) for the inverter output; determining a flux vector ({overscore (&psgr;)}) for the inverter load; determining an angular speed (&ohgr;) for the inverter load; determining a resistance (R) for the inverter load. The method further comprises the steps of determining a voltage vector ({overscore (b)}) as a sum of the product of the inverter load resistance (R) and the output current vector ({overscore (i)},) and a voltage proportional to the electromotive force of the load; forming a direction vector ({overscore (S)}) on the basis of a current vector ({overscore (i)},) for the inverter reference value and the inverter output current vector ({overscore (i)},); determining a space coordinate system &mgr;&ugr; associated with the voltage vector ({overscore (b)}) and having a real axis &mgr; which is co-directional with the voltage vector ({overscore (b)}); determining the direction vector ({overscore (S)}) in the &mgr;&ngr; coordinates system; and forming inverter switch commands on the basis of a component ({overscore (S)},) co-directional with the &mgr; axis of the direction vector ({overscore (S)}) and a component ({overscore (S)},) co-directional with the &ugr; axis.

Growing community of inventors

Masala, Finland

Mikko Norrkniivilä

Growing community of inventors

Masala, Finland

Mikko Norrkniivil&auml;

Mikko Norrkniivilä