| 摘要 |
A method for estimating the rotor time constant (tau<SUB>r</SUB>) of an induction machine when the stator resistance (R<SUB>s</SUB>) and rotor resistance (R<SUB>r</SUB>) of the induction machine are known. The method comprises the steps of feeding a DC current to the stator of the induction machine, injecting a sine-wave current component into the stator of the induction machine, the current having an amplitude (i<SUB>sc</SUB>) and an angular frequency (omega<SUB>c</SUB>), measuring the voltage component (u<SUB>scd</SUB>) of the stator voltage of the induction machine in the same direction and with the same angular frequency as the injected current, and calculating the rotor time constant using equation <maths id="MATH-US-00001" num="1"> <MATH OVERFLOW="SCROLL"> <MROW> <MSUB> <MI>tau</MI> <MI>r</MI> </MSUB> <MO>=</MO> <MROW> <MFRAC> <MN>1</MN> <MSUB> <MI>omega</MI> <MI>c</MI> </MSUB> </MFRAC> <MO></MO> <MROW> <MSQRT> <MFRAC> <MROW> <MSUB> <MI>u</MI> <MI>scd</MI> </MSUB> <MO>-</MO> <MROW> <MSUB> <MI>R</MI> <MI>s</MI> </MSUB> <MO></MO> <MSUB> <MI>i</MI> <MI>sc</MI> </MSUB> </MROW> </MROW> <MROW> <MROW> <MROW> <MO>(</MO> <MROW> <MSUB> <MI>R</MI> <MI>s</MI> </MSUB> <MO>+</MO> <MSUB> <MI>R</MI> <MI>R</MI> </MSUB> </MROW> <MO>)</MO> </MROW> <MO></MO> <MSUB> <MI>i</MI> <MI>sc</MI> </MSUB> </MROW> <MO>-</MO> <MSUB> <MI>u</MI> <MI>scd</MI> </MSUB> </MROW> </MFRAC> </MSQRT> <MO>.</MO> </MROW> </MROW> </MROW> </MATH> </MATHS>
|
