| 摘要 |
<P>PROBLEM TO BE SOLVED: To correctly estimate a rotor frequency in a very low speed range. <P>SOLUTION: According to an induction machine simulator numeric expression model, an induction machine simulator section 30 estimates a primary d-axis current I<SB>1d</SB>and a primary q-axis current I<SB>1q</SB>, based on an inverter frequency f<SB>1</SB>and voltage output command values V<SB>1d</SB><SP>*</SP>, V<SB>1q</SB><SP>*</SP>. A difference obtained by subtracting a primary q-axis current actually measured from a primary q-axis current estimation value I<SB>1qest</SB>estimated by computation is inputted to a proportional integrator 40. The proportional integrator 40 proportionally integrates the input value and outputs the result of this integration as a frequency compensation value Δf<SB>rest</SB>. The frequency compensation value Δf<SB>rest</SB>outputted from the proportional integrator 40 is added to a rotor frequency estimation value f<SB>rest0</SB>outputted from a mechanical simulator section 20 to compensate the rotor frequency estimation value. <P>COPYRIGHT: (C)2007,JPO&INPIT |
