摘要 |
<p>A blower control device changes a PQ characteristic in a second table so that an operating point (QN, PN) on the PQ characteristic in the second table agrees with an operating point (Q0, P0) on a PQ characteristic in a first table. At this time, the blower control device changes the PQ characteristic in the second table at a rate based on QN and Q0. Furthermore, the blower control device changes a load noise characteristic in the second table at a rate based on QN and Q0. Then, the blower control device calculates load noise corresponding to the operating point (Q0, P0) with respect to each rotation frequency ratio from the changed load noise characteristic. And then, the blower control device determines a rotation frequency ratio corresponding to the lowest load noise as a rotation frequency ratio at which a plurality of fans is rotated.</p> |