Brushless motor apparatus setting mask period on the basis of comparison between voltage of specific coil and voltage of coil other than the specific coil

A method for controlling a brushless motor apparatus, comprising:

• detecting an induced voltage generated in a specific coil while a rotor of a brushless motor rotates, the specific coil being a coil which is not driven by an inverter circuit among a first coil, a second coil, and a third coil, a stator of the brushless motor having the first coil, the second coil, and the third coil which are Y-connected;
• executing comparison between the detected induced voltage and a reference value;
• acquiring a positional signal of the rotor on a basis of a timing when the detected induced voltage is the reference value, the timing being obtained through the comparison;
• switching a coil driven by the inverter circuit among the first coil, the second coil, and the third coil on a basis of the positional signal;
• and
• setting a mask period on a basis of a result of comparison between a voltage of the specific coil and a voltage of a coil other than the specific coil among the first coil, the second coil, and the third coil, wherein the comparison between the induced voltage and the reference value is not executed in the mask period.

A brushless motor apparatus comprising;

• a brushless motor having:
• a rotor having a magnet;
• and
• a stator having a first coil, a second coil, and a third coil which are Y-connected;
• and
• a controller having an inverter circuit configured to selectively drive the first coil, the second coil, and the third coil,
• wherein the controller is configured to:
• detect an induced voltage generated in a specific coil while the rotor rotates, the specific coil being a coil which is not driven by the inverter circuit among the first coil, the second coil, and the third coil;
• execute first comparison between the detected induced voltage and a reference value;
• acquire a positional signal of the rotor on a basis of a timing when the detected induced voltage is a reference value, the timing being obtained through a result of the first comparison;
• switch a coil by the inverter circuit among the first coil, the second coil, and the third coil on a basis of the positional signal;
• and
• set a mask period on a basis of at least one of a result of second comparison and a result of third comparison, the second comparison being comparison between a voltage of the specific coil and a positive side voltage of the invertor circuit, the third comparison being comparison between the voltage of the specific coil and a negative side voltage of the invertor circuit, wherein the first comparison is not executed in the mask period.