Current detection apparatus and manufacturing method of the same

A manufacturing method for a current detection apparatus that has magnetic sensors each disposed to face each of current paths for each of windings with 2n phases (n is a multiple of three) in an AC rotating machine, the manufacturing method for the current detection apparatus comprising the steps of:

• setting 2n current path arrangement positions as positions for setting 2n current paths in which each of the magnetic sensors is disposed to face each of the 2n current paths;
• assigning each of the 2n current paths to which each of the magnetic sensors is disposed to face, at each of the 2n current path arrangement positions that are set, so as to satisfy at least one of a first condition and a second condition,
• wherein, in a case where a detection current iks that is detected by a magnetic sensor disposed to face a current path of a k-phase is represented by Formula (b) using a current Il of an l-phase (l=1 to 2n) being a l-th phase out of the 2n phases and using al_k that is a coupling coefficient between a current path of the l-phase and the magnetic sensor disposed to face the current path of the k-phase (k=1 to 2n) being the k-th phase out of the 2n phases,
• i
• ks
• =
• ∑
• l
• =
• 1
• 2
• ⁢
• n
• ⁢
• ⁢
• a
• l
• ⁢
• _
• ⁢
• k
• ×
• I
• l
• ⁢
• ⁢
• (
• k
• =
• 1
• ∼
• 2
• ⁢
• n
• )
• (
• b
• )
• and in a d-axis sum current and a q-axis sum current that are currents obtained by performing a dq-transformation into a two-axis coordinate system on 2n detection currents iks on an assumption that all amplitudes of Il are the same, and when each of a DC component and an AC component in the sum currents is represented collectively with each of terms expressed by sine functions with different phases to one another,
• the first condition is a condition in which, at least in one of the terms, an amplitude in the one term corresponding to one of error components is reduced by cancellation among coefficients al_k included in the one term, where l≠k, and
• the second condition is a condition in which the error components are reduced by cancellation among values of the terms of sine functions with different phases;
• and
• arranging each of the current paths to which each of the magnetic sensors is disposed to face, at the current path arrangement positions assigned in the step of assigning each of the 2n current paths.