Synchronous Spindle Motor Drive
EDT. DATE DESIG. DESCRIPTION PAGE /29
02 2003.10.15 K.Takahashi
dded SSM etc. Y.Toyozawa
03 2004.06.09 K.Takahashi Revised Pole detect, etc. Y.Toyozawa
7.5 Pole detection motion
In the pole detect sequence, the motor moved as the follows when Pole detection is executed.
7.5.1 Case 1: Auto mode (9D53/C, 9D70/B or later)
Auto mode finds the pole-position of motor by the combination of the two modes. Two modes are Minute
moving mode and Stop state mode.
The feature of Auto mode is the next. It is possible to detect the pole position by the minute moving of motor
motion, and the pole position can be detected even if the motor is the lock state.
But, in case of using Stop state mode (the digit 4,3 of No.4083 =0), the following 2 conditions must be satisfy
for applying this function. If these conditions can’t be satisfied, the pole detection accuracy may be become to
• Motor inductance Lq and Ld is different more than 1mH ( Lq – Ld > 1mH )
• The magnetic saturation more than 5% can be observed by 70% of maximum current.
Auto mode executed as the follows.
(1) SPM executes Minute moving mode at first. If the motor moves at the early 2 operations, SPM continues
Minute moving mode. And then, SPM sets the pole position status signal to “1” after the pole position is
(2) If the motor doesn’t move at the early 2 operations of Minute moving mode, SPM judges the motor as the
lock state and SPM changes the pole detection mode from Minute moving mode to Stop state mode. And
then, SPM sets the pole position status signal to “1” after the pole position is detected.
7.5.2 Case 2: DC current mode
DC current mode is executed as the follows. The angle is showed by the electrical angle (= machine angle *
pole-pairs) in the following explanation.
, the motor is excited at 0-degree position (electrical position). The excitation current changes as the
(2) Confirms the motor stop. (The time of parameter No.4083(16i) lower digit is passed after motor speed
becomes less than 5min-1)
(3) Next, the motor is excited at 90(or 120)-degree position (electrical position).
(4) Confirms the motor stop.
(5) Confirms the moving distance from 0-degree point to 90(or 120)-degree point. If the moving distance is
beyond the range (80 to 100 degree or 110 to 130degree), AL-65 is generated.
The motor will stop with the vibration because the pole detection is the movement as above mode.
Maximum moving angles is 270 degrees (electrical angle) during time from start to finish of the pole detection.
Case of software except 9D53/C, 9D70/B o
Final current =4
Time constant =4
Possible by 9D53/C, 9D70/B or later