| 摘要 |
PURPOSE:To restrict maximum current within a limit level during deceleration while increasing maximum torque during acceleration. CONSTITUTION:A torque command Tcmdl is determined(S1) and if it does not exceed a predetermined limit value Ko during acceleration, the torque command Tcmdl is outputted as a torque command(current command) Tcmd2 for current loop(S2, S3, S9, S10). If the limit value Ko is exceeded, amplitude Io of actual current is determined(S5) and then a limit value L is determined based on the limit value Ko and the magnitude R(T) of a torque command Tcmd2 obtained one period before(S6). The torque command Tcmd1 is then clamped by the limit value L thus producing the torque command Tcmd2 for current loop. Steps S4-S8 are executed at the time of deceleration. Since the limit value L is determined from the ratio between the current command and the amplitude of actual current during acceleration and the torque command Tcmd is clamped at that value, amplitude of actual current does not decrease thus increasing output torque. If the actual current increases due to counter- electromotive force during deceleration, the limit value L decreases to decrease the command thus restricting the actual current within a limit value. |
