Datasheet TB9062FNG (Toshiba) - 7

TB9062FNG • Setting lead angle is performed after starting sensorless operation. During DC excitation and force commutation of start up sequence, lead angle is fixed at 0 °. • We recommend sufficient input PWM signal duty level to prevent motor phase-out. The minimum duty shall be determined by specific motor and its load on the system. • TB9062FNG cannot keep proper sensorless commutation with lower motor rotation speed than setting forced commutation frequency. In that case, TB9062FNG perform next commutation without zero cross detection and motor rotation speed shall become unstable. • Sensorless start up sequence initiate by DC excitation to set fixed position of the motor during the setting time period and after that setting time is up, forced commutation is started by setting frequency. During forced commutation, zero cross point is determined by motor position detected by motor EMF (electromotive force), then TB9062FNG sensorless operation shall commence. Refer to fig. 7.2.1 for the timing chart of operation. Electric angle 0° 60° 120° 180° 240° 300° 360° W⇒V U⇒V U⇒W V⇒W V⇒U W⇒U W⇒V BEMF Ze ro- Ze ro- Ze ro- V crossing crossi ng crossi ng U Ze ro- Ze ro- V crossi ng crossi ng V Ze ro- Ze ro- V crossi ng crossi ng W SW_LA = L Lead angle = 7.5° VU VV VW SW_LA = H Lead angle = 15° VU VV VW
Fig.7.2.1 The timing of 120 degrees sensorless operation
© 2019 7 / 30 Toshiba Electronic Devices & Storage Corporation 2019-08-05