ZHCSP55A October 2019 – October 2021 DRV10982-Q1
PRODUCTION DATA
For any given motor, the integrated value of BEMF during half of an electrical cycle is constant. The value is determined by the BEMF constant (KtPH) (see Figure 8-30). The BEMF constant is the same regardless of whether the motor is running fast or slow. This constant value is continuously monitored by calculation and used as a criterion to determine the motor lock condition, and is referred to as Ktc.
Based on the KtPH value programmed, create a range from Kt_low to Kt_high. If Ktc goes beyond the range for a certain period of time, tLCK_ETR, lock is detected. Kt_low and Kt_high are determined by KtLckThr[1:0] (see Figure 8-31).