UM0324 datasheet(30/105 Pages) STMICROELECTRONICS

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Running the demo program

UM0324

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However, if the motor does not reach the above mentioned speeds before

STARTUP_RAMP_DURATION

, the final torque reference value (STARTUP_FINAL_TORQUE)

is further applied until STARTUP_TIMEOUT. Finally, in the case where the speeds that

enable the closed loop are not reached before STARTUP_TIMEOUT, the state machine goes

into FAULT state for two seconds and the error message Start-up failed is displayed on the

LCD. In this case, it is strongly advised to check speed sensor feedback connections first

and then, if necessary, to increase STARTUP_FINAL_TORQUE if the load torque is too high.

With reference to Figure 15, note that parameters TACHO_SPEED_VAL,

ENCODER_CL_ENABLE

, STARTUP_FINAL_TORQUE, STARTUP_RAMP_DURATION, and

STARTUP_TIMEOUT

are fully configurable so that you can customize the start-up depending

on the motor and load conditions. Parameters definitions are done in the

MC_Control_Param.h

header file.

Figure 15.

Closed loop start-up strategy

3.3

Setting up the system when using ICS sensors

The default configuration provides for the use of three shunt resistors and tacho-generator.

Section 3.3.1 describes how to change the firmware configuration from three shunt resistors

to two ICS stator current reading. This section gives you information about how to provide

the STR750 with ICS feedback signals and to properly customize the firmware.

Caution:

When using two ICS for stator current reading, you must ensure that the conditioned

sensors output signal range is compatible with the STR750 supply voltage.

UM0324 датащи(PDF) 30 Page - STMicroelectronics