![bldc tool detection failed bldc tool detection failed](https://www.infineon.com/export/sites/default/_images/product/evaluation-boards/BLDC_SHIELD_TLE956X.jpg)
![bldc tool detection failed bldc tool detection failed](https://hackaday.com/wp-content/uploads/2018/04/bldc.png)
In thisscheme, there is a period of 120 degrees of rotation in which, forexample, phase U does not create any torque on the rotor. Lower switchesare turned on and off to provide the path for current flow. Phase Up is on for 120 degrees Vp is on for the next 120degrees and finally Wp is on for the rest of the cycle.
![bldc tool detection failed bldc tool detection failed](http://vedder.se/wp-content/uploads/2014/08/start_d5_almost_auto_voltage.png)
Each phase isenergized for a time that corresponds to 120 degrees of electricalrotation. Progression of six coil energization steps.Īnother way to understand 120-degree modulation is to look at thetiming of Up, Vp, and Wp during electrical rotation. The progression of six-step coil energization is shown in Figure 29, below.įigure29. This switchingeffectively keeps the V coil free of current for the next 60 degrees.During this period when no current flows in the V coil, the back-EMFsignal generated by the rotor's magnetic field can be detected in the Vcoil. Every 60 degrees we switch connections so that thecurrent flowing from coil U to V now flows from U to W. Recall that for six-step 120-degree modulation, power switches areturned on and off so that the current passes through two coils, asshown in Figure 28. Later we willdiscuss open-loop V/f control and closed-loop control, as well as a fewlast words on vector control.
#BLDC TOOL DETECTION FAILED CODE#
We will also discuss sinusoidal modulation including anexample of code used to generate a sine wave as well. Building on the fundamentals of BLDC motor operation andcontrolcovered in Part 1, Part2and Part3 in this series, let's now turn ourattention to putting this knowledge to work, shifting from the earliersix-step 120-degree modulation to an examination of 180-degreemodulation.