BEMF传感<3500RPM的12极BLDC电机的最大转速？

如果使用霍尔接口而不是bemf传感方法，您可以获得电机可以具有的最大可用转速。 Bemf检测需要更多的计算时间，这可能会在限制最大转速的反馈回路上产生延迟。



以下为原文





in case using hall interface rather than bemf sensing method you can get maximum available rpm s that your motor can  have. Bemf sensing need more computational time and this may get a delay on feedback loop that restrict maximal rpm.

假设电机是12极对（不是12极），那么机电比为12，所以我们有
120机械Hz变为1440电Hz
 
 180机械Hz变为2160电Hz。在后一种情况下，我们在两个换向事件之间具有2160×6 = 12960Hz的步进时间频率。
然后我们可以催眠我们每个PWM周期都有序列（换向，退磁，零交叉，换向），我们需要设置38.8kHz的PWM频率。
第一个问题是：STM8可以完成这项工作吗？
使用验证文档中报告的数据，我发现在25.72us的周期内中断延迟和执行时间之间需要14us。因此，似乎可以使用54.4％的工作量来执行该作业。
第二个问题是：考虑到取决于功率级的稳定时间，这些值几乎是可能的吗？只有一个PWM周期足以实现良好的过零检测？
我认为680Hz的电频率（如你提到的线程中所解释的）可以更加真实。
如果我们想要保持无传感器控制的附加值，另一个建议可以是使用例如STM32值线来分析正弦控制的可能性。
抱歉回复晚了。
 最好的问候
 梁咏琪



以下为原文






Let assume that the motor is 12 poles pairs (not 12 poles) then the mechanical to electrical ratio is 12 so we have
120 mechanical Hz becomes 1440 electrical Hz

180 mechanical Hz becomes 2160 electrical HzIn the latter case we have a step time frequency of 2160 x 6 = 12960 Hz between two commutation event.
Then we can hypnotize that we have the sequence (Commutation, Demagnetization, Zero crossing, Commutation) each PWM cycle, we need to set 38.8kHz of PWM frequency.
First question is: can STM8 do the job?
Using the data reported in the validation document I see that it is required 14us between interrupt latency and execution time over a period of 25.72us. So it seems that the job can be performed using 54.4% of workload.
Second question is: these values are practically possible considering the stabilization time that depend on the power stage? And only one PWM period can be sufficient to achieve a good zero crossing detection?
I think that the electrical frequency of 680Hz (as explained in the thread you mention) can be more realistic.
Another suggestion, if we want to preserve the added value of the sensorless control, can be to analyze the possibility of a sinusoidal control using for instance a STM32 value line.
Sorry for the late answer.
Best regard
Gigi

嗨吉吉，
 
我有一个像这样的BLDC型号EMAX CF2822：
http://www.rcsmart.com.my/webshaper/store/viewProd.asp?pkProductItem=796
 
我读过这个电机的地方是12极（我不知道它是12极对还是6极对，我猜6）。
你认为可以使用stm8来驱动这个电机吗？
 
最好的祝福，
 马克斯



以下为原文





Hi Gigi,

I've a BLDC model EMAX CF2822 like this one:
http://www.rcsmart.com.my/webshaper/store/viewProd.asp?pkProductItem=796

Somewhere I've read this motor is 12 poles (I don't know if it's 12 pole pairs or 6 pole pairs, I suppose 6).
Do you think it's possible to use the stm8 to drive this motor?

Best regards,
  Max

极数和其他电机参数不受stms bldc电机控制库的限制。如果在那里霍尔反馈你必须通过相关的霍尔传感器代码使用头文件定义极数。
 
 基本上你有三根电缆用三相换向方案驱动你的电机。根据功率要求，您可以适应功率级。



以下为原文





Number of poles nor other motor parameters is not  restricted  by stms bldc motor control library. incase there where hall feddback you must define number of poles via related hall sensor code using header files.

basically you have three cable to drive your motor with three phase commutated scheme. according to power requirement you can adapt power stage.

总结Murat和Gigi的回复
 
 在霍尔传感器的情况下 - ＆gt;没问题，
 在无传感器的情况下，如果使用38.8kHz PWM频率并接受约55％的CPU负载，则可以使用STM8S
 
 问候，
 Billino



以下为原文







Summarizing Murat and Gigi's replies

In case of Hall sensors -> no problems,
in case of sensor-less, it's possible to use STM8S if you use 38.8kHz PWM frequency and accept CPU load of about 55%

Regards,
Billino