L6482H法获得良好的扭矩

嗨，
 
 
L6482H的默认配置不允许良好的性能。
首先，栅极驱动配置（GATECFG1和GATECFG2）不适用于STP35NF10 MOSFET。
我建议以下配置：
- IGATE = 64mA
- TCC = 1us（IGATE x TCC应> MOS的Qg）
- TDT = 250 ns
- TBLANK = 375 ns
 
还应调整当前控制配置：
- TON_MIN = 3.5我们
- TOFF_MIN = 21我们
- TOFF_FAST = 10我们
- FAST_STEP = 16我们
- TSW = 48 us
 
使用此配置，您应该获得更好的结果。
 
问题1：预测电流控制在step_mode中工作???
是的，当它启用时，它始终处于活动状态。
问题2：可以修改tcc，tdt，tblank寄存器以在高转速时获得更好的扭矩吗？
高速转矩通常受电源电压和电机特性的限制（转速越高，越难以迫使电流进入电机相）。对于TCC，IGATE等配置，请参见前一点。
 
BR
恩里科



以下为原文





Hi,


the default configuration of the L6482H doesn't allow good performance.
First of all, the gate driving configuration (GATECFG1 and GATECFG2) is not suitable for the STP35NF10 MOSFETs.
I suggest the following configuration:
- IGATE = 64mA
- TCC = 1us (IGATE x TCC should be > of Qg of the MOS)
- TDT = 250 ns
- TBLANK = 375 ns

The current control configuration should also be adjusted:
- TON_MIN = 3.5 us
- TOFF_MIN = 21 us
- TOFF_FAST = 10 us
- FAST_STEP = 16 us
- TSW = 48 us

Using this configuration you should obtain better results.

Question1: Predictive current control is working in step_mode ???
Yes, when it is enabled it is always active.
Question2: Is possible to modify tcc,tdt,tblank registers to get better torque at high revolution?
The high speed torque is usually limited by the supply voltage and the motor characteristics (higher the rotation speed, higher is difficulty to force the current into the motor phases). For the TCC, IGATE, etc. configuration see the previous point.  

BR
Enrico

嗨恩里科！
 
 
我测试了你的配置。但我在ON模式下的桥接参数是：
 
 ABS_POS = 0
 EL_POS = 0
 MARK = 0
 SPEED = 0
 ACC = 0x08A
 DEC = 0x08A
 MAX_SPEED = 0x041
 MIN_SPEED = 0
 FS_SPD = 0x027
 TVAL_HOLD = 0x50
 VAL_RUN = 2
 TVAL_ACC = 2
 TVAL_DEC = 2
 T_FAST = 0x48
 TON_MIN = 6
 TOFF_MIN = 0x29
 OCD_TH = 0x1F
 STEP_MODE = 0x0B
 ALARM_EN = 0xFF
 GATECFG1 = 0x0028
 GATECFG2 = 0x41
 CONFIG = 0xB000
 
如果尝试设置IGATE = 64mA，则桥接器永不打开。仅在4mA桥接器上打开。
在8mA时，电机试图移动，在一秒钟内，电桥关闭。
其他问题是OC_SD位。我的电路板仅在OC_SD = 0时工作。
尝试设置OCD_TH = 0x1F和TVAL_HOLD = 2但没有。
 
在IGATE = 4mA且OC_SD = 0的情况下，我的系统正常工作但是当我的电机试图移动时，它的声音移动非常糟糕。就像''干涉''。
附上视频!!!
 
关于oc_sd和Igate的一些想法？
最好的祝福，



以下为原文





Hi Enrico!!!


I have tested your configuration. but my parameters with bridge in ON mode are:

    ABS_POS = 0
    EL_POS = 0
    MARK = 0
    SPEED = 0
    ACC = 0x08A
    DEC = 0x08A
    MAX_SPEED = 0x041
    MIN_SPEED = 0
    FS_SPD = 0x027
    TVAL_HOLD = 0x50
    VAL_RUN = 2
    TVAL_ACC = 2
    TVAL_DEC = 2
    T_FAST = 0x48
    TON_MIN = 6
    TOFF_MIN = 0x29
    OCD_TH = 0x1F
    STEP_MODE = 0x0B
    ALARM_EN = 0xFF
    GATECFG1 = 0x0028
    GATECFG2 = 0x41
    CONFIG = 0xB000


if Try set IGATE = 64mA, bridge never turn on. Only in 4mA bridge is on.
In 8mA, motor try to move and in one sec, the bridge turn off.
Other problem is OC_SD bit. My board work only if OC_SD = 0.  
Try to set OCD_TH = 0x1F and TVAL_HOLD = 2 but nothing.

With IGATE = 4mA and OC_SD = 0, My system work but when my motor try to move, it move with sound really bad. is like ''interference''.
Attach video!!!

Some idea about oc_sd and Igate?
Best Regards,

这很奇怪。更高的栅极电流应该允许您在更短的时间内以更好的性能开启MOSFET。
 
 器件停止的事实是OC_SD很高（可能即使没有负载连接到功率级）也证实MOSFET未被正确驱动。
 
 请再试一次我的配置将VCC设置为15 V（我在上一篇文章中错过了这一点）并告诉我。



以下为原文





This is very strange. An higher gate current should allow you to turn-on the MOSFETs in shorter time and with better performance.

The fact that the device stops is OC_SD is high (probably even if no load is connected to the power stage) confirms that the MOSFETs are not properly driven.

Please, try again my configuration setting the VCC to 15 V (I missed this point in my previous post) and let me know.

亲爱的恩里科，
 
 
您的配置适用于15VCC。我真的很开心！！！谢谢
我需要你的帮助：
（1）在低速时，扭矩非常高且高速，扭矩减小，因为很难将力流送入相位电机。我在所有速度范围内都需要相同的扭矩。我的解决方案：我可以监控步进信号中的频率并修改tval_hold以尝试在我的所有速度范围内获得相同的扭矩。这是对的吗？或者我能以其他更好的方式获得相同的扭矩吗？
（2）当电机停止时...有时...我可以听到电机噪音。我的机器需要四个，五个或六个步进电机同时工作，不能接受太多的噪音。可以在电机停止时删除电机噪音吗？也许tsw注册其他值？
 
最好的祝福，
安德烈斯



以下为原文





Dear Enrico,


Your configuration is ok with 15VCC. Im really happy!!! Thanks
I need you help with this:  
(1) at low speed, torque is very high and high speed, torque decrease because is difficult force current into phases motor. I need same torque in all my range of speed. My solution: I can supervise frequency in step signal and modify tval_hold to try get same torque in all my range of speed. is it correct? or can I get same torque in other better way?
(2) when motor stop...sometimes...I can hear noise in the motor. My machines need four, five or six stepper motors working at same time and is not acceptable too much noise. Is possible delete noise in motor when it is stopped? maybe tsw register in other value?

Best Regards,
Andres

嗨，安德烈斯，
 
 
 
 （1）高速时的转矩限制与TVAL值无关。事实上，TVAL设定了您需要强制进入电机的目标电流（即扭矩）。
 如果导致BEMF无法对此目标值做出反应，则没有其他方法可以增加应用程序的电源电压。这样你就可以在高速时强制加大电流。
 （2）您可以降低调整当前控制参数的噪音。特别是你可以获得更低的噪音：
  - 减少TOFF_FAST值
  - 降低TSW值
 我建议您按照应用笔记AN4158了解有关当前控制算法的详细信息。
 
 亲切的问候
 恩里科



以下为原文





Hi Andres,



(1)The torque limit at high speed is not related to the TVAL value. In fact the TVAL set the target current (i.e. torque) which you need to force into the motor.
If cause the BEMF you cannot react this target value, there is no other way that increase the supply voltage of your application. This way you should be able to force higher current at high speed.
(2) You can reduce the noise adjusting the current control parameters. In particular you can obtain lower noise:
- Reducing the TOFF_FAST value
- Reducing the TSW value
I suggest you to follow the application note AN4158 for details about the current control algorithm.

Kind Regards
Enrico