Sensorless position control: Designing with ripple counting
Ripple Counting Demo Video
About
Many industrial applications use external sensors for position feedback and speed regulation of brushed DC motors which are often costly, complex, and take up valuable PCB space.
许多工业应用使用外部传感器对有刷直流电机进行位置反馈和速度调节，这些传感器通常成本高、结构复杂，而且占用宝贵的 PCB 空间。
In this video we introduce TI’s latest brushed DC motor technology, ripple counting; a sensorless approach to motor position and speed control. Eliminating encoders, hall effect sensors, optical sensors, shunt resistors and external sense resistors saves significant BOM cost and board space.
在本视频中，我们将介绍德州仪器最新的有刷直流电机技术--纹波计数；一种用于电机位置和速度控制的无传感器方法。无需编码器、霍尔效应传感器、光学传感器、分流电阻器和外部感应电阻器，从而节省了大量的 BOM 成本和电路板空间。
Transcript
What if you could control motor speed and position without any sensors? Position control is used in many industrial applications today. Printers, vacuum robots and other industrial applications use encoders, hall effect sensors and optical sensors to accomplish their goals. These external sensors can often be expensive, complex and take up valuable board real estate.
如果不用任何传感器就能控制电机速度和位置，会怎样？如今，位置控制在许多工业应用中都有使用。打印机、扫地机器人和其他工业应用都使用编码器、霍尔效应传感器和光学传感器来实现目标。这些外部传感器通常既昂贵又复杂，而且占用宝贵的电路板空间。
Texas instruments latest brush DC motor technology uses sensorless position and speed control, eliminating the need for these external sensors. Let's take a look at a DEMO that showcases this new technology.
德州仪器最新的有刷直流电机技术采用无传感器位置和速度控制，无需这些外部传感器。让我们看看展示这项新技术的演示。
Here you can see a modified roulette wheel driven by two separate motor drivers, one for the ball, and one for the wheel. The DEMO is designed to show the accuracy and repeatability of this new technology. We spin the digital knob to select the desired number, press the knob to go and the motor driver does the rest. After we press go, the wheel and ball spin and land on the selected number. The ball lands on any number we choose and does this all without sensors.
在这里，您可以看到一个改装过的轮盘，它由两个独立的电机驱动器驱动，一个用于小球，另一个用于轮盘。演示的目的是展示这项新技术的准确性和可重复性。我们旋转数字旋钮选择所需的数字，然后按下旋钮开始，剩下的工作就由电机驱动器完成。按下 “开始 ”键后，滚轮和小球旋转并落在所选的数字上。小球会落在我们选择的任何数字上，而这一切都无需传感器。
Our DRV8234 uses the motor's current waveform to track the motor's physical location. As you can see on the oscilloscope, a motor's current waveform has small distinct ripples caused by motor brushes making and breaking connections with the spinning commutator coils. Counting these ripples can provide the system closed loop feedback required to precisely control position of motor. For more information, check out the DRV8234 data sheet and APP brief on ti.com.
DRV8234 利用电机的电流波形来跟踪电机的物理位置。正如您在示波器上看到的那样，电机的电流波形具有明显的小波纹，这是由电机电刷与旋转的换向器线圈之间的连接和断开所引起的。对这些波纹进行计数可提供精确控制电机位置所需的系统闭环反馈。欲了解更多信息，请查看 ti.com 上的 DRV8234 数据表和 APP 简介。
DRV8234 data sheet, product information and support | TI.com
DRV8214 data sheet, product information and support | TI.com
View the DRV8234 datasheet
https://www.ti.com/lit/gpn/drv8234
Order the DRV8234EVM
DRV8234EVM Evaluation board | TI.com
参考：
Ripple Counting Demo Video | Video | TI.com
Ripple Counting Demo Video
