MotionDRV DC servo drive PID parameter tuning

lwsandy

MotionDRV DC servo drive PID parameter tuning [Copy link]

In the process of using servo drives, we all need to debug the drives. The most critical parameter debugging is PID parameter tuning. Many novices often lack experience in this area and don't know where to start. Here we introduce the basic debugging methods of PID parameters to help everyone quickly master the basics.
When it comes to servo, some drives on the market only have speed closed loop or position closed loop. Such drives are relatively simple and rough and cannot provide high-performance servo drive capabilities.
Professional drives will contain a complete three-loop system, including current closed loop, speed closed loop, and position closed loop. Here we will introduce the PID parameter tuning methods one by one starting from the current loop. Okay, let's go to the picture directly Current
closed loop debugging [attach] 554679 [/attach] 1. Set the Ki parameter to 0, and gradually increase the Kp parameter to ensure that the curve does not have the maximum Kp value of oscillation. After adjusting the Kp value, because Ki is 0, the curve will generally have a constant error, which we call steady-state error. In order to eliminate the error, we proceed to the next step of Ki parameter debugging.
2. Keep Kp unchanged and slowly increase Ki parameter until the actual current and the specified current curves are almost overlapped and no overshoot occurs.
As shown in Figure 1, the parameter adjustment of the current loop is completed. Isn't it very simple?
Speed closed loop debugging [attach] 554680 [/attach] The key parameter for debugging the speed closed loop is Kp. The Kp parameter determines the response speed and bandwidth of the speed loop. It is
still the same method
1. First increase the Kp parameter until the two curves are close to overlap and no oscillation occurs. This is the best.
2. Ki parameter, Ki parameter mainly eliminates steady-state error, this value can be adjusted roughly.
3. If a large tracking error occurs in the climbing stage of the curve, that is, the actual curve and the command curve differ greatly, it is necessary to increase the acceleration feedforward to reduce the tracking error.
Position closed loop debugging [attach] 554678 [/attach] Generally, for this loop, the speed feedforward can be kept at full speed feedforward and no further adjustment is required.
1. Adjust the Kp parameter, and adjust the Kp parameter repeatedly until the two curves almost completely overlap, there is no steady-state error, or there is only an error of a few pulses, and no steady-state oscillation occurs.
2. If a large following error occurs when the curve climbs. It is necessary to increase the acceleration feedforward, and it is necessary to debug repeatedly to get a satisfactory value.
At this point, the three closed loops have finally been fully debugged successfully!
Note: The debugging steps must be debugged one by one in the order of current closed loop -> speed closed loop -> position closed loop. The debugging of the latter loop is based on the previous loop. You cannot debug only one of the middle or last loops, otherwise you will not get the ideal effect.
We focus on the research and development and manufacturing of high-performance servo drives, and welcome to communicate!

freebsder

Is this picture a simulation or drawn based on real-time data feedback?

zshasd1948

Good article, I learned a lot, the content was well explained, I finally understood it, thumbs up, thank you for sharing!