PID parameters significance mentioned in User guide and how to calculate them ? I am using MagniV development board for for BLDC control .... I have also took reference from NXP code for speed and current loop control with PI control ..... for PI control loop parameters calculations are done using freemaster tool....Is there any such tool for PID loop parameter calculation ? Also please define significance of PID parameters used in NXP PID function mentioned in user guide that came with code . Re: PID parameters significance mentioned in User guide and how to calculate them ? for another process: 1. motor 95W, 12V, the R is about: 1.2ohm, and L is about:2.5mH 2. it suggest the switch freq is 160Hz, which is 1000 rad/s( 1000/3.1416/2=160Hz) 3. and it suggest the Z_final is 1. so: s = 1/(R+2*pi*L*freq) = 1/(1.2+2*3.14156*2.5e-3*160) = 1/(1.2+2.5) here is a jump: 1.Kp = 2*3.1416*2.5e-3*160-R = 5-1.2 = 3.8 2.Ki = w^2*L = 2500 3.because the Vol, curr is standlize, so :Kp = 3.8 * 8/12 = 3.8*0.667=2.5 at this stage, AI said the L maybe wrong. ---------------- let me try to calc the right motor params. if engine is cos(theta)=0.85 >>> import numpy as np >>> np.acos(0.85) np.float64(0.5548110329800715) >>> np.sin(0.555) np.float64(0.5269433002033014) then sin(theta)=0.5. so: when engine at std power out. the Curr_R and Curr_L is equal. so:R = 12*0.707/(8*0.707) = 1.5ohm, this is right. L：9000rpm is 150Hz,so, I think the error is bandwith, it should be higher than 1500Hz, and maybe 3000Hz if freq_std=1500, which means the L should be 12*0.85/(2*pi*1.5e3) = 10mH ~5mH so：Ki = 14e3*10e-3 = 140 or 70. Kp = 2*pi*1.5e3*L -R = 94-1.5 = ... still wrong.... Re: PID parameters significance mentioned in User guide and how to calculate them ? hi,there. I am a naive to pid ctrl. this is the first post I found. here are some my foundings in this forum and knowledge. S32K344 - FOC integrated with FreeRTOS this is the beginning line. After I install the EV boards, I got the PMSM_appconfig.h, the pid params, init params is : #define CLOOP_D_KP (0.368399F) #define CLOOP_D_KI (0.0298853F) #define CLOOP_Q_KP (0.371817F) #define CLOOP_Q_KI (0.0298853F) this is FOC controler, so there are two PI params here. so the Kp is the most important one. so,here is my calc: the PID(err_of_vol) = Curr. Vol range is 12V the motor power is 95W, so the output Curr is :95/12=8A. so： Kp = 8/12 = 0.67... but the motor can support forword and backword rolling, so the Vol must split into 2Parts. so : if you using +12V to support all roll on roll back, kp should be 8*2/12=1.33 if you using something like revert the DC+ DC-, it should be just 0.67. if you tune it, it always start an a more small value. for example 20% of it. so at last, the 0.37 is more larger than 20%*1.33= 0.27 Ki is about 10percent of Kp, here is Ki = 1/12*Kp but it seems it is totally wrong. I heard sth about Qianwen(An AI-Chat) 1. NXP should Standlize the Curr & Vol, for the very first stage. 2.what the calc is based Zero,and Polor Point of Control Space. I will try to figure it out later, it said, the motor's PID params will first try to measure motors' L,R then calc. Re: PID parameters significance mentioned in User guide and how to calculate them ? Hello, We use PI controllers in the structures of our motor control examples on the web. As you write, Mcat helps with the calculation of parameters for the PI controllers used (for PMSM in the cascade control structure for BLDC in the structure for sixstep). At the moment we do not have an example on the web that would use a structure with a PID controller or a tool that would help to set it, but of course, our AMCLIB library also offers this function as a building block for customer control structures. I hope it helps. Best regards, Diana
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