US 12,259,713 B2
Automatic tuning of a proportional-integral-derivative controller for DC-DC buck switching power converter
Igor Boiko, Abu Dhabi (AE); Ahmed Shehada, Abu Dhabi (AE); Balanthi Mogru Abdul Rahiman Beig, Abu Dhabi (AE); and Yan Yan, Abu Dhabi (AE)
Assigned to Khalifa University of Science and Technology, Abu Dhabi (AE)
Appl. No. 18/010,087
Filed by Khalifa University of Science and Technology, Abu Dhabi (AE)
PCT Filed Jun. 29, 2021, PCT No. PCT/IB2021/055825
§ 371(c)(1), (2) Date Dec. 13, 2022,
PCT Pub. No. WO2022/003571, PCT Pub. Date Jan. 6, 2022.
Claims priority of provisional application 63/045,469, filed on Jun. 29, 2020.
Prior Publication US 2023/0266743 A1, Aug. 24, 2023
Int. Cl. G05B 19/4155 (2006.01)
CPC G05B 19/4155 (2013.01) [G05B 2219/42033 (2013.01)] 18 Claims
OG exemplary drawing
 
1. A method of automatically tuning a proportional-integral-derivative (PID) controller controlling a DC-DC buck switching power converter, comprising:
a) substituting the PID controller with a modified relay feedback test (MRFT) block having an MRFT magnitude (h) and a threshold parameter (β);
b) determining a current error signal (e[k]) by measuring an output voltage (Vo[k]) of the DC-DC buck switching power converter and comparing the output voltage (vo) to a desired reference output voltage (Vo-ref);
c) inputting the error signal (e[k]) to the MRFT block;
d) producing a MRFT block output signal u[k] in accordance with MRFT block equations, which can only be D+h or D−h, where D is a nominal duty-cycle, and updating the nominal duty cycle (D) to the value given by the controller output signal u[k];
e) operating the DC-DC buck switching power converter using the updated nominal duty cycle (D);
f) repeating steps from b) through e), which results in generation of self-excited oscillations due to the switching of the MRFT block output between the values D+h and D−h, until a predefined number of cycles (Ncycles) is observed;
g) measuring a frequency (Ω0) and amplitude (a0) of oscillations of the output voltage (Vo[k]) of the DC-DC buck switching power converter;
h) updating PID controller parameters based on the frequency (Ω0) and amplitude (a0) of the oscillations of the voltage output (Vo[k]) of the DC-DC buck switching power converter; and
i) substituting the MRFT block with the PID controller.