In this article, you will learn how to determine the gain of a control system using different methods, such as open-loop transfer function, closed-loop transfer function, Bode plot, and Nyquist plot.

Loop gain plot of gain and phase margin of the open loop gain. (Image: Venable Instruments) The basic approach to determining the Bode plot is the same as using an oscilloscope: The transfer function ...

The Nyquist plot is a graphical technique that shows the mapping of the open-loop transfer function from the complex plane to the complex plane as the frequency varies from zero to infinity.

This, however, can only be done if we know the closed-loop transfer function. Usually though, the closed-loop transfer function is not known. In cases where the closed-loop transfer function is not ...

To perform the measurements, you inject a small AC signal into the power supply’s control-loop circuit and measure the loop’s gain and phase shift. By measuring the gain and phase, you can plot them ...

Figure 5 shows the bode plot of the complete loop gain frequency response. Figure 5 Bode plot is shown for the complete loop gain frequency response. Source: Monolithic Power Systems. Obtaining the ...

Fig. 1. Bode plot of a DC/DC converter. The phase margin of this converter is indicated as a very respectable 78 degrees and the gain margin, indicates a less than stellar, but acceptable 6.7 dB.

This study suggests a method to derive an approximate but sufficient formula of an open-loop transfer function for examining the oscillation seen for power devices connected in parallel. The stability ...