SLUAAX1 July 2024 UCC24624

4 Simulation Verification

To verify the accuracy of the calculation results, Table 4-1 shows three sets of parameters in the simulation to observe the actual length of time, as shown in Figure 4-1, Figure 4-2, and Figure 4-3.

Table 4-1 Parameters Under Different Conditions

V_in	400V	400V	400V
V_o	40V	42V	40V
f_s / f_r	212khz/170khz	235khz/170khz	265khz/170khz
L_r / L_m	10uH/56uH	10uH/56uH	10uH/56uH
$α_{1}$ (simulated/calculated)	2.22e-7/2.25e-7s	7.76e-8s/7.79e-8s	9.77e-8s/9.81e-8s

UCC24624 PMP41042 The Waveform of the First Set
of Parameters

Figure 4-1 The Waveform of the First Set of Parameters

UCC24624 PMP41042 The Waveform of the Second Set
of Parameters

Figure 4-2 The Waveform of the Second Set of Parameters

UCC24624 PMP41042 The Waveform of the Third Set
of Parameters

Figure 4-3 The Waveform of the Third Set of Parameters

The calculations from the simulation result are relatively accurate, meaning you can set up a delay based on these calculated results.

If the dead time is set to 100ns, then set a delay for the SR start-up time when α₁ is greater than 100ns, where delay time is α₁ minus the dead time. Figure 4-4 shows time curves α₁ for different output voltages and loads, which shows that the worst case occurs in the case of the lowest output voltage, the heaviest load.

UCC24624 PMP41042 Time Curves For Different
Output Voltages and Frequency

Figure 4-4 Time Curves For Different Output Voltages and Frequency