If the post$-$compensation crossover frequency $f_c=\frac{{}_c}{2}=1\mathrm{.}6kHz,$ the transfer function given in Eq$.(4)$ will require a Type $3$ compensator to adjust the crossover frequency to the specified value, to provide adequate low$-$frequency gain, and to set phase margin at $40.$ A Type $3$ compensator is shown in Eq$.(5).$

$\frac{u(s)}{v_{\text{e}\text{r}\text{r}\text{o}\text{r}}(s)}=K_{PWM}\frac{{}_{\text{I}}}{s}\frac{(s+{}_{z1})(s+{}_{z2})}{(s+{}_{p1})(s+{}_{p2})}$

Design a Type $3$ Compensator for this transfer function following Venable's Method $($i$.$e$.,$ the $k-$factor method of separating the compensator's poles and zeros about the geometric mean frequency$)$ described as Procedure I in "Type III Compensator Design for Power Converters" by Liyu Cao $[$published in Power Electronics Technology, January $2011].$

By design it is meant:

$,$ Select the gain $K_{PWM}^{**}{}_{\text{I}},$

Select the zero frequency ${}_z($assuming that ${}_z={}_{zl}={}_{z2})$

Select the pole frequency ${}_p($assuming that $($:${}_p={}_{p1}={}_{p2}$