To realize the buck/Improve element, all of that is necessary is 2 separate switches so the AC input is usually connected to one of many two Major faucets, although the load is linked to the opposite, thus utilizing the key transformer's primary windings as an autotransformer. Illustration #7 - you https://historyofjudo16048.full-design.com/ups-uninterruptible-power-supply-things-to-know-before-you-buy-76203306