US Patent 11190015 Control of heating elements

An apparatus for controlling one or more switched high power loads (or heating elements). The apparatus including: one or more switched high power loads (or heating elements), each high power load being powered from a common alternating current power source, and wherein each load is independently switched using a switching signal for zero crossing switching to achieve a desired average power output; the switching signal is generated that comprises a repeated switching sequence; the switching sequence indicates a respective selecting activation for each of the switched high power load over a sequence of half or full cycles.