A power supply topology operating at highly discontinuous input voltages for two-wire connected control devices in Digital Load-Side Transmission (DLT) systems for intelligent lighting

Abstract

This paper presents a power supply concept for control devices in Digital Load-Side Transmission (DLT) systems delivering a high energy output. The proposed topology consists of two stages, a boost converter and a flyback converter. As a direct replacement for conventional light switches or dimmers, this power supply works without a neutral wire connection and is supplied with energy compliant to the DLT specification [1] through a switched bypass structure in the series connected DLT luminaire. This method enables the application of DLT systems in existing installations, which typically lack a neutral wire at the light switch lead-out. Although operating at a highly discontinuous and varying input voltage, the proposed two-stage topology provides a continuous high output power of maximum P out,max = 475 mW. Input voltages of up to 100 V can be handled. The output voltage is regulated to 3.3 V, a typical value to supply microcontrollers with attached periphery, e.g. common WiFi modules [2], [3]. It is shown that the measured output power is high enough to operate a WiFi frontend. Completely new functionality, such as integrating a DLT control device into a smart home infrastructure, is hence realized.