Abstract: Modular power systems, smart battery modules, and monitoring and control systems are described herein. The modular power system comprises at least one mains converter connected between a mains supply and a DC bus, a monitoring and control system connected to the DC bus, and a plurality of smart battery modules configured to be removably connected in parallel to the DC bus. Each battery module comprises a decoupling unit configured to electrically disconnect, or connect the battery module to, or from, the DC bus. The monitoring and control system is configured to monitor supply of mains power to the mains converter, the voltage of the DC bus, the terminal voltage of each smart battery module, and the magnitude of the load is that is present on the DC bus. The monitoring and control system is configured to control the DC output voltage of the mains converter; and control the decoupling unit of each smart battery module to be in one of at least: a connected mode, and a disconnected mode.

Abstract: A load balancing apparatus for balancing the current supplied on each phase of a multiple phase supply, Each supply phase feeds an AC load, as well as an AC-DC converter. The apparatus measures the current supplied from each phase of the supply as well as the power consumed by each of the AC loads. The power consumed by each of the AC-DC converters is adjusted so that the sum of the current drawn by any one of the AC loads, plus the current drawn by the AC-DC converter on the same supply phase, is substantially balanced between the supply phases. Typically the AC-DC converters supply a common DC battery. In some embodiments each AC load includes a DC-AC converter configured to supply power from the common DC battery to one or more of the AC loads.