Abstract: A control circuit and a method for controlling a control circuit are described. The control circuit is connected to at least two electrical loads connected in parallel. An electric melting metal fuse is connected in series with each electrical load. The method comprises: monitoring the total current provided to the electrical loads and in case the total current from the control circuit during normal operation exceeds a nominal preset current limit, providing one of: a first electric pulse to the loads during a preset first time period at a current which is higher than the nominal preset current limit, and a second electric pulse to the loads during a preset second time period.

Abstract: To expand the power output capacity of a power plant comprising a first and a second rectifier connected in parallel to a varying load, the output voltage of the first rectifier being essentially constant within its load current operating range, said second rectifier is controlled to supply, at said first rectifier output voltage (U1), a constant load current (0.8×I3max) that is lower than its maximum current (I3max) to shift the operating range of said first rectifier correspondingly to higher current values. Said second rectifier is controlled to supply, at a predetermined lower output (U3″) voltage, load currents between said constant load current (0.8×I3max) and said maximum current (I3max) in response to maximum current (I1max) from said first rectifier. In response to load currents that are lower than said constant load current (0.8×I3max), the output voltage is limited to a predetermined higher voltage (U3′).

Abstract: A full float system with Transient Free Multiple Load Disconnection Reconnection (TFMLDR) is disclosed. The system is based on a concept of always connecting loads and dedicated rectifiers together, and then connect such groups (1-n) via power switching devices (C1-Cn) to a pair of busbars. A backup battery is typically connected directly to the busbars via a respective fuse (F114 Fy). The disconnection/reconnection of individual groups to a busbar can then be controlled such that no transients are produced in the system voltage. Such a system is advantageous for reconnection of a load after a disconnection due to a mains power failure. The loads present a substantial input capacitance assisting in stabilizing DC power supply to the load and this load is directly connected to a rectifying unit delivering voltage controlled power during normal mains power operation. After a disconnection of a load from the busbar and the battery by the power switching member, a reconnection will be done in the following order.

Abstract: A method and an arrangement of in-circuit capacity testing of at least one stand-by electrical energy storage device (1; 11; 12) connected between two conductors (3, 4; 13, 14) in parallel with a DC supply, in turn supplied from a mains line, and also in parallel with a power consuming device (2) is described. A controllable current source (6) is provided that is connectable in series with the battery (1). A control device (7) controls the controllable current source (6) to maintain either a desired output current or a desired output power from the battery (1). A voltage measuring device (8) for measures the voltage across the battery (1) to determine its capacity at least during testing.

Abstract: A full float system with Transient Free Multiple Load Disconnection Reconnection (TFMLDR) is disclosed. The system is based on a concept of always connecting loads and dedicated rectifiers together, and then connect such groups (1-n) via power switching devices (C1-Cn) to a pair of busbars. A backup battery is typically connected directly to the busbars via a respective fuse (F1-Fy). The disconnection/reconnection of individual groups to a busbar can then be controlled such that no transients are produced in the system voltage. Such a system is advantageous for reconnection of a load after a disconnection due to a mains power failure. The loads present a substantial input capacitance assisting in stabilizing DC power supply to the load and this load is directly connected to a rectifying unit delivering voltage controlled power during normal mains power operation. After a disconnection of a load from the busbar and the battery by the power switching member, a reconnection will be done in the following order.

Abstract: In a rectifier bridge, a method and system for starting a DC-driven device without the occurrence of a current surge. The input of the rectifier bridge is connected to a three-phase source and a storage capacitor is connected across the output of the rectifier bridge. At least two of the three input terminals of the rectifier bridge are each connected in series to a respective AC capacitor. Each of the capacitors is connected in parallel with a respective controlled switch which functions to short-circuit the capcitors subsequent to the storage capacitor being charged.