Abstract: The present application relates to sensor systems for sensing mass concentration of particles smaller than a predetermined threshold in an air stream. Such systems may include an inlet (for receiving a total flow of air with particles) connected to a first splitter (for separating the total flow into a major flow and a minor flow), a joint where a first duct carrying the major flow and a second duct carrying the minor flow come together, and a sensor in the first duct for measuring the amount of particles smaller than the predetermined threshold in the major flow.

Abstract: The present application relates to sensor systems for sensing mass concentration of particles smaller than a predetermined threshold in an air stream. Such systems may include an inlet (for receiving a total flow of air with particles) connected to a first splitter (for separating the total flow into a major flow and a minor flow), a joint where a first duct carrying the major flow and a second duct carrying the minor flow come together, and a sensor in the first duct for measuring the amount of particles smaller than the predetermined threshold in the major flow.

Abstract: The present specification relates to an electric power converter, comprising at least a set of four controllable power switches, arranged in an H-bridge or a functionally equivalent circuit comprising two switching legs of two series switches connected to a voltage source, each power switch comprising an antiparallel diode, a controller configured for controlling the switches with a blanking time, a feedback loop for the load current, characterized by a first bias current injection circuit, coupled to the central point of the first leg of the H-bridge and a second bias current injection circuit, coupled to the central point of the second leg of the H-bridge. The specification further relates to a MRI scanner, provided with an electric power converter according to any of the preceding claims, for driving the gradient coils.

Abstract: A switched power converter unit has a DC voltage source with a positive output connection and a negative output connection; a series connection of two switching units; a first output clamp, coupled to a common point of the two switching units of a first parallel branch via a first inductive element; a diode arranged to allow current flow from the first output clamp to the DC voltage source; a diode arranged to allow current flow from the DC voltage source to the first output clamp; a capacitor coupled parallel to diode D1, and/or a capacitor coupled parallel to diode D2; a second output clamp, coupled to a common point of the two switching units of a second parallel branch via a second inductive element; a diode arranged to allow current flow from the second output clamp to the DC voltage source; a diode arranged to allow current flow from the DC voltage source to the second output clamp; a capacitor coupled parallel to diode D3, and/or a capacitor coupled parallel to diode D4.