Abstract: An electrical assembly includes a number of modules, each module including at least one module switching element and at least one energy storage device, each module switching element and each energy storage device in each module arranged to be combinable to provide a voltage source, each module including a discharge circuit with a discharge switching element and a discharge resistor, each discharge switching element switchable to switch the corresponding discharge resistor into and out of the corresponding module, wherein the electrical assembly includes a controller configured to control the discharge switching elements to modulate the switching of each discharge resistor into and out of the corresponding module in a voltage balancing mode when the modules are in a blocked state so that each module emulates a resistive load profile to balance a distribution of voltages between the modules, wherein the resistive load profile includes at least one positive resistive slope.

Abstract: An electrical assembly includes a number of modules, each module including at least one module switching element and at least one energy storage device, each module switching element and each energy storage device in each module arranged to be combinable to provide a voltage source, each module including a discharge circuit with a discharge switching element and a discharge resistor, each discharge switching element switchable to switch the corresponding discharge resistor into and out of the corresponding module, wherein the electrical assembly includes a controller configured to control the discharge switching elements to modulate the switching of each discharge resistor into and out of the corresponding module in a voltage balancing mode when the modules are in a blocked state so that each module emulates a resistive load profile to balance a distribution of voltages between the modules, wherein the resistive load profile includes at least one positive resistive slope.

Abstract: AC calibration apparatus (2) comprising an analogue to digital converter (4), and in which the absolute gain of the analogue to digital converter (4) is dynamically assessed by applying a reference AC signal which is in addition to a sampling signal required for measurement purposes and which is a square wave of a known amplitude at a precise sub-harmonic of the sampling frequency of the analogue to digital converter (4).