Abstract: A power supply is described, which comprises a first stage DC-to-DC voltage conversion block and a second stage voltage conversion block having a feedback circuit to regulate the output voltage (Vout) thereof so as to reduce changes in the output voltage as the output current (Iout) drawn by a load changes. The power supply also includes a capacitor connected between the first and second stage voltage conversion blocks to supply current to the second stage voltage conversion block when the input voltage (Vint) to the second stage voltage conversion block changes due to changes in output current (Iout) of the second stage voltage conversion block. The first stage voltage conversion block comprises a feedback circuit to regulate the output voltage of the first stage voltage conversion block.

Abstract: A protection switching system in a power supply distribution system, comprises at least one protection switch (25) comprising a controllable semiconductor arranged to conduct current through the power supply line in a normal mode, a control unit (27) arranged to place the at least one protection switch in a test mode in which the current is reduced compared to the normal mode, registration means (28, 29) for registering a test mode value of at least one electrical characteristic in the power supply line that will be affected when the test mode is applied, a monitoring unit (30; 47) arranged to evaluate the at least one electrical characteristic and determine, based on the evaluation, whether or not an action should be taken. If a malfunction is detected an alarm is issued to indicate to service personnel that the protection switch should be replaced.

Abstract: A power supply is described, which comprises a first stage DC-to-DC voltage conversion block, and a second stage voltage conversion block having a feedback circuit to regulate the output voltage (Vout) thereof so as to reduce changes in the output voltage as the output current (Iout) drawn by a load changes. The power supply also includes a capacitor connected between the first and second stage voltage conversion blocks to supply current to the second stage voltage conversion block when the input voltage (Vint) to the second stage voltage conversion block changes due to changes in output current (Iout) of the second stage voltage conversion block. The first stage voltage conversion block comprises a feedback circuit to regulate the output voltage of the first stage voltage conversion block.

Abstract: A protection switching system in a power supply distribution system, comprises at least one protection switch (25) comprising a controllable semiconductor arranged to conduct current through the power supply line in a normal mode, a control unit (27) arranged to place the at least one protection switch in a test mode in which the current is reduced compared to the normal mode, registration means (28, 29) for registering a test mode value of at least one electrical characteristic in the power supply line that will be affected when the test mode is applied, a monitoring unit (30; 47) arranged to evaluate the at least one electrical characteristic and determine, based on the evaluation, whether or not an action should be taken. If a malfunction is detected an alarm is issued to indicate to service personnel that the protection switch should be replaced.