A DC POWER SOURCE FOR A HIGH VOLTAGE POWER APPARATUS

摘要

The invention relates to a dc power source (3) for a high voltage power apparatus (1), the dc power source (3) comprising one or more strings (4a-c) including a plurality of dc power source units connected in series, and switches (7, 9, 11, 13) configured to connect and disconnect said strings (4a-c). The switches (7, 9, 11, 13) are solid-state switches distributed among the power source units of each string (4a-c), and all solid-state switches (7, 9, 11, 13) in the string (4a-c) are arranged so that they are turned on and off simultaneously. Each switch (7, 9, 11, 13) is connected in parallel with a first controllable semiconductor (16) in a first direction and connected in parallel with a second controllable semiconductor (20) in a second direction which is opposite to the first direction, and the dc power source (3) comprises a control unit (21) configured to bypass a failed switch (7, 9, 11, 13) by triggering the forward biased of the first (16) or second (20) controllable semiconductor connected to the failed switch (7, 9, 11, 13) in case a fault in the switch (7, 9, 11, 13) is detected