A voltage conversion device configured to convert an input alternating voltage into a direct voltage or current, the voltage conversion device including at least a first voltage connector and a second voltage connector, both configured to to be connected to the alternating voltage, the voltage conversion device further including: an electromagnetic filter unit configured to electromagnetically filter the alternating voltage, which is input to either the first voltage connector or the second voltage connector; a conversion unit configured to convert the voltage which has been electromagnetically filtered by the electromagnetic filter unit into a direct voltage or current and output the same; a determination unit configured to determine to which one of the first voltage connector and the second voltage connector the alternating voltage is connected to; and a control unit configured to control the conversion unit based on a determination result of the determination unit such that the direct voltage or current output by the conversion unit corresponds to the determination result, wherein the determination unit is electrically connected to the first voltage connector and the second voltage connector, characterized in that the determination unit includes a first switch element and a second switch element, the determination unit further includes a first diode and a second diode, wherein the first diode and the second diode are connected in anti parallel between the first voltage connector and the second voltage connector, wherein the first diode is arranged to turn on in a certain half cycle of the alternating voltage and to turn on the first switch element only in said half cycle of the alternating voltage, and wherein the second diode is arranged to turn on and cut off the first switch element in another half cycle of the alternating voltage, and that the determination unit is configured so that - when the alternating voltage is fed to the voltage conversion device via the first voltage connector, both of the first switch element and the second switch element are turned off; and - when the alternating voltage is fed to the voltage conversion device via the second voltage connector, the first switch element is periodically turned on as a result of conduction of the first diode only in said half cycle of the alternating voltage, causing the second switch element to be turned on during a full cycle, i.e. during said half cycle and said another half cycle, of the alternating voltage, thereby continuously indicating to the control unit the connection of the alternating voltage to the second voltage connector. an electromagnetic filter unit configured to electromagnetically filter the alternating voltage, which is input to either the first voltage connector or the second voltage connector; a conversion unit configured to convert the voltage which has been electromagnetically filtered by the electromagnetic filter unit into a direct voltage or current and output the same; a determination unit configured to determine to which one of the first voltage connector and the second voltage connector the alternating voltage is connected to; and a control unit configured to control the conversion unit based on a determination result of the determination unit such that the direct voltage or current output by the conversion unit corresponds to the determination result, wherein the determination unit is electrically connected to the first voltage connector and the second voltage connector, characterized in that the determination unit includes a first switch element and a second switch element, the determination unit further includes a first diode and a second diode, wherein the first diode and the second diode are connected in anti parallel between the first voltage connector and the second voltage connector, wherein the first diode is arranged to turn on in a certain half cycle of the alternating voltage and to turn on the first switch element only in said half cycle of the alternating voltage, and wherein the second diode is arranged to turn on and cut off the first switch element in another half cycle of the alternating voltage, and that the determination unit is configured so that - when the alternating voltage is fed to the voltage conversion device via the first voltage connector, both of the first switch element and the second switch element are turned off; and - when the alternating voltage is fed to the voltage conversion device via the second voltage connector, the first switch element is periodically turned on as a result of conduction of the first diode only in said half cycle of the alternating voltage, causing the second switch element to be turned on during a full cycle, i.e. during said half cycle and said another half cycle, of the alternating voltage, thereby continuously indicating to the control unit the connection of the alternating voltage to the second voltage connector. - when the alternating voltage is fed to the voltage conversion device via the first voltage connector, both of the first switch element and the second switch element are turned off; and - when the alternating voltage is fed to the voltage conversion device via the second voltage connector, the first switch element is periodically turned on as a result of conduction of the first diode only in said half cycle of the alternating voltage, causing the second switch element to be turned on during a full cycle, i.e. during said half cycle and said another half cycle, of the alternating voltage, thereby continuously indicating to the control unit the connection of the alternating voltage to the second voltage connector.