An output stabilization circuit includes: a primary-side circuit including first and second self-excited oscillator circuits connected to a direct-current power supply; and a secondary-side circuit, wherein the first and second self-excited oscillator circuits include power transmission coils, resonant capacitors, switching element pairs, and feedback coils, the second self-excited oscillator circuit further includes a phase shift filter, the phase shift filter includes a primary-side control coil that is magnetically coupled to a secondary-side control coil included in the secondary-side circuit and that has a characteristic that an inductance changes depending on a current flowing through the secondary-side control coil.

An output stabilization circuit includes: a primary-side circuit including first and second self-excited oscillator circuits connected to a direct-current power supply; and a secondary-side circuit, wherein the first and second self-excited oscillator circuits include power transmission coils, resonant capacitors, switching element pairs, and feedback coils, the second self-excited oscillator circuit further includes a phase shift filter, the phase shift filter includes a primary-side control coil that is magnetically coupled to a secondary-side control coil included in the secondary-side circuit and that has a characteristic that an inductance changes depending on a current flowing through the secondary-side control coil.

A power converter connected between a direct current power supply and a load, the power converter including a switching unit energizing the load based on inputted control signal, a voltage detector detecting a voltage of the direct current power supply, and a protection operation portion detecting a steep elevation of the voltage and performing protection operation to stop a switching operation by the switching unit, wherein the protection operation portion includes an addition circuit adding a predetermined voltage to the voltage detected by the voltage detector and a delay time generator connected to an output of the addition circuit, and wherein the protection operation is performed when a difference between the voltage detected by the voltage detector and an output voltage of the delay time generator reaches a certain value.

A power converter connected between a direct current power supply and a load, the power converter including a switching unit energizing the load based on inputted control signal, a voltage detector detecting a voltage of the direct current power supply, and a protection operation portion detecting a steep elevation of the voltage and performing protection operation to stop a switching operation by the switching unit, wherein the protection operation portion includes an addition circuit adding a predetermined voltage to the voltage detected by the voltage detector and a delay time generator connected to an output of the addition circuit, and wherein the protection operation is performed when a difference between the voltage detected by the voltage detector and an output voltage of the delay time generator reaches a certain value.

A switching power supply comprises one or more power supply stages configured to receive power from an input power source and to generate an output voltage for powering a load by alternately opening and closing a set of switches. An output current sensor is configured to monitor a level of an output current of the switching power supply. The opening and closing of the set of switches is controlled so as to maintain the output voltage at a desired level when the level of the output current is below the threshold and so as to limit the output current when the level of the output current exceeds the threshold.