Power Supply Device and Luminaire

A luminaire comprising:

• a power supply device;
• and
• a lighting load functioning as a load circuit of the power supply device,
• the power supply device including
• a first inductor,
• a current control section configured to limit a current value of an electric current flowing through the first inductor to a predetermined current value, the current control section including a first switching element of a normally on type and a resistor connected to a main terminal of the first switching element,
• a rectifying element connected to the current control section in series, an electric current flowing to the rectifying element when the current control section is off, and
• a second inductor magnetically coupled to the first inductor and configured to induce a voltage for turning on the current control section, when the electric current of the first inductor increases, to induce a voltage for turning off the current control section, when the electric current of the first inductor decreases, and to supply the induced voltage to a control terminal of the current control section.