CONVERTER CIRCUIT, AND MOTOR DRIVE CONTROLLER EQUIPPED WITH CONVERTER CIRCUIT, AIR CONDITIONER, REFRIGERATOR, AND INDUCTION COOKING HEATER

摘要

To obtain a converter circuit capable of being made to be small and light-weighted and reducing switching loss, a motor drive control apparatus, an air-conditioner, a refrigerator, and an induction heating cooker provided with the circuit. There are provided: a step-up converter 3a including a rectifier 2, a step-up reactor 4a, a switching element 5a, and a reverse current prevention element 6a; a step-up converter 3b having a step-up reactor 4b, a switching element 5b, and a reverse current prevention element 6b and connected in parallel with the step-up converter 3a; switching control means 7 that controls switching elements 5a and 5b; and a smoothing capacitor that is provided at the output of the step-up converters 3a and 3b. The switching control means 7 switches the current mode of the current flowing through the step-up reactors 4a and 4b into any of a continuous mode, a critical mode, and a discontinuous mode based on a predetermined condition.