Haier US Appliance Solutions, Inc.

Isaac Nam

William Hull Bicknell

Meher Prasadu Kollipara

Victoria Steele

Induction cooktops and operational methods are provided herein. A method of determining presence of compatible cookware on an induction cooktop can include receiving a request to heat the induction cooktop, controlling at least one switching device to induce a current within an assumed piece of cookware with an induction coil of the induction cooktop, sensing a voltage associated with the at least one switching device, the voltage being proportional to current flowing in the induction coil, determining that the sensed voltage includes one or more voltage spikes above a first threshold, and determining that the assumed piece of cookware is absent when the sensed voltage includes the one or more voltage spikes.

Determining presence of compatible cookware in induction heating systems

An induction cooking appliance is provided herein. The induction cooking appliance may include an upper cooking surface, a power source, and a heating assembly in electrical communication with the power source. The power source may be configured to supply a power signal during heating operations. The heating assembly may include a first induction heating coil and a second induction heating coil. The first induction heating coil may be positioned below the upper cooking surface in electrical communication with the power source. The second induction heating coil may be positioned coaxial with the first induction heating coil below the upper cooking surface. The second induction heating coil may be disposed in electrical communication with the power source in non-series communication with the first induction heating coil.

Induction cooking appliance having multiple heating coils

Systems and methods of quasi-resonant induction heating are provided. In particular, a method for evaluating the resonant frequency of a quasi-resonant induction cooking device can be provided. The method can include generating a startup pulse, receiving multiple feedback pulses from a resonant frequency feedback circuit, measuring a pulse width of each of the feedback pulses, calculating an average pulse width based upon the feedback pulses and determining the resonant frequency based at least in part on the average pulse width and a transfer function.

Determining resonant frequency for quasi-resonant induction cooking devices

An induction heating system with a plurality of resonant inverter tanks can be provided. The induction heating system can include a power source configured to supply power to the heating system and a plurality of parallel resonant inverter tanks in electrical connection with the power source. Each of the parallel resonant inverter tanks can include one or more parallel resonant capacitors, one or more parallel induction coils and one or more switches configured to disconnect each of the parallel resonant inverter tanks from the power source. The induction heating system can include a controller configured to perform operations, wherein the operations include determining when a cooking vessel is present at each induction coil and in response to determining that a cooking vessel is not present at a resonant inverter tank, operating the one or more switches such that the parallel resonant inverter tank is disconnected from the power source.

Co-axial multi-zone induction cooking apparatus

Systems and methods for providing self-driven active AC rectification are provided. In particular, a power conversion system for providing self-driven active AC rectification can be provided. The system can include an input for receiving AC power, a first capacitor and a second capacitor electrically connected in series. The first and second capacitors can also be electrically connected in parallel with a rectifier's load. The system can include a low-side switching element and a shunt resistor electrically connected between the rectifier's load and a system ground. The power conversion system can also include a low-side feedback control loop configured to obtain a low-side feedback signal based on a voltage across the shunt resistor and the low-side feedback control loop can be further configured to control the low-side switching element based, at least in part, on the low-side feedback signal.

Growing community of inventors

Louisville, KY, United States of America

Isaac Nam