An induction cooktop that includes a first main switch and a second main switch configured to be operated by a control unit to selectively connect a first induction heater and a second induction heater, to a switching converter for selectively energizing the first induction heater and/or the second induction heater; wherein the control unit is configured (i) to sense an electric parameter regarding the first induction heater in a first resonant circuit, when the first induction heater is not fed from the switching converter and a first auxiliary switch closes the first resonant circuit in such a way that the at least resonant capacitor assembly is connected to the first induction heater by means of the first auxiliary switch and a damped oscillation occurs between them; (ii) to sense an electric parameter regarding the second induction heater in a second resonant circuit when the second induction heater is not fed from the switching converter and the second auxiliary switch closes the second resonant circuit in such a way that the at least resonant capacitor assembly is connected to the second induction heater by means of the second auxiliary switch and a damped oscillation occurs between them; and (iii) to detect the presence of a pan on the cooktop on the basis of the sensed electric parameter.

In a method for a cooktop, in particular for producing and/or operating the cooktop, which has at least one variable cooking surface, the cooking surface is partitioned in an operating mode along a partitioning direction into a plurality of heating zones to which at least one heating parameter is assigned in each case in a location-dependent manner in order to heat a cooking utensil that is deposited on the heating zone. In order to ensure flexible production and/or flexible operation of the cooktop, during partitioning of the cooking surface into the heating zones in at least one peripheral region of the cooking surface, at least one cooking utensil characteristic is taken into account.

A heating device includes a resonant circuit, a detection unit and a control unit. The resonant circuit includes an inverter circuit and a resonant tank. The inverter circuit provides a resonant tank current and a resonant tank voltage. The resonant tank includes a heating coil, a resonant tank capacitor, a resonant tank equivalent inductor and a resonant tank equivalent impedance. The detection unit detects the resonant tank current and the resonant tank voltage to acquire associated parameters. The detection unit calculates an inductance of the resonant tank equivalent inductor according to a capacitance of the resonant tank capacitor, a resonant period and a first expression. The detection unit calculates an impedance value of the resonant tank equivalent impedance according to the inductance of the resonant tank equivalent inductor, a time difference, the resonant period, a reference current value, a negative peak current value and a second expression.

An induction heating device according to an embodiment includes a rectifying circuit configured to rectify an AC voltage supplied from a power supply, a smoothing circuit configured to smooth a voltage output from the rectifying circuit, an inverter comprising a plurality of switches and configured to supply current to a working coil, a shunt resistor coupled between the smoothing circuit and the inverter, a drive circuit configured to supply switching signals to the plurality of switches provided in the inverter, respectively, and a controller configured to determine a driving frequency of the inverter and drive the working coil by supplying a control signal based on the driving frequency to the driving circuit.

An induction heating device of one embodiment includes a working coil, an inverter including a first switch and a second switch and supplying a resonance current to the working coil, a phase sensing circuit outputting a pulse signal that indicates a phase difference between the resonance current and a switching voltage of the second switch, and a controller calculating a final phase difference between the resonance current and the switching voltage of the second switch, based on the pulse signal, and adjusting an output power value of the working coil, based on the final phase difference.

An induction heating device according to an embodiment includes an inverter configured to supply an AC current to a working coil and includes a plurality of switches; a drive circuit configured to supply a switching signal for a switching operation of the plurality of switches to the inverter; and a controller configured to control driving of the working coil by supplying a control signal corresponding to a required power value of the working coil to the drive circuit. The controller may drive the working coil based on the required power value, receive a resonance current value of the working coil when the working coil is driven, calculate a container efficiency index based on an output power value of the working coil, the required power value, the resonance current value and a preset limit current value, and control the driving of the working coil based on the container efficiency index.

Disclosed apparatus and methods make it convenient for small portions of lasagna to be prepared conveniently and quickly. A cooking vessel and its top re described. The internal chamber of the cookware is rectangular, and its internal sidewalls are vertical. Length of the chamber is selected to accommodate layers of lasagna including a single piece of pasta. A foil container is inserted into the chamber, in which the lasagna layers are constructed, and the lasagna is cooked within the vessel and its insert. Walls of the cookware are made of ferromagnetic material such as cast iron and have a thickness that is capable of holding a significant amount of heat, which is transferred conductively to the lasagna during cooking, including pressure cooking. An induction cooking device is disclosed that does not require the cookware to be heated in a conventional oven. The device functions conjointly with the cookware.

In order to detect on an induction cooktop whether a cooking vessel with an integrated controller or smart functionality is arranged over an induction heating coil, the induction heating coils emit a short individual code. The latter can be detected and evaluated by the cooking vessel such that the cooking vessel emits a signal corresponding to this code which is received by an external operating means or the induction cooktop to locally associate this cooking vessel with this induction heating coil. Transmission or transfer of energy as a code proceeds at a frequency of at least 50 kHz, wherein a code has a plurality of pulse sequences, each of which has at least two pulses.

An induction energy transmission system includes a supply unit having a supply induction element to inductively provide energy in an operating state. A receiving unit receives at least part of the energy provided by the supply induction element in the operating state. A sensor unit detects a measurement variable and a first information channel transmits a first signal between the receiving unit and the supply unit, with the first signal coding the measurement variable. A second information channel which differs from the first information channel transmits a second signal between the receiving unit and the supply unit, with the second signal coding the measurement variable.

A DC powered cooking appliance which uses an induction or a resistance based DC heating element and excludes AC powered heating elements and preferably does not rely on directly connected combustion powered heating elements. Some embodiments include wattage of 1500 watts or less, voltages of 40 or 48 volts or more and are installed on a boat, van, rv or bus such that an inverter of that boat, van, rv or bus is not electrically connected to the cooking appliance.