Induction hob device, induction hob and method for operating an induction hob device

Abstract

The invention is based on an induction hob device (10a-10d) comprising at least one step-up converter unit (12a-12d), the step-up converter unit (12a-12d) having at least one emission induction unit (14a-14d). In order to reduce the number of components, the invention proposes that the emission induction unit (14a-14d) is intended to function as a boost inductance unit (16a-16d).

Description

[0001] Induction hob device, induction hob and method for operating an induction hob device

[0002] The invention relates to an induction hob device according to the preamble of claim 1, an induction hob according to claim 11 and a method for operating an induction hob device according to claim 12.

[0003] Induction cooktops with a boost converter unit are known from the prior art, wherein a boost coil of the boost converter unit is designed separately from a heating coil, which is provided for emitting inductive energy to heat a cooking utensil. Such induction cooktops are known from WO 2016071803 A1 and WO 2016071824 A1, but the topologies disclosed therein are not economically feasible due to the high number of components.

[0004] The object of the invention is, in particular but not limited to, to provide a generic device with improved properties in terms of a reduced number of components. This object is achieved according to the invention by the features of claim 1, while advantageous embodiments and further developments of the invention can be found in the subclaims.

[0005] The invention is based on an induction hob device with at least one boost converter unit, wherein the boost converter unit has at least one emission induction unit.

[0006] It is proposed that the emission induction unit is intended to act as a boost inductance unit.

[0007] Such a configuration advantageously makes it possible to achieve an induction hob device with a reduced number of components, in particular with increased cost efficiency and a particularly compact design. Advantageously, at least one component of the induction hob device can provide at least two functions, in particular with regard to step-up conversion and emission of an electromagnetic wave with a frequency greater than an AC voltage operating the step-up converter unit. In particular, an output power of the emission induction unit can be adjusted particularly advantageously. Advantageously, the step-up converter unit can increase efficiency, in particular by reducing power loss for an increased voltage.

[0008] An “induction hob device” should be understood to mean, in particular, at least one part, in particular a subassembly, of an induction hob. The induction hob device preferably comprises at least one part of an electrical and / or electronic circuit of the induction hob and / or can, for example, comprise the entire electrical and / or electronic circuit. It is conceivable for the induction hob device to comprise only the boost converter unit. Alternatively, the induction hob device can also comprise the entire induction hob. The induction hob device is preferably provided for connection to at least one voltage source, in particular to an AC voltage source, preferably to a mains voltage source. The induction hob device is preferably connected to the at least one voltage source at least in one operating state.The voltage source is provided, in particular, to provide a main voltage, in particular an alternating voltage, preferably a mains voltage. Alternatively, it is conceivable for the main voltage to be different from a mains voltage and for the voltage source to be designed, for example, as a generator or the like. Alternatively, it would be conceivable for the induction hob device to have the voltage source, for example the generator, which is electrically connected, in particular at least in one operating state, to the boost converter unit.

[0009] The emission induction unit is provided, in particular, for emitting inductive energy for energy transmission to a mounting unit. The emission induction unit has, in particular, an emission induction element, preferably an inductance element, in particular a coil element, preferably an induction coil. The emission induction unit preferably has precisely one emission induction element. The emission induction unit preferably has at least one ferrite element, in particular at least one ferrite tile. The ferrite element is preferably designed as a ferrite core of the emission induction element, in particular of the coil element, and is in particular provided at least to reduce or prevent electromagnetic interference in the emission induction element. Alternatively, the emission induction unit can be formed from the emission induction element, in particular from a single induction coil.Preferably, the emission induction unit, in particular at least the emission induction element, is provided to heat the installation unit by means of the inductive energy and / or to supply it with an electrical current. The emission induction unit is preferably designed as an energy transfer inductor, in particular as a heating inductor and / or a power supply inductor. When the installation unit is placed on a mounting plate of the induction hob, for example the induction hob device, above the at least one emission induction unit, the inductive energy can preferably be transferred to the installation unit by means of the at least one emission induction unit. The mounting plate can be designed as a hob plate or as a kitchen worktop or as a table. The at least one emission induction unit is arranged in particular below the mounting plate.In this document, position designations such as "below" or "above" preferably refer to an installation position, in particular the mounted state, of the induction hob, preferably the induction hob device, unless explicitly described otherwise. The installation unit is preferably designed as a cooking utensil or as a small household appliance. The cooking utensil is designed, for example, as a pot, a pan, a roasting pan, or as another cooking utensil that a person skilled in the art would consider appropriate. The small household appliance is preferably designed to be portable and, in particular, can be transported manually by the operator.The small household appliance is preferably designed as a small cooking appliance, in particular as a small cooking appliance, and in particular has at least one electrical functional unit, for example an electric motor and / or a sensor unit and / or the like, which can be operated by means of the inductive energy. The small household appliance can, for example, be designed as a food processor, a rice cooker, an air fryer, a blender, a juicer, a kettle, a coffee maker, a smart pot and / or the like. The induction hob device, in particular the emission induction unit, can have at least one shielding element, in particular at least one aluminum sheet or the like. The shielding element is provided in particular for shielding against electromagnetic radiation and is preferably arranged below the emission induction element.The boost converter unit is provided in particular for increasing an output voltage, in particular provided in the emission induction unit, compared to an input voltage provided by the voltage source. The boost converter unit preferably has at least one boost inductance unit. The boost converter unit, in particular the emission induction unit acting as a boost inductance unit, is provided in particular for converting energy between energy stored in a magnetic field of the emission induction unit and electrical energy. The boost converter unit preferably has at least one, in particular exactly one, bus capacitor. The bus capacitor is preferably designed as an output capacitor, in particular as a charging capacitor, and is provided in particular for summing the output voltage, in particular a boosted voltage.The boost inductance unit preferably comprises a boost inductance element, preferably the inductance element, in particular the coil element. The boost inductance unit is preferably designed as a boost inductor. The boost inductance unit can comprise the ferrite element and / or the shielding element. Alternatively, the boost inductance unit can be formed from the boost inductance element, in particular from the single induction coil of the emission induction unit. The boost inductance unit and the emission induction unit preferably each comprise the same components and are in particular formed from the same components. The boost inductance element and the emission induction element are preferably formed integrally with one another. "Integral" is to be understood in particular as being formed in one piece.The boost inductance element and the emission induction element are in particular formed from the same component, in particular the same coil element, preferably from the same induction coil. Preferably, the boost inductance unit and the emission induction unit have the same, in particular uninterrupted, coil element. Preferably, the emission induction element, in particular the coil element, functions as the boost inductance element. Preferably, the emission induction unit, in particular at least the emission induction element, is provided to be traversed by a main current originating from the voltage source, in particular for boosting, and by an emission current, in particular for emitting the inductive energy. The emission current is preferably embodied as an alternating output current originating from the bus capacitor.The boost converter unit is preferably provided to output the emission current and / or an emission voltage. An envelope of the emission current is preferably smooth, wherein, in particular, acoustic noise caused by a magnetic field generated by overvoltage peaks can be reduced or avoided. The fact that the emission induction unit is provided to function as the boost inductance unit should be understood in particular to mean that the emission induction unit is provided for a boost function, which can in particular be assigned to a boost inductance unit of a conventional boost converter known to those skilled in the art. The coil element, in particular the induction coil, of the emission induction unit is in particular provided to function as a boost coil.The boost converter unit, preferably the induction hob device, is provided, at least for providing a boost conversion, apart from the coil element of the at least one emission induction unit and the at least one boost inductance unit, preferably free of a further coil element, preferably free of at least one further boost coil, outside the emission induction unit. The boost converter unit is preferably designed free of a boost coil, separate from the emission induction unit and / or outside an emission region of the induction hob. It is conceivable for the induction hob device to have a further coil, in particular different from a boost coil, for a function different from the boost conversion, for example a filter coil, in particular an EMC filter or the like.The boost converter unit could comprise at least one snubber for power devices, for example switching elements and the like, of the boost converter unit, whereby in particular efficiency and / or EMC performance can be improved.

[0010] "Intended" should be understood as specifically programmed, designed, and / or equipped. The fact that an object is intended for a specific function should be understood as meaning that the object fulfills and / or performs this specific function in at least one application and / or operating state.

[0011] It is further proposed that the boost converter unit be designed as a non-resonant boost converter unit, which in particular allows the number of components to be further reduced. Advantageously, cost efficiency can be further increased and, in particular, a particularly compact design of the induction hob device can be achieved. The non-resonant boost converter unit is preferably designed free of a capacitor, in particular one designed separately from the bus capacitor, in particular free of a resonance capacitor. The induction hob device is preferably designed free of the resonance capacitor, wherein the induction hob device can have, for example, at least one further capacitor, in particular at least one filter capacitor, for example of the EMC filter unit, in addition to the bus capacitor.

[0012] It is also proposed that the boost converter unit comprise only one rectification unit with, in particular, only two rectification elements, which is in particular assigned to the at least one emission induction unit. Advantageously, the number of components can be further reduced. The rectification unit is in particular provided at least to convert at least one alternating voltage and / or an alternating current, in particular the main voltage and / or the main current, into a direct voltage and / or a direct current, in particular into the input voltage and / or the input current. The rectification unit is preferably designed as a full-wave rectifier, which in particular can increase the efficiency of the induction hob device.The fact that the rectification unit is assigned to the emission induction unit should be understood in particular to mean that the rectification unit, in particular for rectifying the main current and / or the main voltage, is provided to supply the at least one emission induction unit and in particular is connected to the latter for supplying the latter. Preferably, at any selected point in time, in particular only one of the rectification elements is in an activated state. An activated state should be understood in particular to mean a conductive state. A first rectification element of the rectification elements is preferably activated for a first, for example positive, polarity of the main voltage. For the in particular positive first polarity of the main voltage, a current, in particular at least the main current, preferably flows along a first current direction.A second rectifying element of the rectifying elements is preferably activated for a second polarity of the main voltage, in particular one opposite to the first polarity, for example a negative one. For the second polarity of the main voltage, in particular a negative one, a current, in particular the main current, preferably flows along a second current direction, in particular opposite to the first current direction. Preferably, in particular depending on the polarity of the main voltage, an activated rectifying element of the voltage source and the emission induction unit is actively interposed. Preferably, the activated first rectifying element, in particular for the first polarity of the main voltage, is connected downstream of the voltage source and in particular upstream of the emission induction unit, in particular with respect to the first current direction.The activated first rectification element is preferably connected upstream of the bus capacitor, particularly with respect to the first current direction, in particular for the first polarity of the main voltage. The activated second rectification element is preferably connected upstream of the voltage source, particularly for the second polarity of the main voltage, and downstream of the emission induction unit, particularly with respect to the second current direction. The rectification unit, in particular at least one respective rectification element, is preferably provided to block a discharge path of the bus capacitor outside the emission induction unit. The first rectification element is preferably designed as a high-side rectification element. The second rectification element is preferably designed as a low-side rectification element.A central node of a connection of the boost converter unit between the first rectifying element and the second rectifying element is preferably connected to the at least one voltage source. The central node between the rectifying elements is preferably connected at least downstream of the voltage source along the first current direction and in particular upstream along the second current direction. The rectifying elements are preferably each connected at least to the bus capacitor on a side of the rectifying elements facing away from the central node between the at least two rectifying elements. The rectifying unit is preferably connected in the boost converter unit in such a way that the rectifying elements process only low-frequency current, in particular only the main current, preferably with a frequency of a maximum of 100 Hz, preferably of a maximum of 70 Hz and, for example, of 50 Hz or 60 Hz.The rectification unit can be designed to process only the low-frequency current, in particular only the main current, whereby in particular a simpler and / or more cost-efficient design of the rectification unit can be achieved. A respective rectification element is preferably designed as a diode, which is operated in the forward direction, in particular in the activated state. The first rectification element preferably has a forward direction along the first current direction, and in particular a reverse direction along the second current direction. The second rectification element preferably has a forward direction along the second current direction, and in particular a reverse direction along the first current direction.Alternatively, a respective rectifying element can be designed as a rectifying switching element, preferably as a semiconductor switching element, in particular as a transistor switching element and preferably as a MOSFET switching element. Alternatively, the rectifying switching element can be designed as another semiconductor switching element that appears appropriate to a person skilled in the art, or as a switching element that differs from a semiconductor switching element. The rectifying switching element preferably has switching dynamics capabilities in the kilohertz range. A control unit of the induction hob device is preferably provided to control a respective rectifying switching element depending on the polarity of the main voltage. The induction hob device preferably has at least one determination unit for determining the polarity of the main voltage.The control unit is preferably provided to control the rectification unit depending on the polarity of the main voltage, in particular depending on the determination of the determination unit.

[0013] Alternatively, it would be conceivable that the rectification unit has only one or more than two rectification elements.

[0014] It is further proposed that the boost converter unit comprise at least two emission induction units, each of which is in particular assigned to only one of the same rectification units. In particular, the two emission induction units, in particular by means of the two emission induction elements, can advantageously provide an induction hob with at least two separate energy transfer zones, in particular heating zones, and / or with at least one variable energy transfer area, for example in a matrix design of the induction hob. The at least two emission induction units can in particular jointly provide a variable energy transfer area and / or each a single energy transfer area. Advantageously, the number of components, in particular with regard to the rectification unit, can be further reduced.Preferably, the same, in particular only one, rectification unit is assigned to each emission induction unit of the boost converter unit, in particular of the induction hob device and preferably of the entire induction hob. Preferably, the at least two emission induction units are each assigned to the same, in particular two, rectification elements. Preferably, all emission induction units of the boost converter unit, in particular of the induction hob device and preferably of the entire induction hob, are each assigned to the same, in particular two, rectification elements. The emission induction units each have, in particular, an emission induction element, in particular the induction coil, which can be identical to one another or can differ from one another, for example with regard to a number of turns and / or a turn thickness and / or a length and / or a cross-sectional area.The emission induction units preferably each have at least one ferrite element and / or at least one shielding element. Preferably, each emission induction unit functions as a boost inductance unit. Preferably, each emission induction element functions as a boost inductance element.

[0015] Alternatively, it would be conceivable for the rectification unit to have more than one rectification unit, each of which is assigned to at least one, in particular exactly one, emission induction unit.

[0016] It is further proposed that the boost converter unit comprise a bus capacitor, in particular the one mentioned above, wherein the at least two emission induction units are each assigned to the bus capacitor. Advantageously, the number of components can be further reduced. The fact that the bus capacitor is assigned to the emission induction units should be understood in particular to mean that the bus capacitor is provided to supply the emission induction units, in particular by means of the output voltage, and in particular is connected to the emission induction units for supplying them. The bus capacitor is preferably connected to the emission induction units for boost conversion, in particular for summing and providing the output voltage. Preferably, the boost converter unit, preferably the induction hob device and preferably the induction hob, comprises only one bus capacitor.The bus capacitor is preferably assigned to each emission induction unit of the boost converter unit, in particular of the induction hob device and preferably of the entire induction hob, and is in particular intended to supply each emission induction unit, in particular by means of the at least one output voltage. The bus capacitor is preferably connected to all emission induction units for boost conversion. Alternatively, the boost converter unit and / or the induction hob device can have more than one bus capacitor, each of which is preferably assigned to more than one emission induction unit. Alternatively, it would be conceivable for at least one bus capacitor of the boost converter unit and / or the induction hob device to be assigned, in particular, to a single emission induction unit.

[0017] In one embodiment of the invention, the boost converter unit is provided for converting, in particular, boosting, at least, in particular only, a single-phase alternating current. However, in an advantageous embodiment of the invention, it is proposed that the boost converter unit is provided for converting, in particular, boosting, a multi-phase alternating current. Advantageously, the induction hob device, in particular the boost converter unit, is provided to be operated by a multi-phase alternating current, for example, a two-phase alternating current and / or a three-phase alternating current. The number of components of the induction hob device, and in particular of the induction hob, can advantageously be further reduced.Furthermore, a power supply and / or control architecture can be simplified, advantageously achieving savings in the power supply and / or a number of measuring devices and / or isolation devices. Preferably, the boost converter unit, in particular a respective emission induction unit, is provided to convert an alternating current of a single phase of the multi-phase alternating current. The multi-phase alternating current is preferably provided by the at least one voltage source. Preferably, an alternating current with a single phase of the multi-phase alternating current is provided to supply a respective emission induction unit. A respective emission induction unit can be provided to boost a respective alternating current with a single phase of the multi-phase alternating current.The emission current, in particular an envelope of the emission current, in a respective emission induction unit preferably has a periodicity according to a periodicity of a respective main current and / or a main voltage, in particular of a single phase of the multi-phase alternating current.

[0018] Furthermore, it is proposed that the boost converter unit comprise a rectification unit, in particular the one mentioned above, which is provided for rectifying all phases of the multiphase alternating current. In particular, the number of components of the induction hob device can be further reduced. Advantageously, a current through the rectification elements can be reduced due to current feedback between the phases, which in particular can improve efficiency. In particular, the rectification unit, in particular the same rectification elements, is provided for rectifying each respective alternating current with a single phase of the multiphase alternating current.

[0019] It is further proposed that the boost converter unit comprise a bus capacitor, which is designed to be supplied by all phases of the multiphase alternating current. Advantageously, the number of components of the induction hob device can be further reduced. In particular, an advantageous output voltage for supplying the at least one emission induction unit, in particular for generating the emission current, can be provided in the bus capacitor. Advantageously, residual ripple, in particular of the output voltage in the bus capacitor, can be reduced.

[0020] It is further proposed that the boost converter unit has at least one inverter unit, in particular the one mentioned above, and at least one control unit, in particular the one mentioned above, at least for adjusting a duty cycle and / or a frequency of the inverter unit to adjust an output power of the at least one emission induction unit, whereby in particular the output power can be adjusted particularly advantageously. Preferably, the output power can be adjusted particularly precisely by means of the duty cycle and / or the frequency. The inverter unit is preferably provided at least for providing the emission current and / or the emission voltage based on the output current and / or the output voltage. The control unit is provided in particular at least for controlling the inverter unit. A “control unit” should be understood in particular as a unit with at least one control electronics unit.The term "control electronics" should be understood, in particular, as a unit comprising a processor unit and a memory unit, as well as an operating program stored in the memory unit. The control unit is preferably designed to control the inverter unit at least as a function of the polarity of the main voltage, in particular as a function of a determination by the determination unit, and in particular as a function of the output power to be achieved, set, for example, by an operator and / or a corresponding program. The control unit is preferably connected, in particular electrically and / or electronically, to a user interface of the induction hob device and / or the induction hob, at which the output power to be achieved can be set, in particular.The control unit is preferably provided to control the inverter unit to adjust the output voltage, in particular at least by adjusting the duty cycle. The duty cycle and / or the frequency of the inverter unit relate in particular to a switching characteristic of the inverter unit controlled by the control unit, and in particular to a control signal. The duty cycle and / or the frequency of the inverter unit correspond in particular to a duty cycle and / or a frequency of the emission voltage and / or the emission current. The control unit is preferably provided to adapt the duty cycle for the first polarity and the second polarity of the main voltage. The duty cycle can differ in particular for the first polarity and the second polarity of the main voltage.A sum of the duty cycle of the first polarity of the main voltage and the duty cycle of the second polarity of the main voltage is preferably 1, whereby in particular an advantageous, in particular symmetrical, output voltage can be achieved in the bus capacitor.

[0021] The inverter unit preferably has at least one inverter switching element. The inverter switching element is preferably designed as a semiconductor switching element, in particular as a transistor switching element and preferably as a MOSFET switching element. Alternatively, the inverter switching element can be designed as any other semiconductor switching element deemed appropriate by a person skilled in the art, or as a switching element different from a semiconductor switching element. The inverter switching element preferably has switching dynamics capabilities in the kilohertz range. The control unit is preferably provided to control the at least one inverter switching element at least as a function of the polarity of the main voltage and in particular as a function of the output power to be achieved, set, for example, by the operator and / or the program.The control unit is particularly provided for controlling the at least one inverter switching element. The duty cycle and, in particular, the frequency of the inverter unit relate, in particular, to a switching characteristic of the at least one inverter switching element controlled by the control unit. The inverter unit preferably has at least two, in particular exactly two, inverter switching elements for each, in particular for each, emission induction unit, wherein the at least two, in particular exactly two, inverter switching elements are each assigned to a respective emission induction unit. The at least one emission induction unit is preferably assigned to a respective half-bridge of the inverter unit. The frequency can be the same for all respective half-bridges of the inverter unit, wherein, in particular, intermodulation products can advantageously be avoided.The duty cycle preferably differs for each phase of the multi-phase alternating current. The inverter unit preferably has, in particular for each emission induction unit, a first inverter switching element, which is in particular designed as a high-side inverter switching element. The control unit can be provided to activate the first inverter switching element for the second polarity of the main voltage, in particular at least for generating the emission current, in particular periodically. The control unit can be provided to activate the first inverter switching element simultaneously with the second rectification element, in particular periodically. The inverter unit preferably has, in particular for each emission induction unit, at least one second inverter switching element, which is in particular designed as a low-side inverter switching element.The control unit can be provided to activate the second inverter switching element for the first polarity of the main voltage, in particular at least for generating the emission current, in particular periodically. The control unit can be provided to activate the second inverter switching element simultaneously with the first rectifier element, in particular periodically. A middle node of a connection of the boost converter unit between the first inverter switching element and the second inverter switching element is preferably connected to the at least one, in particular to a respective, emission induction unit. The inverter switching elements are preferably each connected at least to the bus capacitor on a side of the inverter switching elements remote from the middle node between the at least two inverter switching elements.

[0022] It is also proposed that the control unit be provided for adjusting an output power of the at least one emission induction unit at a fixed frequency of the one inverter unit. Advantageously, frequency-dependent filtering of at least one filter unit, for example the EMC filter unit, of the induction hob device, in particular for filtering an interference current and / or an interference voltage outside the fixed frequency and / or at the fixed frequency, can be provided particularly efficiently and / or precisely. In particular, the complexity of the filter unit can be reduced and / or the cost and / or space efficiency of the filter unit can be advantageously increased. Preferably, the control unit is provided only for adjusting the duty cycle, in particular at the fixed frequency, of the inverter unit for adjusting the output power of the at least one emission induction unit.In particular, operator comfort can be advantageously increased by reducing acoustic noise when operating the induction hob device at the fixed frequency.

[0023] Furthermore, a method for operating an induction hob device, in particular the one mentioned above, with at least one boost converter unit, in particular the one mentioned above, which has at least one emission induction unit, in particular the one mentioned above, is proposed. The emission induction unit is operated as a boost inductance unit, in particular the one mentioned above. Advantageously, the number of components of the induction hob device can be reduced. In particular, different process sequences of the method can run simultaneously within a respective component of the induction hob device.The method preferably comprises at least one method step, in particular a switching step, in which a control unit, in particular the above-mentioned, controls at least one, in particular the above-mentioned, inverter unit, which is preferably supplied with an output voltage, in particular the above-mentioned, by a bus capacitor, in particular the above-mentioned. The control unit controls, in particular switches, during control of the inverter unit, preferably at least on, in particular the at least one above-mentioned inverter switching element of the inverter unit. The control unit switches the inverter unit, in particular in the switching step, preferably at a frequency greater than a frequency of a main voltage, in particular the above-mentioned, of at least one voltage source, in particular the above-mentioned.The control unit preferably adjusts, in particular in the switching step, at least one circuit parameter, preferably a duty cycle and / or a frequency, of the inverter unit, in particular to adjust the output voltage and / or an output power of the emission induction unit. The control unit controls the inverter unit, in particular in the switching step, preferably depending on at least one setting, in particular at least one manual operator setting and / or an autonomous machine setting, for example when the control unit autonomously follows a recipe, with regard to an output power to be achieved. The control unit controls the inverter unit, in particular in the switching step, preferably depending on a polarity, in particular the polarity mentioned above, of the main voltage.The control unit can, in particular in the switching step, control a rectification unit, in particular the one mentioned above, wherein the rectification unit in particular has the rectification elements mentioned above designed as rectification switching elements. The control unit controls at least the inverter unit, in particular in the switching step, preferably for a boost sequence of the method. In the boost sequence, the emission induction unit preferably converts energy, in particular between magnetically stored energy and electrical energy, to increase the output voltage at the bus capacitor compared to an input voltage, in particular provided by the at least one voltage source. Preferably, the control unit controls at least the inverter unit, in particular in the switching step, for an emission sequence of the method.In the emission sequence, the emission induction unit is preferably operated by an inverted emission current, in particular by means of the inverter unit, which is preferably supplied by the output voltage provided in the bus capacitor.

[0024] The induction hob device, the induction hob, and the method for operating the induction hob device are not intended to be limited to the application and embodiment described above. In particular, the induction hob device, the induction hob, and the method for operating the induction hob device may have a number of individual elements, components, units, and method steps that differs from the number stated herein to fulfill a functionality described herein.

[0025] Further advantages will become apparent from the following description of the drawings. The drawings illustrate exemplary embodiments of the invention. The drawings, the description, and the claims contain numerous features in combination. Those skilled in the art will also expediently consider the features individually and combine them into useful further combinations.

[0026] They show:

[0027] Fig. 1 A schematic plan view of an induction hob with an induction hob device,

[0028] Fig. 2 is a circuit diagram of the induction hob device with a boost converter unit connected to a voltage source,

[0029] Fig. 3 is a circuit diagram of the induction hob device with a marked current intensity for (a) a positive polarity of the voltage source and (b) a negative polarity of the voltage source,

[0030] Fig. 4 exemplary graphs for currents, voltages and a switching characteristic in the boost converter unit for an output power of 3600 W of an emission coil of the induction hob device, (a) in an overview view and (b) enlarged in time resolution,

[0031] Fig. 5 exemplary graphs for currents, voltages and a switching characteristic in the boost converter unit for an output power of 3000 W of an emission coil of the induction hob device,

[0032] Fig. 6 exemplary graphs for currents, voltages and a switching characteristic in the boost converter unit for an output power of 500 W of an emission coil of the induction hob device, (a) in an overview view and (b) enlarged in time resolution,

[0033] Fig. 7 is a flowchart of a method for operating the induction hob device,

[0034] Fig. 8 is a circuit diagram of an alternative embodiment of the induction hob device, with two emission coils and a single-phase voltage source,

[0035] Fig. 9 exemplary graphs for currents and voltages in the induction hob device according to Figure 8,

[0036] Fig. 10 is a circuit diagram of an alternative embodiment of the induction hob device, with two emission coils and two voltage sources, each providing an alternating current with different phases,

[0037] Fig. 11 exemplary graphs for currents and voltages in the induction hob device according to Figure 10 and

[0038] Fig. 12 is a circuit diagram of an alternative embodiment of the induction hob device, with an alternative rectification unit.

[0039] Figure 1 shows a schematic plan view of an induction hob 50a with an induction hob device 10a.

[0040] The induction hob 50a has a support plate 52a for mounting a support unit 54a. The support unit 54a is embodied as a pot in the present case, but alternatively, it could also be designed as any other cooking utensil or small household appliance deemed appropriate by a person skilled in the art.

[0041] The induction hob 50a has at least one user interface 56a. The user interface 56a is provided at least for an operator (not shown) to adjust the output power of the induction hob 50a, in particular of an emission induction unit 14a of the induction hob device 10a. The user interface 56a and / or the support plate 52a could be part of the induction hob device 10a.

[0042] The induction hob device 10a has at least one control unit 30a. The control unit 30a is electrically and / or electronically connected to the user interface 56a.

[0043] Figure 2 shows a simplified circuit diagram of the induction hob device 10a. The induction hob device 10a has at least one boost converter unit 12a. The boost converter unit 12a is connected to at least one voltage source 40a. In this case, the boost converter unit 12a is designed to convert only a single-phase alternating current from the voltage source 40a.

[0044] The boost converter unit 12a is provided at least to convert an input voltage provided by the voltage source 40a into a boosted output voltage. The input voltage and / or a corresponding input current is / are embodied as a direct voltage and / or a direct current. The output voltage and / or a corresponding output current is / are embodied as a direct voltage and / or a direct current.

[0045] The voltage source 40a outputs a main voltage. The main voltage is embodied as an alternating voltage, in this case a single-phase one. The main voltage is embodied as a mains voltage. For example, the main voltage has a frequency of 50 Hz. Alternatively, it is conceivable that the voltage source 40a provides a different mains voltage, for example, with a frequency of 60 Hz, or an alternating voltage different from a mains voltage.

[0046] The boost converter unit 12a is provided for converting the main voltage output from the voltage source 40a into an emission voltage. The emission voltage and / or a corresponding emission current is / are embodied as an alternating voltage and / or as an alternating current. The emission voltage has a higher amplitude than the main voltage. The emission voltage has a higher frequency than the main voltage. The boost converter unit 12a has at least one rectifier unit 18a for generating the input voltage from the main voltage.

[0047] The boost converter unit 12a has only one rectification unit 18a with two rectification elements 28a, 38a. In this case, the rectification unit 18a has only two rectification elements 28a, 38a. The rectification unit 18a is assigned to the emission induction unit 14a.

[0048] The rectification unit 18a is designed as a full-wave rectifier. The rectification unit 18a has a first rectification element 28a and a second rectification element 38a. The rectification elements 28a, 38a are each designed as diodes 48a, 58a.

[0049] The rectification elements 28a, 38a are each designed as a high-side rectification element and a low-side rectification element. The first rectification element 28a is designed as the high-side rectification element. The second rectification element 38a is designed as the low-side rectification element.

[0050] The boost converter unit 12a has, in particular, a bus capacitor 20a. The bus capacitor 20a is designed as an output capacitor. The bus capacitor 20a is provided for summing the output voltage based on the input voltage. The output voltage is, in particular at least in magnitude, greater than the main voltage.

[0051] The boost converter unit 12a has at least one inverter unit 22a. The inverter unit 22a is provided for generating the emission voltage and / or the emission current at the emission induction unit 14a using the output voltage and / or the output current.

[0052] The inverter unit 22a has at least one inverter switching element 32a, 42a. In this case, the inverter unit 22a has exactly two inverter switching elements 32a, 42a. The inverter unit 22a has a first inverter switching element 32a. The first inverter switching element 32a is designed as a high-side inverter switching element. The inverter unit 22a has a second inverter switching element 42a. The second inverter switching element 32a is designed as a low-side inverter switching element. The inverter switching elements 32a, 42a are each designed as a semiconductor switching element. The inverter switching elements 32a, 42a are each designed as a MOSFET switching element. Alternatively, the inverter switching elements 32a, 42a can be designed as another switching element that appears appropriate to a person skilled in the art.

[0053] The boost converter unit 12a has at least one emission induction unit 14a. The emission induction unit 14a is designed to emit inductive energy for energy transmission to the at least one mounting unit 54a. The emission induction unit 14a has precisely one emission induction element 24a.

[0054] The emission induction element 24a is embodied as an inductance element 44a. The emission induction element 24a is embodied as a coil element 46a. The coil element 46a is embodied as a one-piece coil. Alternatively, the inductance element 44a could be embodied as any other subcircuit that would be deemed appropriate to one skilled in the art and / or as any other element with a corresponding inductance that would be deemed appropriate to one skilled in the art.

[0055] The emission induction unit 14a is designed as an energy transfer inductor.

[0056] The emission induction unit 14a may include at least one ferrite element (not shown). The ferrite element may be formed as a ferrite core of the emission induction element 24a.

[0057] The emission induction unit 14a may have at least one shielding element (not shown) for shielding electromagnetic radiation below the emission induction element 24a.

[0058] For a more illustrative illustration, the emission induction unit 14a here has a representative equivalent resistance 62a, which represents losses at the emission induction unit 14a, which in particular occur at least largely at the installation unit 54a and / or in cable connections of the induction hob device 10a. The emission induction unit 14a is shown here as being formed from the emission induction element 24a and the equivalent resistance 62a connected in series therewith. The emission induction unit 14a is intended to inductively heat the installation unit 54a and / or to supply it with electrical energy (see Figure 1). The energy can be transferred to the installation plate 52a above the emission induction unit 14a for installing the installation unit 54a. The emission induction unit 14a is arranged below the installation plate 52a.

[0059] The boost converter unit 12a is designed as a single-stage boost converter unit 12a, which has both a rectification function and an inverter function.

[0060] The emission inductance unit 14a is provided to function as a boost inductance unit 16a. The boost converter unit 12a has the boost inductance unit 16a for boost conversion. The boost inductance unit 16a is provided to provide the increased output voltage in the bus capacitor 20a. The boost inductance unit 16a has precisely one boost inductance element 26a. The boost inductance element 26a is embodied as the inductance element 44a. The boost inductance element 26a is embodied as the coil element 46a.

[0061] The boost inductance element 26a is formed integrally with the emission inductance element 24a. The boost inductance element 26a and the emission inductance element 24a are formed from the same inductance element 44a, in particular from the same coil element 46a.

[0062] The boost inductance unit 16a is designed as a boost inductor. The boost inductance unit 16a can include the ferrite element and / or the shielding element.

[0063] The boost inductance unit 16a has the representative equivalent resistance 62a. The emission inductance unit 14a and the boost inductance unit 16a are each formed from the same components as each other.

[0064] The emission induction unit 14a, which functions in particular as a boost inductance unit 16a, is provided for converting energy stored in a magnetic field of the emission induction unit 14a into electrical energy. The inductance element 44a is provided for converting the energy. The boost converter unit 12a is designed as a non-resonant boost converter unit 12a. The boost converter unit 12a is designed without a resonant capacitor, which is designed in particular separately from the bus capacitor 20a.

[0065] The control unit 30a is intended to control at least the inverter unit 22a, in particular the inverter switching elements 32a, 42a. The control unit 30a is intended to control the inverter unit 22a at least as a function of a polarity of the main voltage. The control unit 30a is intended to control the inverter unit 22a as a function of a desired output power, which is set, for example, at the user interface 56a.

[0066] The control unit 30a is provided at least for adjusting a duty cycle of the inverter unit 22a to adjust an output power of the at least one emission induction unit 14a.

[0067] The control unit 30a is provided for adjusting the output power of the at least one emission induction unit 14a at a fixed frequency of the inverter unit 22a. Alternatively or additionally, it is conceivable that the control unit 30a is provided for adjusting the frequency of the inverter unit 22a to adjust the output power of the at least one emission induction unit 14a.

[0068] Figure 3a shows the circuit diagram from Figure 2 for a first polarity, in this case particularly positive, of the main voltage of the voltage source 40a. A main current caused by the voltage source 40a flows along a first current direction 64a.

[0069] The first rectifying element 28a has a forward operation for a circuit along the first current direction 64a. The first rectifying element 28a is activated for the first polarity of the main voltage.

[0070] The second rectification element 38a (shown in gray here) has a blocking mode for the circuitry along the first current direction 64a. The second rectification element 38a is deactivated for the first polarity of the main voltage.

[0071] Along the first current direction 64a, the bus capacitor 20a is connected downstream of the rectification unit 18a, in particular the activated first rectification element 28a.

[0072] Along the first current direction 64a, the inverter unit 22a, in particular the second inverter switching element 42a, is connected downstream of the bus capacitor 20a. Along the first current direction 64a, the emission induction unit 14a is connected downstream of the inverter unit 22a.

[0073] A voltage between a point of the circuit immediately before the second rectifying element 38a along its forward direction and the voltage source 40a is, for the first polarity of the main voltage, a value of a difference between the voltage in the bus capacitor 20a and the main voltage.

[0074] Figure 3b shows the circuit diagram from Figure 2 for a second polarity, in particular negative in this case, of the main voltage of the voltage source 40a. The main current caused by the voltage source 40a flows in a second current direction 66a.

[0075] The second rectifying element 38a has a forward operation for connection along the second current direction 66a. The second rectifying element 38a is activated for the second polarity of the main voltage.

[0076] The first rectifying element 28a (shown in gray here) has a blocking mode for the circuitry along the second current direction 66a. The first rectifying element 28a is deactivated for the second polarity of the main voltage.

[0077] The rectifying elements 28a, 38a are designed to activate in opposite directions to each other depending on the polarity of the main voltage. Each activated rectifying element 28a, 38a is interposed along the respective current direction 64a, 66a of the voltage source 40a and the emission induction unit 14a.

[0078] A voltage between the point of the circuit immediately before the second rectifying element 38a along its forward direction and the voltage source 40a is a value of the main voltage for the second polarity of the main voltage.

[0079] Figure 4a shows exemplary graphs for an output power of the emission induction unit 14a, in particular of the emission induction element 24a, of 3600 W.

[0080] A top graph shows an axis 74a plotting voltage in volts against an axis 72a plotting time in milliseconds. A curve 80a shows the main voltage with the first, specifically the positive, and the second, specifically the negative, polarity of a period of the main voltage. A curve 82a shows the output voltage in bus capacitor 20a. The output voltage has an amplitude greater than the amplitude of the main voltage.

[0081] A middle graph shows an axis 76a of current in amperes versus the axis 72a of time in milliseconds. A curve 84a shows the main current in the emission induction unit 14a, respectively during the first and second polarity of the main voltage.

[0082] A curve 86a shows an envelope of the emission current in the emission induction unit 14a. Due to the upconversion, an amplitude of the envelope of the emission current is greater than an amplitude of the main current.

[0083] A lower graph shows an axis 78a of the duty cycle of the inverter unit 22a plotted against the time axis 72a in milliseconds. A curve 88a shows the duty cycle during the first and second polarity of the main voltage, respectively.

[0084] The control unit 30a is designed to adjust the duty cycle according to the set output power. The control unit 30a is designed to adjust the duty cycle for the first polarity and the second polarity of the main voltage. In this case, the duty cycle differs for the first polarity and the second polarity of the main voltage. The sum of the duty cycle for the first polarity of the main voltage and the duty cycle for the second polarity of the main voltage is 1.

[0085] Figure 4b shows a time segment of the emission current curve 86a of the middle graph of Figure 4b, plotted on an axis 96a of current in amperes versus an axis 90a of time in milliseconds, with increased time resolution. A curve 94a shows the emission voltage on an axis 92a of voltage in volts. The emission voltage alternates between a value of the output voltage at a corresponding time and zero.

[0086] A frequency of the emission current is greater than a frequency of the main current (see Figure 4a). A frequency of the emission voltage is greater than a frequency of the main voltage (see Figure 4a). The frequency of the emission voltage is 50 kHz in this example. Alternatively, another emission voltage that would be considered appropriate by a person skilled in the art is conceivable, which is advantageously at least one order of magnitude higher than the frequency of the main voltage.

[0087] Figure 5 shows exemplary graphs for an output power of the emission induction unit 14a, in particular of the emission induction element 24a, of 3000 W. The graphs correspond analogously to the graphs of Figure 4a, whereby only curves which differ from the curves of Figure 4a will be explained below.

[0088] The topmost graph shows a curve 102a, which represents the output voltage in bus capacitor 20a. An amplitude of the output voltage in bus capacitor 20a results in a reduction in the output power compared to the output voltage and output power in Figure 4a. The output power rises and falls according to a maximum amplitude of the output voltage in bus capacitor 20a.

[0089] A middle graph shows a curve 104a, which represents the main current. A curve 106a shows an envelope of the emission current in the emission-induction unit 14a. The amplitude of the emission current envelope is reduced to a reduction in the output power compared to the emission current and the output power in Figure 4a. The output power rises and falls with the amplitude of the emission current envelope in the emission-induction unit 14a.

[0090] A lower graph shows a curve 108a, which shows the duty cycle of the inverter unit 22a.

[0091] Figure 6a shows exemplary graphs for an output power of the emission induction unit 14a, in particular the emission induction unit 14a, of 500 W. The graphs correspond analogously to the graphs of Figures 4a and 5, whereby only curves which differ from the curves of Figures 4a and 5 will be mentioned below.

[0092] A top graph shows a curve 112a, which shows the output voltage in the bus capacitor 20a.

[0093] A middle graph shows a curve 114a, which represents the main current. A curve 116a shows an envelope of the emission current in the emission induction unit 14a. A lower graph shows a curve 118a, which represents the duty cycle of the inverter unit 22a.

[0094] Figure 6b, corresponding to Figure 4b, shows a time segment of curve 116a of the emission current in the middle graph of Figure 6a. Curve 120a shows the emission voltage. The output power rises and falls according to a maximum amplitude of the emission voltage in the emission induction unit 14a.

[0095] Figure 7 shows a flowchart for a method for operating the induction hob device 10a, wherein the emission induction unit 14a is operated as a boost inductance unit 16a.

[0096] The method includes a switching step 200a in which the control unit 30a controls the inverter unit 22a. In the switching step 200a, the control unit 30a adjusts the duty cycle of the inverter unit 22a to adjust the output power of the emission induction unit 14a. The control unit 30a controls the inverter unit 22a in the switching step 200a depending on an operator setting on the operator interface 56a (see Figure 1). The control unit 30a controls the inverter unit 22a in the switching step 200a depending on the polarity of the main voltage.

[0097] The control unit 30a controls the inverter unit 22a in the switching step 200a to a boost sequence 202a of the method. In the boost sequence 202a, the emission induction unit 14a converts energy between magnetically stored energy and electrical energy to summate the output voltage in the bus capacitor 20a.

[0098] In switching step 200a, control unit 30a controls inverter unit 22a to an emission sequence 204a of the method. In emission sequence 204a, emission induction unit 14a is operated with the emission current to transmit the inductive energy to mounting unit 54a.

[0099] Of multiple objects present, only one is provided with a reference symbol in the figures. Figures 8 to 12 show three further exemplary embodiments of the invention. The following descriptions are essentially limited to the differences between the exemplary embodiments, whereby with regard to identical components, features and functions reference can be made to the description of the exemplary embodiment in Figures 1 to 7. To differentiate the exemplary embodiments, the letter a in the reference symbols of the exemplary embodiment in Figures 1 to 7 has been replaced by the letter b in the reference symbols of the exemplary embodiment in Figures 8 and 9, by the letter c in the reference symbols of the exemplary embodiment in Figures 10 and 11, and by the letter d in the reference symbols of the exemplary embodiment in Figure 12.With regard to components with the same designation, in particular with regard to components with the same reference numerals, reference can in principle also be made to the drawings and / or the description of the embodiment of Figures 1 to 2.

[0100] Figure 8 shows an alternative embodiment of an induction hob device 10b with at least one boost converter unit 12b. The boost converter unit 12b is provided here for converting only a single-phase main current from a voltage source 40b.

[0101] The boost converter unit 12b has at least two emission induction units 14b, 34b. The at least two emission induction units 14b, 34b each function as a boost inductance unit 16b, 36b.

[0102] Each emission induction unit 14b, 34b has an emission induction element 24b, with only one emission induction element 24b being designated. Each emission induction element 24b functions as a boost inductance element 26b, with only one boost inductance element 26b being designated.

[0103] The at least two emission induction units 14b, 34b are each assigned to the same rectification unit 18b of the boost converter unit 12b. The rectification unit 18b has only two rectification elements 28b, 38b.

[0104] An inverter unit 22b of the boost converter unit 12b has exactly two inverter switching elements 32a, 42b, which are each jointly assigned to an emission induction unit 14b. The boost converter unit 12b has a bus capacitor 20b, with the at least two emission induction units 14b, 34b each being assigned to the bus capacitor 20b. The boost converter unit 12b has only one bus capacitor 20b.

[0105] Figure 9 shows exemplary graphs relating to the boost converter unit 12b of Figure 8.

[0106] A top graph shows a curve 80b of a main voltage and a curve 124b of the main current over an axis 122b of a time.

[0107] A middle graph is associated with the emission induction unit 14b and shows a curve 126b of an output voltage in the bus capacitor 20b and a curve 128b of an emission current in the emission induction unit 14b over the time axis 122b.

[0108] A lower graph is associated with the further emission induction unit 34b and shows a curve 130b of an emission current in the further emission induction unit 34b.

[0109] Figure 10 shows an alternative embodiment of an induction hob device 10c with at least one boost converter unit 12c, wherein in the following, in particular, changes with regard to the embodiment of the induction hob device 10b of Figures 8 and 9 will be mentioned.

[0110] The boost converter unit 12c is provided here for converting a multi-phase alternating current. The multi-phase alternating current is provided by a voltage source 40c and a further voltage source 60c. The voltage source 40c and the further voltage source 60c each provide a single-phase alternating voltage, with the phases differing from one another.

[0111] The voltage source 40c and the further voltage source 60c can, for example, be part of a two-phase alternating current connection or a three-phase alternating current connection for connection to a corresponding power grid.

[0112] The boost converter unit 12c has a rectification unit 18c, which is intended to rectify all phases of the multi-phase alternating current.

[0113] The boost converter unit 12c includes a bus capacitor 20c, which is designed to be supplied by all phases of the multiphase alternating current. Figure 11 shows exemplary graphs relating to the boost converter unit 12c of Figure 10.

[0114] A top graph shows a curve 132c of a main voltage of the voltage source 40c of a first phase and a curve 134c of a corresponding main current versus a time axis 122c. The graph shows a curve 136c of a main voltage of the further voltage source 60c of a second phase and a curve 138c of a corresponding main current versus the time axis 122c.

[0115] A middle graph is associated with an emission induction unit 14c and shows a curve 140c of an output voltage in the bus capacitor 20c and a curve 142c of an emission current with the first phase in the emission induction unit 14c over the time axis 122c.

[0116] A lower graph is associated with a further emission induction unit 34c and shows a curve 144c of an emission current with the second phase in the further emission induction unit 14c over the time axis 122c.

[0117] Figure 12 shows an alternative embodiment of an induction hob device 10d with at least one boost converter unit 12d. The boost converter unit 12d of Figure 12 differs from the boost converter unit 12c of Figure 10 by an alternative embodiment of the rectifying elements 28d, 38d of a rectifying unit 18d of the boost converter unit 12d. In the following, particular changes to the embodiment of the induction hob device 10c of Figures 10 and 11 will be mentioned.

[0118] The rectifying elements 28d, 38d are designed as rectifying switching elements 68d, 70d. The rectifying switching elements 68d, 70d are each designed as a semiconductor switching element. The rectifying switching elements 68d, 70d are each designed as a MOSFET switching element.

[0119] Alternatively, the rectifying switching elements 68d, 70d can be designed as another semiconductor switching element that would be deemed appropriate by a person skilled in the art, or as a switching element that differs from a semiconductor switching element. A control unit 30d of the induction hob device 10d is provided to control the rectifying unit 18d. The control unit 30d is provided to activate precisely one of the rectifying elements 28d, 38d depending on the polarity of a main voltage. The induction hob device 10d exhibits a behavior corresponding to the graphs in Figure 11.

[0120] Reference symbol

[0121] 10 Induction hob device

[0122] 12 Boost converter unit

[0123] 14 Emission induction unit

[0124] 16 Boost inductance unit

[0125] 18 Rectification unit

[0126] 20 Bus capacitor

[0127] 22 Inverter unit

[0128] 24 Emission induction element

[0129] 26 Boost inductance element

[0130] 28 first rectifying element

[0131] 30 Control unit

[0132] 32 first inverter switching element

[0133] 34 additional emission induction units

[0134] 36 additional boost inductance units

[0135] 38 second rectifying element

[0136] 40 Voltage source

[0137] 42 second inverter switching element

[0138] 44 Inductance element

[0139] 46 coil element

[0140] 48 diodes

[0141] 50 induction hob

[0142] 52 mounting plate

[0143] 54 Installation unit

[0144] 56 User interface

[0145] 58 additional diodes

[0146] 60 additional voltage source

[0147] 62 equivalent resistance

[0148] 64 first current direction second current direction

[0149] Rectifying switching element

[0150] Rectifying switching element

[0151] axis

[0152] axis

[0153] axis

[0154] axis

[0155] curve

[0156] curve

[0157] curve

[0158] curve

[0159] curve

[0160] axis

[0161] axis

[0162] curve

[0163] axis

[0164] curve

[0165] curve

[0166] curve

[0167] curve

[0168] curve

[0169] curve

[0170] curve

[0171] curve

[0172] curve

[0173] axis

[0174] curve

[0175] curve

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[0177] curve

[0178] Curve Curve

[0179] curve

[0180] curve

[0181] curve

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[0183] curve

[0184] Circuit step

[0185] Boost process

[0186] Emission process

Claims

Claims 1. Induction hob device (10a-10d) with at least one boost converter unit (12a-12d), wherein the boost converter unit (12a-12d) has at least one emission induction unit (14a-14d), characterized in that the emission induction unit (14a-14d) is intended to function as a boost inductance unit (16a-16d).

2. Induction hob device (10a-10d) according to claim 1, characterized in that the up-converter unit (12a-12d) is designed as a non-resonant up-converter unit (12a-12d).

3. Induction hob device (10a-10d) according to claim 1 or 2, characterized in that the boost converter unit (12a-12d) has only one rectifying unit (18a-18d) with two rectifying elements (28a-28d, 38a-28d).

4. Induction hob device (10b; 10c; 10d) according to one of the preceding claims, characterized in that the boost converter unit (12b; 12c; 12d) has at least two emission induction units (14b; 14c; 14d, 34a; 34d; 34c).

5. Induction hob device (10b; 10c; 10d) according to claim 4, characterized in that the boost converter unit (12b; 12c; 12d) has a bus capacitor (20b; 20c; 20d), wherein the at least two emission induction units (14b; 14c; 14d, 34a; 34d; 34c) are each assigned to the bus capacitor (20b; 20c; 20d).

6. Induction hob device (10c; 10d) according to one of the preceding claims, characterized in that the step-up converter unit (12c; 12d) is provided for converting a multi-phase alternating current.

7. Induction hob device (10c; 10d) according to claim 6, characterized in that the boost converter unit (12c; 12d) has a rectification unit (18c; 18d) which is provided to rectify all phases of the multi-phase alternating current.

8. Induction hob device (10c; 10d) according to claim 6 or 7, characterized in that the boost converter unit (12c; 12d) comprises a bus capacitor (20c; 20d) which is intended to be supplied by all phases of the multi-phase alternating current.

9. Induction hob device (10a-10d) according to one of the preceding claims, characterized in that the boost converter unit (12a-12d) has at least one inverter unit (22a-22d) and at least one control unit (30a-30d) at least for adjusting a duty cycle and / or a frequency of the inverter unit (22a-22d) to adjust an output power of the at least one emission induction unit (14a-14d).

10. Induction hob device (10a-10d) according to claim 9, characterized in that the control unit (30a-30d) is provided for adjusting an output power of the at least one emission induction unit (14a-14d) at a fixed frequency of the inverter unit (22a-22d).

11. Induction hob (50a) with an induction hob device (10a-10d) according to one of the preceding claims.

12. A method for operating an induction hob device (10a-10d), in particular according to one of claims 1 to 10, with at least one boost converter unit (12a-12d) which has at least one emission induction unit (14a-14d), characterized in that the emission induction unit (14a-14d) is operated as a boost inductance unit (16a-16d).

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