A system for adaptive preheating of a magnetron within a microwave oven is disclosed. In embodiments, the system includes temperature sensors for sensing a magnetron temperature. The system includes a power supply controller in communication with the microwave's power supply and the temperature sensors and including control processors. The power supply controller receives a requested power setting associated with a cooking cycle, e.g., selected by a user via a human-machine interface of the microwave oven. Before the cooking cycle commences, the power supply controller calculates a preheat time based on the sensed magnetron temperature. After starting a timer corresponding to the determined preheat time, the power supply controller preheats the filament by applying sufficient current to render the filament incandescent and so the resonant cavities may be stimulated. By preheating the filament, the system reduces operational fatigue on the filament due to cold starts.

A combination microwave and refrigerator system is provided. The microwave oven is connected to a source of power and has a control circuit for controlling the operation of the microwave oven. A first power supply outlet is provided on the microwave oven. A refrigerator is connected to the source of power by connection to the first power supply outlet. The control circuit is configured to disable the cooling operation of the refrigerator, when the microwave oven demands cooking power, and enable the cooling operation of the refrigerator when the microwave oven is not drawing cooking power. A safety sensor is provided in the microwave oven, and is configured to cause cooking power to the microwave oven to be turned off upon the safety sensor sensing a dangerous condition.

An interrupting circuit (44) is configured to monitor for and detect a fault in a device (10) for generating a field of electromagnetic radiation (e-field) (34) from a radio frequency (RF) generator (24) configured to convert low voltage direct current (DC) into the e-field (34) for application to an article in the e-field (34). If a fault is detected, the interrupting circuit (44) interrupts low voltage DC between an energy reserve (46, 48) and the RF generator (24) within a predetermined time less than the time to dissipate energy stored in the energy reserve (46, 48).

An electronic transformer and a microwave cooking appliance. The electronic transformer comprises a rectifier device, a transformer, a switch device, and a control device. The rectifier device is connected to an alternating current source; the transformer is connected to the rectifier device; the switch device is configured to provide an on/off signal to the transformer; the control device is connected to the switch device; the control device is configured to generate a control signal according to preset power and provide the control signal to the switch device to control the switching frequency of the switch device.

An RF energy radiation device includes a cavity in which a heating target object is to be placed, an RF signal generation unit, an RF amplifier, a radiation element, a temperature sensor, and a controller. The RF signal generation unit oscillates an RF signal. The RF amplifier amplifies the RF signal and provides RF energy. The radiation element radiates the RF energy into the cavity. The temperature sensor is disposed in the vicinity of the RF amplifier. The controller controls the RF amplifier so that the RF amplifier adjusts the RF energy output in accordance with the temperature detected by the temperature sensor and a plurality of threshold levels. This aspect can improve the reliability of the device.

A microwave heating apparatus and methods of controlling cooling of a microwave heating apparatus are provided. The microwave heating apparatus typically includes a microwave source for generating microwaves, a cooling unit for cooling the microwave source and a control unit. According to one embodiment, the control unit is configured to receive operational data from a measuring device indicative of the measured power of microwaves transmitted from the magnetron and receive operational data from the measuring device indicative of the measured anode current of the magnetron. A calculating device calculates an efficiency of the magnetron as a function of the measured power of the transmitted microwaves and the measured anode current, to define a determined efficiency. The control unit controls the cooling unit and cools the magnetron based on the determined efficiency.

A method for managing a microwave heating device able to operate based on a first signal having a first fundamental harmonic frequency that is within the microwave range, wherein operation of the microwave heating device (1) is interrupted or modified when, inside the microwave heating device (1), the presence of a second signal is detected, the latter having harmonic components which have frequencies that are different from a fundamental harmonic frequency and an intensity higher than a critical reference value.

Different aspects of the invention refer to a disinfection apparatus, and corresponding method, for wood barrel disinfection using microwave shock pulse, MwSP, technology for the complete elimination of microbial populations. This is accomplished by a system which ensures deep and complete disinfection, however such that the temperature is maintained below material degradation level. Complete disinfection is achieved due to effectiveness up to the deepest layers. The wooden barrel material is however preserved, due to the non-harmful nature of the dosage regime programmed into the radio frequency emission.

An interrupting circuit is configured to monitor for and detect a fault in a device for generating a field of electromagnetic radiation (e-field) from a radio frequency (RF) generator configured to convert low voltage direct current (DC) into the e-field for application to an article in the e-field. If a fault is detected, the interrupting circuit interrupts low voltage DC between an energy reserve and the RF generator within a predetermined time less than the time to dissipate energy stored in the energy reserve.

An RF system includes an RF signal source and a single-ended or double-ended impedance matching network. Non-linear devices, such as gas discharge tubes, are coupled in parallel with components of the impedance matching network. The non-linear devices are insulating below a breakdown voltage and conductive above the breakdown voltage. The system also includes measurement circuitry configured to measure one or more parameters that reflect changes in the impedance of the impedance matching network. A system controller modifies operation of the system when a rate of change of any of the monitored parameter(s) exceeds a predetermined threshold.