Abstract: The present invention is a heater or heating device that uses microwave energy to generate heat quickly. The heater generates heat quickly by forcing air over microwave-heated oil or non-freeze liquid. As a non-limiting embodiment, the heater preferably includes most or all of the following components: an outer casing or housing, at least one air intake vent, a magnetron, a microwave emitter, a wave scatterer, at least one fluid holder, fluid, a capacitor, a transformer, a microwave containment casing, and a perforated microwave guard. As another non-limiting embodiment, the heater preferably includes most or all of following components: an outer casing or housing, a cooling fan, a magnetron, a microwave emitter, a wave scatterer, at least one non-freeze liquid holder, non-freeze liquid, a capacitor, a transformer, a microwave containment casing, a glass tube, a metal tube, a fan coil, a pump, a reservoir and expansion tank, and a fill plug.

Abstract: A circuit support structure includes a first metal layer, a second metal layer, isolation material containing the first and second metal layers, an isolation circuit, a first plurality of contact pads, and a second plurality of contact pads. The isolation circuit includes a first circuit element in the first metal layer and a second circuit element in the second metal layer and electrically isolated from the first circuit element by the isolation material. The first plurality of contact pads is adapted to be coupled to a first integrated circuit on the circuit support structure and includes a first contact pad electrically coupled to the first circuit element. The second plurality of contact pads is adapted to be coupled to a second integrated circuit on the circuit support structure and includes a second contact pad electrically coupled to the second circuit element.

Abstract: A frequency controller for operating a switching power converter is provided. The frequency controller includes an output circuit, an operation signal generator, and a transition signal generator. The output circuit is to connect to a switching power converter. The startup signal generator is connected to the output circuit via a first connection line and configured to generate a startup signal with a startup-frequency during a startup period of the switching power converter. The operation signal generator is connected to the output circuit via a second connection line and configured to generate an operation signal with an operation-frequency during an operation period of the switching power converter. The transition signal generator is connected to the output circuit via a third connection line and configured to generate a transition signal with varied frequencies during a transition period between the startup period and the operation period.

Abstract: A method and apparatus for delivering radio frequency electromagnetic energy to cook foodstuff in an enclosed cavity of a cooking device includes generating, with a small signal generating component, a radio frequency signal at a first power level, amplifying the radio frequency signal to a second power level greater than the first power level with a radio frequency amplification component, and feeding the amplified radio frequency signal to the enclosed cavity.

Abstract: A method and apparatus for delivering radio frequency electromagnetic energy to cook foodstuff in an enclosed cavity of a cooking device includes generating, with a small signal generating component, a radio frequency signal at a first power level, amplifying the radio frequency signal to a second power level greater than the first power level with a radio frequency amplification component, and feeding the amplified radio frequency signal to the enclosed cavity.

Abstract: A power supply unit with galvanic isolation for converting an input-side alternating or direct voltage into an output-side direct voltage in a clocked manner, includes a first primary circuit that has a series circuit consisting of a primary coil of a transformer and a first switch element and a first control circuit, at least one secondary circuit that has a secondary coil of the transformer and a smoothing capacitor that is parallel to an output direct voltage of the secondary circuit, a second primary circuit that has a series circuit consisting of a part of the primary coil and a second switch element for pulse length modulation of the voltage at the part of the primary coil, and a voltage evaluator that switches either the first or the second switch element for the next switching cycle depending on the level of the input voltage in order to obviate PFC circuits or a voltage multiplication.

Abstract: A system and a method for adjusting a power of an inverter of a microwave oven, and a microwave oven are provided. The system (100) includes: a storage module (101), configured to store an index table comprising periodic counting values and identification numbers; a control module (102), configured to look up an identification number corresponding to a power request signal in the index table according to the power request signal, to look up a periodic counting value corresponding to the identification number in the index table, and to output a frequency signal according to the periodic counting value; and a communication module (104), configured to output a power control signal to the inverter (106) of the microwave oven according to the frequency signal. The inverter (106) outputs a power to a magnetron (108) of the microwave oven according to the power control signal.

Abstract: An apparatus is provided for heating plastic preforms, having a plurality of resonator units, into which in each case plastic preforms can be introduced in order to heat the latter, having at least one microwave generating unit for generating microwaves, and having a feed device for feeding to at least one resonator unit the microwaves generated by the microwave generating unit, and having at least one rectifier unit for providing a rectified voltage. Further, at least one rectifier unit provides voltage for operating at least two resonator units.

Abstract: Voltage transformer (A) and rectifier (B1), (B2) meant for power supply for LED lamps wherein the mentioned transformer (A) comprises a three-phase primary winding and at least two three-phase secondary windings wherein the outputs (1u, 1 v, 1 w) and (2u, 2v, 2w) of the mentioned secondary windings are connected to the rectifiers (B1) and (B2). The secondary windings are divided for several primary windings with various phases and are connected with various connections between outputs of the secondary windings in order to create the desired phase differences or the secondary windings have each their own primary winding wherein the connections between the outputs of the secondary windings have a characteristic, desired phase difference.

Abstract: A power converter comprises a switch network coupled to an input voltage, a power transformer having a primary winding and a secondary winding, wherein the primary winding is coupled to the switch network, and the secondary winding is coupled to a rectifier, wherein the rectifier is coupled to an output voltage, a primary resonant tank having a first resonant capacitor and a first resonant frequency, and coupled to the primary winding of the power transformer and the switch network, and a regulation circuit configured to control the output voltage of the power converter to be substantially proportional to the input voltage and the switch network to operate at a frequency substantially close to the first resonant frequency.

Abstract: A high frequency cathode heater supply for a microwave source includes a SMPS inverter and an isolation transformer having a primary winding arranged to be powered by the SMPS inverter, a monitor winding passing through primary core assemblies of the primary winding and a secondary winding arranged for connection to the cathode heater. A current monitor is arranged to monitor a current in the primary windings. Signal processing modules are arranged to receive a first input signal from the monitor winding indicative of a voltage across the cathode heater and a second input signal from the current monitor indicative of a current through the cathode heater. The signal processing modules are arranged to output a control signal to the SMPS inverter to control power supplied to the cathode heater dependent on a monitored resistance of, or monitored power supplied to, the cathode heater as determined from the first input signal and the second input signal.

Abstract: Provided is an infrared radiation cooker in which heat from an infrared lamp is directly applied onto food being grilled, to thus cook the upper and inner parts of the food, as well as onto a rotatable pan, to thus simultaneously cook the lower part of the food. As a result, the food cooks evenly throughout without burning or creating residual odors from above to below as well as from outer to inner, and further the rotatable pan of respectively different structures can be selected depending on an intended cooking purpose, to thereby adjust height of the rotatable pan, which changes a heat intensity, to thus vary a cooking style, and which can be used to boil, grill or roast foods as one would like.

Abstract: A microwave heating device mountable to an electric device, includes: a commercial power supply; an AC/DC converter which outputs a plurality of DC voltages according to power supplied from the commercial power supply; a controller which receives power from the AC/DC converter and totally controls the electric device; a microwave processing device using a compound semiconductor which receives a plurality of outputs of the AC/DC converter and outputs a microwave; and a plurality of loads connected between, of the DC voltages output from the AC/DC converter, a predetermined Vd voltage and ground through a plurality of contacts. The loads form a group of electric components in the electric device. The controller controls power supply to the loads, and controls on/off of the contacts to drive the loads by the Vd voltage regardless of the voltage of the commercial power supply.

Abstract: An appliance including a cabinet having a first PCB located therein, a door connected to the cabinet, the door being moveable between an open position and a closed position to open and close the cabinet, and a second PCB located in the door. In addition, at least one first connector is connected to the first PCB. At least one second connector is connected to the second PCB and is electronically connectable to the first connector. In particular, the second connector is electrically connected to the first connector when the door is in a substantially closed position.

Abstract: A microwave oven is capable of preventing a door that can be opened from a left side or a right side thereof from being simultaneously opened from both sides thereof. The microwave oven includes a body, a door, and a change device. The door is coupled with the body. The change device allows the door to be opened from both sides thereof. The change device includes a pair of holders, a pair of sliders, and at least one lever. The holders rotate as the door is opened from both sides thereof. The sliders linearly move in cooperation of the holders. The at least one lever restricts the linear movement of the sliders when the door is opened from one side thereof, thereby preventing the door from being open from a remaining side.

Abstract: A power control unit for high-frequency dielectric heating is provided. The power control unit controls an inverter circuit for rectifying voltage of an AC power supply, and modulates the on time of a switching transistor during high frequency switching. The power control unit includes an input current detection section for detecting input current from the AC power supply to the inverter circuit and outputting input current waveform information. A conversion section is provided for converting the input current waveform information into a drive signal of the switching transistor of the inverter circuit so that an instantaneous fluctuation of the input current waveform information is suppressed.

Abstract: The high-frequency heating device, the subject of the present invention, is driven by an inverter and, by reducing the power losses in the mentioned inverter the operating efficiency is increased.

Abstract: An inverter controller controls an inverter. The inverter converts direct current into alternating current of a predetermined frequency. The inverter includes a resonance circuit for fluctuating output of a predetermined object to be controlled. The inverter controller comprises an output fluctuating unit which fluctuates output of the inverter in response to an output value of a temperature detection section which detects a temperature of a switching element of the inverter. The inverter controller further comprises an output increase suppressing unit which suppresses an increase in the output of the inverter for a predetermined time after decrease control in the output of the inverter performed by the output fluctuating unit.

Abstract: A user interface arranged at least to display, on a display unit or on a display panel, information relative to the operation of a household electrical appliance with which the interface is associated, the appliance presenting functional members controlled in their operation by a control unit, and an external housing provided with an aperture with its own closure door; the interface is positionable on and fastenable to the exterior of the housing of the electrical appliance, remote wire-less data communication and transmission means being associated with the control unit and with the interface to enable the data to be transmitted from the interior of the electrical appliance to the interface through the housing. A household electrical appliance with this interface is also claimed.

Abstract: A power control unit for high-frequency dielectric heating is provided, and includes an input current detection section for detecting input current from the AC power supply to the inverter circuit and outputting input current waveform information. A conversion section converts the input current waveform information into a drive signal of the switching transistor of the inverter circuit so that instantaneous fluctuation of the input current waveform information is suppressed. A mix circuit mixes the input current waveform information and power control information for controlling so that current or voltage at an arbitrary point of the inverter circuit becomes a predetermined value and generates an on voltage signal. The conversion section converts the on voltage signal into the drive signal so that the on time is shortened in the portion where the input current is large and that the on time is prolonged in the portion where the input current is small.

Abstract: A system, method, and computer-readable medium for controlling power applied to a heating element. A rectifier receives AC voltage supplied from an AC voltage supply and rectifies the AC voltage to DC voltage. A pulse-width modulation controller generates and transmits a pulse-width modulation signal, and a DC voltage modulator receives the DC voltage from the rectifier and the pulse-width modulation signal from the pulse-width modulation controller. Based on the pulse-width modulation signal, the DC voltage modulator supplies an analog DC voltage signal to the heating element. A feedback circuit reports the actual DC voltage applied to the heating element to a microcontroller and, if the actual DC voltage deviates from the DC voltage encoded in the pulse-width modulation signal, the pulse-width modulation controller modulates the pulse-width modulation signal to minimize or eliminate the deviation.

Abstract: A microwave processing apparatus includes: a processing chamber; a microwave introducing unit for generating microwaves and introducing the microwaves into the chamber; and a control unit for controlling the microwave introducing unit. The microwave introducing unit has microwave sources for generating the microwaves and transmission lines for transmitting the microwaves into the chamber and introduces parts of the microwaves into the chamber simultaneously, and the control unit switches a first state of introducing said parts of the microwaves into the chamber to a second state of generating a microwave by one of the microwave sources and introducing into the chamber.

Abstract: A system and methods are disclosed for providing a double line break having a secondary power break to function components in a microwave oven. The double line break includes at least two power switches, such as relay devices that provide back-up protection in case one switch fails, or a primary interlock switch corresponding to a door of the oven.

Abstract: A variable-frequency oscillator 1, a semiconductor power amplifier 2 for amplifying the output of the variable-frequency oscillator 1; a radiator 3 for radiating an electromagnetic wave for heating based on the output of the semiconductor power amplifier 2; a reflected wave monitoring circuit 5 for detecting a reflected wave of the electromagnetic wave for heating; and a controller 7 for controlling the oscillation frequency of the variable-frequency oscillator 1 are provided. The controller 7 changes the oscillation frequencies of the variable-frequency oscillator 1 discontinuously, thereby getting a frequency-hopping spread-spectrum radiation done by the radiator 3. The electromagnetic wave radiated by the radiator 3 irradiates an object 9 to be heated (which is usually food) inside a heating chamber 8, thereby heating the object.

Abstract: To attain a more reliable prevention of an electric shock by checking whether the earth states for two circuit boards are good. There is detected a voltage generated at an anode current sensing resistor 20 inserted into a path where the anode current of a magnetron 8 flows and a signal is transmitted to a microcomputer 27. The microcomputer 27 uses a selector switch 28 to determine the earth states for an inverter circuit board and a control panel circuit board before operation of a device. In case either one or both of the circuit boards are in a floating state, operation of a high-frequency heating device is inhibited. Otherwise, operation of the high-frequency heating device is permitted.

Abstract: A power control unit for high-frequency dielectric heating is provided. The power control includes an input current detection section for detecting input current from an AC power supply to an inverter circuit and outputting input current waveform information. A conversion section converts the input current waveform information into a drive signal of the switching transistor of the inverter circuit so that instantaneous fluctuation of the input current waveform information is suppressed. An input voltage detection section detects input voltage from the AC power supply to the inverter circuit and outputs input voltage waveform information. A selection section selects the input current waveform information or the input voltage waveform information, whichever is larger. The conversion section also converts the selected input current waveform information or input voltage waveform information into the drive signal of the switching transistor of the inverter circuit.

Abstract: A magnetron driving power source can detect the abnormal condition during no-load running with low cost and space saving. The magnetron driving power source includes a high voltage transformer (12) for supplying a high voltage to a magnetron (11), a switching part (13) for driving the high voltage transformer at a high frequency, a first control part (14) for giving a drive signal to the switching part, a second control part (16) for issuing an output command to the first control part, and a third control part (19) for correcting the output command in accordance with a decrease in the oscillation threshold value of the magnetron, wherein the first control part (14) performs a power down control in accordance with a signal from the third control part. Accordingly, the magnetron driving power source of the invention can treat the signal on the control side of the inverter and detect the abnormal condition during no-load running with low cost and space saving.

Abstract: An object of the present invention is to provide an inverter circuit in which soft start can be implemented by a simple circuit added thereto. In high-frequency heating apparatus for driving a magnetron, a DC power supply is chopped by two semiconductor switching devices, and this is output as an AC current through a resonance circuit. The high-frequency heating apparatus includes a dead time generation circuit for turning off the semiconductor switching devices concurrently. In the high-frequency heating apparatus, a drive unit for driving the aforementioned semiconductor switching devices has a function of limiting the lowest frequency of a frequency with which the semiconductor switching devices are driven. The aforementioned lowest frequency is set to be high at the beginning of operation of the high-frequency heating apparatus, and the aforementioned lowest frequency is set to be lower gradually thereafter.

Abstract: A convection system for an oven comprising a baffle defining a single heating chamber mounted within a cavity of the oven, a heating element located within the single heating chamber for heating air within the heating chamber, and at least two fans located within the heating chamber. The oven cavity can be defined, in part, by a wall having at least a portion with a curved peripheral edge, so that air exhausted through the outlet is deflected away from the wall.

Abstract: A latch board of a microwave oven is provided. The latch board includes a first lever for controlling on/off operation of a monitor switch. The first lever is formed in an approximate triangular shape and has a hinge formed at a first edge, a pressing part formed at a second edge to come in contact with the monitor switch, and a protrusion part formed at a third edge to come in contact with the latch more rapidly. In the latch board, a difference in operation time of the monitor switch and the circuit switch can be increased such that the operation stability of the microwave oven is improved.

Abstract: Disclosed is a microwave oven capable of preventing leakage of microwaves by using a plurality of primary switches, a plurality of secondary switches and a plurality of monitor switches. The primary switches are serially connected with each other, the secondary switches are connected in parallel with each other, and the monitor switches are connected in parallel with each other, so that the microwave oven does not operate if a door of the microwave oven is not completely closed.

Abstract: Occurrence of a defect of the moding phenomenon, etc., accompanying rise in output of a magnetron after power down control is prevented and the reliability of a high-voltage dielectric heating apparatus is further improved. After power down control, when the temperature of a thermistor T1 falls again, the resistance value of the thermistor T1 increases and potential Vpc at a point PC also rises and when the potential Vpc becomes higher than Vc3 of another input potential of a comparator C3 (Vpc>Vc3), the comparator C3 outputs “0.” In association with this, a switch S2 is turned off and PD (power down) 2 of a resistor R7 is turned off and thus the input voltage to a positive terminal A and a negative terminal B of a comparator C1 is again restored to 3 V. When the temperature of the thermistor T1 further falls, the resistance value of the thermistor T1 increases and the potential Vpc at the point PC also starts to rise.

Abstract: It is an object of the present invention to provide a power supply for a high frequency heating that suppresses an over-shoot of an input current generated under an unstable state immediately after a magnetron begins oscillating. When processes from a non-oscillation to an oscillation of a magnetron (12) are finely classified, the non-oscillation (a start mode), the oscillation (a start mode) and the oscillation (a steady mode) are obtained. A problem resides in an unstable state immediately after the oscillation. When a PWM setting value at this time is set to a value lower than a PWM setting value in the steady mode, even if the PWM setting value during the steady mode is set to a maximum output value, the input current is not controlled to a large current including the over-shoot immediately after the oscillation.

Abstract: There is constructed a constitution such that a shunt resistor 30 is interposed in series with a portion capable of measuring an output current of a unidirectional power source portion 1 of a high frequency heating apparatus and a voltage generated at the shunt resistor 30 is outputted by a buffer 31. Further, an operational amplifier 3101 having a high input impedance is used for the buffer 31. Further, a diode bridge 101 and a semiconductor switching element 205 are fixed to a common heat radiating plate 33, the heat radiating plate 33 is formed with a notched portion 33a to thereby ensure insulating distances to the diode bridge 101 and the semiconductor switching element 205, and the shunt resistor 30 is arranged on a straight line the same as that between the diode bridge 101 and the semiconductor switching element 205.

Abstract: According to the present invention, a microwave generator includes a variable voltage provided from a first transformer to a second transformer having a secondary winding split into a filament winding cathode low AC signal and a secondary winding providing a high voltage which is doubled and rectified in a half-wave voltage doubler for providing a pulsed DC signal through a ballast resistor to a magnetron anode responsive to an electromagnetic field. In still further accord with the present invention, a microwave sample cavity includes a waveguide, and a hole for receiving a sample to be microwave-heated, and an inductive tuning post all on a straight line, wherein the hole is adjacent the waveguide and the post is distant from the waveguide.

Abstract: Disclosed herein is a cooking apparatus and cooking system which allows a user to change cooking information that is suitable to the preferences of the user and the amount of food when cooking food using automatic cooking information, and a cooking control method using the same. The cooking apparatus using automatic cooking information includes an automatic cooking information acquisition unit for acquiring the automatic cooking information; an automatic cooking information change unit for allowing a user to change the acquired automatic cooking information; and a control unit for controlling a series of cooking operations on the basis of the changed cooking information.

Abstract: A purpose of the present invention is to provide an inverter circuit capable of firmly turning ON IGBTs under limited condition, while a heat loss and noise can be hardly produced in semiconductor switching elements.

Abstract: An apparatus for controlling an inverter circuit of an induction heat cooker which generates and outputs high voltage power to cook food contained in a cooking container is disclosed. The apparatus varies a pulse width of high level interval of a driving pulse according to a level of AC power supplied thereto to vary a switch current of the inverter circuit, and sufficiently secures a turn off time of the driving pulse in proportion to a resonant time varying according to states of separation of the cooking container or the heated food. Therefore, the apparatus improves stability of the switching operation and endurance. Also the apparatus requires relatively low manufacturing costs as the trigger generation is implemented with relatively low-priced amplifiers.

Abstract: A control method for a microwave oven equipped with a tray installed in a cooking chamber to rotate a popcorn bag while having a popcorn cooking mode to cook popcorn. During cooking, rotation of the tray is temporarily stopped near the point of time when the popcorn bag is increased in size to a maximum size. Accordingly, problems caused by the fact that the popcorn bag comes into contact with the inner wall surface of the cooking chamber so that it cannot rotate are solved. The popcorn cooking mode is an operation mode to cook a popcorn product with corn grains packed in the popcorn bag in a state in which it is folded at least one time. The rotation of the tray is temporarily stopped near the point of time when the popcorn bag is estimated to achieve its maximum length as a folded portion of the popcorn bag is unfolded.

Abstract: An oscillation control signal generated by an inverter power source control circuit (12) includes a reference voltage setting signal for approximating the current waveform of the AC output form the AC power source (1) to a sinusoidal wave by making both sides of the waveform generate current according to the fluctuation of the PWM control signal, and a waveform shaping signal consisting of a peak adjustment signal of a sinusoidal waveform for approximating the waveform peak portion of the current waveform to a sinusoidal wave by subtraction. Accordingly, even if the PWM control signal fluctuates, it is possible to automatically improve the power factor of the power source circuit to a value higher than a predetermined value by approximating the current waveform of the AC output from the AC power source to the sinusoidal wave, thereby improving the efficiency of the power source.

Abstract: A heating apparatus includes an inverter power supply for driving the high frequency generating device, a holding member for holding the inverter power supply and cooling fan for cooling down the inverter power supply. The holding member is provided with a holding portion for holding the inverter power supply and an air guide portion for guiding cooling air from the cooling fan toward the inverter power supply, and the air guide portion covers the inverter power supply and guides the cooling air in a manner that a semiconductor switching device and a high voltage transformer of the inverter power supply are primarily cooled down.

Abstract: A microwave oven is provided with an integrated operating unit having an integrated function for power supply, power level control, and inrush current suppression. The integrated operating unit includes a rotary dial, a shaft fixed, at one end thereof, to the rotary dial, a cam mounted about a concentric axis of the shaft to be rotated along with the shaft, and an iron core extending, at one end thereof, from the other end of the shaft away from the shaft beyond the cam. A relay coil is wound around the iron core. The integrated operating unit further includes a power switch attached to a support member extending from the other end of the iron core away from the iron core, an inrush switch for suppressing inrush current, and a power control switch for controlling the power supply time in accordance with a set power level.

Abstract: A method and apparatus for adaptively maintaining the power-frequency spectrum in a reverberation chamber. The invention is thus capable of maintaining a relatively constant power-frequency spectrum in the chamber even when a device under examination is placed into the chamber which exhibits selective frequency absorption and or directional frequency absorption. The object disposed within the chamber need not necessarily be a device under examination. Rather, the present invention can also adaptively maintain a relatively constant power-frequency spectrum when heating any material disposed within a electromagnetic wave chamber.

Abstract: A magnetron oscillating apparatus includes a magnetron, power supply unit, and switch circuit. The magnetron oscillates a microwave. The power supply unit applies a power to the magnetron. The switch circuit is connected between the power supply unit and the cathode of the magnetron and turned on/off on the basis of a control signal. When the switch circuit is turned on by the control signal, a voltage is applied between the cathode and the grounded anode of the magnetron to cause the magnetron to pulse-oscillate.

Abstract: A cooking apparatus, in which lamps are conveniently and quickly replaced, including a lamp assembly having a lamp casing accommodating lamps and covering an irradiation hole formed in a front panel, and a transparent plate completely covering the irradiation hole. The lamp casing is screwed to the front panel, or is hinged to the front panel to allow rotation of the lamp casing. An open bottom of the lamp casing is covered with a lamp cover screwed or hooked to the lamp casing. A front cover is screwed to the front panel to cover the lamp assembly, or is hinged to the front panel to allow rotation thereof.

Abstract: Disclosed herein are an inverter microwave oven and a method for controlling the same, wherein a switching frequency of an inverter is raised during the initial operation of the microwave oven and then lowered during the normal operation of the oven after the lapse of a predetermined time, so as to prevent overvoltage from being applied to a magnetron, which generates electromagnetic waves, during the initial operation, thereby enhancing durability and operational reliability of the inverter. The inverter microwave oven comprises a rectifier for rectifying and smoothing a commercial AC voltage into a DC voltage. The inverter is adapted to perform a switching operation based on the DC voltage from the rectifier to generate a magnetron drive AC voltage.

Abstract: An apparatus and method for controlling an output of a magnetron of a microwave oven is provided. The method includes setting an initial input current to generate an output higher than rated output. Thereafter, the magnetron is driven using initial input current of the setting. The output of the magnetron is varied within a preset time to prevent overheating caused by driving of the magnetron.

Abstract: Timing of zero voltage in zero-voltage detector for detecting zero voltage of a commercial power supply 1 is predicted and input from the zero-voltage detector 6 is received only for a given time before and after the predicted timing, whereby overvoltage and overcurrent caused by a zero point shift can be prevented. Thus, it is provided a magnetron drive power supply which is excellent in stability for change in the power supply environment such as noise or instantaneous power interruption.

Abstract: Circuit for operating a microwave oven including a DC voltage source, a switching part having at least two switching devices electrically connected to the DC voltage source for switching a voltage from the DC voltage source, controlling part for controlling the switching part, a magnetron for generating a microwave, and a converting part for converting the voltage from the DC voltage source to a voltage for operating the magnetron by switching of the switching part, thereby permitting operation of the microwave oven by using a car battery.

Abstract: A low-output microwave lighting system includes: a rectifier for rectifying general AC power inputted through a power source unit and outputting a DC voltage; a power factor compensator for compensating a power factor of the DC voltage inputted through the rectifier; and an inverter circuit unit for receiving the power factor-compensated DC voltage and outputting an AC voltage through frequency varying. 120 Hz of ripple generated at a low output can be reduce, and it is driven at a frequency of 20 KHz or higher, so that a flicker phenomenon does not occur and a volume and weight in facility can be reduced.