Power supply and its control method, heating device, and microwave cooking equipment

Abstract

The invention relates to a power supply (100) and its control method, a heating device (1000), and a microwave cooking device. The power supply (100) includes a rectifier and smoothing circuit (10), an inverter circuit (20), and a processing circuit (30). The inverter circuit (20) includes a transformer (21) and a switching element (22) connected to a primary coil (211), and the secondary coil (212) is connected to a magnetron (200). The rectifier and smoothing circuit (10) is connected to an AC power supply (300), and the primary coil (211) is connected to the rectifier and smoothing circuit (10). The processing circuit (30) controls the on / off state of the switching element (22), and if the detected electrical parameters of the switching element (22) meet preset conditions, it determines that the magnetron (200) is overheated and adjusts the electrical parameters so that the magnetron (200) is not overheated.

Description

Technical Field

[0001] This disclosure claims the priority and rights of the patent application with patent application number 202310555936.X filed with the China National Intellectual Property Administration on May 16, 2023, and incorporates the full text thereof by reference herein.

[0002] This disclosure relates to the technical field of kitchen electrical appliances, particularly to a drive power supply and its control method, a heating device, and a microwave cooking device.

Background Art

[0003] Currently, a microwave oven includes a magnetron, and the magnetron generates microwaves for heating food. The magnetron's temperature rises during operation. When operating under severe conditions (for example, when operating in a sealed state in a narrow kitchen where it is impossible to ensure intake and exhaust spaces, or when the magnetron operates in an unloaded state in the cavity) compared to normal usage conditions, the magnetron overheats, and a magnetron operated in an over-temperature state causes a shortening of its service life.

Summary of the Invention

Problems to be Solved by the Invention

[0004] Embodiments of this disclosure provide a drive power supply and its control method, a heating device, and a microwave cooking device.

[0005] Embodiments of the present disclosure provide a drive power supply. The drive power supply is used to supply power to a magnetron and includes a rectifier-smoothing circuit, an inverter circuit and a processing circuit, the inverter circuit includes a transformer and a switching element, the transformer includes a primary coil and a secondary coil, the switching element is connected to the primary coil and the secondary coil is used to connect to the magnetron, the rectifier-smoothing circuit is used to connect to an AC power supply and the primary coil is connected to the rectifier-smoothing circuit and the processing circuit is connected to the inverter circuit and is used to control the on / off state of the switching element, the processing circuit is used to detect the electrical parameters of the switching element, and to determine that the magnetron is in an over-temperature state if the electrical parameters of the switching element satisfy a preset condition and to adjust the electrical parameters of the switching element so that the magnetron is not in an over-temperature state.

[0006] The above-mentioned power supply detects the electrical parameters of the switching elements to determine if the magnetron is in an over-temperature state. By adjusting the electrical parameters of the switching elements so that the magnetron is not in an over-temperature state, it is possible to prevent the magnetron from operating in an over-temperature state for an extended period and extend the service life of the magnetron.

[0007] In some embodiments, the electrical parameters of the switching element include the voltage of the switching element.

[0008] In this way, the power supply can determine the temperature state of the magnetron by observing the voltage of the switching element via a voltage detection circuit and determining the magnitude of the magnetron's operating voltage.

[0009] In some embodiments, the switching element includes a transistor, the transistor includes a collector, the voltage of the switching element includes the voltage of the collector, the processing circuit includes a voltage detection circuit and an arithmetic circuit, the arithmetic circuit is connected to the voltage detection circuit, the voltage detection circuit is connected to the collector, the voltage detection circuit is used to detect the voltage of the collector, the arithmetic circuit determines that the magnetron is in an overtemperature state if the voltage of the collector satisfies the preset conditions, and is used to adjust the voltage of the collector so that the magnetron is not in an overtemperature state.

[0010] In this way, the arithmetic circuit determines that the magnetron is in an overheated state via the voltage of the switching element's collector, and adjusts the collector voltage to ensure the magnetron's normal operation.

[0011] In some embodiments, the electrical parameters of the switching element include the on-pulse width of the switching element.

[0012] In this way, the power supply can determine the temperature state of the magnetron by observing the on-pulse width of the switching element via a frequency detection circuit and determining the magnitude of the magnetron's operating voltage.

[0013] In some embodiments, the processing circuit includes a frequency detection circuit and an arithmetic circuit, the arithmetic circuit being connected to the frequency detection circuit, the frequency detection circuit being connected to the switching element, the frequency detection circuit being used to detect the on-pulse width of the switching element, and the arithmetic circuit determining that the magnetron is in an over-temperature state if the on-pulse width of the switching element satisfies the preset conditions, and is used to adjust the on-pulse width of the switching element so that the magnetron is not in an over-temperature state.

[0014] In this way, the calculation circuit determines that the magnetron is in an overheated state via the on-pulse width of the switching element, and adjusts the on-pulse width of the switching element to ensure the normal operation of the magnetron.

[0015] In some embodiments, the processing circuit is used to determine the operating voltage of the magnetron based on the electrical parameters of the switching element, correct the operating voltage of the magnetron, and determine that the magnetron is in an overheated state if the corrected operating voltage of the magnetron satisfies the preset conditions.

[0016] In this way, the processing circuit indirectly determines the temperature state of the magnetron via the electrical parameters of the switching element and corrects the operating voltage of the magnetron, thereby improving the control accuracy of the magnetron.

[0017] Embodiments of the present disclosure provide a heating device, the heating device comprising a drive power supply and a magnetron as described in any of the above embodiments, the magnetron being connected to the secondary coil.

[0018] In the above heating device, by detecting the electrical parameters of the switching element, it is determined that the magnetron is in an overheated state. By adjusting the electrical parameters of the switching element so that the magnetron is not in an overheated state, it is possible to avoid the magnetron operating in an overheated state for a long period of time and extend the service life of the magnetron.

[0019] Embodiments of this disclosure provide a microwave cooking device, the microwave cooking device including the heating device described in the above embodiment.

[0020] In the above-mentioned microwave cooking equipment, by detecting the electrical parameters of the switching element, it is determined that the magnetron is in an overheated state. By adjusting the electrical parameters of the switching element so that the magnetron is not in an overheated state, it is possible to avoid the magnetron operating in an overheated state for a long period of time and extend the service life of the magnetron.

[0021] Embodiments of the present disclosure provide a method for controlling a drive power supply, the drive power supply comprising a rectifier-smoothing circuit and an inverter circuit, the inverter circuit comprising a transformer and a switching element, the transformer comprising a primary coil and a secondary coil, the switching element being connected to the primary coil, the secondary coil being used to connect to a magnetron, the rectifier-smoothing circuit being used to connect to an AC power supply, the primary coil being connected to the rectifier-smoothing circuit, and the control method comprising the steps of detecting the electrical parameters of the switching element, determining that the magnetron is in an over-temperature state if the electrical parameters of the switching element satisfy a preset condition, and adjusting the electrical parameters of the switching element so that the magnetron is not in an over-temperature state.

[0022] In the above-described control method for the drive power supply, by detecting the electrical parameters of the switching element, it is determined that the magnetron is in an over-temperature state. By adjusting the electrical parameters of the switching element so that the magnetron is not in an over-temperature state, it is possible to avoid the magnetron operating in an over-temperature state for a long period of time and extend the service life of the magnetron.

[0023] In some embodiments, the control method includes the steps of determining the operating voltage of the magnetron based on the electrical parameters of the switching element and correcting the operating voltage of the magnetron, and determining that the magnetron is in an over-temperature state if the corrected operating voltage of the magnetron satisfies the preset conditions.

[0024] In this way, the control method of the drive power supply indirectly determines the temperature state of the magnetron through the electrical parameters of the switching element and corrects the operating voltage of the magnetron, thereby improving the control accuracy of the magnetron.

[0025] Additional aspects and advantages of the present disclosure will be shown in part in the following description, become apparent in part from the following description, or be understood by the implementation of the present disclosure.

Brief Description of the Drawings

[0026] The above and / or additional aspects and advantages of the present disclosure will become apparent and be readily understood from the description of the embodiments in combination with the following drawings, where

[0027] [Figure 1] FIG. 1 is a circuit diagram of a drive power supply according to an embodiment of the present disclosure. [Figure 2] FIG. 2 is another circuit diagram of a drive power supply according to an embodiment of the present disclosure. [Figure 3] FIG. 3 is an operating waveform diagram of a magnetron in a low-temperature state according to an embodiment of the present disclosure. [Figure 4] FIG. 4 is an operating waveform diagram of a magnetron in a high-temperature state according to an embodiment of the present disclosure. [Figure 5] FIG. 5 is a waveform diagram of an AC power supply according to an embodiment of the present disclosure. [Figure 6] FIG. 6 is an operating waveform diagram of an inverter circuit of a magnetron in a low-temperature state according to an embodiment of the present disclosure. [Figure 7] FIG. 7 is an operating waveform diagram of an inverter circuit of a magnetron in a high-temperature state according to an embodiment of the present disclosure. [Figure 8] FIG. 8 is a schematic flowchart of a control method for a drive power supply according to an embodiment of the present disclosure. [Figure 9] FIG. 9 is a schematic flowchart of a control method for a drive power supply according to an embodiment of the present disclosure. [Figure 10] FIG. 10 is a circuit diagram of a drive power supply according to the related art.

Embodiments for Carrying Out the Invention

[0028] The embodiments of the present disclosure are described in detail below, with examples of such embodiments shown in the drawings, where the same or similar designations throughout indicate the same or similar elements, or elements having the same or similar functions. The embodiments described below with reference to the drawings are illustrative and are used solely for illustrative purposes of the present disclosure and should not be construed as limiting the present disclosure.

[0029] In the descriptions of this disclosure, terms such as “center,” “vertical,” “horizontal,” “length,” “width,” “thickness,” “top,” “bottom,” “front,” “back,” “left,” “right,” “vertical,” “horizontal,” “top,” “bottom,” “inside,” “outside,” “clockwise,” and “counterclockwise” refer to directions or positional relationships that are merely intended to facilitate and simplify the descriptions of this disclosure, and do not indicate or imply that the indicated devices or elements have a specific direction, or should be composed of and operated in a specific direction, and should therefore not be understood as limiting this disclosure. In the descriptions of this disclosure, “multiple” means two or more unless otherwise clearly and specifically limited.

[0030] In this disclosure, unless otherwise explicitly stated or limited, the terms “attachment,” “connection,” and “connection” shall be interpreted broadly, and may include, for example, a fixed connection, a detachable connection, or an integral connection. They may be mechanical or electrical connections. They may be directly connected, indirectly connected via an intermediate medium, or be internal communication or an interaction between two elements. Those skilled in the art will understand the specific meaning of these terms in this disclosure on a case-by-case basis.

[0031] In this disclosure, unless otherwise expressly provided or limited, the phrase "above" or "below" the first feature of the second feature may include cases where the first and second features are in direct contact, or cases where they are not in direct contact but are in contact through other features between them. Furthermore, the phrase "above," "above," or "above" the first feature of the second feature may include cases where the first feature is directly above or diagonally above the second feature, or simply indicates that the horizontal altitude of the first feature is higher than that of the second feature. The phrase "below," "below," or "below" the second feature may include cases where the first feature is directly below or diagonally below the second feature, or simply indicates that the horizontal altitude of the first feature is lower than that of the second feature.

[0032] The disclosures herein provide many different embodiments or examples to realize different structures of the disclosure. To simplify the disclosures herein, parts and installations of specific examples are described herein. Of course, these are merely illustrative and are not intended to limit the disclosures herein. Furthermore, the disclosures herein may repeat reference numbers and / or reference letters in different examples, and this repetition is for simplification and clarity and does not itself indicate relationships between the various embodiments and / or installations discussed herein. Also, the disclosures herein provide examples of various specific processes and materials, but those skilled in the art will be able to recognize the application of other processes and / or the use of other materials.

[0033] In the related technology, refer to Figure 10, which is a circuit diagram of the drive power supply 400 of the related technology. As shown in Figure 10, the drive power supply 400 adds an isolated photocoupler 90 and a current sensing resistor 91, and controls the temperature of the magnetron 500 via the control circuit 70 by acquiring the current change of the magnetron 500 via the MGT current sensing module 71. Because the above proposal has many components, the structure of related microwave cooking equipment such as microwave ovens becomes complex and the cost increases.

[0034] Referring to Figures 1 to 5, the drive power supply 100 provided in the embodiments of this disclosure is used to supply power to the magnetron 200. The drive power supply 100 includes a rectifier and smoothing circuit 10, an inverter circuit 20, and a processing circuit 30.

[0035] The inverter circuit 20 includes a transformer 21 and a switching element 22. The transformer 21 includes a primary coil 211 and a secondary coil 212. The switching element 22 is connected to the primary coil 211, and the secondary coil 212 is used to connect to the magnetron 200. The rectifier and smoothing circuit 10 is used to connect to the AC power supply 300, and the primary coil 211 is connected to the rectifier and smoothing circuit 10. The processing circuit 30 is connected to the inverter circuit 20 and is used to control the on / off state of the switching element 22. The processing circuit 30 is used to detect the electrical parameters of the switching element 22, and if the electrical parameters of the switching element 22 satisfy preset conditions, it determines that the magnetron 200 is in an over-temperature state, and adjusts the electrical parameters of the switching element 22 so that the magnetron 200 is not in an over-temperature state.

[0036] Referring to Figures 1 and 2, embodiments of the present disclosure further provide a heating device 1000. The heating device 1000 includes the drive power supply 100 and the magnetron 200 in the above embodiments, the magnetron 200 being connected to the secondary coil 212.

[0037] In the above-mentioned drive power supply 100 and heating device 1000, by detecting the electrical parameters of the switching element 22, it is determined that the magnetron 200 is in an over-temperature state. By adjusting the electrical parameters of the switching element 22 so that the magnetron 200 is not in an over-temperature state, it is possible to avoid the magnetron 200 being operated in an over-temperature state for a long period of time and to extend the service life of the magnetron 200.

[0038] Specifically, in one embodiment, the rectifier-smoothing circuit 10 includes a rectifier circuit and a smoothing circuit. The rectifier circuit is mainly composed of rectifier diodes, and in one embodiment, the number of rectifier diodes may be four, forming a rectifier bridge, and in other embodiments, the number of rectifier diodes may be any other number, and no specific limitations are set here. The rectifier circuit is used to convert the voltage output from the AC power supply 300 into DC power. The smoothing circuit is connected to the rectifier circuit and the inverter circuit 20, and the smoothing circuit includes an inductor 11 and a smoothing capacitor 12, and the voltage rectified by the rectifier circuit is smoothed by the inductor 11 and the smoothing capacitor 12. The smoothing circuit is used to make the output voltage after smoothing more stable by reducing the AC voltage component of the DC power output from the rectifier circuit as much as possible and retaining the DC voltage portion.

[0039] The transformer 21 may be a step-up transformer, and is used to boost the voltage transmitted from the rectifier and smoothing circuit 10 to the inverter circuit 20 and supply power to the magnetron 200.

[0040] The magnetron 200 is used to heat food by generating microwaves and emitting high-frequency output power. The operating voltage Eb of the magnetron 200 decreases as its temperature rises.

[0041] In one embodiment, the high-frequency output power W of the magnetron 200 is kept constant. Assuming that the normal temperature range of the magnetron 200 is [25°C, 100°C], the operating voltage Eb of the magnetron 200 decreases as the temperature of the magnetron 200 rises. When the magnetron 200 is in a low temperature state, it can be interpreted that the magnetron 200 is in a room temperature state, and the temperature of the magnetron 200 is room temperature (e.g., 25°C). When the magnetron 200 is in a high temperature state, it can be interpreted that the temperature of the magnetron 200 is within the normal temperature range, for example (25°C, 100°C). When the magnetron 200 is in an overtemperature state, it can be interpreted that the temperature of the magnetron 200 exceeds the normal temperature range, for example, exceeding 100°C.

[0042] According to the formula W = Eb * Ib for the high-frequency output power W of the magnetron 200, when the magnetron 200 starts operating from a low temperature state, the operating voltage Eb of the magnetron 200 decreases as the temperature of the magnetron 200 gradually rises, and the operating current Ib of the magnetron 200 increases as the high-frequency output power W of the magnetron 200 is kept constant. The above example is for illustrative purposes only and does not limit the practical application of the embodiments of this disclosure.

[0043] Referring to Figures 3 and 4, Figure 3 shows that when the magnetron 200 is in a low-temperature state (i.e., room temperature), the operating voltage Eb is large, the waveform is high, and the high-frequency output power W of the magnetron 200 is kept constant. At this time, the operating current Ib is small, and the waveform of the operating current Ib is narrow. In contrast to Figure 3, Figure 4 shows that when the magnetron 200 is in a high-temperature state, the operating voltage Eb is small, the waveform is low, and the high-frequency output power W of the magnetron 200 is kept constant. At this time, the operating current Ib is large, and the waveform of the operating current Ib is wide.

[0044] In one embodiment, the electrical parameters of the switching element 22 and the operating voltage Eb of the magnetron 200 are positively correlated. The relationship between the electrical parameters of the switching element 22 and the operating voltage Eb of the magnetron 200 can be obtained in advance through multiple simulations and measurements. That is, when the electrical parameters of the switching element 22 are large, the operating voltage Eb of the magnetron 200 is large, and when the electrical parameters of the switching element 22 are small, the operating voltage Eb of the magnetron 200 is small.

[0045] Based on the above, there is a negative correlation between the electrical parameters of the switching element 22 and the temperature of the magnetron 200. More specifically, when the electrical parameters of the switching element 22 increase, the operating voltage Eb of the magnetron 200 increases, which in turn causes the temperature of the magnetron 200 to decrease. When the electrical parameters of the switching element 22 decrease, the operating voltage Eb of the magnetron 200 decreases, which in turn causes the temperature of the magnetron 200 to increase.

[0046] The electrical parameters of the switching element 22 may be the on-pulse width of the switching element 22, the voltage of the switching element 22, or other parameters; no specific restrictions are imposed here. As shown in Figure 1, the on-pulse width of the switching element 22 can be detected and obtained via the frequency detection circuit 33. As shown in Figure 2, the voltage of the switching element 22 can be detected and obtained via the voltage detection circuit 31.

[0047] In one embodiment, the preset conditions may be that the numerical value of an electrical parameter is smaller than the lower limit of the preset range of electrical parameters, that is, the operating voltage Eb of the magnetron 200 is smaller than the lower limit of the preset range of operating voltages, where the temperature of the corresponding magnetron 200 is greater than the upper limit of the preset temperature range, and it is determined that the magnetron 200 is in an overheated state.

[0048] If the electrical parameters of the switching element 22, acquired in real time, meet the pre-set conditions, it can be determined that the magnetron 200 is in an over-temperature state. The processing circuit 30 increases the electrical parameter values ​​of the switching element 22 so that the electrical parameter values ​​are above the lower limit of the pre-set electrical parameter range. This sets the operating voltage Eb of the magnetron 200 above the lower limit of the pre-set operating voltage range, and consequently sets the temperature of the magnetron 200 below the upper limit of the pre-set temperature range, so that the magnetron 200 is not in an over-temperature state.

[0049] In one embodiment, referring to Figure 5, which is a sine wave diagram of the AC power supply 300, the AC power supply 300 is small in the low voltage region where the voltage is near 0V and does not reach the operating voltage Eb of the magnetron 200. Therefore, the sine wave diagram of the AC power supply 300 does not show a period in which the operating current Ib of the magnetron 200 flows. The drive power supply 100 generates a resonance phenomenon in the inverter circuit 20 by conducting and / or interrupting the switching element 22, causing the voltage of the primary coil 211 of the transformer 21 to rise, which induces the secondary coil 212 of the transformer 21 to generate a high voltage. That is, the transformer 21 of the inverter circuit 20 boosts the AC power supply 300, and the boosted voltage can reach the operating voltage Eb of the magnetron 200, thereby driving the magnetron 200 to operate.

[0050] In one embodiment, the inverter circuit 20 further includes a resonant capacitor 23, and the resonant capacitor 23 and the primary coil 211 are formed in a resonant circuit. The switching element 22 may be a transistor, and when the switching element 22 conducts, current flows to the primary coil 211 of the transformer 21. When the switching element 22 is interrupted, the primary coil 211 of the transformer 21 releases the stored energy to the resonant capacitor 23, forming a resonance phenomenon.

[0051] In one embodiment, the drive power supply 100 further includes a high-voltage rectifier circuit 40. The high-voltage rectifier circuit 40 is connected to the secondary coil 212 and the magnetron 200 of the transformer 21 and is used to rectify and smooth the boosted voltage of the secondary coil 212 and drive the magnetron 200 to operate.

[0052] In some embodiments, the electrical parameters of the switching element 22 include the voltage of the switching element 22.

[0053] In this way, the drive power supply 100 can determine the temperature state of the magnetron 200 by observing the voltage of the switching element 22 via the voltage detection circuit 31 and determining the magnitude of the operating voltage Eb of the magnetron 200.

[0054] Specifically, if the electrical parameter of the switching element 22 is the voltage of the switching element 22, the voltage of the switching element 22 can be detected and obtained via the voltage detection circuit 31.

[0055] In one embodiment, the switching element 22 is a transistor, and the voltage at the collector C of the transistor and the voltage at the primary coil 211 of the transformer 21 are positively correlated. Furthermore, as the temperature of the magnetron 200 rises, the operating voltage Eb of the magnetron 200 decreases, and the voltage at the collector C decreases. That is, the drive power supply 100 can determine whether the magnetron 200 is in an overheated state by observing the voltage value at the collector C via the voltage detection circuit 31 and determining the magnitude of the operating voltage Eb of the magnetron 200.

[0056] In more detail, if the electrical parameter of the switching element 22 is the voltage value of the collector C, the lower limit of the preset voltage range of the collector C is 180V, the lower limit of the preset operating voltage range of the magnetron 200 is 90V, and the upper limit of the preset temperature range of the magnetron 200 is 120°C. If the current voltage of the collector C is observed to be less than 180V, that is, if the operating voltage Eb of the magnetron 200 is less than 90V, the temperature of the magnetron 200 exceeds 120°C, and at this time it is determined that the magnetron 200 is in an over-temperature state. The processing circuit 30 increases the voltage of the collector C of the switching element 22 so that the voltage of the collector C becomes equal to or above the lower limit of the preset voltage range, thereby setting the operating voltage Eb of the magnetron 200 to equal to or above the lower limit of the preset operating voltage range, and consequently the temperature of the magnetron 200 decreases, ensuring that the magnetron 200 is not in an over-temperature state. The above example is for illustrative purposes only and does not limit the actual application of the embodiments of this disclosure.

[0057] Referring to Figure 2, in some embodiments, the switching element 22 includes a transistor, the transistor includes a collector C, the voltage of the switching element 22 includes the voltage of the collector C, the processing circuit 30 includes a voltage detection circuit 31 and an arithmetic circuit 32, the arithmetic circuit 32 is connected to the voltage detection circuit 31, the voltage detection circuit 31 is connected to the collector C, the voltage detection circuit 31 is used to detect the voltage of the collector C, the arithmetic circuit 32 determines that the magnetron 200 is in an over-temperature state if the voltage of the collector C satisfies a preset condition, and is used to adjust the voltage of the collector C so that the magnetron 200 is in a non-over-temperature state.

[0058] In this way, the arithmetic circuit 32 determines that the magnetron 200 is in an overheated state via the voltage of the collector C of the switching element 22, and adjusts the voltage of the collector C to ensure the normal operation of the magnetron 200.

[0059] Specifically, the voltage detection circuit 31 is connected to the collector C of the switching element 22 and the arithmetic circuit 32, and is used to detect and acquire the voltage data of the collector C and transmit it to the arithmetic circuit 32.

[0060] In one embodiment, the processing circuit 30 further includes a power supply voltage detection circuit 34. The power supply voltage detection circuit 34 is used to ensure the normal operation of the drive power supply 100 by detecting voltage data of the AC power supply 300 and transmitting it to the calculation circuit 32.

[0061] If the voltage of the collector C of the switching element 22 satisfies the preset conditions, for example, the lower limit of the preset voltage range of collector C is 180V, the lower limit of the preset operating voltage range of magnetron 200 is 90V, and the upper limit of the preset temperature range of magnetron 200 is 120°C. When the voltage detection circuit 31 detects that the current voltage value of collector C is 170V, the operating voltage Eb of magnetron 200 is 80V and the temperature value of magnetron 200 is 130°C. That is, if the voltage value of collector C is less than the lower limit of the preset voltage range of collector C, and the operating voltage Eb of magnetron 200 is less than the lower limit of the preset operating voltage range of magnetron 200, the temperature value of magnetron 200 is greater than the upper limit of the preset temperature range of magnetron 200, and in this case it is determined that magnetron 200 is in an overheated state. The above example is for illustrative purposes only and does not limit the actual application of the embodiments of this disclosure.

[0062] The processing circuit 30 can adjust the temperature state of the magnetron 200 by observing and adjusting the voltage value of the collector C of the switching element 22, thereby reducing the prolonged high-temperature operation process of the magnetron 200. Specifically, if it is determined that the magnetron 200 is in an over-temperature state, the processing circuit 30 controls the switching element 22 to shut off via the calculation circuit 32, which increases the resonant voltage generated by the inverter circuit 20, increases the voltage of the collector C, induces an increase in the voltage of the secondary coil 212 of the transformer 21, and consequently increases the operating voltage Eb of the magnetron 200 so that the magnetron 200 is not in an over-temperature state.

[0063] In one embodiment, the relationship between the voltage of the collector C of the switching element 22, the operating voltage Eb of the magnetron 200, and the temperature of the magnetron 200 can be acquired in advance through multiple simulations and measurements and stored in the calculation circuit 32. That is, the drive power supply 100 can acquire a measurement data set of the voltage of the collector C, the operating voltage Eb of the magnetron 200, and the temperature of the magnetron 200 through multiple data measurements, and the values ​​of the voltage of the collector C, the operating voltage Eb of the magnetron 200, and the temperature of the magnetron 200 correspond one-to-one, making it easy to quickly determine whether the magnetron 200 is in an over-temperature state through the measurement data set.

[0064] Referring to Figures 6 and 7, in some embodiments, the electrical parameters of the switching element 22 include the on-pulse width of the switching element 22.

[0065] In this way, the drive power supply 100 can determine the temperature state of the magnetron 200 by observing the on-pulse width of the switching element 22 via the frequency detection circuit 33 and determining the magnitude of the operating voltage Eb of the magnetron 200.

[0066] Specifically, in one embodiment, if the electrical parameter of the switching element 22 is the on-pulse width of the switching element 22, the on-pulse width can be detected and obtained via the frequency detection circuit 33.

[0067] In one embodiment, as shown in Figure 6, Figure 6 is a schematic diagram of the current at the collector C of the switching element 22 and the voltage at the primary coil 211 of the transformer 21 when the magnetron 200 is in a low temperature state (i.e., room temperature state). According to the properties of the magnetron, when the magnetron 200 is in a low temperature state (i.e., room temperature state), the operating voltage Eb of the magnetron 200 is large. As shown in Figure 6, when the magnetron 200 is in a low temperature state (i.e., room temperature state), the voltage at the primary coil 211 of the transformer 21 is large, and the resonant voltage generated by the inverter circuit 20 is large, which causes the voltage waveform of the primary coil 211 of the transformer 21 to be high, and the on-pulse width of the switching element 22 becomes wider. As the temperature of the magnetron 200 rises, the operating voltage Eb of the magnetron 200 decreases, and the on-pulse width of the switching element 22 becomes narrower.

[0068] In another embodiment, as shown in Figure 7, Figure 7 is a schematic diagram of the current at the collector C of the switching element 22 and the voltage at the primary coil 211 of the transformer 21 when the magnetron 200 is in a high-temperature state. According to the properties of the magnetron, when the magnetron 200 is in a high-temperature state, the operating voltage Eb of the magnetron 200 is small. As shown in Figure 7, when the magnetron 200 is in a high-temperature state, the voltage at the primary coil 211 of the transformer 21 is small, the resonant voltage generated by the inverter circuit 20 is small, and as a result the voltage waveform of the primary coil 211 of the transformer 21 becomes low, and the on-pulse width of the switching element 22 becomes narrow. That is, the drive power supply 100 can determine whether the magnetron 200 is in an over-temperature state by observing the width of the on-pulse width of the switching element 22 via the frequency detection circuit 33 and determining the magnitude of the operating voltage Eb of the magnetron 200.

[0069] In detail, if the electrical parameter of the switching element 22 is the on-pulse width, the lower limit of the preset on-pulse width range of the switching element 22 is p, the lower limit of the preset operating voltage range of the magnetron 200 is 90V, and the upper limit of the preset temperature range of the magnetron 200 is 120°C. If the current on-pulse width value is observed to be less than p, that is, if the operating voltage Eb of the magnetron 200 is less than 90V, the temperature of the magnetron 200 exceeds 120°C, and at this time it is determined that the magnetron 200 is in an over-temperature state. The processing circuit 30 increases the on-pulse width of the switching element 22 so that the on-pulse width becomes equal to or greater than the lower limit of the preset on-pulse width range, thereby setting the operating voltage Eb of the magnetron 200 to equal or greater than the lower limit of the preset operating voltage range, and consequently the temperature of the magnetron 200 decreases, ensuring that the magnetron 200 is not in an over-temperature state. The above example is for illustrative purposes only and does not limit the actual application of the embodiments of this disclosure.

[0070] Referring to Figure 1, in some embodiments, the processing circuit 30 includes a frequency detection circuit 33 and an arithmetic circuit 32, the arithmetic circuit 32 is connected to the frequency detection circuit 33, the frequency detection circuit 33 is connected to the switching element 22, the frequency detection circuit 33 is used to detect the on-pulse width of the switching element 22, the arithmetic circuit 32 determines that the magnetron 200 is in an over-temperature state if the on-pulse width of the switching element 22 satisfies a preset condition, and is used to adjust the on-pulse width of the switching element 22 so that the magnetron 200 is not in an over-temperature state.

[0071] In this way, the calculation circuit 32 determines that the magnetron 200 is in an overheated state via the on-pulse width of the switching element 22, and adjusts the on-pulse width of the switching element 22 to ensure the normal operation of the magnetron 200.

[0072] Specifically, the frequency detection circuit 33 is connected to the collector C of the switching element 22 and the arithmetic circuit 32, and is used to detect and acquire the on-pulse width of the switching element 22 and transmit it to the arithmetic circuit 32.

[0073] When the on-pulse width of the switching element 22 satisfies preset conditions, for example, the lower limit of the preset on-pulse width range is p, the lower limit of the preset operating voltage range of the magnetron 200 is 90V, and the upper limit of the preset temperature range of the magnetron 200 is 120°C. When the frequency detection circuit 33 detects that the current on-pulse width is p, the operating voltage Eb of the magnetron 200 is 80V and the temperature value of the magnetron 200 is 130°C. That is, when the on-pulse width is smaller than the lower limit of the preset on-pulse width range and the operating voltage Eb of the magnetron 200 is smaller than the lower limit of the preset operating voltage range of the magnetron 200, the temperature value of the magnetron 200 is larger than the upper limit of the preset temperature range of the magnetron 200, and in this case it is determined that the magnetron 200 is in an over-temperature state. The above example is for illustrative purposes only and does not limit the actual application of the embodiments of this disclosure.

[0074] The processing circuit 30 can adjust the temperature state of the magnetron 200 by observing and adjusting the on-pulse width of the switching element 22, thereby reducing the prolonged high-temperature operation process of the magnetron 200. Specifically, if it is determined that the magnetron 200 is in an over-temperature state, the processing circuit 30 controls the switching element 22 to shut off via the calculation circuit 32, which increases the resonant voltage generated by the inverter circuit 20 and widens the on-pulse width of the switching element 22, inducing an increase in the voltage of the secondary coil 212 of the transformer 21, and consequently increasing the operating voltage Eb of the magnetron 200 so that the magnetron 200 is in a non-over-temperature state.

[0075] In one embodiment, the relationship between the on-pulse width of the switching element 22, the operating voltage Eb of the magnetron 200, and the temperature of the magnetron 200 can be acquired in advance through multiple simulations and measurements and stored in the calculation circuit 32. That is, the drive power supply 100 can acquire a measurement data set of the on-pulse width of the switching element 22, the operating voltage Eb of the magnetron 200, and the temperature of the magnetron 200 through multiple data measurements, and the on-pulse width of the switching element 22, the numerical value of the operating voltage Eb of the magnetron 200, and the numerical value of the temperature of the magnetron 200 correspond one-to-one, making it easy to quickly determine whether the magnetron 200 is in an over-temperature state through the measurement data set.

[0076] Referring to Figures 1 and 2, in some embodiments, the processing circuit 30 determines the operating voltage Eb of the magnetron 200 based on the electrical parameters of the switching element 22, corrects the operating voltage Eb of the magnetron 200, and determines that the magnetron 200 is in an overtemperature state if the corrected operating voltage Eb of the magnetron 200 satisfies a preset condition.

[0077] In this way, the processing circuit 30 indirectly determines the temperature state of the magnetron 200 via the electrical parameters of the switching element 22 and corrects the operating voltage Eb of the magnetron 200, thereby improving the control accuracy of the magnetron 200.

[0078] Specifically, in one embodiment, the embodiment of the present disclosure can ensure the normal operation of the magnetron 200 by determining the standard range of the electrical parameters of the switching element 22 in advance through data from multiple simulations and measurements, and storing it in the calculation circuit 32 in the form of a computer program.

[0079] The pre-set conditions may include the operating voltage Eb of the magnetron 200 being less than the lower limit of the pre-set operating voltage range, for example, 90V, and it can be determined that the magnetron 200 is in an overheated state. Specifically, if the operating voltage Eb of the magnetron 200 is less than 90V, that is, if the operating voltage Eb of the magnetron 200 is less than the lower limit of the pre-set operating voltage range, the temperature value of the magnetron 200 is greater than the upper limit of the pre-set temperature range, and in this case, it is determined that the magnetron 200 is in an overheated state.

[0080] The operating voltage Eb of the magnetron 200 has a 10% deviation between its upper and lower voltage limits when it is in a low-temperature state (i.e., room temperature state). Because of this deviation, the operating voltage Eb of the magnetron 200, which is directly determined by the electrical parameters of the switching element 22 (e.g., the voltage of collector C), has a deviation from the actual operating voltage of the magnetron 200. As a result, the temperature state of the magnetron 200 cannot be accurately determined.

[0081] In this embodiment, the operating voltage Eb of the magnetron 200 is determined based on the electrical parameters of the switching element 22, and the operating voltage Eb of the magnetron 200 is corrected. If the corrected operating voltage Eb of the magnetron 200 satisfies a preset condition, it is determined that the magnetron 200 is in an over-temperature state. This makes the judgment regarding the temperature state of the magnetron 200 more accurate and improves the control accuracy of the magnetron 200.

[0082] For example, the deviation value can be removed by correcting the 10% deviation value mentioned above. Once the corrected operating voltage Eb of the magnetron 200 is closer to the actual operating voltage of the magnetron 200, the control of the magnetron 200 becomes more accurate by comparing the corrected operating voltage Eb with a preset condition.

[0083] Similarly, the method for determining the on-pulse width of the switching element 22 is similar to the method for determining the voltage of collector C, and to avoid duplication, a detailed explanation is omitted here.

[0084] The calculation circuit 32 determines the operating voltage Eb of the magnetron 200 based on the electrical parameters of the switching element 22, which are monitored in real time. If the corrected operating voltage Eb of the magnetron 200 is smaller than the lower limit of a preset operating voltage range, it determines that the magnetron 200 is in an over-temperature state.

[0085] Embodiments of this disclosure provide microwave cooking equipment, which includes the heating device 1000 of the above embodiment.

[0086] In the above-mentioned microwave cooking equipment, by detecting the electrical parameters of the switching element 22, it is determined that the magnetron 200 is in an overheated state. By adjusting the electrical parameters of the switching element 22 so that the magnetron 200 is not in an overheated state, it is possible to avoid the magnetron 200 operating in an overheated state for a long period of time and extend the service life of the magnetron 200.

[0087] The above description of the embodiment of the heating device 1000 and its beneficial effects also applies to the microwave cooking equipment of the embodiment of this disclosure, and to avoid duplication, a detailed explanation is omitted here.

[0088] In one embodiment, microwave cooking equipment includes, but is not limited to, home appliances such as microwave ovens, microwave steam ovens, and microwave rice cookers.

[0089] Referring to Figure 8, an embodiment of the present disclosure provides a control method for a drive power supply 100, the drive power supply 100 including a rectifier-smoothing circuit 10 and an inverter circuit 20. The inverter circuit 20 includes a transformer 21 and a switching element 22, the transformer 21 including a primary coil 211 and a secondary coil 212, the switching element 22 being connected to the primary coil 211 and the secondary coil 212 being used to connect to a magnetron 200. The rectifier-smoothing circuit 10 is used to connect to an AC power supply 300, and the primary coil 211 is connected to the rectifier-smoothing circuit 10. The control method includes a step 01 of detecting the electrical parameters of the switching element 22, and a step 03 of determining that the magnetron 200 is in an over-temperature state if the electrical parameters of the switching element 22 satisfy a preset condition, and adjusting the electrical parameters of the switching element 22 so that the magnetron 200 is not in an over-temperature state.

[0090] In the control method for the drive power supply 100 described above, by detecting the electrical parameters of the switching element 22, it is determined that the magnetron 200 is in an over-temperature state. By adjusting the electrical parameters of the switching element 22 so that the magnetron 200 is not in an over-temperature state, it is possible to avoid the magnetron 200 being operated in an over-temperature state for a long period of time and to extend the service life of the magnetron 200.

[0091] Specifically, in one embodiment, the electrical parameter of the switching element 22 may be the on-pulse width of the switching element 22, the voltage value of the collector C of the switching element 22, or other parameters, and no specific limitations are imposed here. As shown in Figure 1, the on-pulse width of the switching element 22 can be detected and obtained via the frequency detection circuit 33. As shown in Figure 2, the voltage value of the collector C of the switching element 22 can be detected and obtained via the voltage detection circuit 31.

[0092] In one embodiment, the preset condition may be that the numerical value of the electrical parameter is smaller than the lower limit of the preset range of the electrical parameter of the switching element 22, that is, the operating voltage Eb of the magnetron 200 is smaller than the lower limit of the preset range of the operating voltage, where the temperature of the corresponding magnetron 200 is greater than the upper limit of the preset range of the temperature. If the electrical parameter of the switching element 22 acquired in real time satisfies the preset condition, it can be determined that the magnetron 200 is in an over-temperature state. The processing circuit 30 can extend the service life of the magnetron 200 by increasing the numerical value of the electrical parameter of the switching element 22 and bringing the magnetron 200 into a non-over-temperature state.

[0093] Referring to Figure 9, in some embodiments, the control method includes step 031 of determining the operating voltage Eb of the magnetron 200 based on the electrical parameters of the switching element 22 and correcting the operating voltage Eb of the magnetron 200, and step 033 of determining that the magnetron 200 is in an overtemperature state if the corrected operating voltage Eb of the magnetron 200 satisfies a preset condition.

[0094] In this way, the control method of the drive power supply 100 improves the control accuracy of the magnetron 200 by indirectly determining the temperature state of the magnetron 200 via the electrical parameters of the switching element 22 and correcting the operating voltage Eb of the magnetron 200.

[0095] Specifically, in one embodiment, the embodiment of the present disclosure can guarantee the normal operation of the magnetron 200 by determining the standard range of the electrical parameters of the switching element 22 through data from multiple simulations and measurements in advance, and storing it in the calculation circuit 32 in the form of a computer program.

[0096] The pre-set conditions may include the operating voltage Eb of the magnetron 200 being less than the lower limit of the pre-set operating voltage range, for example, 90V, and it is determined that the magnetron 200 is in an overheated state. Specifically, if the operating voltage Eb of the magnetron 200 is less than 90V, that is, if the operating voltage Eb of the magnetron 200 is less than the lower limit of the pre-set operating voltage range, the temperature of the magnetron 200 is greater than the upper limit of the pre-set temperature range, and in this case, it is determined that the magnetron 200 is in an overheated state.

[0097] The operating voltage Eb of the magnetron 200 has a 10% deviation between its upper and lower voltage limits when it is in a low-temperature state (i.e., room temperature state). Because of this deviation, the operating voltage Eb of the magnetron 200, which is directly determined by the electrical parameters of the switching element 22 (e.g., the voltage of collector C), has a deviation from the actual operating voltage of the magnetron 200. As a result, the temperature state of the magnetron 200 cannot be accurately determined.

[0098] In this embodiment, the operating voltage Eb of the magnetron 200 is determined based on the electrical parameters of the switching element 22, and the operating voltage Eb of the magnetron 200 is corrected. If the corrected operating voltage Eb of the magnetron 200 satisfies a preset condition, it is determined that the magnetron 200 is in an over-temperature state. This makes the judgment regarding the temperature state of the magnetron 200 more accurate and improves the control accuracy of the magnetron 200.

[0099] For example, the deviation value can be removed by correcting the 10% deviation value mentioned above. Once the corrected operating voltage Eb of the magnetron 200 is closer to the actual operating voltage of the magnetron 200, the control of the magnetron 200 becomes more accurate by comparing the corrected operating voltage Eb with a preset condition.

[0100] Similarly, the method for determining the on-pulse width of the switching element 22 is similar to the method for determining the voltage of collector C, and to avoid duplication, a detailed explanation is omitted here.

[0101] The calculation circuit 32 determines the operating voltage Eb of the magnetron 200 based on the electrical parameters of the switching element 22, which are monitored in real time. If the corrected operating voltage Eb of the magnetron 200 is smaller than the lower limit of a preset operating voltage range, it determines that the magnetron 200 is in an over-temperature state.

[0102] In this specification, any reference to terms such as “one embodiment,” “several embodiments,” “exemplary embodiment,” “example,” “specific example,” or “several examples” means that the specific features, structures, materials, or properties described in the embodiment or example are included in at least one embodiment or example of this disclosure. The exemplary expressions of the above terms in this specification do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or properties described may be combined in an appropriate manner in any one or more embodiments or examples.

[0103] While embodiments of the present disclosure have been shown and described, those skilled in the art will understand that various changes, modifications, substitutions, and variations can be made to these embodiments without departing from the principles and spirit of the present disclosure, and the scope of the present disclosure is limited by the claims and their equivalents. [Explanation of Symbols]

[0104] 100 Power supply 200 Magnetron 300 AC power supply 10 Rectifier smoothing circuit 20 Inverter Circuit 30 Processing Circuits 40 High-voltage rectifier circuit 11 Inductance 12 Smoothing Capacitors 21 Transformer 22 Switching mechanism 23 Resonant Capacitor 31 Voltage detection circuit 32 Arithmetic circuit 33 Frequency detection circuit 34 Power supply voltage detection circuit 211 Primary coil 212 Secondary coil 1000 heating equipment

Claims

1. A power supply for supplying power to a magnetron, The drive power supply includes a rectifier and smoothing circuit, an inverter circuit, and a processing circuit. The inverter circuit includes a transformer and a switching element, The transformer includes a primary coil and a secondary coil, The switching element is connected to the primary coil, The secondary coil is used to connect to the magnetron. The rectifier-smoothing circuit is used to connect to an AC power supply. The primary coil is connected to the rectifier and smoothing circuit. The processing circuit is connected to the inverter circuit and used to control the on / off state of the switching element. The aforementioned processing circuit is To detect the electrical parameters of the switching element, A drive power supply used for determining that the magnetron is in an overtemperature state when the electrical parameters of the switching element satisfy a preset condition, and adjusting the electrical parameters of the switching element so that the magnetron is not in an overtemperature state.

2. The drive power supply according to claim 1, wherein the electrical parameters of the switching element include the voltage of the switching element.

3. The switching element includes a transistor, The aforementioned transistor includes a collector, The voltage of the switching element includes the voltage of the collector. The processing circuit includes a voltage detection circuit and a calculation circuit. The calculation circuit is connected to the voltage detection circuit, The voltage detection circuit is connected to the collector, The voltage detection circuit is used to detect the voltage of the collector. The drive power supply according to claim 2, wherein the calculation circuit determines that the magnetron is in an overtemperature state when the collector voltage satisfies the preset conditions, and is used to adjust the collector voltage so that the magnetron is not in an overtemperature state.

4. The drive power supply according to claim 1, wherein the electrical parameters of the switching element include the on-pulse width of the switching element.

5. The processing circuit includes a frequency detection circuit and an arithmetic circuit. The calculation circuit is connected to the frequency detection circuit, The frequency detection circuit is connected to the switching element, The frequency detection circuit is used to detect the on-pulse width of the switching element. The drive power supply according to claim 4, wherein the calculation circuit determines that the magnetron is in an over-temperature state when the on-pulse width of the switching element satisfies the preset conditions, and is used to adjust the on-pulse width of the switching element so that the magnetron is not in an over-temperature state.

6. The drive power supply according to claim 1, wherein the processing circuit is used to determine the operating voltage of the magnetron based on the electrical parameters of the switching element, correct the operating voltage of the magnetron, and determine that the magnetron is in an over-temperature state if the corrected operating voltage of the magnetron satisfies the preset conditions.

7. A heating device comprising a drive power supply and a magnetron according to any one of claims 1 to 6, wherein the magnetron is connected to the secondary coil.

8. A microwave cooking apparatus comprising the heating device described in claim 7.

9. A method for controlling the drive power supply, The aforementioned power supply includes a rectifier and smoothing circuit and an inverter circuit. The inverter circuit includes a transformer and a switching element. The transformer includes a primary coil and a secondary coil. The switching element is connected to the primary coil, The aforementioned secondary coil is used to connect to the magnetron. The rectifier and smoothing circuit is used to connect to an AC power supply. The primary coil is connected to the rectifier and smoothing circuit. The control method described above is The steps include detecting the electrical parameters of the switching element, A method for controlling a drive power supply, comprising the steps of: determining that the magnetron is in an over-temperature state if the electrical parameters of the switching element satisfy a preset condition, and adjusting the electrical parameters of the switching element so that the magnetron is not in an over-temperature state.

10. The steps include determining the operating voltage of the magnetron based on the electrical parameters of the switching element and correcting the operating voltage of the magnetron, The control method according to claim 9, comprising the step of determining that the magnetron is in an overheated state if the corrected operating voltage of the magnetron satisfies the preset conditions.

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