CN215378781U - Microwave soft switch variable frequency power supply - Google Patents
Microwave soft switch variable frequency power supply Download PDFInfo
- Publication number
- CN215378781U CN215378781U CN202121782069.6U CN202121782069U CN215378781U CN 215378781 U CN215378781 U CN 215378781U CN 202121782069 U CN202121782069 U CN 202121782069U CN 215378781 U CN215378781 U CN 215378781U
- Authority
- CN
- China
- Prior art keywords
- power supply
- circuit
- capacitor
- transformer
- igbt module
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
Images
Landscapes
- Dc-Dc Converters (AREA)
Abstract
The utility model discloses a microwave soft switch variable frequency power supply, which comprises a full-bridge rectifier filter, a half-bridge switch network, a drive control circuit and a transformer, wherein the full-bridge rectifier filter is connected with the half-bridge switch network; the half-bridge switch network comprises two IGBT modules, a capacitor C3 is connected in parallel between a drain D and a source S of the IGBT module Q1, and a capacitor C2 is connected in series between a drain D of the IGBT module Q1 and the input end of a primary coil of a transformer; a capacitor C7 is connected in series between the source S of the IGBT module Q2 and the input end of the primary coil of the transformer. The soft switching variable frequency power supply topology structure is a soft switching variable frequency power supply topology structure formed by a full-bridge rectifier filter, a half-bridge switching network, an LCC resonant network, a transformer and the like, the voltage output by the power supply is controlled by the switching frequency output by a power supply controller, and meanwhile, the loss of an IGBT module is very small due to the existence of the LCC resonant network; meanwhile, the switching frequency is changed by driving the control circuit, so that the output voltage is changed, and the power of the microwave energy generated by the magnetron is finally controlled.
Description
Technical Field
The utility model relates to a microwave power supply unit, in particular to a microwave soft-switching variable-frequency power supply.
Background
The majority of the components of the human body are carbohydrates, the molecules of the carbohydrates are polar molecules, the polarity of the polar molecules is changed along with the microwave frequency under the action of a microwave field, the polar oscillation is called as polar oscillation, the frequency of the polar oscillation is the same as the microwave frequency, and the amplitude of the polar oscillation is in direct proportion to the microwave intensity.
The principle of microwave treatment of diseases is complex, and the research results at home and abroad show that the microwave treatment of diseases is mainly realized through thermal effect and biological effect. Because the magnetic resistance exists between the polar molecules to generate damping action on oscillation, the microwave energy is consumed to generate heat, and the aim of treating diseases is achieved by utilizing the heat, namely the heat effect of microwave treatment. Researches and experiments show that the treatment effect of the microwave-assisted hot compress far exceeds that of other hot compress methods when the microwave is used for irradiating the pathological change part.
The biological electromagnetism technology is used as a very active new technical field in electromagnetism, and is developed rapidly in recent decades, the more the treatment is carried out by utilizing the pyrogenicity effect of the microwave in clinical application, however, the microwave power is not easy to control and is easy to be influenced by factors such as power grid voltage fluctuation and load traction, and the microwave power is out of control.
The core device of the microwave energy is a magnetron, the magnetron is a high-voltage electric device, and an external power converter is needed, so the efficiency of a magnetron power supply has great influence on the efficiency of the microwave energy, the power supply quality of the magnetron power supply also influences the working state of the magnetron, the high-quality power supply can also improve the microwave efficiency of the magnetron, and the high-voltage power supply is needed, so that the loss is high, the microwave power supply is damaged, the output of the microwave energy is influenced, and the treatment efficiency of the microwave energy is finally influenced. At present, most microwave energy power supplies use voltage regulating blocks to regulate voltage or linear power supplies to supply power, and the power supplies have large volume and weight, low efficiency, low power density and large loss due to a plurality of discrete elements.
Patent CN200410024251.X discloses a magnetron working power supply of a microwave oven, which comprises a power frequency rectifier filter (A) circuit capable of rectifying alternating current commercial power into direct current; a power supply converter (B) connected with the power frequency rectifier filter (A) and composed of a power frequency rectifier filter circuit for providing working power supply and a high-frequency switch circuit for converting the direct current output by the power frequency rectifier filter into high-frequency high-voltage electricity; a high-frequency rectifier filter (C) circuit connected with the output end of the power converter (B) circuit for rectifying the high-frequency high-voltage electricity output by the power converter circuit into direct-current high-voltage electricity, and a magnetron filament power supply.
The power converter (B) is composed of a high-power transistor switch tube and an inductance coil, and the inductance coil is provided with a secondary winding which is connected with a filament of a magnetron (E) to form a filament power supply (D).
At present, most of power supplies of microwave energy adopt a scheme of boosting by a power frequency transformer and then rectifying. The power supply mode not only ensures that the microwave oven has high energy consumption, large volume and heavy weight, but also has unadjustable output power, and the safety and the stability of the power supply can not be well controlled, thereby directly influencing the treatment effect of the microwave energy.
SUMMERY OF THE UTILITY MODEL
The utility model aims to provide a microwave soft-switching variable-frequency power supply.
In order to achieve the above object, an embodiment of the present invention provides a microwave soft-switching variable frequency power supply, including:
a full bridge rectifier filter; the system is used for being connected with the three-phase alternating current of the commercial power, rectifying and filtering the input commercial power and outputting direct current;
a half-bridge switching network; the input end of the half-bridge switch network is connected with the output end of the full-bridge rectifier filter to process and control the input direct current; the half-bridge switch network comprises two IGBT modules, namely an IGBT module Q1 and an IGBT module Q2;
a capacitor C3 is connected in parallel between the drain D and the source S of the IGBT module Q1, and a capacitor C2 is connected in series between the drain D of the IGBT module Q1 and the input end of the primary coil of the transformer;
a capacitor C7 is connected in series between the source S of the IGBT module Q2 and the input end of the primary coil of the transformer;
a power supply controller; the power controller is provided with a driving control circuit, and the driving control circuit is connected with a grid G of the IGBT module and is used for controlling the on-off states of the IGBT module Q1 and the IGBT module Q2;
a transformer; the transformer transforms the input alternating current and comprises two secondary coils, namely a low-voltage secondary coil and a high-voltage secondary coil;
the output end of the low-voltage secondary coil of the transformer is connected with the low-voltage rectification filtering module;
the output end of the high-voltage secondary coil of the transformer is connected with the high-voltage rectification filter module.
In an optimized scheme of the utility model, a full-bridge rectifier filter is provided, and the full-bridge rectifier filter comprises a rectifier circuit D10 and a first LC filter circuit, wherein the first LC filter circuit comprises an inductor L1 and a capacitor C6; both ends of the capacitor C6 are connected to the drain D of the IGBT module Q1 and the source S of the IGBT module Q2, respectively.
In one of the optimization schemes of the utility model, in order to detect each path of current signal, the input end of the power supply controller is preferably connected with the output end of the full-bridge rectifier filter, the output end of the IGBT module and the output end of the transformer for collecting the current signal.
In one of the optimization schemes of the utility model, the transformer is provided with a tap, and the low-voltage secondary coil is connected with the tap.
In one of the optimization schemes of the utility model, the low-voltage rectification filter module comprises a rectification circuit D2, a rectification circuit D4 and a second LC filter circuit; the input ends of the rectifying circuit D2 and the rectifying circuit D4 are respectively connected to different taps of a low-voltage secondary coil of the transformer;
the second LC filter circuit comprises an inductor L2 and a capacitor C4, the output ends of the rectifying circuit D2 and the rectifying circuit D4 are connected with an inductor L2 of the second LC filter circuit, and an inductor C4 is connected between the high-voltage output end and the low-voltage output end.
In one of the optimization schemes of the utility model, the high-voltage rectification filter module comprises a rectification circuit D9, a rectification circuit D8, a rectification circuit D6 and a rectification circuit D11; a capacitor C9 and a capacitor C8 are arranged between the output end of the rectifying circuit D9 and the rectifying circuit D8 and between the output end of the rectifying circuit D6 and the rectifying circuit D11, and a resistor R3 is connected in parallel to the capacitor C9 and the capacitor C8.
In one of the optimization schemes of the utility model, the drive control circuit is a PWM drive control circuit.
In summary, the utility model has the following advantages:
1. the soft switching variable frequency power supply topology structure is a soft switching variable frequency power supply topology structure formed by a full-bridge rectifier filter, a half-bridge switching network, an LCC resonant network, a transformer and the like, the voltage output by the power supply is controlled by the switching frequency output by a power supply controller, and meanwhile, the loss of an IGBT module is very small due to the existence of the LCC resonant network; meanwhile, the switching frequency is changed by driving the control circuit, so that the output voltage is changed, and the power of the microwave energy generated by the magnetron is finally controlled.
2. The utility model has the working characteristics of the resonant converter, the output end adopts the resonant soft switching converter in a voltage-doubling rectification mode as a power supply of the load, the power supply has smaller volume, smaller weight and higher power density, the harmonic pollution to a power grid can be reduced, and the continuous adjustment of the output power can be realized.
3. The utility model can provide continuously adjustable power supply voltage for the load of the magnetron, can reduce the volume and the weight of the power supply while improving the microwave energy efficiency, and can prolong the service life of the magnetron because the frequent starting and stopping of the magnetron are avoided. In addition, the output power of the microwave energy can be conveniently adjusted by adopting the power supply of the switching power supply, so that the clinical treatment effect of the microwave energy is safer and more effective.
Drawings
FIG. 1 is a circuit diagram of a microwave soft-switching variable frequency power supply in one embodiment of the present invention;
fig. 2 is a schematic block diagram of a microwave soft-switching variable frequency power supply in an embodiment of the present invention.
Detailed Description
The utility model provides a microwave soft switching variable frequency power supply which comprises a full-bridge rectifier filter, a half-bridge switching network, a power supply controller and a transformer.
The full-bridge rectifier filter is used for being connected with the three-phase alternating current of the commercial power, carrying out rectification filtering processing on the input commercial power and outputting direct current.
The full-bridge rectifier filter comprises a rectifier circuit D10 and a first LC filter circuit, wherein the first LC filter circuit comprises an inductor L1 and a capacitor C6; both ends of the capacitor C6 are connected to the drain D of the IGBT module Q1 and the source S of the IGBT module Q2, respectively. The commercial power is rectified on a rectifying bridge formed by the commercial power input rectifying circuit D10, and the direct-current voltage obtained by further filtering is used as the input voltage of the half-bridge switching network through a first LC filter circuit formed by an inductor L1 and a capacitor C6.
The input end of the half-bridge switch network is connected with the output end of the full-bridge rectifier filter to process and control the input direct current; the half-bridge switching network includes two IGBT modules, IGBT module Q1 and IGBT module Q2, respectively.
The gates of the IGBT module Q1 and the IGBT module Q2 are connected to a drive control signal, and the drive control circuit is preferably a PWM drive control circuit. The PWM drive control circuit controls the IGBT module Q1, and the IGBT module Q2 to turn on and off.
Because the IGBT module is not an ideal device, turn-off delay and turn-on delay exist, generally, the turn-off delay is longer than the turn-on delay, so that when the IGBT of the upper bridge arm and the lower bridge arm of a half bridge is switched in a switch state, dead time is needed, namely the upper IGBT and the lower IGBT are in a turn-off state at the same time, otherwise, the situation of straight-through short circuit of the upper bridge arm and the lower bridge arm occurs. The dead time is mainly determined by the difference between the turn-off delay time and the turn-on delay time, and the redundant time, so that the driving signal can be a variable frequency square wave signal with a fixed duty ratio.
The switching frequency fs of the half-bridge switching network is in the frequency range of the resonant frequency fr of the LCC resonant network, the direct current gain of a power supply is reduced along with the increase of the switching frequency of the half-bridge switching network, and meanwhile, in the frequency range, a primary side IGBT device can realize zero voltage turn-on (ZVS) and a secondary side diode can realize zero current turn-off (ZCS).
Due to the fluctuation of the commercial power, in order to make the output voltage of the power supply constant and correspond to different input voltages, the utility model can control the system to provide different switching frequencies fs for the main circuit by combining the change of the direct current gain, and the actual input power is greater than a given value, the switching frequency fs needs to be increased; when the actual input power is smaller than the given value, the switching frequency fs needs to be reduced, and the input power of the power supply is stabilized at the given value through the adjustment of the switching frequency, so that the output power is correspondingly stabilized at the given value.
Meanwhile, the size of the switching frequency fs can be adjusted to control the size of the direct current gain, so that the size of the output voltage is controlled, and finally the power of the magnetron is controlled.
A capacitor C3 is connected in parallel between the drain D and the source S of the IGBT module Q1, and a capacitor C2 is connected in series between the drain D of the IGBT module Q1 and the input end of the primary coil of the transformer. A capacitor C7 is connected in series between the source S of the IGBT module Q2 and the input end of the primary coil of the transformer.
The utility model also utilizes the magnetic integration technology, the leakage inductance of the transformer is used as the resonance inductance of the LCC resonance network, and the leakage inductance of the transformer, the capacitor C2 and the capacitor C3 form the LCC resonance network together.
The power supply controller is provided with a driving control circuit, and the driving control circuit is connected with the grid G of the IGBT module and used for controlling the on-off state of the IGBT module Q1 and the IGBT module Q2.
In order to understand the working state and collect information such as current intensity, the input end of the power supply controller is preferably connected with the output end of the full-bridge rectifier filter, the output end of the IGBT module and the output end of the transformer for collecting current signals.
The transformer transforms the input alternating current and comprises two secondary coils, namely a low-voltage secondary coil and a high-voltage secondary coil. The output end of the low-voltage secondary coil of the transformer is connected with the low-voltage rectification filtering module; the output end of the high-voltage secondary coil of the transformer is connected with the high-voltage rectification filter module.
In an advantageous embodiment of the utility model, the transformer has a tap, to which the low-voltage secondary winding is connected. The low-voltage rectifying and filtering module comprises a rectifying circuit D2, a rectifying circuit D4 and a second LC filtering circuit; the input ends of the rectifying circuit D2 and the rectifying circuit D4 are respectively connected to different taps of a low-voltage secondary coil of the transformer; the second LC filter circuit comprises an inductor L2 and a capacitor C4, the output ends of the rectifying circuit D2 and the rectifying circuit D4 are connected with an inductor L2 of the second LC filter circuit, and an inductor C4 is connected between the high-voltage output end and the low-voltage output end.
In the optimized embodiment of the utility model, the high-voltage rectifying and filtering module comprises a rectifying circuit D9, a rectifying circuit D8, a rectifying circuit D6 and a rectifying circuit D11. A capacitor C9 and a capacitor C8 are arranged between the output end of the rectifying circuit D9 and the rectifying circuit D8 and between the output end of the rectifying circuit D6 and the rectifying circuit D11, and a resistor R3 is connected in parallel to the capacitor C9 and the capacitor C8.
The rectifying circuit D6, the rectifying circuit D8, the rectifying circuit D9 and the rectifying circuit D11 form a high-voltage rectifying network. The four rectifying circuits are in parallel connection because the current required by the magnetron is large, the current is shunted to protect the rectifying diodes, and the capacitor C8 and the capacitor C9 are used as filter capacitors.
The transformer of the utility model is provided with a low-voltage output end and a high-voltage output end, and the voltage output by the low-voltage secondary coil passes through the full-wave rectification function of the rectification circuit D2 and the rectification circuit D4 and then passes through a second LC filter circuit formed by an inductor L2 and a capacitor C4 to provide low-voltage direct-current filament voltage for the magnetron.
While the present invention has been described in detail with reference to the illustrated embodiments, it should not be construed as limited to the scope of the present patent. Various modifications and changes may be made by those skilled in the art without inventive step within the scope of the appended claims.
Claims (8)
1. A microwave soft switch variable frequency power supply is characterized by comprising:
a full bridge rectifier filter; the system is used for being connected with the three-phase alternating current of the commercial power, rectifying and filtering the input commercial power and outputting direct current;
a half-bridge switching network; the input end of the half-bridge switch network is connected with the output end of the full-bridge rectifier filter, and the input direct current is processed and controlled; the half-bridge switch network comprises two IGBT modules, namely an IGBT module Q1 and an IGBT module Q2;
a capacitor C3 is connected in parallel between the drain D and the source S of the IGBT module Q1, and a capacitor C2 is connected in series between the drain D of the IGBT module Q1 and the input end of the primary coil of the transformer;
a capacitor C7 is connected in series between the source S of the IGBT module Q2 and the input end of the primary coil of the transformer;
a power supply controller; the power controller is provided with a drive control circuit, and the drive control circuit is connected with a grid G of the IGBT module and is used for controlling the on-off states of the IGBT module Q1 and the IGBT module Q2;
a transformer; the transformer is used for carrying out transformation processing on input alternating current and comprises two secondary coils, namely a low-voltage secondary coil and a high-voltage secondary coil;
the output end of the low-voltage secondary coil of the transformer is connected with the low-voltage rectification filtering module;
and the output end of the high-voltage secondary coil of the transformer is connected with the high-voltage rectification filtering module.
2. A microwave soft switching variable frequency power supply in accordance with claim 1, wherein: the full-bridge rectifier filter comprises a rectifier circuit D10 and a first LC filter circuit, wherein the first LC filter circuit comprises an inductor L1 and a capacitor C6; both ends of the capacitor C6 are connected to the drain D of the IGBT module Q1 and the source S of the IGBT module Q2, respectively.
3. A microwave soft switching variable frequency power supply in accordance with claim 1, wherein: the input end of the power supply controller is connected with the output end of the full-bridge rectifier filter, the output end of the IGBT module and the output end of the transformer and used for collecting current signals.
4. A microwave soft switching variable frequency power supply in accordance with claim 1, wherein: the transformer has a tap, and the low-voltage secondary coil is connected to the tap.
5. A microwave soft switching variable frequency power supply in accordance with claim 1, wherein: the low-voltage rectifying and filtering module comprises a rectifying circuit D2, a rectifying circuit D4 and a second LC filtering circuit; the input ends of the rectifying circuit D2 and the rectifying circuit D4 are respectively connected to different taps of a low-voltage secondary coil of the transformer;
the second LC filter circuit comprises an inductor L2 and a capacitor C4, the output ends of the rectifying circuit D2 and the rectifying circuit D4 are connected with an inductor L2 of the second LC filter circuit, and an inductor C4 is connected between the high-voltage output end and the low-voltage output end.
6. A microwave soft switching variable frequency power supply in accordance with claim 1, wherein: the high-voltage rectifying and filtering module comprises a rectifying circuit D9, a rectifying circuit D8, a rectifying circuit D6 and a rectifying circuit D11.
7. A microwave soft-switching variable frequency power supply according to claim 6, characterized in that: a capacitor C9 and a capacitor C8 are arranged between the output end of the rectifying circuit D9 and the rectifying circuit D8 and between the output end of the rectifying circuit D6 and the rectifying circuit D11, and a resistor R3 is connected in parallel to the capacitor C9 and the capacitor C8.
8. A microwave soft switching variable frequency power supply in accordance with claim 1, wherein: the drive control circuit is a PWM drive control circuit.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202121782069.6U CN215378781U (en) | 2021-08-02 | 2021-08-02 | Microwave soft switch variable frequency power supply |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202121782069.6U CN215378781U (en) | 2021-08-02 | 2021-08-02 | Microwave soft switch variable frequency power supply |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN215378781U true CN215378781U (en) | 2021-12-31 |
Family
ID=79614209
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202121782069.6U Active CN215378781U (en) | 2021-08-02 | 2021-08-02 | Microwave soft switch variable frequency power supply |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN215378781U (en) |
-
2021
- 2021-08-02 CN CN202121782069.6U patent/CN215378781U/en active Active
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN104065283B (en) | No bridge type PFC AC DC supply convertors | |
| CN111835204B (en) | Zero-reflux power soft switch modulation method and converter of resonant double-active bridge | |
| CN215378781U (en) | Microwave soft switch variable frequency power supply | |
| CN203482094U (en) | Efficient power conversion device | |
| Ogiwara et al. | PWM-controlled soft-switching SEPP high-frequency inverter for induction-heating applications | |
| CN107070218B (en) | High-power soft switch chopper circuit | |
| CN101958649A (en) | Resonant-type stabilized current supply device | |
| CN206250997U (en) | A kind of LCC resonant modes microwave applications device powersupply system | |
| Hasanien et al. | Current source ZCS PFM DC-DC converter for magnetron power supply | |
| Khan et al. | Automatic Resonance Tuning With ON/OFF Soft Switching for Push–Pull Parallel-Resonant Inverter in Wireless Power Transfer | |
| CN210225272U (en) | Direct current power supply for filament of vacuum electronic device | |
| CN113206598A (en) | Series resonant constant-current charging power supply | |
| Wang et al. | Optimal LC filter design method for fully-digital-controlled CRM single-phase inverter | |
| Ogiwara et al. | High frequency induction heating load resonant inverter with voltage-clamped quasi-resonant switched using newly-improved static induction transistors/thyristors and their phase shifted controlled scheme | |
| Dong-Seok | A new control scheme for a Class-D inverter with induction heating jar application by constant switching frequency | |
| Polsripim et al. | A soft switching class D current source inverter for induction heating with ferromagnetic load | |
| CN220273526U (en) | Induction heating power supply circuit with high-frequency isolation on direct current side | |
| Dhiman et al. | Optimal design of battery charging converters based on energy efficiency | |
| CN212909379U (en) | Solid-state high-frequency power supply applied to electron accelerator | |
| CN112436729B (en) | Induction heating device based on power regulation of resonant DC-DC converter | |
| CN103840686A (en) | High-efficiency power supply converter with integrated functions of PFC and DC conversion | |
| CN218449869U (en) | LLC resonant converter regulation and control device | |
| CN113315396B (en) | High-frequency high-voltage pulse charge-discharge power supply system and control method thereof | |
| Kawshty et al. | Design and Analysis of High Frequency Inverter for Induction Heating Application | |
| KR100186471B1 (en) | Inverter loss decrease apparatus for induction heating cooker |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| GR01 | Patent grant | ||
| GR01 | Patent grant |