Silicon carbide inversion induction heating power supply
By adopting silicon carbide inverter devices and designing silicon carbide inverter bridges, inverter absorption plates and transformer RC absorption components, the problems of low efficiency and high failure rate of existing high-frequency induction heating power inverter devices are solved, and more efficient and reliable high frequency induction heating power supply.
Patent Information
- Application Number
- CN202421160101.0
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-05-24
- Publication Date
- 2025-02-07
- Estimated Expiration
- 2034-05-24
AI Technical Summary
The inverter devices of the existing high-frequency induction heating power supply above 1000KHz have low efficiency and high failure rate. At high frequency, the on-resistance of the MOSFET increases, and the heating power increases, forming a vicious cycle.
Silicon carbide (SiC) inverter devices are used to design silicon carbide inverter bridges and inverter absorption plates, and combined with transformer RC absorption components to improve inverter efficiency and reliability.
It improves the inverting efficiency and reliability of high-frequency induction heating power supply, reduces the oscillation current and heating of the SiC module, and achieves a higher power output.
Smart Images
Figure CN222441566U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to a silicon carbide inverter induction heating power supply, which belongs to the SiC-Mosfet module inverter technology in electrical equipment, specifically a high-power 1000KHz ultra-high frequency induction heating power supply; the product of the utility model is used in high-frequency brazing, high-frequency quenching, semiconductor melting, high-frequency annealing and other induction heating application fields. Background Art
[0002] At present, the existing high-frequency induction heating power supply above 1000KHz generally uses MOSFET tubes or electron tubes as inverter devices. The inverter efficiency of electron tubes is only 40%-50%, the power factor is also lower than 0.60, and the failure rate is particularly high. When using MOSFET inverter, the current of a single MOSFET tube is small, generally within 100A, and multiple MOSFET tubes need to be used in parallel. Due to the uneven current distribution caused by the circuit layout, the different switching speeds between multiple tubes, and the different delays between multiple drive signals, the current between multiple tubes is uneven, which is prone to local overcurrent and overheating. Once one of the MOSFET tubes is damaged, most of the MOSFETs in the entire inverter bridge will burn out, and all can only be replaced, and the reliability is relatively poor. And MOSFET is a silicon-based material. As the PN junction temperature rises, the on-resistance of the MOSFET increases, and the heat generation power also increases, forming a vicious circle. Therefore, the higher the frequency, the lower the current used. When using above 1000kHz, a 100A MOSFET can only be used at 20-30A and must be water-cooled. An inverter bridge consisting of four MOSFETs can only output 10-20KW. Utility Model Content
[0003] The purpose of the utility model is to solve the technical problems existing in the background technology, and for this purpose, a silicon carbide inverter induction heating power supply is provided.
[0004] In order to achieve the above purpose, the technical solution adopted by the utility model is as follows:
[0005] A silicon carbide inverter induction heating power supply, comprising a three-phase input circuit, a voltage chopper circuit, a silicon carbide inverter circuit and an output circuit;
[0006] The positive and negative ends of the rectifier output of the three-phase input circuit are connected to the positive and negative ends of the DC bus respectively;
[0007] The voltage chopper circuit comprises a filter capacitor group 1, a non-inductive capacitor, a chopper IGBT, a shunt, a reverse freewheeling diode, a filter inductor, and a filter capacitor group 2; wherein the filter capacitor group 1 and the non-inductive capacitor are connected in parallel to the positive and negative ends of the DC bus, the positive end of the DC bus is connected in series with the chopper IGBT, the negative end of the DC bus is connected in series with the shunt, a reverse freewheeling diode is connected in parallel between the output end of the chopper IGBT and the negative end of the DC bus, the output end of the chopper IGBT is connected in series with the filter inductor, and the filter capacitor group 2 is connected in parallel between the output end of the filter inductor and the shunt;
[0008] The silicon carbide inverter circuit comprises a silicon carbide inverter bridge, wherein the input end of the silicon carbide inverter bridge is connected to the second phase of the filter capacitor group, and the output end of the silicon carbide inverter bridge is connected to the output circuit.
[0009] The following is a technical solution further defined by the present utility model, wherein the three-phase input circuit includes a three-phase power supply, a circuit breaker, a fuse, a three-phase rectifier bridge and an absorption capacitor; wherein the three-phase electricity of the three-phase power supply is electrically connected to the three-phase input end of the three-phase rectifier bridge through the circuit breaker, and the A phase and C phase of the three-phase power supply are connected in series with the fuse; the positive and negative ends of the rectifier output of the three-phase rectifier bridge are respectively connected to the positive and negative ends of the DC bus, and the absorption capacitor is connected in parallel to the positive and negative ends of the DC bus.
[0010] The following is a technical solution further defined by the present utility model: the silicon carbide inverter bridge includes four silicon carbide field effect transistors SiC 1-SiC 4 and two inverter absorption boards RDC1 and RDC2;
[0011] The inverter absorption board RDC1 is composed of a capacitor C3, a diode D2, a capacitor C4, and a diode D3 connected in series, wherein the capacitor C3 is connected to the positive input terminal of the silicon carbide inverter bridge, and the diode D3 is connected to the negative input terminal of the silicon carbide inverter bridge; the middle connection point of the diode D2 and the capacitor C4 is further connected to the middle connection point of the silicon carbide field effect transistors SiC1 and SiC2 and serves as the positive output terminal of the silicon carbide inverter bridge; one side of the resistor R1 is connected between the diode D2 and the capacitor C3, and the other side is connected to the negative input terminal of the silicon carbide inverter bridge; one side of the resistor R2 is connected between the diode D3 and the capacitor C4, and the other side is connected to the positive input terminal of the silicon carbide inverter bridge;
[0012] The inverter absorption board RDC2 is composed of a capacitor C5, a diode D4, a capacitor C6, and a diode D5 connected in series, wherein the capacitor C5 is connected to the positive input terminal of the silicon carbide inverter bridge, and the diode D5 is connected to the negative input terminal of the silicon carbide inverter bridge; the middle connection point of the diode D4 and the capacitor C6 is further connected to the middle connection point of the silicon carbide field effect transistors SiC3 and SiC4 and serves as the negative output terminal of the silicon carbide inverter bridge; one side of the resistor R3 is connected between the diode D4 and the capacitor C5, and the other side is connected to the negative input terminal of the silicon carbide inverter bridge; one side of the resistor R4 is connected between the diode D5 and the capacitor C6, and the other side is connected to the positive input terminal of the silicon carbide inverter bridge.
[0013] The following is a technical solution further defined by the present utility model, wherein the output circuit includes a DC blocking capacitor group, an isolation transformer, a transformer RC absorption component, a resonant capacitor group and an induction coil;
[0014] The output end of the silicon carbide inverter bridge is connected to the primary side of the isolation transformer through a DC blocking capacitor group, and a transformer RC absorption component is connected in parallel to the primary side of the isolation transformer; the secondary side of the isolation transformer is connected to the induction coil through a resonant capacitor group.
[0015] Compared with the prior art, the utility model has the following technical effects:
[0016] The utility model adopts silicon carbide inverter devices, which have the characteristics of large single-tube current, high switching speed, low on-resistance, low failure rate, small switching loss, high temperature resistance, etc., which greatly improves the inverter efficiency and reliability of the high-frequency induction heating power supply, and can make the power of the high-frequency induction heating power supply larger; the RDC inverter absorption board is redesigned, which is specially designed for the high-frequency inverter of SiC modules. Since the switching speed of the SiC module is relatively fast, high voltage will be generated during switching, which can be timely absorbed by the RDC inverter absorption board; the transformer RC absorption component is redesigned, which is connected in parallel at both ends of the primary winding of the isolation transformer to absorb the high-frequency parasitic oscillation generated by the primary side of the transformer, prevent the inverter bridge output end from generating high-frequency parasitic oscillation current, reduce the oscillation current of the SiC module, and reduce the heating of the SiC module.
[0017] The present invention will be further described below in conjunction with the accompanying drawings and embodiments. BRIEF DESCRIPTION OF THE DRAWINGS
[0018] In order to more clearly illustrate the embodiments of the utility model or the technical solutions in the prior art, the drawings required for use in the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the utility model. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.
[0019] Figure 1It is a schematic diagram of the overall circuit connection relationship of the utility model;
[0020] Figure 2 It is a schematic diagram of the circuit connection relationship of the three-phase input circuit in the utility model;
[0021] Figure 3 It is a schematic diagram of the circuit connection relationship of the voltage chopper circuit in the utility model;
[0022] Figure 4 It is a schematic diagram of the circuit connection relationship of the silicon carbide inverter circuit in the utility model. DETAILED DESCRIPTION
[0023] In order to make the above-mentioned purposes, features and advantages of the utility model more obvious and easy to understand, the specific implementation methods of the utility model are described in detail below in conjunction with the accompanying drawings. In the following description, many specific details are set forth to facilitate a full understanding of the utility model. However, the utility model can be implemented in many other ways different from those described herein, and those skilled in the art can make similar improvements without violating the connotation of the utility model, so the utility model is not limited by the specific embodiments disclosed below.
[0024] like Figure 1-4 As shown, a silicon carbide inverter induction heating power supply is provided, including a three-phase input circuit, a voltage chopper circuit, a silicon carbide inverter circuit and an output circuit.
[0025] like Figure 2 As shown, the three-phase input circuit includes a 380VAC three-phase power supply, a circuit breaker K1, fuses F1, F2, a three-phase rectifier bridge BD1 and an absorption capacitor C1. The input voltage is a three-phase 380VAC 50Hz power frequency power to the circuit breaker K1, where F1 and F2 fuses are installed on phases A and C, and then the three-phase input voltage is rectified into DC through the three-phase rectifier bridge BD1, DC+ and DC- are the DC power input terminals. C1 is the absorption capacitor of the rectifier bridge, and the absorption capacitor C1 is connected in parallel to the positive terminal DC+ and the negative terminal DC- of the DC bus.
[0026] like Figure 3As shown, the voltage chopper circuit includes a filter capacitor group 1 GCA1, a non-inductive capacitor, a chopper IGBT (IGBT5), a shunt FL, a reverse freewheeling diode D1, a filter inductor L1, and a filter capacitor group 2 GCA2. After the positive end DC+ and the negative end DC- of the DC bus pass through the parallel filter capacitor group 1 GCA1, DC+ is then chopped and voltage-regulated output through the series chopper IGBT (IGBT5), DC- is detected by the series shunt FL, and then a reverse freewheeling diode D1 is connected in parallel between the output end of the chopper IGBT (IGBT5) and the DC-end for the subsequent flow after the chopper IGBT is turned off, and the output end of the chopper IGBT (IGBT5) is LC filtered through the series filter inductor L1 and the filter capacitor group 2 GCA2 connected in parallel between the output end of the filter inductor L1 and the shunt FL to reduce the harmonic content, and the chopped DC voltage is then connected to the silicon carbide inverter circuit.
[0027] like Figure 4 As shown, the silicon carbide inverter circuit includes a silicon carbide inverter bridge (referred to as SiC inverter bridge), wherein the SiC inverter bridge includes four silicon carbide field effect transistors SiC 1-SiC 4 and two inverter absorption boards RDC1 and RDC2. The chopped DC voltage passes through the SiC inverter bridge composed of four silicon carbide field effect transistors SiC 1-SiC 4. RDC1 and RDC2 are inverter absorption boards used to absorb the high voltage generated when the silicon carbide field effect transistor (referred to as SiC-Mosfet) is switched to prevent the SiC-Mosfet from overvoltage breakdown.
[0028] The RDC1 inverter absorption board is designed with a capacitor C3-diode D2-capacitor C4-diode D3 series structure, wherein the capacitor C3 is connected to the positive input terminal of the SiC inverter bridge, and the diode D3 is connected to the negative input terminal of the SiC inverter bridge; the middle connection point of the diode D2 and the capacitor C4 is connected to the middle connection point of the silicon carbide field effect transistors SiC1 and SiC2 and serves as the positive output terminal of the SiC inverter bridge; one side of the resistor R1 is connected between the diode D2 and the capacitor C3, and the other side is connected to the negative input terminal of the SiC inverter bridge, and one side of the resistor R2 is connected between the diode D3 and the capacitor C4, and the other side is connected to the positive input terminal of the SiC inverter bridge.
[0029] The RDC2 inverter absorption board is designed with a capacitor C5-diode D4-capacitor C6-diode D5 series structure, wherein the capacitor C5 is connected to the positive input terminal of the SiC inverter bridge, and the diode D5 is connected to the negative input terminal of the SiC inverter bridge; the middle connection point of the diode D4 and the capacitor C6 is connected to the middle connection point of the silicon carbide field effect transistors SiC3 and SiC4 and serves as the negative output terminal of the silicon carbide inverter bridge; one side of the resistor R3 is connected between the diode D4 and the capacitor C5, and the other side is connected to the negative input terminal of the SiC inverter bridge; one side of the resistor R4 is connected between the diode D5 and the capacitor C6, and the other side is connected to the positive input terminal of the SiC inverter bridge.
[0030] like Figure 1 As shown, the output circuit includes a DC blocking capacitor group CAP1, an isolation transformer TR1, a transformer RC absorption component RC1, a resonant capacitor group CAP2 and an induction coil Coil. The SiC inverter bridge outputs a high-frequency AC current connected to the output terminal TM1 through a cable, and then connected to the input terminal TM2 through a cable, flows through the DC blocking capacitor group CAP1, blocks the DC component current, and only allows the high-frequency AC current to flow, and then inputs into the primary side of the isolation transformer TR1. The transformer RC absorption component RC1 is connected in parallel to the primary side of the isolation transformer TR1 to absorb the high-frequency parasitic oscillation current. The secondary side of the isolation transformer TR1 outputs a high-frequency current through the resonant capacitor group CAP2, and then connected to the output terminal TEM3. The high-frequency current is connected to the induction coil Coil through the output terminal TEM3.
[0031] The above is only a preferred embodiment of the utility model, and does not limit the utility model in any form. Any technician familiar with the field can make many possible changes and modifications to the technical solution of the utility model by using the above disclosed methods and technical contents without departing from the scope of the technical solution of the utility model, or modify it into an equivalent embodiment of equivalent changes. Therefore, all equivalent changes made according to the shape, structure and principle of the utility model without departing from the content of the technical solution of the utility model should be included in the protection scope of the utility model.
Claims
1. A silicon carbide inverter induction heating power supply, characterized in that: It includes a three-phase input circuit, a voltage chopper circuit, a silicon carbide inverter circuit and an output circuit; The positive and negative ends of the rectifier output of the three-phase input circuit are connected to the positive and negative ends of the DC bus respectively; The voltage chopper circuit comprises a filter capacitor group 1, a non-inductive capacitor, a chopper IGBT, a shunt, a reverse freewheeling diode, a filter inductor, and a filter capacitor group 2; wherein the filter capacitor group 1 and the non-inductive capacitor are connected in parallel to the positive and negative ends of the DC bus, the positive end of the DC bus is connected in series with the chopper IGBT, the negative end of the DC bus is connected in series with the shunt, a reverse freewheeling diode is connected in parallel between the output end of the chopper IGBT and the negative end of the DC bus, the output end of the chopper IGBT is connected in series with the filter inductor, and the filter capacitor group 2 is connected in parallel between the output end of the filter inductor and the shunt; The silicon carbide inverter circuit comprises a silicon carbide inverter bridge, wherein the input end of the silicon carbide inverter bridge is connected to the second phase of the filter capacitor group, and the output end of the silicon carbide inverter bridge is connected to the output circuit.
2. A silicon carbide inverter induction heating power supply as claimed in claim 1, characterized in that: The three-phase input circuit includes a three-phase power supply, a circuit breaker, a fuse, a three-phase rectifier bridge and an absorption capacitor; wherein the three-phase electricity of the three-phase power supply is electrically connected to the three-phase input terminals of the three-phase rectifier bridge through the circuit breaker, and the A phase and the C phase of the three-phase power supply are connected in series with the fuse; the positive and negative terminals of the rectifier output of the three-phase rectifier bridge are respectively connected to the positive and negative terminals of the DC bus, and the absorption capacitor is connected in parallel to the positive and negative terminals of the DC bus.
3. A silicon carbide inverter induction heating power supply as claimed in claim 1, characterized in that: The silicon carbide inverter bridge includes four silicon carbide field effect transistors SiC 1-SiC 4 and two inverter absorption boards RDC1 and RDC2; The inverter absorption board RDC1 is composed of a capacitor C3, a diode D2, a capacitor C4, and a diode D3 connected in series, wherein the capacitor C3 is connected to the positive input terminal of the silicon carbide inverter bridge, and the diode D3 is connected to the negative input terminal of the silicon carbide inverter bridge; the middle connection point of the diode D2 and the capacitor C4 is further connected to the middle connection point of the silicon carbide field effect transistors SiC1 and SiC2 and serves as the positive output terminal of the silicon carbide inverter bridge; one side of the resistor R1 is connected between the diode D2 and the capacitor C3, and the other side is connected to the negative input terminal of the silicon carbide inverter bridge; one side of the resistor R2 is connected between the diode D3 and the capacitor C4, and the other side is connected to the positive input terminal of the silicon carbide inverter bridge; The inverter absorption board RDC2 is composed of a capacitor C5, a diode D4, a capacitor C6, and a diode D5 connected in series, wherein the capacitor C5 is connected to the positive input terminal of the silicon carbide inverter bridge, and the diode D5 is connected to the negative input terminal of the silicon carbide inverter bridge; the middle connection point of the diode D4 and the capacitor C6 is further connected to the middle connection point of the silicon carbide field effect transistors SiC3 and SiC4 and serves as the negative output terminal of the silicon carbide inverter bridge; one side of the resistor R3 is connected between the diode D4 and the capacitor C5, and the other side is connected to the negative input terminal of the silicon carbide inverter bridge; one side of the resistor R4 is connected between the diode D5 and the capacitor C6, and the other side is connected to the positive input terminal of the silicon carbide inverter bridge.
4. A silicon carbide inverter induction heating power supply as claimed in claim 1, characterized in that: The output circuit includes a DC blocking capacitor group, an isolation transformer, a transformer RC absorption component, a resonant capacitor group and an induction coil; The output end of the silicon carbide inverter bridge is connected to the primary side of the isolation transformer through a DC blocking capacitor group, and a transformer RC absorption component is connected in parallel to the primary side of the isolation transformer; The secondary side of the isolation transformer is connected to the induction coil through a resonant capacitor bank.