CN211296683U

CN211296683U - High-power LC oscillating circuit

Info

Publication number: CN211296683U
Application number: CN202020101581.9U
Authority: CN
Inventors: 张雁
Original assignee: Individual
Current assignee: Individual
Priority date: 2020-01-16
Filing date: 2020-01-16
Publication date: 2020-08-18
Anticipated expiration: 2030-01-16

Abstract

The utility model provides a high-power LC oscillating circuit relates to high frequency oscillation circuit technical field, including DC voltage source, resonance inductance and a plurality of levels and the parallelly connected IGBT unit of electric capacity, first order is connected with the parallelly connected IGBT unit of electric capacity with DC voltage source, and the parallelly connected IGBT unit of a plurality of levels and electric capacity is established ties with resonance inductance, and resonance inductance locates between the parallelly connected IGBT unit of two-stage and electric capacity, or locates between DC voltage source and the parallelly connected IGBT unit of first order and electric capacity, or locates between last stage and the parallelly connected IGBT unit of electric capacity and earthing terminal. The utility model provides a topological structure which can drive LC structure to resonate, can generate resonant voltage far higher than power supply voltage and can output higher power; the IGBT power supply has the advantages of simple topological structure, capability of producing a high-power supply with the power level of dozens of kilowatts, low cost and simple control, and any part of IGBT units are short-circuited without influencing the resonance process, and the open circuit can only stop working without other consequences, so the IGBT power supply is more reliable.

Description

High-power LC oscillating circuit

Technical Field

The utility model belongs to the technical field of the high frequency oscillation circuit technique and specifically relates to a high-power LC oscillating circuit.

Background

In the process of converting electric energy, such as a transformer, electric energy is converted into magnetic field energy in a primary coil, the magnetic field energy is captured by a secondary coil with different winding turns, and the magnetic field energy is converted into electric field energy with different voltages or currents.

This kind of energy conversion mode is important electric power application's basic theory, also is the most commonly used technique, and it is widely used, along with switching power supply's utility model, people realize, if can reduce cost and weight by a wide margin with the magnetic field of high frequency, can let the transformer small, and weight is lighter, and the volume and the weight of general high frequency transformer can accomplish only that traditional power frequency transformer is about one tenth, and cost greatly reduced also.

The low-frequency magnetic field energy is converted into high-frequency magnetic field energy, a conversion circuit is needed, the available topological structures in a low-power supply comprise a forward topological structure, a flyback topological structure, a push-pull topological structure, a half-bridge topological structure, a full-bridge topological structure and the like, each topological structure has respective advantages and disadvantages, in the high-power energy conversion occasion, such as high-power energy conversion exceeding thousands of watts or even tens of kilowatts, under the high-frequency condition, the high-power energy conversion can be realized only by adopting an LC resonance structure, and the amplification effect of the LC which can generate a plurality of times of power supply voltage during resonance is utilized to realize higher required output power, at the moment, the topological structures only can be realized by the half-bridge topology and the full-bridge topology, but the half-bridge topology and the full-bridge topology have an important disadvantage that the working frequency is strictly forbidden to, otherwise, the phase advance of the current can be generated, the circuit structure of the full bridge or the half bridge is damaged, and particularly in the case of high-power output, the situation is difficult to avoid, which is also the root cause of the difficulty in the research and development of the high-power circuit of dozens of kilowatts at present.

SUMMERY OF THE UTILITY MODEL

The utility model provides a high-power LC oscillating circuit can produce the resonant voltage who is far higher than mains voltage, can export the topological structure of higher power.

The utility model discloses specifically adopt following technical scheme to realize:

a high-power LC oscillating circuit comprises a direct-current voltage source, a resonant inductor and a plurality of IGBT units connected with a capacitor in parallel, wherein the IGBT unit connected with the capacitor in parallel in the first stage is connected with the direct-current voltage source, the IGBT units connected with the capacitor in parallel in the plurality of stages are connected with the resonant inductor in series, and the resonant inductor is arranged between the two stages of the IGBT units connected with the capacitor in parallel, or between the direct-current voltage source and the IGBT unit connected with the capacitor in parallel in the first stage, or between the IGBT unit connected with the capacitor in parallel in the last stage and a grounding terminal.

Preferably, the plurality of stages of IGBT units connected in parallel with the capacitor include IGBT tubes connected in parallel with the capacitor, wherein a gate of the IGBT tube is connected to the driving circuit, and a collector and an emitter of the IGBT tube are connected to two ends of the capacitor.

Preferably, the inductor of the resonant circuit and the capacitors of the plurality of stages of the IGBT unit form resonance.

Preferably, the drive circuits of the plurality of stages of IGBT units connected in parallel with the capacitor are all driven by the same phase, so that each IGBT tube is synchronously turned on or off.

Preferably, the IGBT tube is an IGBT field effect tube with a damping diode.

The utility model provides a pair of high-power LC oscillating circuit, its beneficial effect lies in: the topological structure can drive an LC structure to resonate, can generate resonant voltage far higher than power supply voltage and can output higher power; the problem that a circuit structure is damaged when a current phase is advanced possibly caused by a full-bridge topology or a half-bridge topology circuit at high power does not exist, the topology structure is simpler, a high-power supply with the power level of dozens of kilowatts can be easily manufactured by adopting the topology structure, the cost is lower, and the control is simpler; when part of the IGBT units are short-circuited, the resonance work is not influenced; when some IGBT units are opened, the operation can be stopped, and other effects are avoided.

Drawings

Fig. 1 is a schematic circuit diagram of embodiment 1 of the high-power LC oscillating circuit of the present invention;

fig. 2 is a waveform diagram of the working point 1 in the embodiment 1 of the high-power LC oscillating circuit of the present invention;

fig. 3 is a waveform diagram of the working point 2 in the embodiment 1 of the high-power LC oscillating circuit of the present invention;

fig. 4 is a waveform diagram of the relative operation between the operating point 1 and the operating point 2 in the embodiment 1 of the high-power LC oscillating circuit of the present invention;

fig. 5 is a schematic circuit diagram of embodiment 2 of the high-power LC oscillating circuit of the present invention;

fig. 6 is a schematic circuit diagram of embodiment 3 of the high-power LC oscillating circuit of the present invention;

fig. 7 is a schematic circuit diagram of embodiment 4 of the high-power LC oscillating circuit of the present invention.

Detailed Description

To further illustrate the embodiments, the present invention provides the accompanying drawings. The accompanying drawings, which are incorporated in and constitute a part of this disclosure, illustrate embodiments of the invention and, together with the description, serve to explain the principles of the embodiments. With these references, one of ordinary skill in the art will appreciate other possible embodiments and advantages of the present invention. Elements in the figures are not drawn to scale and like reference numerals are generally used to indicate like elements.

The present invention will now be further described with reference to the accompanying drawings and detailed description.

Example 1

As shown in fig. 1, the present embodiment provides a high power LC oscillating circuit, which includes a dc voltage source, a resonant circuit formed by an inductor and a capacitor, and two stages of IGBT units, wherein,

the IGBT unit of the first stage comprises a first field effect transistor Q1, the grid electrode of a first IGBT transistor Q1 is connected with a first driving circuit, the collector electrode of a first IGBT transistor Q1 is connected with a direct-current voltage source VCC, the collector electrode of the first IGBT transistor Q1 is connected with one end of a first capacitor C1, the other end of the first capacitor C1 is connected with the emitter electrode of a first IGBT transistor Q1, the emitter electrode of the first IGBT transistor Q1 is further connected with an inductor L of a resonance circuit, and the inductor L can be connected with a capacitor C in parallel to form a parallel resonance relation;

the second stage of IGBT unit includes a second IGBT Q2, the gate of the second IGBT Q2 is connected to the second drive circuit, the collector of the second IGBT Q2 is connected to one end of the inductor L, the collector of the second IGBT Q2 is connected to one end of a second capacitor C2, the other end of the second capacitor C2 is connected to the emitter of the second IGBT Q2, and the emitter of the second IGBT Q2 is grounded.

The inductor L, the first capacitor C1 and the second capacitor C2 form series resonance, and the inductor L can be connected with the capacitors in parallel or not, so that the resonance process is not influenced.

When the driving circuit is used, the first driving circuit and the second driving circuit input driving in the same phase to ensure that the first IGBT tube Q1 and the second IGBT tube Q2 are synchronously turned on or off, and in the embodiment, the first IGBT tube Q1 and the second IGBT tube Q2 are preferably IGBT tubes with damping diodes.

When the IGBT power supply works, each IGBT is synchronously started and conducted, and the conducting time determines the magnitude of resonance energy and the magnitude of resonance voltage. After the IGBT is turned off, the resonance voltage is generated, when the resonance voltage falls back to 0, the IGBT starts to be conducted again, and the process is repeated in a cycle to finish the resonance process. 2-4, from FIG. 2, it can be seen that the peak resonant voltage at operating point 1 is about 2 times the supply voltage; from fig. 3, it can be seen that the resonant voltage peak at operating point 2 is also about 2 times the supply voltage, except that the resonant waveform is negative; from fig. 4, it can be seen that the relative voltage waveform between operating point 1 and operating point 2 is also about 4 times the supply voltage at the peak of the resonant voltage across the LC loop inductance.

Example 2

As shown in fig. 5, the IGBT unit includes three stages, the gate of the third IGBT tube Q3 of the IGBT unit of the third stage is connected to the third drive circuit, the collector of the third IGBT tube Q3 is connected to the emitter of the second IGBT tube Q2, the collector of the third IGBT tube Q3 is connected to one end of the third capacitor C3, the other end of the third capacitor C3 is connected to the emitter of the third IGBT tube Q3, and the emitter of the third IGBT tube Q3 is grounded, unlike embodiment 1.

Example 3

As shown in fig. 6, unlike embodiment 2, although three stages of IGBT cells are included, only the IGBT cell of the first stage and the IGBT cell of the second stage are connected in series, and a resonant inductance is provided between the IGBT cell of the second stage and the IGBT cell of the third stage.

Example 4

As shown in fig. 7, the present embodiment is different from embodiment 2 in that four-stage IGBT cells are included, the gate of the fourth IGBT tube Q4 of each fourth-stage IGBT cell is connected to the fourth driver circuit, the collector of the fourth IGBT tube Q4 is connected to the emitter of the third IGBT tube Q3, the collector of the fourth IGBT tube Q4 is connected to one end of a fourth capacitor C4, the other end of the fourth capacitor C4 is connected to the emitter of the fourth IGBT tube Q4, and the emitter of the fourth IGBT tube Q4 is grounded.

It should be noted that the above embodiments 1-4 are one of the structures of the present circuit, and if the present circuit is changed, for example, only the serial order is simply changed, for example, the inductor L and the capacitor C are not located between the operating point 1 and the operating point 2, but are located between the power source and the power tube, or between the power tube Q2 and the ground, which does not affect the structure and the principle of the present invention.

Additionally, the utility model discloses can increase or reduce power tube and relevant parallel capacitance wantonly, can not influence the working process. Meanwhile, each IGBT is distributed in series on the circuit structure and is connected in parallel with the IGBT, and the capacitor has a voltage division effect on the resonant voltage, so that the more IGBT units are adopted in series, the lower the resonant voltage born by each IGBT is, and the more reliable the operation is. However, it should also be noted that the more IGBT cells that are added, the turn-on power consumption inserted when each IGBT turns on increases accordingly.

The circuit structure shown in the four embodiments is reasonable, the working property of the circuit is not affected, and the reliability of the resonant circuit is higher with more IGBT units, and the following is a part of possible circuit modes, which are used to indicate that the increase or decrease of any part of IGBT units does not affect the resonant process of the circuit and is only related to the reliability of the circuit.

While the invention has been particularly shown and described with reference to a preferred embodiment, it will be understood by those skilled in the art that various changes in form and detail may be made therein without departing from the spirit and scope of the invention as defined by the appended claims.

Claims

1. The high-power LC oscillating circuit is characterized by comprising a direct-current voltage source, a resonant inductor and a plurality of stages of IGBT units connected with a capacitor in parallel, wherein the first stage of IGBT unit connected with the capacitor in parallel is connected with the direct-current voltage source, the plurality of stages of IGBT units connected with the capacitor in parallel are connected with the resonant inductor in series, and the resonant inductor is arranged between the two stages of IGBT units connected with the capacitor in parallel, or between the direct-current voltage source and the first stage of IGBT unit connected with the capacitor in parallel, or between the last stage of IGBT unit connected with the capacitor in parallel and a grounding terminal.

2. The high-power LC oscillating circuit according to claim 1, wherein several stages of said IGBT units connected in parallel with the capacitor comprise IGBT tubes connected in parallel with the capacitor, wherein the gate of said IGBT tube is connected with the driving circuit, and the collector and emitter of said IGBT tube are connected at two ends of said capacitor.

3. A high power LC tank circuit according to claim 2, wherein said resonant inductor is resonant with the capacitance of several stages of said IGBT cells.

4. The high-power LC oscillating circuit according to claim 2, wherein the driving circuits of several stages of said IGBT units connected in parallel with the capacitor all input the same phase driving, so that each said IGBT tube is turned on or off synchronously.

5. A high power LC oscillating circuit according to any one of claims 2-4, characterized in that the IGBT is an IGBT FET with a damping diode.