Digital intermediate frequency power supply

Abstract

The present invention relates to the technical field of power supplies, and specifically discloses a digital intermediate frequency power supply, including: a microprocessor; an IGBT module; and a stepped rectifier circuit matrix. Among them, the stepped rectifier circuit matrix includes at least two series-connected rectifier circuits, and the rectifier circuit is configured by the microprocessor to: by limiting the phase-shift range of the trigger angle of the thyristors constituting the rectifier circuit, and making the phase-shift range of the trigger angle of the thyristors in at least two series-connected rectifier circuits decrease in sequence with the overall rectifier circuit as a reference. The present invention adopts a stepped rectifier circuit matrix, which includes at least a first rectifier circuit and a second rectifier circuit. By configuring and limiting the first phase-shift range of the trigger angle within a set range for the first rectifier circuit, the three-phase industrial frequency alternating current is subjected to a wide-range primary rectification through the first rectifier circuit, and then the second rectifier circuit is used for precise rectification according to the rectification situation of the first rectifier circuit.

Description

Technical Field

[0001] The present invention relates to the technical field of power supplies, and more particularly to a digital intermediate frequency power supply. Background Art

[0002] Generally, a power supply uses a rectifier circuit and an inverter circuit to adjust the output frequency. A common rectifier circuit is a three-phase full-controlled bridge rectifier circuit composed of 6 thyristors. Its defect is that it cannot solve the problem of pulse loss. Therefore, some improved rectifier circuits have emerged on the market. By adding a freewheeling diode to the rectifier circuit, a controllable rectifier circuit with a freewheeling diode is formed. However, the controllable rectifier circuit with a freewheeling diode has a large output ripple and is prone to causing DC core magnetization of the transformer in the transformer circuit. Summary of the Invention

[0003] In view of this, the purpose of the present invention is to provide a digital intermediate frequency power supply.

[0004] To achieve the above purpose, the present invention provides a digital intermediate frequency power supply, including:

[0005] A microprocessor;

[0006] An IGBT module;

[0007] And a stepped rectifier circuit matrix, wherein the stepped rectifier circuit matrix includes at least two series-connected rectifier circuits, and the rectifier circuit is configured by the microprocessor to: by limiting the phase-shifting range of the trigger angle of the thyristors constituting the rectifier circuit, and making the phase-shifting range of the trigger angle of the thyristors in at least two series-connected rectifier circuits decrease in sequence with the overall rectifier circuit as a reference, so that when three-phase industrial frequency alternating current is transmitted to the stepped rectifier circuit matrix through a contactor, the stepped rectifier circuit matrix performs multiple stepped rectifications to obtain pulsating direct current with a set target, and then outputs it to the load at a set frequency through the IGBT module.

[0008] Further, the stepped rectifier circuit matrix includes two series-connected first rectifier circuits and second rectifier circuits, wherein:

[0009] The first rectifier circuit is configured by the microprocessor to: by limiting the first phase-shifting range of the trigger angle of the thyristors constituting the first rectifier circuit;

[0010] The second rectifier circuit is configured by the microprocessor to: by limiting the second phase-shifting range of the trigger angle of the thyristors constituting the second rectifier circuit;

[0011] And the first phase-shifting range is greater than the second phase-shifting range.

[0012] Further, the stepped rectifier circuit matrix includes two series-connected first rectifier circuits and second rectifier circuits,

[0013] And the second rectifier circuit is configured by the microprocessor to: continuously sample the first phase-shifting range of the firing angle of the thyristors in the first rectifier circuit, and dynamically limit the second phase-shifting range of the firing angle of the thyristors constituting the second rectifier circuit according to the sampling results;

[0014] And the second phase-shifting range is smaller than the first phase-shifting range.

[0015] Furthermore, the microprocessor has:

[0016] A processor;

[0017] A configuration unit;

[0018] And an analysis unit;

[0019] The analysis unit is connected to the first sampling unit. The first sampling unit is used to obtain the sampling values of the corresponding firing angles of multiple thyristors in the first rectifier circuit according to a period, and input the collected sampling values of the multiple firing angles to the analysis unit. The analysis unit detects whether each sampling value of the firing angle is a set reference value according to a set detection program. When any one exceeds the set reference value, the analysis unit loads a corresponding preset emergency plan in the analysis unit according to the sampling value, and the configuration unit configures and limits the second phase-shifting range of the firing angle of the thyristors constituting the second rectifier circuit according to the preset emergency plan.

[0020] Furthermore, the processor is connected to the sampling unit, the analysis unit and the configuration unit, and the processor includes a first storage unit and a second storage unit. The first storage unit is used to store the preset emergency plan, and the second storage unit is used to store the detection program.

[0021] Furthermore, the detection program uses the processor as an operating carrier, and the detection program has multiple detection points. Each detection point has a corresponding set reference value, and the multiple detection points correspond to multiple thyristors in the first rectifier circuit respectively.

[0022] Furthermore, the first sampling unit is connected to the first rectifier circuit and is used to obtain the average voltage output by the thyristors.

[0023] Furthermore, the first rectifier circuit is a three-phase bridge fully controlled rectifier circuit composed of 6 thyristors.

[0024] Furthermore, the second rectifier circuit is a three-phase bridge fully controlled rectifier circuit composed of 6 thyristors.

[0025] Furthermore, the IGBT module includes a voltage stabilizing unit and a three-phase inverter.

[0026] The present invention employs a stepped rectifier circuit matrix, which at least includes a first rectifier circuit and a second rectifier circuit. By configuring and defining a first phase-shifting range of the trigger angle within a set range for the first rectifier circuit, three-phase industrial frequency alternating current is subjected to a broad-range primary rectification by the first rectifier circuit, and then precise rectification is performed using the second rectifier circuit according to the rectification situation of the first rectifier circuit. Among them, the first phase-shifting range of the trigger angle of the thyristors constituting the first rectifier circuit is defined and kept unchanged, and then the second phase-shifting range of the trigger angle of the thyristors of the second rectifier circuit is dynamically changed. Thus, when the three-phase industrial frequency alternating current is delivered to the stepped rectifier circuit matrix through a contactor, multiple stepped rectifications are performed by the stepped rectifier circuit matrix to obtain pulsating direct current with a set target. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 is a schematic diagram of the framework principle of the present invention;

[0028] Figure 2 is a schematic diagram of the first rectifier circuit or the second rectifier circuit in the present invention;

[0029] Figure 3 is a schematic diagram of the principle of the IGBT module in the present invention. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0030] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

[0031] Referring to Figures 1 to 3 , to achieve the above object, the present invention aims to provide a digital intermediate frequency power supply, including:

[0032] A microprocessor;

[0033] An IGBT module;

[0034] and a stepped rectifier circuit matrix, wherein the stepped rectifier circuit matrix includes at least two series-connected rectifier circuits, and the rectifier circuit is configured by the microprocessor to: by defining a phase-shifting range of the trigger angle of the thyristors constituting the rectifier circuit, and making the phase-shifting ranges of the trigger angles of the thyristors in at least two series-connected rectifier circuits decrease in sequence with respect to the overall rectifier circuit, so that when three-phase power-frequency alternating current is delivered to the stepped rectifier circuit matrix through the contactor, the stepped rectifier circuit matrix performs multiple stepped rectifications to obtain pulsating direct current with a set target, and then outputs it to the load at a set frequency through the IGBT module.

[0035] In the above, the stepped rectifier circuit matrix includes two series-connected first rectifier circuits and a second rectifier circuit, wherein:

[0036] The first rectifier circuit is configured by the microprocessor to: by defining a first phase-shifting range of the trigger angle of the thyristors constituting the first rectifier circuit;

[0037] The second rectifier circuit is configured by the microprocessor to: by defining a second phase-shifting range of the trigger angle of the thyristors constituting the second rectifier circuit;

[0038] And the first phase-shifting range is greater than the second phase-shifting range.

[0039] In the above, the first rectifier circuit is a three-phase bridge fully controlled rectifier circuit composed of 6 thyristors. The second rectifier circuit is a three-phase bridge fully controlled rectifier circuit composed of 6 thyristors.

[0040] Refer to Figure 2 , Figure 2 shows a circuit diagram of a three-phase bridge fully controlled rectifier circuit. Among them, its composition is: 3 thyristors (VT1, VT3, VT5) with cathodes connected together are called the common cathode group; 3 thyristors (VT4, VT6, VT2) with anodes connected together are called the common anode group. The 3 thyristors connected to the a, b, c three-phase power supplies in the common cathode group are VT1, VT3, VT5 respectively, and the 3 thyristors connected to the a, b, c three-phase power supplies in the common anode group are VT4, VT6, VT2 respectively. The conduction sequence of the thyristors is VT1-VT2-VT3-VT4-VT5-VT6. The rectified output voltage ud of the three-phase bridge fully controlled rectifier circuit pulsates 6 times in one cycle, and the waveform of each pulsation is the same.

[0041] In the above, the stepped rectifier circuit matrix includes two series-connected first rectifier circuits and a second rectifier circuit, and the second rectifier circuit is configured by the microprocessor to: continuously sample the first phase-shifting range of the trigger angles of the thyristors in the first rectifier circuit, and dynamically limit the second phase-shifting range of the trigger angles of the thyristors constituting the second rectifier circuit according to the sampling results; and the second phase-shifting range is smaller than the first phase-shifting range. The present invention adopts a stepped rectifier circuit matrix, which at least includes a first rectifier circuit and a second rectifier circuit. By configuring and limiting the first phase-shifting range of the trigger angles within a set range for the first rectifier circuit, the three-phase industrial frequency alternating current is subjected to a wide-range primary rectification by the first rectifier circuit, and then the second rectifier circuit is used for precise rectification according to the rectification situation of the first rectifier circuit. Among them, the first phase-shifting range of the trigger angles of the thyristors constituting the first rectifier circuit is limited and the first phase-shifting range remains unchanged, and then the second phase-shifting range of the trigger angles of the thyristors of the second rectifier circuit is dynamically changed. Thus, when the three-phase industrial frequency alternating current is transmitted to the stepped rectifier circuit matrix through the contactor, the stepped rectifier circuit matrix performs multiple stepped rectifications to obtain the pulsating direct current with the set target.

[0042] In order to obtain the above configuration, in the present invention, the microprocessor has: a processor; a configuration unit; and an analysis unit; the analysis unit is connected to a first sampling unit, and the first sampling unit is used to obtain the sampling values of the corresponding trigger angles of multiple thyristors in the first rectifier circuit according to a period, and input the collected sampling values of the multiple trigger angles to the analysis unit. The analysis unit detects whether each sampling value of the trigger angle is a set reference value according to the set detection program. When any one exceeds the set reference value, the analysis unit loads the corresponding preset emergency plan in the analysis unit according to the sampling value, and the configuration unit configures and limits the second phase-shifting range of the trigger angles of the thyristors constituting the second rectifier circuit according to the preset emergency plan.

[0043] Further, the processor is connected to the sampling unit, the analysis unit and the configuration unit, and the processor includes a first storage unit and a second storage unit. The first storage unit is used to store the preset emergency plan, and the second storage unit is used to store the detection program.

[0044] Further, the detection program uses the processor as the running carrier, and the detection program has multiple detection points. Each detection point has a corresponding set reference value, and the multiple detection points correspond to multiple thyristors in the first rectifier circuit respectively.

[0045] Further, the first sampling unit is connected to the first rectifier circuit and is used to obtain the average voltage output by the thyristor.

[0046] The IGBT module includes a voltage stabilizing unit and a three-phase inverter. Figure 3 The composition of the IGBT module is given. Among them, in the three-phase inverter of the variable frequency drive, the IGBT is used to control the input frequency of the load end. The isolated output is generated through the coupling winding of the transformer. The voltage stabilizing unit has a primary side voltage stabilizing function and can obtain a good cross-voltage stabilizing effect without opto-coupler feedback or auxiliary winding. It is mainly realized by a wide input constant on-time synchronous buck voltage regulator.

[0047] The three-phase inverter is equivalent to a variable frequency drive, which is a typical application of a three-phase inverter using six isolated gate drivers. Each phase uses high-side and low-side IGBT switches, and the operation of high-power IGBTs needs to be controlled by isolated gate drivers. Each IGBT is driven by a single isolated gate driver, and the driver isolates the high-voltage output from the low-voltage control input. The emitter of the top IGBT floats, so an isolated gate driver must be used. To isolate the high-voltage circuit from the low-voltage control circuit, an isolated gate driver should be used to control the bottom IGBT.

[0048] The present invention adopts a stepped rectifier circuit matrix, which at least includes a first rectifier circuit and a second rectifier circuit. By configuring and defining a first phase-shifting range of the trigger angle of the first rectifier circuit within a set range, the three-phase industrial frequency alternating current is subjected to a wide-range primary rectification through the first rectifier circuit, and then the second rectifier circuit is used for precise rectification according to the rectification situation of the first rectifier circuit. Among them, the first phase-shifting range of the trigger angle of the thyristors constituting the first rectifier circuit is defined and the first phase-shifting range is kept unchanged, and then the second phase-shifting range of the trigger angle of the thyristors of the second rectifier circuit is dynamically changed. Thus, when the three-phase industrial frequency alternating current is delivered to the stepped rectifier circuit matrix through a contactor, the stepped rectifier circuit matrix performs multiple stepped rectifications to obtain the pulsating direct current with the set target.

[0049] Although the embodiments of the present invention have been shown and described, for those of ordinary skill in the art, it can be understood that various changes, modifications, substitutions and variations can be made to these embodiments without departing from the principles and spirits of the present invention. The scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. Digital intermediate frequency power supply, characterized in that: include: microprocessor; IGBT modules; and a step-type rectifier circuit matrix, wherein the step-type rectifier circuit matrix includes at least two rectifier circuits connected in series, and the rectifier circuits are configured by a microprocessor to: by limiting the phase shift range of the trigger angle of the thyristors constituting the rectifier circuit, and making the phase shift range of the trigger angle of the thyristors in at least two rectifier circuits connected in series decrease in sequence with the rectifier circuit as a whole as a reference, so that when the three-phase industrial frequency alternating current is transmitted to the step-type rectifier circuit matrix through the contactor, the step-type rectifier circuit matrix performs multiple step-by-step rectification to obtain the set target pulsating direct current, and then outputs it to the load at the set frequency through the IGBT module; The ladder-type rectifier circuit matrix includes two first rectifier circuits and a second rectifier circuit connected in series, wherein: The first rectifier circuit is configured by the microprocessor to: define a first phase shift range of a trigger angle of a thyristor constituting the first rectifier circuit; The second rectifier circuit is configured by the microprocessor to: define a second phase shift range of the trigger angle of the thyristor constituting the second rectifier circuit; And the first phase shift range is greater than the second phase shift range; The second rectifier circuit is configured by the microprocessor to: continuously sample the first phase shift range of the trigger angle of the thyristor in the first rectifier circuit, and dynamically limit the second phase shift range of the trigger angle of the thyristor constituting the second rectifier circuit according to the sampling result; And the second phase shift range is smaller than the first phase shift range.

2. The digital intermediate frequency power supply according to claim 1, characterized in that: The microprocessor has: processor; Configuration unit; and the unit of analysis; The analysis unit is connected to the first sampling unit, and the first sampling unit is used to obtain sampling values ​​of multiple trigger angles corresponding to multiple thyristors in the first rectifier circuit according to a period, and input the collected sampling values ​​of the multiple trigger angles into the analysis unit. The analysis unit detects whether the sampling value of each trigger angle is a set reference value according to a set detection procedure. When any one exceeds the set reference value, the analysis unit loads the corresponding preset emergency plan in the analysis unit according to the sampling value, and the configuration unit configures a second phase shift range that limits the trigger angle of the thyristor constituting the second rectifier circuit according to the preset emergency plan.

3. The digital intermediate frequency power supply according to claim 2, characterized in that: The processor is connected to the sampling unit, the analysis unit and the configuration unit, and the processor includes a first storage unit and a second storage unit, wherein the first storage unit is used to store a preset emergency plan, and the second storage unit is used to store a detection program.

4. The digital intermediate frequency power supply according to claim 3, characterized in that: The detection program uses the processor as an operating carrier, and the detection program has multiple detection points, each detection point has a corresponding set reference value, and the multiple detection points correspond to multiple thyristors in the first rectifier circuit respectively.

5. The digital intermediate frequency power supply according to claim 2, characterized in that: The first sampling unit is connected to the first rectifier circuit and is used to obtain an average voltage output by the thyristor.

6. The digital intermediate frequency power supply according to claim 1, characterized in that: The first rectifier circuit is a three-phase bridge-type fully-controlled rectifier circuit composed of 6 thyristors.

7. The digital intermediate frequency power supply according to claim 1, characterized in that: The second rectifier circuit is a three-phase bridge-type fully-controlled rectifier circuit composed of 6 thyristors.

8. The digital intermediate frequency power supply according to claim 1, characterized in that: The IGBT module includes a voltage stabilizing unit and a three-phase inverter.

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