Multi-channel modular direct-current power supply structure

Abstract

The utility model discloses a multichannel modular direct current power supply structure, which comprises a plurality of direct current output modules and a direct current bus power supply module capable of synchronously supplying power to the plurality of direct current output modules. The direct current output module comprises a direct current input terminal TM2, inversion IGBT high-frequency absorption capacitors C1 and C2, a full-bridge inversion circuit, a blocking rectification output module and a direct current output terminal TM3; the input end of the direct current input terminal TM2 is electrically connected with the output end of the direct current bus power supply module, the output end of the direct current input terminal TM2 is electrically connected with the inversion IGBT high-frequency absorption capacitors C1 and C2 and the input end of the full-bridge inversion circuit in sequence, and the output end of the full-bridge inversion circuit is electrically connected with the input end of the direct current blocking rectification output module to convert medium-frequency alternating current into direct current to be output. And the output end of the direct current blocking rectification output module is electrically connected with the direct current output terminal TM3. The system can share the DC bus for power supply, and has the advantages of high power factor, high adjustment precision, no influence of power grid fluctuation on output stability, high control precision and high reliability.

Description

Technical Field

[0001] The utility model relates to a multi-channel modular direct current power supply structure, belonging to the technical field of power electronic products. Background Art

[0002] At present, most commonly used DC power supplies adopt two structures. One is to adjust the power frequency input power supply through thyristors, with a control cycle of 50Hz, and then convert and transform the 50Hz input through a power frequency transformer, and then rectify it into DC and output it. The other is to use thyristors to adjust the voltage and rectify it, and then use IGBT modules (Insulated Gate Bipolar Transistor, abbreviated as IGBT, insulated gate bipolar transistor) for medium frequency inversion, and then use medium frequency transformers to convert it and then rectify it for output. The problem with these two structures is that they use independent thyristor voltage regulation circuits and cannot share the DC bus power supply. The thyristor voltage regulation method has a low power factor and generates large harmonics, which has a particularly large impact on the quality of the power grid. At the same time, the control accuracy is also relatively low, and the output is particularly affected by power grid fluctuations. The power frequency transformer is large in size, heavy in weight, and relatively low in efficiency. Most products use analog regulation, and the regulation accuracy is low. Therefore, there is an urgent need for a DC power supply structure that can share the DC bus power supply, has a high power factor, good reliability, fast regulation response speed and high accuracy. Utility Model Content

[0003] The technical problem to be solved by the utility model is that the existing DC power supply structure adopts independent thyristor voltage regulation circuit, which cannot share the DC bus power supply, and the thyristor voltage regulation method has low power factor, large harmonics, and has a particularly large impact on the quality of the power grid. At the same time, the control accuracy is relatively low, and the output is particularly affected by power grid fluctuations. The transformer that adopts the industrial frequency transformer is large in size, heavy in weight, and relatively low in efficiency. Most products adopt analog regulation, which has low regulation accuracy.

[0004] In order to solve the above technical problems, the utility model provides a multi-channel modular DC power supply structure, so that the DC power supply structure can share the DC bus power supply, and at the same time has a high power factor, high regulation accuracy, and is not affected by power grid fluctuations. The output stability, high control accuracy, and high reliability.

[0005] In order to achieve the above technical objectives and the above technical effects, this application is implemented through the following technical solutions:

[0006] A multi-channel modular DC power supply structure comprises a mounting frame, a DC bus power supply module and a DC output module, wherein the DC bus power supply module is detachably arranged in the mounting frame, and a plurality of DC output modules are detachably arranged and separately arranged in the mounting frame, and the DC output modules are all electrically connected to the DC bus power supply module.

[0007] Preferably, the DC bus power supply module includes a three-phase power supply, a circuit breaker K1, a three-phase rectifier bridge BD1, an absorption capacitor C4, an inverter filter capacitor group GCA2 and a DC bus output terminal TM1;

[0008] The output end of the three-phase power supply is electrically connected to the rectifier signal input end of the three-phase rectifier bridge BD1 through the circuit breaker K1, and the output end of the three-phase rectifier bridge BD1 is electrically connected to the absorption capacitor C4, the inverter filter capacitor group GCA2 and the DC bus output terminal TM1 in sequence, and a charging buffer circuit is connected in series between the absorption capacitor C4 and the inverter filter capacitor group GCA2.

[0009] Furthermore, the charging buffer circuit includes a buffer contactor KP2, a buffer resistor R1 and a resettable fuse SF1. The buffer resistor R1 and the resettable fuse SF1 are connected in parallel to the buffer contactor KP2. One end of the buffer contactor KP2 is electrically connected to the absorption capacitor C4, and the other end is electrically connected to the inverter filter capacitor group through the filter inductor IND1.

[0010] Preferably, the DC output module includes a DC input terminal TM2, an inverter IGBT high-frequency absorption capacitor C1, an inverter IGBT high-frequency absorption capacitor C2, a full-bridge inverter circuit, a DC isolation rectifier output module and a DC output terminal TM3;

[0011] The DC input terminal TM2 input end is electrically connected to the DC bus power supply module output end, and the DC input terminal TM2 output end is electrically connected to the inverter IGBT high-frequency absorption capacitor C1, the inverter IGBT high-frequency absorption capacitor C2 and the full-bridge inverter circuit input end in sequence to realize medium-frequency AC conversion output, and the full-bridge inverter circuit output end is electrically connected to the DC isolation rectifier output module input end to convert the medium-frequency AC into DC current output, and the DC isolation rectifier output module output end is electrically connected to the DC output terminal TM3.

[0012] Furthermore, the full-bridge inverter circuit includes four insulated gate bipolar transistors IGBT1-IGBT4, and a first circuit formed by connecting the insulated gate bipolar transistors IGBT1 and IGBT2 in series is connected in parallel with a second circuit formed by connecting the insulated gate bipolar transistors IGBT3 and IGBT4 in series.

[0013] Furthermore, the DC blocking and rectifying output module includes a DC blocking capacitor CAP1, an intermediate frequency isolation transformer TR1, an intermediate frequency rectifier bridge BG2, an output smoothing reactor IND2, a large-capacity output capacitor CAP3 and a current detection shunt FL1;

[0014] The DC blocking capacitor CAP1 is electrically connected between the output end of the full-bridge inverter circuit and the input end of the intermediate frequency isolation transformer TR1 to isolate the DC component; the output end of the intermediate frequency isolation transformer TR1 is electrically connected to the intermediate frequency rectifier bridge BG2 to rectify the intermediate frequency current output by the transformer into a DC current; one of the output ends of the intermediate frequency rectifier bridge BG2 is electrically connected to the output smoothing reactor IND2 and the large-capacity output capacitor CAP3 in sequence; the current detection shunt FL1 is connected in parallel with the output end of the intermediate frequency isolation transformer TR1 to detect the output DC current after rectification by the intermediate frequency rectifier bridge BG2.

[0015] Preferably, the DC bus power supply module and the DC output module both adopt independent drawer-type chassis.

[0016] Preferably, a plurality of air cooling mechanisms corresponding to the DC bus power supply module and the DC output module are provided on the mounting frame.

[0017] The multi-channel modular DC power supply structure provided by the utility model has the following advantages:

[0018] 1. When the utility model is in use, it has a DC output module structure with multiple independent channels. Each module can independently control the output. The DC input ends of the multiple modules are connected to a common DC bus power supply module, which provides main circuit power supply. The DC bus power supply module and the DC output module respectively use independent drawer-type chassis, which is convenient for increasing the number of channels and repairing and replacing.

[0019] 2. When the utility model is used, the industrial frequency input power is directly rectified into DC through a diode full bridge, with a high power factor, and then inverted through the IGBT module medium frequency, and the duty cycle is used to adjust the inverter output pulse width to debug the output voltage, with high adjustment accuracy, and the output stability is not affected by power grid fluctuations. The medium frequency isolation transformer is used for output, and the output and input isolation voltage can reach more than 5000V, ensuring the safety of the output circuit. The control method combined with digital DSP+CPLD is adopted, with high control accuracy and high reliability.

[0020] 3. When the utility model is used, a common DC bus power supply module is used to power multiple DC output modules, which greatly reduces the volume of the DC input module, reduces the number of components and circuit complexity, and reduces the cost of the equipment. The DC bus power supply module adopts diode full-bridge rectification, does not use thyristor voltage regulation, has high power factor and good reliability.

[0021] 4. The multi-channel modular DC power supply structure of the utility model can connect multiple heating resistors at the same time to independently control the heating power and heating temperature of multiple areas; the same heating element resistor can also be divided into multiple areas and connected to multiple DC output modules respectively, so as to realize independent control of the heating power and temperature of different areas of the same heating element resistor; multiple DC output module outputs can also be directly connected in parallel to heat the same heating element resistor, which can be applied to resistance heating furnaces with multi-temperature zone control requirements, including single crystal silicon crystal growth resistance furnaces, low-temperature crystal growth resistance furnaces, multi-temperature zone control heat treatment applications, etc. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 This is the appearance diagram of a DC output module in a multi-channel modular DC power supply structure mainly embodied in the utility model;

[0023] Figure 2 This is an axial schematic diagram of the overall structure of a multi-channel modular DC power supply structure mainly embodied in the utility model;

[0024] Figure 3 This is a circuit diagram of a DC bus power supply module in a multi-channel modular DC power supply structure of the utility model;

[0025] Figure 4 This is a circuit diagram of a DC output module in a multi-channel modular DC power supply structure of the utility model;

[0026] Figure 5 This is a schematic diagram of a multi-module connection circuit of a multi-channel modular DC power supply structure of the utility model;

[0027] In the figure:

[0028] 1-installation frame; 2-DC bus power supply module; 20-charging buffer circuit; 3-DC output module; 30-full-bridge inverter circuit; 31-DC isolation rectifier output module. DETAILED DESCRIPTION

[0029] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present utility model, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technical personnel in the field without creative work are within the scope of protection of the present utility model.

[0030] Reference Figure 1 and Figure 2A multi-channel modular DC power supply structure includes a mounting frame 1, a DC bus power supply module 2 and a DC output module 3. The DC bus power supply module 2 can be detachably mounted in the mounting frame 1. A plurality of DC output modules 3 can be detachably mounted and are separately arranged in the mounting frame 1. The DC output modules 3 are all electrically connected to the DC bus power supply module 2 so as to power multiple DC output modules 3 through a group of DC bus power supply modules 2, thereby greatly reducing the volume of the DC input module, reducing the number of components and the complexity of the circuit, and reducing the cost of the equipment. In this embodiment, the DC bus power supply module 2 and the DC output module 3 both adopt independent drawer-type chassis, and the number of DC output modules 3 is preferably an even number.

[0031] Reference Figure 3 , the DC bus power supply module 2 includes a three-phase power supply, a circuit breaker K1, a three-phase rectifier bridge BD1, an absorption capacitor C4, an inverter filter capacitor group GCA2 and a DC bus output terminal TM1. In this embodiment, the three-phase power supply is preferably a three-phase 380VAC power frequency 50Hz power supply;

[0032] The output end of the three-phase power supply is electrically connected to the rectifier signal input end of the three-phase rectifier bridge BD1 through the circuit breaker K1. The output end of the three-phase rectifier bridge BD1 is electrically connected to the absorption capacitor C4, the inverter filter capacitor group GCA2 and the DC bus output terminal TM1 in sequence. A charging buffer circuit 20 is connected in series between the absorption capacitor C4 and the inverter filter capacitor group GCA2.

[0033] In a further embodiment, the charging buffer circuit 20 includes a buffer contactor KP2, a buffer resistor R1 and a resettable fuse SF1. The buffer resistor R1 and the resettable fuse SF1 are connected in parallel to the buffer contactor KP2. One end of the buffer contactor KP2 is electrically connected to the absorption capacitor C4, and the other end is electrically connected to the inverter filter capacitor group through the filter inductor IND1. The buffer contactor KP2, the buffer resistor R1 and the resettable fuse SF1 constitute a charging buffer circuit 20 for the inverter filter capacitor group GCA2. The function of the buffer circuit is to eliminate the current impact on the input circuit and the rectifier bridge when power is turned on, and reduce the impact and interference on the power grid.

[0034] Reference Figure 4 , the DC output module 3 includes a DC input terminal TM2, an inverter IGBT high-frequency absorption capacitor C1, an inverter IGBT high-frequency absorption capacitor C2, a full-bridge inverter circuit 30, a DC isolation rectifier output module 31 and a DC output terminal TM3;

[0035] The input end of the DC input terminal TM2 is electrically connected to the output end of the DC bus power supply module 2, and the output end of the DC input terminal TM2 is electrically connected to the inverter IGBT high-frequency absorption capacitor C1, the inverter IGBT high-frequency absorption capacitor C2 and the input end of the full-bridge inverter circuit 30 in sequence to realize the medium-frequency AC conversion output, and the output end of the full-bridge inverter circuit 30 is electrically connected to the input end of the DC isolation rectifier output module 31 to convert the medium-frequency AC into DC current output, and the output end of the DC isolation rectifier output module 31 is electrically connected to the DC output terminal TM3.

[0036] In a further embodiment, the full-bridge inverter circuit 30 includes four insulated gate bipolar transistors IGBT1-IGBT4, and the first circuit formed by the insulated gate bipolar transistors IGBT1 and IGBT2 in series is connected in parallel with the second circuit formed by the insulated gate bipolar transistors IGBT3 and IGBT4 in series, so that the full-bridge inverter circuit 30 completes the conversion of DC into medium-frequency AC output under the digital control of DSP+CPLD. During the inverter output, the IGBT turn-on time of each half cycle can be adjusted to achieve adjustable inverter output voltage, which is used to adjust the output current and output voltage.

[0037] In a further embodiment, the DC isolation and rectification output module 31 includes a DC isolation capacitor CAP1, an intermediate frequency isolation transformer TR1, an intermediate frequency rectifier bridge BG2, an output smoothing reactor IND2, a large-capacity output capacitor CAP3 and a current detection shunt FL1;

[0038] The DC blocking capacitor CAP1 is electrically connected between the output end of the full-bridge inverter circuit 30 and the input end of the intermediate frequency isolation transformer TR1 to isolate the DC component of the inverter output and prevent the transformer from being magnetically saturated; the output end of the intermediate frequency isolation transformer TR1 is electrically connected to the intermediate frequency rectifier bridge BG2, and a plurality of taps N1, N2, and N3 are designed on the intermediate frequency isolation transformer TR1 to change the turns ratio connection of the transformer, thereby changing the secondary current and voltage of the transformer, and at the same time playing the role of output isolation. At the same time, the intermediate frequency rectifier bridge BG2 adopts a plurality of fast diodes for rectification to rectify the intermediate frequency current output by the transformer into a DC current; one of the output ends of the intermediate frequency rectifier bridge BG2 is electrically connected in sequence to the output smoothing reactance IND2 and the large-capacity output capacitor CAP3, and a large-capacity electrolytic capacitor is adopted; the current detection shunt FL1 is connected in parallel with the output end of the intermediate frequency isolation transformer TR1 to detect the output DC current after rectification by the intermediate frequency rectifier bridge BG2.

[0039] Reference Figure 3-Figure 5 When the DC bus power supply module 2 and multiple DC output modules 3 of the multi-channel modular DC power supply are electrically connected, the output terminal of one DC bus power supply module 2 can be connected to the DC output modules 3 of multiple channels, and each DC output module 3 has an independent output circuit and control circuit, which can realize the independent adjustable output function of multiple modules.

[0040] In a further embodiment, a plurality of air cooling mechanisms corresponding to the DC bus power supply module 2 and the DC output module 3 are installed on the mounting frame 1. The air cooling mechanism may be a fan. A fan is installed on each module chassis for independent cooling without affecting each other.

[0041] The technical effects of the multi-channel modular DC power supply structure of the utility model are as follows:

[0042] 1. It can be used in DC heating furnaces with multi-temperature zone requirements. It can realize independent power-on heating of multiple resistance loads, and can also realize power-on heating of multiple areas of the same resistance load.

[0043] 2. It can be used in heat treatment situations where multiple temperature zone control requirements are required. For heat treatment of some large special-shaped workpieces, multiple resistance heating belts are laid on the surface of the workpiece for heating. Each heating belt is responsible for heating an area and can independently control the temperature of the area to ensure the temperature uniformity of the entire special-shaped workpiece. At this time, a multi-channel modular DC power supply structure device can be used.

[0044] The above is only a preferred embodiment of the utility model, and is not any formal or substantial limitation of the utility model. It should be pointed out that ordinary technicians in this technical field can make some improvements and supplements without departing from the utility model, and these improvements and supplements should also be regarded as the protection scope of the utility model. Any technician familiar with this profession can make some changes, modifications and equivalent changes made by using the technical content disclosed above without departing from the spirit and scope of the utility model, which are all equivalent embodiments of the utility model; at the same time, any changes, modifications and evolutions of any equivalent changes made to the above embodiments based on the essential technology of the utility model are still within the scope of the technical solution of the utility model.

Claims

1. A multi-channel modular DC power supply structure, characterized in that: The invention comprises a mounting frame (1), a DC bus power supply module (2) and a DC output module (3), wherein the DC bus power supply module (2) is detachably arranged in the mounting frame (1), and a plurality of DC output modules (3) are detachably arranged and separately arranged in the mounting frame (1), and the DC output modules (3) are all electrically connected to the DC bus power supply module (2).

2. A multi-channel modular DC power supply structure as claimed in claim 1, characterized in that: The DC bus power supply module (2) comprises a three-phase power supply, a circuit breaker K1, a three-phase rectifier bridge BD1, an absorption capacitor C4, an inverter filter capacitor group GCA2 and a DC bus output terminal TM1; The output end of the three-phase power supply is electrically connected to the rectifier signal input end of the three-phase rectifier bridge BD1 through the circuit breaker K1, and the output end of the three-phase rectifier bridge BD1 is electrically connected to the absorption capacitor C4, the inverter filter capacitor group GCA2 and the DC bus output terminal TM1 in sequence, and a charging buffer circuit (20) is connected in series between the absorption capacitor C4 and the inverter filter capacitor group GCA2.

3. A multi-channel modular DC power supply structure as claimed in claim 2, characterized in that: The charging buffer circuit (20) comprises a buffer contactor KP2, a buffer resistor R1 and a resettable fuse SF1. The buffer resistor R1 and the resettable fuse SF1 are connected in parallel to the buffer contactor KP2. One end of the buffer contactor KP2 is electrically connected to the absorption capacitor C4, and the other end is electrically connected to the inverter filter capacitor group through the filter inductor IND1.

4. A multi-channel modular DC power supply structure as claimed in claim 1, characterized in that: The DC output module (3) comprises a DC input terminal TM2, an inverter IGBT high-frequency absorption capacitor C1, an inverter IGBT high-frequency absorption capacitor C2, a full-bridge inverter circuit (30), a DC isolation rectifier output module (31) and a DC output terminal TM3; The DC input terminal TM2 input end is electrically connected to the DC bus power supply module (2) output end, the DC input terminal TM2 output end is electrically connected to the inverter IGBT high-frequency absorption capacitor C1, the inverter IGBT high-frequency absorption capacitor C2 and the full-bridge inverter circuit (30) input end in sequence to achieve medium-frequency AC conversion output, the full-bridge inverter circuit (30) output end is electrically connected to the DC isolation rectifier output module (31) input end to convert the medium-frequency AC into DC current output, and the DC isolation rectifier output module (31) output end is electrically connected to the DC output terminal TM3.

5. A multi-channel modular DC power supply structure as claimed in claim 4, characterized in that: The full-bridge inverter circuit (30) comprises four insulated gate bipolar transistors IGBT1-IGBT4, wherein a first circuit formed by the insulated gate bipolar transistors IGBT1 and IGBT2 connected in series is connected in parallel with a second circuit formed by the insulated gate bipolar transistors IGBT3 and IGBT4 connected in series.

6. A multi-channel modular DC power supply structure as claimed in claim 4, characterized in that: The DC blocking and rectifying output module (31) comprises a DC blocking capacitor CAP1, an intermediate frequency isolation transformer TR1, an intermediate frequency rectifier bridge BG2, an output smoothing reactor IND2, a large-capacity output capacitor CAP3 and a current detection shunt FL1; the DC blocking capacitor CAP1 is electrically connected between the output end of the full-bridge inverter circuit (30) and the input end of the intermediate frequency isolation transformer TR1 to isolate the DC component; The output end of the intermediate frequency isolation transformer TR1 is electrically connected to the intermediate frequency rectifier bridge BG2 to rectify the intermediate frequency current output by the transformer into a direct current; One of the output ends of the intermediate frequency rectifier bridge BG2 is electrically connected to the output smoothing reactor IND2 and the large-capacity output capacitor CAP3 in sequence; the current detection shunt FL1 is connected in parallel with the output end of the intermediate frequency isolation transformer TR1 to detect the output DC current after rectification by the intermediate frequency rectifier bridge BG2.

7. A multi-channel modular DC power supply structure as claimed in claim 1, characterized in that: The DC bus power supply module (2) and the DC output module (3) both adopt independent drawer-type chassis.

8. A multi-channel modular DC power supply structure as claimed in claim 1, characterized in that: The installation frame (1) is provided with a plurality of air cooling mechanisms corresponding to the DC bus power supply module (2) and the DC output module (3).

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