Three-phase power supply circuit and three-phase equipment

Abstract

The invention discloses a three-phase power supply circuit and three-phase equipment, and relates to the technical field of power supplies, and the disclosed three-phase power supply circuit comprises a three-phase power supply which supplies three-phase AC voltage; the input end of the first rectifying circuit is connected with the first output end of the three-phase power supply, and the first rectifying circuit is used for rectifying the three-phase alternating-current voltage into first voltage; the input end of the second rectifying circuit is connected with the second output end of the three-phase power supply, and the second rectifying circuit rectifies the three-phase alternating-current voltage into second voltage; the input end of the coupling circuit is connected with the output end of the second rectifying circuit, and the coupling circuit couples an alternating current signal in the second voltage; the first input end of the third rectifying circuit is connected with the first output end of the first rectifying circuit, the second input end of the third rectifying circuit is connected with the output end of the coupling circuit, and the third rectifying circuit is used for rectifying a power supply between the first rectifying circuit and the second rectifying circuit so as to output a low-voltage direct-current power supply; therefore, a stable and reliable auxiliary power supply is provided for the three-phase zero-line-free circuit.

Description

Technical Field

[0001] The present application relates to the field of power supply technology, and in particular to a three-phase power supply circuit and a three-phase device. Background Art

[0002] In the power system, the three-phase circuit without neutral wire is a special circuit structure, which is mainly composed of three-phase power supply, load and corresponding control equipment. Compared with the traditional three-phase four-wire circuit, the three-phase circuit without neutral wire omits the neutral wire, thereby simplifying the circuit structure, reducing the cost, and performing well in certain specific applications such as high-voltage transmission, industrial power systems, etc.

[0003] However, the three-phase circuit without neutral line faces some challenges in providing auxiliary power. The auxiliary power supply is an indispensable part of the power system. It is usually used to provide a stable power supply for control equipment, sensors, relays, etc. to ensure the normal operation of the whole system. In the traditional three-phase four-wire circuit, the neutral line can be used as the reference potential of the auxiliary power supply, but in the three-phase circuit without neutral line, due to the lack of neutral line, it becomes relatively complicated to achieve a stable auxiliary power supply.

[0004] At present, the following methods are mainly used for the auxiliary power supply design of three-phase circuits without neutral line: one is to use one phase of the three-phase power supply as the reference potential, but this method may cause the auxiliary power supply voltage to be unstable when the power supply is unbalanced or the load changes; the second is to use an independent power supply module, which can provide a stable auxiliary power supply but increases the complexity and cost of the system. Summary of the invention

[0005] The main purpose of this application is to provide a three-phase power supply circuit and a three-phase device, aiming to solve the technical problem of how to provide a stable and reliable auxiliary power supply for a three-phase circuit without a neutral line without increasing the complexity and cost of the system.

[0006] To achieve the above object, the present application proposes a three-phase power supply circuit, the three-phase power supply circuit comprising:

[0007] A three-phase power supply, the three-phase power supply is used to supply a three-phase alternating current voltage;

[0008] a first rectifier circuit, wherein an input end of the first rectifier circuit is connected to a first output end of a three-phase power supply, and the first rectifier circuit is used to rectify the three-phase AC voltage into a first voltage;

[0009] a second rectifier circuit, wherein an input end of the second rectifier circuit is connected to a second output end of the three-phase power supply, and the second rectifier circuit is used to rectify the three-phase AC voltage into a second voltage;

[0010] a coupling circuit, wherein an input end of the coupling circuit is connected to an output end of the second rectifier circuit, and the coupling circuit is used to couple an AC signal in the second voltage;

[0011] A third rectifier circuit, wherein the first input end of the third rectifier circuit is connected to the first output end of the first rectifier circuit, the second input end of the third rectifier circuit is connected to the output end of the coupling circuit, and the third rectifier circuit is used to rectify the power supply between the first rectifier circuit and the second rectifier circuit to output a low-voltage DC power supply.

[0012] In one embodiment, the first rectifier circuit includes:

[0013] a first three-phase rectifier circuit, wherein an output end of the first three-phase rectifier circuit is connected to an output end of the three-phase power supply, and the first three-phase rectifier circuit is used to rectify the three-phase AC voltage into a first voltage;

[0014] A first filter circuit, wherein the input end of the first filter circuit is connected to the output end of the first three-phase rectifier circuit, the output end of the first filter circuit is connected to the first input end of the third rectifier circuit, and the first filter circuit is used to filter out the AC signal in the first voltage.

[0015] In one embodiment, the first three-phase rectifier circuit includes:

[0016] A first diode, a second diode is connected between an anode of the first diode and ground, and a common node of the first diode and the second diode is connected to phase A of the three-phase power supply;

[0017] A third diode, a fourth diode is connected between the anode of the third diode and the ground, and a common node of the third diode and the fourth diode is connected to the B phase of the three-phase power supply;

[0018] a fifth diode, wherein a sixth diode is connected between an anode of the fifth diode and ground, and a common node of the fifth diode and the sixth diode is connected to phase C of the three-phase power supply;

[0019] A common node of the first diode, the third diode and the fifth diode is an output end of the first rectifier circuit;

[0020] The first filtering circuit comprises:

[0021] a first resistor, wherein two ends of the first resistor are connected in parallel with a first capacitor, and a first end of the first resistor is connected to a common node of the first diode, the third diode, and the fifth diode;

[0022] a second resistor, two ends of the second resistor being connected in parallel with a second capacitor, and a second end of the second resistor being grounded;

[0023] A common node between the first resistor and the second resistor is connected to a common node between the first capacitor and the second capacitor.

[0024] In one embodiment, the second rectifier circuit includes:

[0025] a seventh diode, wherein an eighth diode is connected between an anode of the seventh diode and ground, and a common node between the seventh diode and the eighth diode is connected to phase A of the three-phase power supply;

[0026] a ninth diode, wherein a tenth diode is connected between an anode of the ninth diode and ground, and a common node between the ninth diode and the tenth diode is connected to phase B of the three-phase power supply;

[0027] an eleventh diode, a twelfth diode being connected between the positive electrode of the eleventh diode and the ground, and a common node between the eleventh diode and the twelfth diode being connected to the C phase of the three-phase power supply;

[0028] A common node among the seventh diode, the ninth diode and the eleventh diode is an output end of the second rectifier circuit.

[0029] In one embodiment, the coupling circuit comprises:

[0030] A third capacitor, wherein a first end of the third capacitor is connected to the output end of the second rectifier circuit, and a second end of the third capacitor is connected to the second input end of the third rectifier circuit.

[0031] In one embodiment, the third rectifier circuit includes:

[0032] A rectifier bridge, wherein a first input end of the rectifier bridge is connected to the first rectifier circuit, and a second input end of the rectifier bridge is connected to the second rectifier circuit;

[0033] A second filter circuit, wherein a first end of the second filter circuit is connected to the first output end of the rectifier bridge, and a second end of the second filter circuit is connected to the second output end of the rectifier bridge.

[0034] In one embodiment, the second filtering circuit includes:

[0035] A fourth capacitor, wherein a first end of the fourth capacitor is connected to the first output end of the rectifier bridge, and a second end of the fourth capacitor is connected to the second output end of the rectifier bridge.

[0036] In one embodiment, the three-phase power supply is a three-phase three-wire power supply.

[0037] In one embodiment, it further includes:

[0038] a load circuit, wherein an input end of the load circuit is connected to the second output end of the first rectifier circuit, and the load circuit is used to discharge the voltage generated by the first rectifier circuit;

[0039] The load circuit comprises:

[0040] A third resistor, wherein a first end of the third resistor is connected to the output end of the first rectifier circuit, and a second end of the third resistor is grounded.

[0041] In addition, to achieve the above objectives, the present application also proposes a three-phase device, which includes the three-phase power supply circuit as described above.

[0042] The embodiment of the present invention supplies a three-phase AC voltage through a three-phase power supply, and then connects a first rectifier circuit and a second rectifier circuit to rectify the three-phase AC voltage into a first voltage and a second voltage respectively, and then uses a coupling circuit to couple the AC signal in the second voltage, and finally rectifies the first voltage and the coupled second voltage through a third rectifier circuit to output a low-voltage DC power supply, thereby providing a stable and reliable auxiliary power supply for a three-phase circuit without a neutral line. The circuit structure is simple, does not require an additional power module, and reduces the complexity and cost of the system. BRIEF DESCRIPTION OF THE DRAWINGS

[0043] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the present application and, together with the description, serve to explain the principles of the present application.

[0044] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, for ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative labor.

[0045] Figure 1 It is a structural schematic diagram of an embodiment of a three-phase power supply circuit of the present invention;

[0046] Figure 2 It is a structural schematic diagram of another embodiment of the three-phase power supply circuit of the present invention;

[0047] Figure 3 It is a structural schematic diagram of another embodiment of the three-phase power supply circuit of the present invention;

[0048] Figure 4 It is a structural schematic diagram of another embodiment of the three-phase power supply circuit of the present invention;

[0049] Figure 5It is the principle diagram of the three-phase power supply circuit of the present invention.

[0050] Description of Figure Numbers:

[0051]

[0052]

[0053] The purpose, features and advantages of this application will be further described in conjunction with the embodiments and with reference to the accompanying drawings. DETAILED DESCRIPTION

[0054] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0055] It should be noted that all directional indications in the embodiments of the present invention (such as up, down, left, right, front, back, etc.) are only used to explain the relative position relationship, movement status, etc. between the components under a certain specific posture (as shown in the accompanying drawings). If the specific posture changes, the directional indication will also change accordingly.

[0056] In addition, the descriptions of "first", "second", etc. in the present invention are only used for descriptive purposes and cannot be understood as indicating or implying their relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In addition, the technical solutions between the various embodiments can be combined with each other, but they must be based on the ability of ordinary technicians in the field to implement them. When the combination of technical solutions is contradictory or cannot be implemented, it should be deemed that such a combination of technical solutions does not exist and is not within the scope of protection required by the present invention.

[0057] In one embodiment of the present invention, Figure 1 As shown, this embodiment provides a three-phase power supply 100 circuit, the circuit comprising the three-phase power supply 100, a first rectifier circuit 200, a second rectifier circuit 300, a coupling circuit 400 and a third rectifier circuit 500, wherein:

[0058] The three-phase power supply 100 is used to supply a three-phase AC voltage; the input end of the first rectifier circuit 200 is connected to the first output end of the three-phase power supply 100, and the first rectifier circuit 200 is used to rectify the three-phase AC voltage into a first voltage; the input end of the second rectifier circuit 300 is connected to the second output end of the three-phase power supply 100, and the second rectifier circuit 300 is used to rectify the three-phase AC voltage into a second voltage; the input end of the coupling circuit 400 is connected to the output end of the second rectifier circuit 300, and the coupling circuit 400 is used to couple the AC signal in the second voltage; the first input end of the third rectifier circuit 500 is connected to the first output end of the first rectifier circuit 200, and the second input end of the third rectifier circuit 500 is connected to the output end of the coupling circuit 400, and the third rectifier circuit 500 is used to rectify the power between the first rectifier circuit 200 and the second rectifier circuit 300 to output a low-voltage DC power supply.

[0059] In this embodiment, the three-phase power supply 100 is rectified by the first rectifier circuit 200 and the second rectifier circuit 300 respectively, and the first rectifier circuit 200 is provided with a corresponding filter circuit so that the voltage rectified by the first rectifier circuit 200 is a DC voltage, while the second rectifier circuit 300 is not provided with a corresponding filter circuit so that the second voltage includes a DC signal and an AC signal, and then the AC signal in the second voltage is coupled out by the coupling circuit 400, and finally the first voltage and the coupled second voltage are rectified by the third rectifier circuit 500 to output a low-voltage DC power supply. This circuit design makes full use of the characteristics of the three-phase power supply 100, realizes stable and reliable power supply without a neutral line circuit, and reduces the complexity and cost of the system at the same time, and has good practicality and economic value.

[0060] In this embodiment, the first rectifier circuit 200 and the second rectifier circuit 300 are both three-phase rectifier circuits, wherein the first rectifier circuit 200 includes a three-phase rectifier bridge composed of six diodes and a filter circuit for filtering out AC signals, and the second rectifier circuit 300 includes a three-phase rectifier bridge composed of six diodes; such an arrangement can make the first voltage output by the first rectifier circuit 200 a stable DC voltage, and the second voltage output by the second rectifier circuit 300 a mixed voltage including a DC signal and an AC signal, thereby providing the necessary signal source for the subsequent coupling circuit 400.

[0061] In this embodiment, the coupling circuit 400 may include a capacitor or an inductor, and the AC signal in the second voltage is coupled by the capacitor or the inductor to extract and transmit the AC signal, thereby providing the necessary input signal for the subsequent third rectifier circuit 500.

[0062] In this embodiment, the third rectifier circuit 500 includes a unidirectional rectifier bridge and a filter circuit for filtering out AC signals. The first voltage and the coupled second voltage are rectified by the rectifier bridge and then filtered to output a stable low-voltage DC power supply, so as to provide a stable and reliable power supply to the input end of the auxiliary power supply circuit, and provide a stable and reliable power supply for the load circuit 600, thereby reducing the complexity and cost of the system and having good practicality and economic value.

[0063] In this embodiment, the three-phase power supply 100 is a three-phase three-wire power supply.

[0064] In this embodiment, the three-phase three-wire power supply is a power supply circuit composed of three AC power supplies with a phase difference of 120 degrees. It is a circuit mode with only a live wire. Compared with the traditional three-phase four-wire power supply, the three-phase three-wire power supply omits the neutral wire and is composed of only three independent lines, corresponding to three phases. This simple line design not only reduces the cost, but also improves the reliability of the system. This power supply system is widely used in various industrial, commercial and household fields, especially in occasions requiring high power and stable voltage.

[0065] In practical applications, three-phase three-wire power supply is favored due to its unique advantages. First, it can effectively reduce line loss and energy waste while ensuring stable power supply. Secondly, since the neutral line is omitted, the three-phase three-wire power supply is easier to install and maintain, greatly reducing the difficulty and cost of operation.

[0066] In this embodiment, since some special power supply equipment or power consumption equipment only has three-phase live wires but no neutral wire, the flow of power is realized through the phase relationship between the three live wires to provide a voltage of 380V. In this circuit, since there is no neutral wire as a reference end, it cannot directly output a voltage of 220V. If it is directly rectified, the resulting DC voltage is 511V, and the voltage is too high. Since most of the flyback transformer elements or related control devices on the market currently have low withstand voltage values ​​and cannot work well under the high voltage of 511V for a long time, the direct rectification method cannot be used by weak current circuits such as auxiliary control circuits. In order to reduce the voltage of the three-phase circuit without a neutral wire for use by the auxiliary power supply, a three-phase voltage of 380V is input through the three wires of the three-phase power supply 100, and is rectified into a DC voltage of 511V, i.e., the first voltage, through a second rectifier circuit 300 having no filter capacitor to the ground. Since the second rectifier circuit 300 has no capacitance to the ground, its output is floating, so as to rectify the 380V AC voltage into a mixed voltage of AC and DC, in which the voltage of the AC part varies between 380-540V, and the frequency of the AC signal is about 300Hz. Then, the DC signal is filtered out of the voltage output by the second rectifier circuit 300 through the coupling circuit 400, and the AC signal is retained. Finally, the DC voltage output by the first rectifier circuit 200 and the voltage output by the coupled second rectifier circuit 300 are filtered through the third rectifier circuit 500. In the third rectifier circuit 500, the DC voltage output by the first rectifier circuit 200 and the voltage output by the coupled second rectifier circuit 300 are subtracted, so that the voltage output by the third rectifier circuit 500 is more than one hundred volts, and the voltage of more than one hundred volts is within the voltage range in which most flyback transformers can operate, so that the voltage can be rectified and reduced to provide a stable and reliable power supply.

[0067] The technical solution of the present invention supplies a three-phase AC voltage through a three-phase power supply 100, and then connects a first rectifier circuit 200 and a second rectifier circuit 300 to rectify the three-phase AC voltage into a first voltage and a second voltage respectively, and then uses a coupling circuit 400 to couple the AC signal in the second voltage, and finally rectifies the first voltage and the coupled second voltage through a third rectifier circuit 500 to output a low-voltage DC power supply, thereby providing a stable and reliable auxiliary power supply for a three-phase circuit without a neutral line. The circuit structure is simple, does not require an additional power module, and reduces the complexity and cost of the system.

[0068] Combined with reference Figure 2 As shown, further, another embodiment of the present invention provides a three-phase power supply 100 circuit, based on the above Figure 1In the embodiment shown, the first rectifier circuit 200 includes a first three-phase rectifier circuit 210 and a first filter circuit 220, wherein:

[0069] The output end of the first three-phase rectifier circuit 210 is connected to the output end of the three-phase power supply 100, and the first three-phase rectifier circuit 210 is used to rectify the three-phase AC voltage into a first voltage; the input end of the first filter circuit 220 is connected to the output end of the first three-phase rectifier circuit 210, and the output end of the first filter circuit 220 is connected to the first input end of the third rectifier circuit 500, and the first filter circuit 220 is used to filter out the AC signal in the first voltage.

[0070] In this embodiment, the first three-phase rectifier circuit 210 is a three-phase rectifier bridge composed of six diodes, which can rectify the three-phase AC voltage into a pulsating DC voltage. In order to improve the stability of the output DC voltage, the first filter circuit 220 is arranged at the output end of the first three-phase rectifier circuit 210, and is used to filter out the AC signal in the first voltage, so that the output DC voltage is more stable. In this way, through the processing of the first rectifier circuit 200, a stable DC voltage can be obtained as one of the inputs of the third rectifier circuit 500.

[0071] In this embodiment, the first filtering circuit 220 may include components such as resistors and capacitors for filtering out ripples and noise in the DC voltage and improving the purity of the DC voltage. It can effectively rectify the input pulsating DC voltage into a stable DC voltage. By setting a filtering circuit and selecting a suitable rectifier bridge, the stability and purity of the output DC power supply can be further improved, providing a stable and reliable power supply for the load circuit 600.

[0072] Combined with reference Figure 5 As shown, further, another embodiment of the present invention provides a three-phase power supply 100 circuit, based on the above Figure 2 In the embodiment shown, the first three-phase rectifier circuit 210 includes a first diode D1, a third diode D3 and a fifth diode D5, wherein:

[0073] A second diode D2 is connected between the anode of the first diode D1 and the ground, and a common node of the first diode D1 and the second diode D2 is connected to the A phase of the three-phase power supply 100; a fourth diode D4 is connected between the anode of the third diode D3 and the ground, and a common node of the third diode D3 and the fourth diode D4 is connected to the B phase of the three-phase power supply 100; a sixth diode D6 is connected between the anode of the fifth diode D5 and the ground, and a common node of the fifth diode D5 and the sixth diode D6 is connected to the C phase of the three-phase power supply 100; the common node of the first diode D1, the third diode D3 and the fifth diode D5 is the output end of the first rectifier circuit 200.

[0074] In the present embodiment, the first three-phase rectifier circuit 210 is composed of six diodes (first diode D1 to sixth diode D6), which are connected in a specific manner to rectify the three-phase AC voltage into a pulsating DC voltage. Specifically, the positive poles of the first diode D1, the third diode D3 and the fifth diode D5 are respectively connected to the A, B, and C phases of the three-phase power supply 100, and their negative poles are grounded through the second diode D2, the fourth diode D4 and the sixth diode D6. This connection method forms three independent rectifier branches, each branch consisting of two diodes, which are alternately turned on to rectify the AC voltage of the corresponding phase into a DC voltage. The common node of the three rectifier branches is the output end of the first rectifier circuit 200, which outputs a pulsating DC voltage.

[0075] By providing the first three-phase rectifier circuit 210, this embodiment realizes effective rectification of the three-phase AC voltage and obtains a pulsating DC voltage as the input of the subsequent circuit. At the same time, due to the use of a three-phase rectifier bridge composed of six diodes, the rectification efficiency is improved and the output DC voltage is more stable.

[0076] In practical applications, the design of this three-phase rectifier bridge can be adjusted and optimized according to specific needs. For example, the rectification efficiency and the stability of the output DC voltage can be improved by changing the type and number of diodes, adjusting the connection method, etc.

[0077] In this embodiment, the first filter circuit 220 includes a first resistor R1 and a second resistor R2, wherein:

[0078] A first capacitor C3 is connected in parallel at both ends of the first resistor R1, and a first end of the first resistor R1 is connected to a common node of the first diode D1, the third diode D3, and the fifth diode D5; a second capacitor C4 is connected in parallel at both ends of the second resistor R2, and a second end of the second resistor R2 is grounded; a common node of the first resistor R1 and the second resistor R2 is connected to a common node of the first capacitor C3 and the second capacitor C4.

[0079] In the present embodiment, the first filter circuit 220 is composed of a first resistor R1, a second resistor R2, a first capacitor C3 and a second capacitor C4. The first capacitor C3 is connected in parallel at both ends of the first resistor R1 to form an RC filter circuit for filtering high-frequency noise and ripples in the DC voltage. The second capacitor C4 is connected in parallel at both ends of the second resistor R2 to form another RC filter circuit for filtering low-frequency noise and ripples in the DC voltage. The first end of the first resistor R1 is connected to the common node of the first diode D1, the third diode D3 and the fifth diode D5, that is, connected to the output end of the first three-phase rectifier circuit 210, and receives the pulsating DC voltage as input. The second end of the second resistor R2 is grounded to provide a reference potential for the filter circuit. By setting the first filter circuit 220, the present embodiment further improves the stability and purity of the output DC voltage. The RC filter circuit can effectively filter out the noise and ripples in the DC voltage, making the output DC voltage smoother and more stable. Meanwhile, the resistance values ​​of the first resistor R1 and the second resistor R2 and the capacitance values ​​of the first capacitor C3 and the second capacitor C4 can be adjusted and optimized according to specific requirements to achieve the best filtering effect.

[0080] In practical applications, the design of this filter circuit can be adjusted according to specific application scenarios and load requirements. For example, in situations where a higher-precision power supply is required, a larger-capacity capacitor and a higher-precision resistor can be used to improve the filtering effect. In addition, other types of filter circuits, such as LC filter circuits, π-type filter circuits, etc., can also be used to meet different needs.

[0081] Combined with reference Figure 5 As shown, further, another embodiment of the present invention provides a three-phase power supply 100 circuit, based on the above Figure 1 In the embodiment shown, the second rectifier circuit 300 includes a seventh diode D7, a ninth diode D9 and an eleventh diode D11, wherein:

[0082] An eighth diode D8 is connected between the anode of the seventh diode D7 and the ground, and the common node of the seventh diode D7 and the eighth diode D8 is connected to the A phase of the three-phase power supply 100; a tenth diode D10 is connected between the anode of the ninth diode D9 and the ground, and the common node of the ninth diode D9 and the tenth diode D10 is connected to the B phase of the three-phase power supply 100; a twelfth diode D12 is connected between the anode of the eleventh diode D11 and the ground, and the common node of the eleventh diode D11 and the twelfth diode D12 is connected to the C phase of the three-phase power supply 100; the common node of the seventh diode D7, the ninth diode D9 and the eleventh diode D11 is the output end of the second rectifier circuit 300.

[0083] In this embodiment, the second rectifier circuit 300 is also composed of six diodes (the seventh diode D7 to the twelfth diode D12), forming a structure similar to the first three-phase rectifier circuit 210. The anodes of the seventh diode D7, the ninth diode D9 and the eleventh diode D11 are respectively connected to the three phases A, B and C of the three-phase power supply 100, and their cathodes are grounded through the eighth diode D8, the tenth diode D10 and the twelfth diode D12. This connection mode enables the second rectifier circuit 300 to rectify the three-phase AC voltage into another pulsating DC voltage.

[0084] Similar to the first rectifier circuit 200 , the output end of the second rectifier circuit 300 is a common node of the seventh diode D7 , the ninth diode D9 and the eleventh diode D11 , and the output pulsating DC voltage can be used as an input of other circuits or modules.

[0085] However, different from the first rectifier circuit 200 , the second rectifier circuit 300 is not provided with a corresponding filter circuit to provide a voltage signal that is a mixture of a DC signal and an AC signal.

[0086] In practical applications, the design of the second rectifier circuit 300 can also be optimized and adjusted according to actual needs. For example, the rectification efficiency and the stability of the output DC voltage can be improved by changing the type and quantity of diodes, adjusting the connection mode, etc.

[0087] Combined with reference Figure 5 As shown, further, the present invention also provides a three-phase power supply 100 circuit according to an embodiment of the present invention. Figure 1 In the embodiment shown, the coupling circuit 400 includes a third capacitor C5, wherein:

[0088] A first end of the third capacitor C5 is connected to the output end of the second rectifier circuit 300 , and a second end of the third capacitor C5 is connected to the second input end of the third rectifier circuit 500 .

[0089] In this embodiment, the coupling circuit 400 is implemented by using a third capacitor C5. The first end of the third capacitor C5 is connected to the output end of the second rectifier circuit 300, that is, it receives the mixed voltage of the pulsating DC voltage and the AC signal output by the second rectifier circuit 300. The second end of the third capacitor C5 is connected to the second input end of the third rectifier circuit 500, and transmits the mixed voltage to the third rectifier circuit 500 for processing.

[0090] By setting the third capacitor C5, this embodiment achieves coupling of the mixed voltage output by the second rectifier circuit 300, so that it can be used as the input of the third rectifier circuit 500. The capacity of the third capacitor C5 can be adjusted according to specific needs to achieve appropriate coupling and transmission of the mixed voltage.

[0091] In practical applications, other factors also need to be considered in the design of the coupling circuit 400. For example, the withstand voltage and temperature characteristics of the third capacitor C5 need to be considered to ensure its stability and reliability under different working conditions. In addition, the layout and wiring of the circuit also need to be considered to reduce the loss and interference during signal transmission.

[0092] Combined with reference Figure 3 As shown, further, another embodiment of the present invention provides a three-phase power supply 100 circuit, based on the above Figure 1 In the embodiment shown, the third rectifier circuit 500 includes a rectifier bridge 510 and a second filter circuit 520, wherein:

[0093] The first input end of the rectifier bridge 510 is connected to the first rectifier circuit 200, and the second input end of the rectifier bridge 510 is connected to the second rectifier circuit 300; the first end of the second filter circuit 520 is connected to the first output end of the rectifier bridge 510, and the second end of the second filter circuit 520 is connected to the second output end of the rectifier bridge 510.

[0094] In this embodiment, the third rectifier circuit 500 uses a combination of a single-phase rectifier bridge 510 and a second filter circuit 520 to further process the voltage output by the first rectifier circuit 200 and the second rectifier circuit 300. The first input end of the rectifier bridge 510 is connected to the first rectifier circuit 200 to receive the stable DC voltage output by the first rectifier circuit 200. The second input end of the rectifier bridge 510 is connected to the second rectifier circuit 300 to receive the AC voltage output by the coupling circuit 400. The voltages of the two input ends are rectified and combined by the rectifier bridge 510 to obtain a more stable low-voltage DC voltage.

[0095] The output end of the rectifier bridge 510 is connected to the second filter circuit 520. The design of the second filter circuit 520 is similar to the first filter circuit 220, and is composed of a resistor and a capacitor, and is used to filter out noise and ripples in the DC voltage. By setting the second filter circuit 520, the present embodiment further improves the stability and purity of the output DC voltage.

[0096] In practical applications, the parameters of the rectifier bridge 510 and the second filter circuit 520 need to be adjusted according to specific requirements. For example, it is necessary to select a suitable rectifier bridge 510 model and filter circuit parameters according to factors such as the input voltage amplitude, frequency, and load requirements to achieve the best rectification and filtering effects.

[0097] Combined with reference Figure 5 As shown, further, another embodiment of the present invention provides a three-phase power supply 100 circuit, based on the above Figure 3 In the embodiment shown, the second filtering circuit 520 includes a fourth capacitor C6, wherein:

[0098] A first end of the fourth capacitor C6 is connected to the first output end of the rectifier bridge 510 , and a second end of the fourth capacitor C6 is connected to the second output end of the rectifier bridge 510 .

[0099] In this embodiment, the second filter circuit 520 is implemented by using a fourth capacitor C6. A first end of the fourth capacitor C6 is connected to a first output end of the rectifier bridge 510, and a second end is connected to a second output end of the rectifier bridge 510, forming a simple filter circuit for filtering out ripples and noise in the output DC voltage of the rectifier bridge 510. By providing the fourth capacitor C6, this embodiment further improves the smoothness and stability of the output DC voltage.

[0100] In practical applications, the capacity of the fourth capacitor C6 needs to be adjusted according to specific needs. A capacitor with too small a capacity may not be able to effectively filter out ripples and noise, while a capacitor with too large a capacity may increase the complexity and cost of the circuit. Therefore, it is necessary to select an appropriate capacity of the fourth capacitor C6 according to the actual working environment and load requirements to achieve the best filtering effect.

[0101] In addition, in order to improve the filtering effect, other components such as inductors and resistors may be added to the second filtering circuit 520 to form a more complex filtering network. The selection and combination of these components also need to be optimized and adjusted according to specific needs to achieve the best filtering effect.

[0102] Combined with reference Figure 4 As shown, further, another embodiment of the present invention provides a three-phase power supply 100 circuit, based on the above Figure 1 The illustrated embodiment further comprises a load circuit 600, wherein:

[0103] An input end of the load circuit 600 is connected to a second output end of the first rectifier circuit 200 , and the load circuit 600 is used to discharge the voltage generated by the first rectifier circuit 200 .

[0104] In this embodiment, the load circuit 600 is used to discharge the voltage generated by the first rectifier circuit 200. Specifically, the input end of the load circuit 600 is connected to the second output end of the first rectifier circuit 200, so that when the first rectifier circuit 200 generates a voltage, the voltage can be discharged through the load circuit 600, thereby protecting other components in the circuit from being damaged by excessive voltage.

[0105] The design of the load circuit 600 needs to take into account the voltage and current it can withstand, as well as its heat dissipation capability. In practical applications, the load circuit 600 can be a simple resistor or a complex electronic circuit, depending on the working environment and requirements of the circuit.

[0106] In addition, in order to further improve the reliability and stability of the circuit, some protection elements, such as fuses, thermistors, etc., may be added to the load circuit 600 to promptly cut off the circuit when an abnormality occurs in the circuit to prevent damage to other elements.

[0107] The load circuit 600 includes a third resistor R3, wherein:

[0108] A first end of the third resistor R3 is connected to the output end of the first rectifier circuit 200 , and a second end of the third resistor R3 is grounded.

[0109] In this embodiment, the load circuit 600 can be a simple circuit including a third resistor R3. The first end of the third resistor R3 is connected to the output end of the first rectifier circuit 200, so that when the first rectifier circuit 200 generates a voltage, the voltage can be discharged through the third resistor R3. The second end of the third resistor R3 is grounded to form a closed current loop, ensuring that the current can flow back to the ground smoothly, thereby protecting other components in the circuit from damage by excessive voltage.

[0110] The resistance value of the third resistor R3 needs to be adjusted according to specific needs. A resistor with too small a resistance may cause excessive current, thereby damaging other components; while a resistor with too large a resistance may not be able to effectively discharge the voltage and cannot play a protective role. Therefore, it is necessary to select an appropriate resistance value of the third resistor R3 according to the actual working environment and load requirements to achieve the best discharge effect.

[0111] The present invention also proposes a three-phase device, which includes a three-phase power supply circuit. The specific structure of the three-phase power supply circuit refers to the above embodiment. Since the three-phase device adopts all the technical solutions of all the above embodiments, it at least has all the beneficial effects brought by the technical solutions of the above embodiments, which will not be repeated here one by one.

[0112] The above descriptions are only some embodiments of the present application, and are not intended to limit the patent scope of the present application. All equivalent structural changes made using the contents of the present application specification and drawings under the technical concept of the present application, or direct / indirect applications in other related technical fields are included in the patent protection scope of the present application.

Claims

1. A three-phase power supply circuit, characterized in that: The circuit comprises: A three-phase power supply, the three-phase power supply is used to supply a three-phase alternating current voltage; a first rectifier circuit, wherein an input end of the first rectifier circuit is connected to a first output end of a three-phase power supply, and the first rectifier circuit is used to rectify the three-phase AC voltage into a first voltage; a second rectifier circuit, wherein an input end of the second rectifier circuit is connected to a second output end of the three-phase power supply, and the second rectifier circuit is used to rectify the three-phase AC voltage into a second voltage; a coupling circuit, wherein an input end of the coupling circuit is connected to an output end of the second rectifier circuit, and the coupling circuit is used to couple an AC signal in the second voltage; A third rectifier circuit, wherein the first input end of the third rectifier circuit is connected to the first output end of the first rectifier circuit, the second input end of the third rectifier circuit is connected to the output end of the coupling circuit, and the third rectifier circuit is used to rectify the power supply between the first rectifier circuit and the second rectifier circuit to output a low-voltage DC power supply.

2. The three-phase power supply circuit according to claim 1, characterized in that: The first rectifier circuit comprises: a first three-phase rectifier circuit, wherein an output end of the first three-phase rectifier circuit is connected to an output end of the three-phase power supply, and the first three-phase rectifier circuit is used to rectify the three-phase AC voltage into a first voltage; A first filter circuit, wherein the input end of the first filter circuit is connected to the output end of the first three-phase rectifier circuit, the output end of the first filter circuit is connected to the first input end of the third rectifier circuit, and the first filter circuit is used to filter out the AC signal in the first voltage.

3. The three-phase power supply circuit according to claim 2, characterized in that: The first three-phase rectifier circuit comprises: A first diode, a second diode is connected between an anode of the first diode and ground, and a common node of the first diode and the second diode is connected to phase A of the three-phase power supply; A third diode, a fourth diode is connected between the anode of the third diode and the ground, and a common node of the third diode and the fourth diode is connected to the B phase of the three-phase power supply; a fifth diode, wherein a sixth diode is connected between an anode of the fifth diode and ground, and a common node of the fifth diode and the sixth diode is connected to phase C of the three-phase power supply; A common node of the first diode, the third diode and the fifth diode is an output end of the first rectifier circuit; The first filtering circuit comprises: a first resistor, wherein two ends of the first resistor are connected in parallel with a first capacitor, and a first end of the first resistor is connected to a common node of the first diode, the third diode, and the fifth diode; a second resistor, two ends of the second resistor being connected in parallel with a second capacitor, and a second end of the second resistor being grounded; A common node between the first resistor and the second resistor is connected to a common node between the first capacitor and the second capacitor.

4. The three-phase power supply circuit according to claim 1, characterized in that: The second rectifier circuit comprises: a seventh diode, wherein an eighth diode is connected between an anode of the seventh diode and ground, and a common node between the seventh diode and the eighth diode is connected to phase A of the three-phase power supply; a ninth diode, wherein a tenth diode is connected between an anode of the ninth diode and ground, and a common node between the ninth diode and the tenth diode is connected to phase B of the three-phase power supply; an eleventh diode, a twelfth diode being connected between the positive electrode of the eleventh diode and the ground, and a common node between the eleventh diode and the twelfth diode being connected to the C phase of the three-phase power supply; A common node among the seventh diode, the ninth diode and the eleventh diode is an output end of the second rectifier circuit.

5. The three-phase power supply circuit according to claim 1, characterized in that: The coupling circuit comprises: A third capacitor, wherein a first end of the third capacitor is connected to the output end of the second rectifier circuit, and a second end of the third capacitor is connected to the second input end of the third rectifier circuit.

6. The three-phase power supply circuit according to claim 1, characterized in that: The third rectifier circuit comprises: A rectifier bridge, wherein a first input end of the rectifier bridge is connected to the first rectifier circuit, and a second input end of the rectifier bridge is connected to the second rectifier circuit; A second filter circuit, wherein a first end of the second filter circuit is connected to the first output end of the rectifier bridge, and a second end of the second filter circuit is connected to the second output end of the rectifier bridge.

7. The three-phase power supply circuit according to claim 6, characterized in that: The second filtering circuit comprises: A fourth capacitor, wherein a first end of the fourth capacitor is connected to the first output end of the rectifier bridge, and a second end of the fourth capacitor is connected to the second output end of the rectifier bridge.

8. The three-phase power supply circuit according to claim 1, characterized in that: The three-phase power supply is a three-phase three-wire power supply.

9. The three-phase power supply circuit according to claim 1, characterized in that: Also includes: a load circuit, wherein an input end of the load circuit is connected to the second output end of the first rectifier circuit, and the load circuit is used to discharge the voltage generated by the first rectifier circuit; The load circuit comprises: A third resistor, wherein a first end of the third resistor is connected to the output end of the first rectifier circuit, and a second end of the third resistor is grounded.

10. A three-phase device, characterized in that: The three-phase device comprises a three-phase power supply circuit as claimed in any one of claims 1 to 9.

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