Power consumption control circuit and three-phase power supply

Abstract

The application provides a power consumption control circuit and a three-phase power supply, and relates to the technical field of three-phase power supply. The three-phase power supply comprises a power conversion circuit and a power consumption control circuit. The power conversion circuit outputs a working electrical signal when soft start is completed. The power consumption control circuit comprises three-phase power supply lines, a first phase switching circuit and a second phase switching circuit. The output ends of the three-phase power supply lines are connected with the power conversion circuit. The first phase switching circuit and the second phase switching circuit are connected in series on the corresponding phase power supply line. The first phase switching circuit is used for receiving an external control signal to make the first phase power supply line and the power conversion circuit form a current loop, and the first phase switching circuit and the power conversion circuit enter a soft start state. The first phase switching circuit is also used for receiving the working electrical signal to enter a full conduction state. At least the second phase switching circuit is used for receiving the working electrical signal to fully conduct the corresponding phase power supply line and the power conversion circuit, and the three-phase power supply lines and the power conversion circuit are fully conducted. The application can reduce the circuit complexity.

Description

Technical Field

[0001] This application relates to the field of three-phase electrical technology, and in particular to a power consumption control circuit and a three-phase power supply. Background Technology

[0002] In related technologies, power conversion circuits need to enter a soft-start state before entering the working state. Soft-start can limit the charging current, thereby reducing the impact of the large charging current at startup on the downstream load.

[0003] When the power conversion circuit is a three-phase three-wire circuit, two switching circuits are typically required on each of the two-phase power supply lines. External control signals must control at least two of these switching circuits to soft-start the two-phase power supply lines, thus putting the power conversion circuit into a soft-start state. When the power conversion circuit is a three-phase four-wire circuit, three switching circuits are typically required on at least three phase power supply lines. External control signals must control at least three of these switching circuits to soft-start the three-phase power supply lines, thus putting the power conversion circuit into a soft-start state. The number of switching circuits controlled by the external control signals is larger, resulting in a more complex overall circuit structure. Utility Model Content

[0004] This application provides a power consumption control circuit and a three-phase power supply, which can reduce the number of switching circuits that need to be controlled by external control signals, reduce the complexity of the circuit structure, and simplify the control logic.

[0005] To address the aforementioned technical problems, this application provides a power consumption control circuit for a three-phase power supply. The three-phase power supply includes a power conversion circuit and a power consumption control circuit connected thereto. The output terminal of the power conversion circuit is connected to a load and is used to output a working electrical signal upon completion of a soft start. The power consumption control circuit includes three-phase power supply lines, a first-phase switching circuit, and a second-phase switching circuit. The input terminals of the three-phase power supply lines are respectively connected to three-phase AC signals, and their output terminals are respectively connected to the power conversion circuit. The first-phase switching circuit is connected in series on the first-phase power supply line; the second-phase switching circuit is connected in series on the second-phase power supply line. The first-phase switching circuit receives an external control signal to form a current loop between the first-phase power supply line and the power conversion circuit. When a current loop is formed, the first-phase switching circuit and the power conversion circuit enter a soft-start state. The first-phase switching circuit also receives a working electrical signal to exit the soft-start state and enter a fully conductive state. At least the second-phase switching circuit receives a working electrical signal to fully conduct the corresponding phase's power supply line and the power conversion circuit. All three phase power supply lines are fully connected to the power conversion circuit, and the power conversion circuit enters a working state.

[0006] To address the aforementioned technical problems, this application further provides a three-phase power supply, including a power conversion circuit and a power consumption control circuit as described in any of the above embodiments, wherein the power conversion circuit and the power consumption control circuit are connected.

[0007] The beneficial effects of this application are as follows: The power consumption control circuit of this application includes a three-phase power supply line, a first-phase switching circuit, and a second-phase switching circuit. The input terminals of the three-phase power supply lines are respectively connected to three-phase AC signals, and the output terminals are respectively connected to the power conversion circuit. The first-phase switching circuit is connected in series on the first-phase power supply line; the second-phase switching circuit is connected in series on the second-phase power supply line. The first-phase switching circuit is used to receive an external control signal to form a current loop between the first-phase power supply line and the power conversion circuit. When a current loop is formed, the first-phase switching circuit and the power conversion circuit enter a soft-start state. The first-phase switching circuit is also used to receive a working electrical signal to exit the soft-start state and enter a fully conductive state. At least the second-phase switching circuit is used to receive a working electrical signal to fully conduct the corresponding phase's power supply line and the power conversion circuit. All three phase power supply lines are fully conductive with the power conversion circuit, and the power conversion circuit enters the working state. The external control signal of this application only needs to control the first-phase switching circuit to enable the power conversion circuit to enter a soft-start state. Specifically, in a three-phase four-wire system, there exists a neutral line that remains fully conductive with the power conversion circuit for an extended period; or in a three-phase three-wire system, there exists another power supply line that remains fully conductive with the power conversion circuit for an extended period. The first-phase switching circuit, upon receiving an external control signal, enables the first-phase power supply line to connect with the power conversion circuit and form a current loop. This prepares the circuit for the power conversion circuit to enter a soft-start state. When the current loop is formed, the first-phase switching circuit is in a soft-start state, which limits the current within the loop, allowing the power conversion circuit to also enter a soft-start state. This reduces the impact of excessive charging current on the power conversion circuit and subsequent loads. Therefore, the above-mentioned configuration in this application reduces the number of switching circuits that need to be controlled by external control signals, lowers the complexity of the circuit structure, and simplifies the control logic. Attached Figure Description

[0008] To more clearly illustrate the technical solutions in the embodiments of this application, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort. Wherein: Figure 1 This is a schematic diagram of the circuit structure of the power consumption control circuit and the three-phase three-wire power conversion circuit of the present application in the first embodiment; Figure 2 This is a schematic diagram of the circuit structure of the power consumption control circuit and the three-phase four-wire power conversion circuit of the present application in the first embodiment; Figure 3 This is a schematic diagram of the circuit structure of the power consumption control circuit and the three-phase three-wire power conversion circuit of the present application in the second embodiment; Figure 4 This is a schematic diagram of the circuit structure of the power consumption control circuit and the three-phase three-wire power conversion circuit of the present application in the third embodiment; Figure 5 This is a schematic diagram of the circuit structure of the power consumption control circuit and the three-phase three-wire power conversion circuit of the present application in the fourth embodiment; Figure 6 This is a schematic diagram of the circuit structure of the power consumption control circuit and the three-phase four-wire power conversion circuit of the present application in the second embodiment; Figure 7 This is a schematic diagram of the circuit structure of the power consumption control circuit and the three-phase four-wire power conversion circuit of the present application in the third embodiment; Figure 8 This is a schematic diagram of the circuit structure of the power consumption control circuit and the three-phase three-wire power conversion circuit of the present application in the fifth embodiment; Figure 9 This is a schematic diagram of the circuit structure of the power consumption control circuit and the three-phase four-wire power conversion circuit of the present application in the fourth embodiment.

[0009] The reference numerals in the detailed embodiments are as follows: Three-phase AC signal A, power supply line U for the first phase, power supply line V for the second phase, power supply line W for the third phase, neutral line N, first phase switch circuit 11, second phase switch circuit 12, third phase switch circuit 13, first phase switch unit 111, soft start circuit 112, short circuit switch 113, soft start resistor R, power conversion circuit 21, first relay CH1, second relay CH2, third relay CH3, fourth relay CH4, first line capacitor C1, second line capacitor C2, third line capacitor C3. Detailed Implementation

[0010] In the following description, specific details such as particular system architectures and techniques are set forth for illustrative purposes and not for limitation, in order to provide a thorough understanding of the embodiments of this application. However, those skilled in the art will understand that this application may also be implemented in other embodiments without these specific details. In other instances, detailed descriptions of well-known systems, apparatuses, circuits, and methods have been omitted so as not to obscure the description of this application with unnecessary detail.

[0011] The terms "first," "second," etc., used in this application are used to distinguish different objects, not to describe a specific order. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover non-exclusive inclusion. It should be understood that, when used in this specification, the term "comprising" indicates the presence of the described feature, integral, step, operation, element, and / or component, but does not exclude the presence or addition of one or more other features, integrals, steps, operations, elements, components, and / or collections thereof. It should also be understood that the terminology used in this specification is for the purpose of describing particular embodiments only and is not intended to limit the application. As used in this specification, unless the context clearly indicates otherwise, the singular forms "a," "an," and "the" are intended to include the plural forms. It should also be further understood that the term "and / or," as used in this specification, refers to any combination and all possible combinations of one or more of the associated listed items, and includes such combinations.

[0012] As used in this specification, the term "if" may be interpreted, depending on the context, as "when," "once," "in response to determination," or "in response to detection." Similarly, the phrase "if determination" or "if [the described condition or event] is detected" may be interpreted, depending on the context, as "once determination," "in response to determination," "once [the described condition or event] is detected," or "in response to detection of [the described condition or event]."

[0013] It should be noted that when one element is fixed to another element, this includes fixing the element directly to the other element or fixing the element to the other element through at least one other intermediate element. When one element is connected to another element, this includes connecting the element directly to the other element or connecting the element to the other element through at least one other intermediate element.

[0014] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this application, and not all of the embodiments. Based on the embodiments of this application, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of this application.

[0015] This application first proposes a power consumption control circuit for a three-phase power supply, such as... Figures 1 to 9 As shown. The three-phase power supply includes a power conversion circuit 21 and a power consumption control circuit connected to it. The output terminal of the power conversion circuit 21 is connected to the load. Figure 1 , Figure 2As shown, the power consumption control circuit includes a three-phase power supply line, a first-phase switching circuit 11, and a second-phase switching circuit 12. The input terminals of the three-phase power supply lines are respectively connected to three-phase AC signals A, and the output terminals are respectively connected to the power conversion circuit 21. The first-phase switching circuit 11 is connected in series on the first-phase power supply line U; the second-phase switching circuit 12 is connected in series on the second-phase power supply line V. The first-phase switching circuit 11 is used to receive external control signals to form a current loop between the first-phase power supply line U and the power conversion circuit 21. When a current loop is formed, the first-phase switching circuit 11 and the power conversion circuit 21 enter a soft-start state.

[0016] The first-phase switching circuit 11 and the second-phase switching circuit 12 can control the on / off state of the power supply lines of the corresponding phases and the power conversion circuit 21. An external control signal can control the state of the first-phase switching circuit 11. When forming a current loop, the first-phase switching circuit 11 enters a soft-start state. There is a soft-start resistance value on the power supply line U of the first phase, so that the power supply line U of the first phase is not completely connected to the power conversion circuit 21. That is, when the power conversion circuit 21 switches from the off state to the soft-start state, the intensity of the instantaneous charging current can be suppressed, reducing the impact of the instantaneous charging current on the power conversion circuit 21 and the downstream load.

[0017] Specifically, the three-phase power supply line consists of three live wires. The three-phase AC signal A can come from the power grid or mains power. The three live wires are connected to the power conversion circuit 21 via the power consumption control circuit, and then connected to the load, which can supply the load with the power of the external AC power.

[0018] In one application scenario, the power conversion circuit 21 may include a rectifier bridge or other conversion circuits. The load located after the power conversion circuit 21 may include a DC bus, DC electrical equipment, etc., and there is no specific limitation. The power conversion circuit 21 can deliver the current after power conversion to the load.

[0019] In related technologies, the power conversion circuit 21 needs to enter a soft-start state before entering the operating state. Soft-start limits the charging current to reduce the impact of the large charging current during startup on the downstream load. For example... Figure 1 As shown, when the power conversion circuit 21 is a three-phase three-wire circuit, two switching circuits are usually required to be set on two phase power supply lines. The external control signal needs to control at least two switching circuits to achieve soft-start of the two phase power supply lines, so that the power conversion circuit 21 enters the soft-start state; for example... Figure 2 As shown, when the power conversion circuit 21 is a three-phase four-wire circuit, it is usually necessary to set three switching circuits on at least three phase power supply lines. The external control signal usually needs to control at least three switching circuits to soft-start the three phase power supply lines so that the power conversion circuit 21 enters the soft-start state. The number of switching circuits that the external control signal needs to control is large, and the overall circuit structure is complex.

[0020] In this embodiment, the power conversion circuit 21 can enter a soft-start state by controlling only the first-phase switching circuit 11 with an external control signal. Specifically, in a three-phase four-wire system, there is a neutral line N that is always fully conductive with the power conversion circuit 21, or in a three-phase three-wire system, there is a power supply line of another phase that is always fully conductive with the power conversion circuit 21. The first-phase switching circuit 11, upon receiving the external control signal, can connect the first-phase power supply line U with the power conversion circuit 21 to form a current loop, thus preparing the circuit for the power conversion circuit 21 to enter the soft-start state. When the current loop is formed, the first-phase switching circuit 11 is in a soft-start state, which limits the current in the current loop, allowing the power conversion circuit 21 to also enter a soft-start state, reducing the impact of excessive charging current on the power conversion circuit 21 and the downstream load. Therefore, the above-mentioned configuration in this embodiment can reduce the number of switching circuits that need to be controlled by the external control signal, reduce the complexity of the circuit structure, and simplify the control logic.

[0021] Entering the soft-start state only requires controlling the conduction of one current loop, without the need to set up soft-start related components on each of the three-phase power supply lines. Therefore, this embodiment can also reduce the number of soft-start related components and reduce the complexity of the circuit structure.

[0022] Let's take a three-phase AC signal A coming from the power grid as an example. In one application scenario, refer to... Figure 1 The power conversion circuit 21 is a three-phase three-wire circuit, meaning that any two live wires can form a current loop with the power conversion circuit 21 that is connected to the power grid. Current flows between the power grid and the power conversion circuit 21 through these two live wires. In another application scenario, see [reference needed]. Figure 2 The power conversion circuit 21 is a three-phase four-wire circuit, meaning it is also connected to the neutral wire N. One live wire, one neutral wire N, and the power conversion circuit 21 form a current loop connected to the power grid. Current flows between the power grid and the power conversion circuit 21 through the live wire and the neutral wire N. When all three phases of the power supply lines are fully connected to the power conversion circuit 21, the power conversion circuit 21 enters the working state and can then output the working voltage to the load normally.

[0023] See Figure 1In a three-phase three-wire system, the three live wires can form three current loops with the power conversion circuit 21. The first phase power supply line U, the power conversion circuit 21, and the third phase power supply line W form one current loop; the first phase power supply line U, the power conversion circuit 21, and the second phase power supply line V form another; and the second phase power supply line V, the power conversion circuit 21, and the third phase power supply line W form yet another. Therefore, disconnecting two phases of the power supply line disconnects the connection between the power conversion circuit 21 and the power grid, preventing the formation of a complete current loop between the power conversion circuit 21 and the power grid, thus achieving zero active power during shutdown. Typically, one phase of the power supply line is kept fully conductive with the power conversion circuit 21.

[0024] For example, in some embodiments, the power conversion circuit 21 is a three-phase three-wire circuit, the power supply line W of the third phase is kept fully connected with the power conversion circuit 21, and the first phase switching circuit 11 receives an external control signal to make the power supply line U of the first phase, the power supply line W of the third phase, and the power conversion circuit 21 form a current loop.

[0025] Specifically, due to the functions of the first-phase switching circuit 11 and the second-phase switching circuit 12, in the off state, the power supply lines U and V of the first phase and the power conversion circuit 21 are all disconnected. When the first-phase switching circuit 11 receives an external control signal, it causes the power supply lines U and W of the first phase and the power conversion circuit 21 to form a current loop, and the power conversion circuit 21 enters a soft-start state.

[0026] See Figure 2 In a three-phase four-wire system, each of the three live wires can form a current loop with the neutral wire N and the power conversion circuit 21. The first phase's power supply line U, the power conversion circuit 21, and the neutral wire N form one current loop; the second phase's power supply line V, the power conversion circuit 21, and the neutral wire N form another current loop. Therefore, disconnecting the three-phase power supply lines disconnects the power conversion circuit 21 from the power grid, achieving zero active power during shutdown.

[0027] For example, in some embodiments, the power conversion circuit 21 is a three-phase four-wire circuit, and the power consumption control circuit further includes a third-phase switching circuit 13, which is connected in series on the power supply line W of the third phase; the first-phase switching circuit 11 is used to receive external control signals so that the power supply line U and the neutral line N of the first phase form the current loop with the power conversion circuit 21.

[0028] Specifically, the third-phase switching circuit 13 can control the on / off state of the power supply line and the power conversion circuit 21 of the corresponding phase. In the off state, the power supply lines of all three phases and the power conversion circuit 21 are disconnected. The first-phase switching circuit 11 receives an external control signal to make the power supply line U of the first phase, the neutral line N, and the power conversion circuit 21 form a current loop, and the power conversion circuit 21 enters the soft-start state.

[0029] In some embodiments, the power conversion circuit 21 is used to output a working electrical signal when the soft start is completed, and the first phase switching circuit 11 is also used to receive the working electrical signal to exit the soft start state and enter the full conduction state; at least the second phase switching circuit 12 is used to receive the working electrical signal to fully conduct the power supply line of the corresponding phase to the power conversion circuit 21, and all three phase power supply lines are fully connected to the power conversion circuit 21, so that the power conversion circuit 21 enters the working state.

[0030] After the soft start is completed, the impact of the current intensity in the fully conducting state on the power conversion circuit 21 and the subsequent load is reduced. Therefore, completing the soft start is a preparatory condition for the power conversion circuit 21 to enter the working state.

[0031] In a three-phase three-wire system scenario, refer to Figure 4 The third-phase power supply line W remains fully connected to the power conversion circuit 21. The operating electrical signal output by the power conversion circuit 21 controls the states of the first-phase switching circuit 11 and the second-phase switching circuit 12. Specifically, when the first-phase switching circuit 11 receives the operating electrical signal, it enters a fully connected state, controlling the first-phase power supply line U to be fully connected to the power conversion circuit 21. When the second-phase switching circuit 12 receives the operating electrical signal, it controls the second-phase power supply line V to be fully connected to the power conversion circuit 21. At this point, all three phase power supply lines are fully connected to the power conversion circuit 21, thus the power conversion circuit 21 enters its operating state.

[0032] It should be noted that the specific timing of the first-phase switching circuit 11 receiving the working electrical signal and the second-phase switching circuit 12 receiving the working electrical signal is not limited. For example, the two can switch states simultaneously, or the first-phase switching circuit 11 can receive the working electrical signal first and enter the fully conducting state, and then the second-phase switching circuit 12 can receive the working electrical signal to control the second-phase power supply line V and the power conversion circuit 21 to be fully conducting, etc.

[0033] In a three-phase four-wire system scenario, refer to Figure 6 The working electrical signal output by the power conversion circuit 21 can control the state of the first phase switching circuit 11, the second phase switching circuit 12, and the third phase switching circuit 13. For example, the power conversion circuit 21 is a three-phase four-wire circuit. The second phase switching circuit 12 and the third phase switching circuit 13 are used to receive the working electrical signal to connect the power supply line of the corresponding phase to the power conversion circuit 21, and the power conversion circuit 21 enters the working state.

[0034] Specifically, upon receiving the operating signal, the first-phase switching circuit 11 enters a fully conductive state, meaning it controls the first-phase power supply line U to be fully connected to the power conversion circuit 21. Upon receiving the operating signal, the second-phase switching circuit 12 controls the second-phase power supply line V to be fully connected to the power conversion circuit 21. Upon receiving the operating signal, the third-phase switching circuit 13 controls the third-phase power supply line W to be fully connected to the power conversion circuit 21. At this point, all three phase power supply lines are fully connected to the power conversion circuit 21, thus the power conversion circuit 21 enters its operating state.

[0035] It should be noted that the specific timing of the first-phase switching circuit 11 receiving the working electrical signal, the second-phase switching circuit 12 receiving the working electrical signal, and the third-phase switching circuit 13 receiving the working electrical signal is not limited. For example, the three can switch states simultaneously, or the first-phase switching circuit 11 can receive the working electrical signal first and enter a fully conducting state, and then the second-phase switching circuit 12 and the third-phase switching circuit 13 can receive the working electrical signal to control the power supply line and power conversion circuit 21 of the corresponding phase to be fully conducting, etc. No specific limitations are imposed.

[0036] In some embodiments, the power conversion circuit 21 is further configured to output a standby electrical signal when exiting the working state; the first phase switching circuit 11 is further configured to receive the standby electrical signal to exit the fully conducting state and enter the soft-start state; at least the second phase switching circuit 12 is further configured to receive the standby electrical signal to disconnect the power supply line of the corresponding phase from the power conversion circuit 21, and the power conversion circuit 21 enters the soft-start state.

[0037] In a three-phase three-wire system scenario, refer to Figure 4 or Figure 5 The power supply line W of the third phase remains fully connected to the power conversion circuit 21. The standby signal output by the power conversion circuit 21 controls the state of the first-phase switching circuit 11 and the second-phase switching circuit 12. Specifically, when the first-phase switching circuit 11 receives the standby signal, it returns to the soft-start state, that is, it controls the power supply line U of the first phase to be partially connected to the power conversion circuit 21. When the second-phase switching circuit 12 receives the standby signal, it controls the power supply line V of the second phase to be disconnected from the power conversion circuit 21. At this point, there is only one current loop between the three-phase power supply lines and the power conversion circuit 21, that is, the current loop formed by the power supply line U of the first phase, the power conversion circuit 21, and the power supply line W of the third phase. Therefore, the power conversion circuit 21 exits the working state and returns to the soft-start state. The power conversion circuit 21 is in standby mode in this state, which facilitates its re-entry into the working state in the corresponding application scenario. In this state, the external control signal can disconnect the current loop between the power supply line U of the first phase and the power conversion circuit 21 simply by controlling the first phase switching circuit 11, so that the power conversion circuit 21 enters the shutdown state and achieves zero active power.

[0038] It should be noted that the specific timing of the first-phase switching circuit 11 receiving the standby electrical signal and the second-phase switching circuit 12 receiving the standby electrical signal is not limited. For example, the two can switch states simultaneously, or the first-phase switching circuit 11 can receive the standby electrical signal first to enter the soft-start state, and then the second-phase switching circuit 12 can receive the standby electrical signal to control the power supply line V of the second phase to disconnect from the power conversion circuit 21, etc.

[0039] In a three-phase four-wire system scenario, refer to Figure 6 The standby signal output by the power conversion circuit 21 can control the states of the first-phase switching circuit 11, the second-phase switching circuit 12, and the third-phase switching circuit 13. Specifically, when the first-phase switching circuit 11 receives the standby signal, it enters a soft-start state, that is, it controls the power supply line U of the first phase to exit the fully conductive state of the power conversion circuit 21. When the second-phase switching circuit 12 receives the standby signal, it controls the power supply line V of the second phase to disconnect from the power conversion circuit 21. When the third-phase switching circuit 13 receives the standby signal, it controls the power supply line W of the third phase to disconnect from the power conversion circuit 21. At this point, there is only one current loop between the three-phase power supply lines and the power conversion circuit 21, namely the current loop formed by the power supply line U of the first phase, the power conversion circuit 21, and the neutral line N. Therefore, the power conversion circuit 21 exits the working state and returns to the soft-start state. The power conversion circuit 21 is in standby mode in this state, which facilitates its re-entry into the working state in the corresponding application scenario. In this state, the external control signal can disconnect the current loop between the power supply line U of the first phase and the power conversion circuit 21 simply by controlling the first phase switching circuit 11, so that the power conversion circuit 21 enters the shutdown state and achieves zero active power.

[0040] It should be noted that the specific timing of the first-phase switching circuit 11 receiving the standby signal, the second-phase switching circuit 12 receiving the standby signal, and the third-phase switching circuit 13 receiving the standby signal is not limited. For example, the three can switch states simultaneously, or the first-phase switching circuit 11 can receive the standby signal first and enter a soft-start state, and then the second-phase switching circuit 12 and the third-phase switching circuit 13 can receive the standby signal to control the power supply line of the corresponding phase to disconnect from the power conversion circuit 21, etc. No specific limitations are imposed.

[0041] See Figure 3 , Figure 4In some embodiments, the first phase switching circuit 11 includes a first phase switching unit 111 and a soft-start circuit 112. The first phase switching unit 111 is used to receive an external control signal to make the power supply line U of the first phase form a current loop with the power conversion circuit 21. The soft-start circuit 112 has an adjustable resistance value and is connected in series between the first phase switching unit 111 and the power conversion circuit 21. It is used to receive a working electrical signal to control the adjustable resistance value to return to zero, so that the first phase switching circuit 11 exits the soft-start state and enters the fully conducting state.

[0042] In an application scenario, such as Figure 4 As shown, the first phase switching unit 111 includes a first relay CH1, and the second phase switching circuit 12 includes a second relay CH2. The soft-start circuit 112 has an adjustable resistance value. When a current loop is formed, the soft-start circuit 112 is connected in series in the current loop, enabling the first phase switching circuit 11 to enter a soft-start state, thus preventing the first phase power supply line U from being fully connected to the power conversion circuit 21. When the soft-start is complete, the soft-start circuit 112 receives a working electrical signal, controlling the adjustable resistance value to return to zero, allowing the current loop to achieve full conduction.

[0043] In some embodiments, the soft-start circuit 112 can also be used to receive the aforementioned standby electrical signal to control the adjustable resistance value to be non-zero. For example, it can be set to a preset soft-start resistance value so that the power supply line U of the first phase and the power conversion circuit 21 return to a state of incomplete conduction, that is, the first phase switching circuit 11 enters the soft-start state.

[0044] See Figures 3 to 4 In some embodiments, the soft start circuit 112 includes a soft start resistor R and a short-circuit switch 113 connected in parallel. The short-circuit switch 113 is used to receive a working electrical signal to short-circuit the soft start resistor R.

[0045] In an application scenario, such as Figure 4 As shown, the first phase switch unit 111 includes a first relay CH1, and the short-circuit switch 113 includes a fourth relay CH4.

[0046] Specifically, when the soft start is completed, the short-circuit switch 113 receives the working electrical signal and closes to short-circuit the soft start resistor R, so that the resistance value of the power supply line U connected to the first phase is reduced to zero, thereby enabling the power supply line U of the first phase and the power conversion circuit 21 to achieve full conduction.

[0047] In some embodiments, the short-circuit switch 113 can also be used to receive the aforementioned standby electrical signal to disconnect the short-circuit loop, so that the soft-start resistor R is reconnected to the current loop formed by the power supply line U of the first phase and the power conversion circuit 21.

[0048] In other embodiments, the soft-start circuit 112 may also use a component with adaptive current limiting characteristics, such as a positive temperature coefficient thermistor, or may achieve dynamic current limiting through an electronic switching circuit (such as a silicon controlled rectifier or a MOSFET), without any specific limitation.

[0049] In some embodiments, see Figure 5 The first phase switching circuit 11 includes a first phase switching unit 111, a soft-start resistor R, and a short-circuit switch 113. The first phase switching unit 111 is used to receive external control signals to control the on / off state of the first phase power supply line U; the soft-start resistor R is connected in series between the first phase switching unit 111 and the power conversion circuit 21; the short-circuit switch 113 is connected in parallel with the first phase switching unit 111 and the soft-start resistor R, and the short-circuit switch 113 is used to receive working electrical signals to short-circuit the first phase switching unit 111 and the soft-start resistor R.

[0050] In an application scenario, such as Figure 5 As shown, the first phase switch unit 111 includes a first relay CH1, the second phase switch circuit 12 includes a second relay CH2, and the short-circuit switch 113 includes a fourth relay CH4.

[0051] In some embodiments, the short-circuit switch 113 can also be used to receive the aforementioned standby electrical signal to disconnect the short-circuit loop, so that the first phase switch unit 111 and the soft-start resistor R are reconnected to the current loop formed by the power supply line U of the first phase and the power conversion circuit 21.

[0052] In some embodiments, see Figures 4 to 5 The power consumption control circuit also includes a first line capacitor C1, a second line capacitor C2, and a third line capacitor C3. One end of the first line capacitor C1 is connected to the output terminal of the soft-start resistor R, and the other end is connected to the output terminal of the second-phase switching circuit 12. One end of the second line capacitor C2 is connected to the output terminal of the soft-start resistor R, and the other end is connected to the power supply line W of the third phase. One end of the third line capacitor C3 is connected to the output terminal of the second-phase switching circuit 12, and the other end is connected to the power supply line W of the third phase.

[0053] In this way, when the power consumption control circuit controls the power conversion circuit 21 to return from the working state to the soft-start state under the action of the standby electrical signal, the external control signal can achieve zero reactive power and zero active power simply by controlling the first phase switching circuit 11. The following example illustrates this, where the first phase switching unit 111 includes a first relay CH1, the second phase switching circuit 12 includes a second relay CH2, the third phase switching circuit 13 includes a third relay CH3, and the short-circuit switch 113 includes a fourth relay CH4.

[0054] In a three-phase three-wire system scenario, refer to Figure 4 , Figure 5When the power conversion circuit 21 returns from the working state to the soft-start state, the second-phase switching circuit 12 receives a standby signal and controls the second-phase power supply line V to disconnect from the power conversion circuit 21. Therefore, the first-phase capacitor C1 and the third-phase capacitor C3 both exit the power consumption state. A current loop exists between the three-phase power supply lines and the power conversion circuit 21, forming a current loop consisting of the first-phase power supply line U, the power conversion circuit 21, and the third-phase power supply line W. Therefore, the second-phase capacitor C2 is in the power consumption state. Thus, an external control signal can disconnect this current loop simply by controlling the first-phase switching circuit 11, causing the power conversion circuit 21 to enter the shutdown state and the second-phase capacitor C2 to exit the power consumption state. There is no active power consumption in the power conversion circuit 21, and no reactive power consumption in the power consumption control circuit, achieving zero reactive and zero active power consumption.

[0055] In a three-phase four-wire system scenario, refer to Figure 6 , Figure 7 When the power conversion circuit 21 returns from the working state to the soft-start state, the second-phase switching circuit 12 receives the standby electrical signal and controls the power supply line V of the second phase to disconnect from the power conversion circuit 21. Therefore, the first-line capacitor C1 and the third-line capacitor C3 both exit the power consumption state. The third-phase switching circuit 13 receives the standby electrical signal and controls the power supply line W of the third phase to disconnect from the power conversion circuit 21. Therefore, the second-line capacitor C2 exits the power consumption state. Thus, there is no reactive power consumption in the power consumption control circuit. There is only a current loop formed by the first-phase power supply line U, the power conversion circuit 21, and the neutral line N between the three-phase power supply lines and the power conversion circuit 21. Therefore, the external control signal can disconnect this current loop simply by controlling the first-phase switching circuit 11, so that the power conversion circuit 21 enters the shutdown state. There is no active power consumption in the power conversion circuit 21, thus achieving zero reactive power and zero active power consumption.

[0056] In some embodiments, based on usage requirements, the improved circuit design of the above embodiments can also achieve low reactive power and zero active power by controlling the first phase switching circuit 11 alone through external control signals. Specifically, one end of the first line capacitor C1 is connected to the output terminal of the first phase switching circuit 11, and the other end is connected to the input terminal of the second phase switching circuit 12; one end of the second line capacitor C2 is connected to the output terminal of the first phase switching circuit 11, and the other end is connected to the power supply line W of the third phase; one end of the third line capacitor C3 is connected to the input terminal of the second phase switching circuit 12, and the other end is connected to the power supply line W of the third phase.

[0057] See below Figure 8 , Figure 9 To illustrate, the example is that the first phase switch unit 111 includes a first relay CH1, the second phase switch circuit 12 includes a second relay CH2, the third phase switch circuit 13 includes a third relay CH3, and the short-circuit switch 113 includes a fourth relay CH4.

[0058] In a three-phase three-wire system scenario, refer to Figure 8 When the power conversion circuit 21 returns from the working state to the soft-start state, the second-phase switching circuit 12 receives a standby signal and controls the second-phase power supply line V to disconnect from the power conversion circuit 21. However, the first-line capacitor C1 and the third-line capacitor C3 are connected to the input terminal of the second-phase switching circuit 12, so the first-line capacitor C1 and the third-line capacitor C3 are still in the power consumption state. There is also a current loop formed by the first-phase power supply line U, the power conversion circuit 21, and the third-phase power supply line W between the three-phase power supply lines and the power conversion circuit 21, so the second-line capacitor C2 is in the power consumption state. When the first-phase switching circuit 11 disconnects this current loop, the power conversion circuit 21 enters the shutdown state, achieving zero active power. At this time, the first-line capacitor C1 and the second-line capacitor C2 exit the power consumption state. However, since the third-line capacitor C3 is connected between the input terminal of the second-phase switching circuit 12 and the third-phase power supply line W, the second-phase switching circuit 12 cannot disconnect the current loop between the second-phase power supply line V, the third-line capacitor C3, and the third-phase power supply line W. Therefore, the AC power input from the grid can still generate reactive power consumption within the third-line capacitor C3, meaning there is low reactive power consumption in the power control circuit. In summary, the external control signal can achieve low reactive power and zero active power consumption in the power control circuit when it is off simply by controlling the first-phase switching circuit 11.

[0059] In a three-phase four-wire system scenario, refer to Figure 9 When the power conversion circuit 21 returns from the working state to the soft-start state, the second-phase switching circuit 12 receives the standby power signal and controls the power supply line V of the second phase to disconnect from the power conversion circuit 21. Similarly, the third-phase switching circuit 13 receives the standby power signal and controls the power supply line W of the third phase to disconnect from the power conversion circuit 21. However, the first-line capacitor C1 and the third-line capacitor C3 are connected to the input terminal of the second-phase switching circuit 12, so at least the first-line capacitor C1 remains in a power-consuming state. If both the second-line capacitor C2 and the third-line capacitor C3 are connected to the input terminal of the third-phase switching circuit 13, then both will also remain in a power-consuming state. An external control signal can be used to control the first-phase switching circuit 11 to eliminate active power consumption in the power conversion circuit 21 and cause the first-line capacitor C1 and the second-line capacitor C2 to exit the power-consuming state. When the third line capacitor C3 is connected to the input terminal of the third phase switching circuit 13, there is still a current loop formed by the power supply line V of the second phase, the third line capacitor C3, and the power supply line W of the third phase in the power consumption control circuit. That is, the third line capacitor C3 has reactive power consumption. In this circuit structure, the external control signal can achieve low reactive power and zero active power by controlling the first phase switching circuit 11.

[0060] In other embodiments, the first line capacitor C1, the second line capacitor C2, and the third line capacitor C3 can also be connected in a star configuration: one end of the three capacitors is connected to the power supply lines W of the first phase, the second phase, and the third phase, respectively, and the other end is connected to the same neutral point; this neutral point is left floating in a three-phase three-wire system and can be connected to the neutral line N in a three-phase four-wire system, and the specific design can be determined according to the application scenario.

[0061] In some embodiments, at least one of the first phase switching circuit 11, the second phase switching circuit 12, and the third phase switching circuit 13 includes a magnetic latching relay, a conventional relay, or an electronic switching device.

[0062] Specifically, at least one of the first phase switching unit 111 and the short-circuit switch 113 can be a magnetic latching relay, a conventional relay, or an electronic switching device. Magnetic latching relays have the characteristic of zero-power holding state, which can significantly reduce standby power consumption; conventional relays are low-cost and have stable switching capabilities; electronic switching devices have fast response speeds, meeting the requirements of high-frequency soft-start or precision control. Magnetic latching relays and conventional relays have strong surge current tolerance, and electronic switching devices have no mechanical wear, making them suitable for high-frequency switching scenarios.

[0063] This application further proposes a three-phase power supply, such as Figures 1 to 9 As shown, it includes the power consumption control circuit and power conversion circuit 21 described in any of the above embodiments, and the power conversion circuit 21 is connected to the power consumption control circuit.

[0064] Specifically, the output terminal of the power conversion circuit 21 is connected to the load and is used to output a working electrical signal when the soft start is completed; the power consumption control circuit includes three-phase power supply lines, a first-phase switching circuit 11, and a second-phase switching circuit 12. The input terminals of the three-phase power supply lines are respectively connected to three-phase AC signals A, and the output terminals are respectively connected to the power conversion circuit 21; the first-phase switching circuit 11 is connected in series on the first-phase power supply line U; the second-phase switching circuit 12 is connected in series on the second-phase power supply line V; wherein, the first-phase switching circuit 11 is used to receive an external control signal to make the first-phase power supply line U and the power conversion circuit 21 form a current loop. When the current loop is formed, the first-phase switching circuit 11 and the power conversion circuit 21 enter the soft start state; the first-phase switching circuit 11 is also used to receive a working electrical signal to exit the soft start state and enter the full conduction state; at least the second-phase switching circuit 12 is used to receive a working electrical signal to fully conduct the power supply line of the corresponding phase and the power conversion circuit 21. All three-phase power supply lines are fully connected to the power conversion circuit 21, and the power conversion circuit 21 enters the working state.

[0065] The specific implementation method and working principle of the power consumption control circuit can be referred to the above embodiments, and will not be repeated here.

[0066] Unlike existing technologies, the three-phase power supply of this application includes a power conversion circuit and a power consumption control circuit connected thereto. The output terminal of the power conversion circuit is connected to the load and is used to output a working electrical signal when the soft start is completed. The power consumption control circuit includes three-phase power supply lines, a first-phase switching circuit, and a second-phase switching circuit. The input terminals of the three-phase power supply lines are respectively connected to three-phase AC electrical signals, and the output terminals are respectively connected to the power conversion circuit. The first-phase switching circuit is connected in series on the first-phase power supply line; the second-phase switching circuit is connected in series on the second-phase power supply line. The first-phase switching circuit receives an external control signal to form a current loop between the first-phase power supply line and the power conversion circuit. When a current loop is formed, the first-phase switching circuit and the power conversion circuit enter a soft-start state. The first-phase switching circuit also receives a working electrical signal to exit the soft-start state and enter a fully conductive state. At least the second-phase switching circuit receives a working electrical signal to fully conduct the corresponding phase power supply line and the power conversion circuit. All three phase power supply lines are fully conductive with the power conversion circuit, and the power conversion circuit enters the working state. In this application, the external control signal only controls the first-phase switching circuit to enable the power conversion circuit to enter the soft-start state. Specifically, in a three-phase four-wire system, there exists a neutral line that remains fully conductive with the power conversion circuit for an extended period; or in a three-phase three-wire system, there exists another power supply line that remains fully conductive with the power conversion circuit for an extended period. The first-phase switching circuit, upon receiving an external control signal, enables the first-phase power supply line to connect with the power conversion circuit and form a current loop. This prepares the circuit for the power conversion circuit to enter a soft-start state. When the current loop is formed, the first-phase switching circuit is in a soft-start state, which limits the current within the loop, allowing the power conversion circuit to also enter a soft-start state. This reduces the impact of excessive charging current on the power conversion circuit and subsequent loads. Therefore, the above-mentioned configuration in this application reduces the number of switching circuits that need to be controlled by external control signals, lowers the complexity of the circuit structure, and simplifies the control logic.

[0067] It is worth noting that the accompanying drawings are only for illustrating the structural and connection relationships of the product in this application, and do not limit the specific structural dimensions of the product in this application.

[0068] The above description is merely an embodiment of this application and does not limit the patent scope of this application. Any equivalent structural or procedural transformations made using the content of this application's specification and drawings, or direct or indirect applications in other related technical fields, are similarly included within the patent protection scope of this application.

Claims

1. A power consumption control circuit for a three-phase power supply, characterized in that, The three-phase power supply includes a power conversion circuit and a power consumption control circuit connected to the power conversion circuit. The output terminal of the power conversion circuit is connected to the load and is used to output a working electrical signal when the soft start is completed. The power consumption control circuit includes: The three-phase power supply line has three-phase AC signals connected to its input terminals and its output terminals connected to the power conversion circuit. The first phase switching circuit is connected in series with the power supply line of the first phase; The second phase switching circuit is connected in series with the power supply line of the second phase; The first phase switching circuit is used to receive external control signals so that the power supply line of the first phase and the power conversion circuit form a current loop. When the current loop is formed, the first phase switching circuit and the power conversion circuit enter a soft start state. The first phase switching circuit is also used to receive the working electrical signal to exit the soft-start state and enter the full conduction state; at least the second phase switching circuit is used to receive the working electrical signal to fully conduct the power supply line of the corresponding phase and the power conversion circuit, and all three phase power supply lines are fully connected to the power conversion circuit, and the power conversion circuit enters the working state.

2. The power consumption control circuit according to claim 1, characterized in that, The power conversion circuit is a three-phase three-wire circuit. The power supply line of the third phase is fully connected to the power conversion circuit. The first phase switching circuit is used to receive the external control signal so that the power supply line of the first phase, the power supply line of the third phase, and the power conversion circuit form the current loop.

3. The power consumption control circuit according to claim 1, characterized in that, The first phase switching circuit includes: The first phase switching unit is used to receive the external control signal so that the power supply line of the first phase and the power conversion circuit form a current loop; The soft-start circuit has an adjustable resistance value and is connected in series between the first phase switch unit and the power conversion circuit. It is used to receive the working electrical signal to control the adjustable resistance value to return to zero, so that the first phase switch circuit exits the soft-start state and enters the full conduction state.

4. The power consumption control circuit according to claim 3, characterized in that, The soft-start circuit includes: A soft-start resistor and a short-circuit switch are connected in parallel. The short-circuit switch is used to receive the working electrical signal to short-circuit the soft-start resistor.

5. The power consumption control circuit according to claim 1, characterized in that, The first phase switching circuit includes: The first phase switching unit is used to receive the external control signal to control the on / off state of the power supply line of the first phase; A soft-start resistor is connected in series between the first phase switching unit and the power conversion circuit; A short-circuit switch is connected in parallel with the first phase switch unit and the soft-start resistor. The short-circuit switch is used to receive the working electrical signal to short-circuit the first phase switch unit and the soft-start resistor.

6. The power consumption control circuit according to any one of claims 4 or 5, characterized in that, The power consumption control circuit further includes: The first line capacitor has one end connected to the output terminal of the soft-start resistor and the other end connected to the output terminal of the second phase switching circuit. The second capacitor has one end connected to the output terminal of the soft-start resistor and the other end connected to the power supply line of the third phase. The third-line capacitor has one end connected to the output terminal of the second-phase switching circuit and the other end connected to the power supply line of the third phase.

7. The power consumption control circuit according to claim 3, characterized in that, The power consumption control circuit further includes: The first line capacitor has one end connected to the output terminal of the first phase switching circuit and the other end connected to the input terminal of the second phase switching circuit. The second-line capacitor has one end connected to the output terminal of the first-phase switching circuit and the other end connected to the power supply line of the third phase. The third-line capacitor has one end connected to the input terminal of the second-phase switching circuit and the other end connected to the power supply line of the third phase.

8. The power consumption control circuit according to claim 1, characterized in that, The power conversion circuit is a three-phase four-wire circuit, and the power consumption control circuit further includes a third-phase switching circuit, which is connected in series with the third-phase power supply line. The first phase switching circuit is used to receive external control signals so that the power supply line and neutral line of the first phase and the power conversion circuit form the current loop; The second phase switching circuit and the third phase switching circuit are used to receive the working electrical signal to connect the power supply line of the corresponding phase to the power conversion circuit, and the power conversion circuit enters the working state.

9. The power consumption control circuit according to claim 8, characterized in that, At least one of the first phase switching circuit, the second phase switching circuit, and the third phase switching circuit includes a magnetic latching relay, a general relay, or an electronic switching device.

10. A three-phase power supply, characterized in that, It includes a power conversion circuit and a power consumption control circuit as described in any one of claims 1 to 9, wherein the power conversion circuit is connected to the power consumption control circuit.

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