A zero-power control circuit, a charging pile and a zero-power control method

Abstract

The application provides a zero-power consumption control circuit, a charging pile and a zero-power consumption control method. The circuit comprises a zero-reactive power control module, a zero-power consumption control module, an auxiliary power supply and a post-stage circuit. The zero-reactive power control module is configured to control the state of an internal switch node thereof based on the working state of the post-stage circuit. The zero-power consumption control module is configured to acquire the working state of the post-stage circuit and control the auxiliary power supply to be turned off when the working state of the post-stage circuit meets a target working state. When the post-stage circuit is in a zero-reactive power mode, if a zero-power consumption control signal is received, the auxiliary power supply is controlled to be turned off, so that the post-stage circuit enters a zero-power consumption mode. Through the implementation of the application, when the main power path of the charging module is disconnected, i.e., in the zero-reactive power mode, the auxiliary power supply is further controlled to stop working by the zero-power consumption control module, so as to reduce the reactive power consumption of the alternating current power grid.

Description

Technical Field

[0001] This application belongs to the field of power electronics, and in particular relates to a zero-power control circuit, a charging pile, and a zero-power control method. Background Technology

[0002] As the core component of a charging pile, the charging pile module plays a crucial role in converting the AC power input from the grid into the DC power required by the electric vehicle battery. In recent years, with the continuous increase in charging pile power, the number of parallel modules required has also increased, making the reactive power generated by multiple parallel modules during standby increasingly prominent. Standby reactive power is mainly generated by downstream circuits, with capacitors playing a dominant role. Therefore, optimizing standby reactive power requires addressing the impact of capacitors in downstream circuits.

[0003] The solution in related technologies is to add a relay on the input side of the module. When the module is in standby mode, the reactive power components inside the charging module are disconnected from the AC power grid, allowing the module to enter a zero reactive power mode. However, in this operating mode, the module's auxiliary power supply is still working. Since the auxiliary power supply does not have a power factor correction function, it will still consume a small amount of active power (reactive power from the AC power grid). Therefore, this operating mode can only solve most of the reactive power consumption, while the reactive power consumption caused by the auxiliary power supply remains unresolved. Summary of the Invention

[0004] This application provides a zero-power control circuit, a charging pile, and a zero-power control method, aiming to solve the problem in related technologies that the auxiliary power supply still generates a lot of reactive power when the main power path of the charging module is disconnected.

[0005] To address the aforementioned technical problems, the first aspect of this application provides a zero-power control circuit, including a zero-reactive-load control module, an auxiliary power supply, and a subsequent circuit. The AC input terminal of the zero-reactive-load control module is electrically connected to the AC power grid, the power output terminal of the zero-reactive-load control module is electrically connected to the subsequent circuit, the status output terminal of the zero-reactive-load control module is electrically connected to the status input terminal of the zero-power-load control module, the power input terminal of the auxiliary power supply is electrically connected to the DC bus of the subsequent circuit, the control terminal of the auxiliary power supply is electrically connected to the control output terminal of the zero-power-load control module, and the signal input terminal of the zero-power-load control module is electrically connected to the DC side of the subsequent circuit. The zero reactive power control module is configured to control the state of its internal switching nodes based on the operating state of the downstream circuit; wherein, when the downstream circuit enters the operating mode, it controls its internal switching nodes to be in a first state, so that a main power path is formed between the downstream circuit and the AC power grid; when the downstream circuit is in standby mode, it controls its internal switching nodes to be in a second state, so that the main power path formed between the downstream circuit and the AC power grid is disconnected and enters the zero reactive power mode; The zero-power control module is configured to acquire the operating state of the downstream circuit, and control the auxiliary power supply to turn off when the operating state of the downstream circuit meets the target operating state; wherein, when the downstream circuit is in zero reactive power mode, if a zero-power control signal is received, the auxiliary power supply is controlled to turn off so that the downstream circuit enters zero-power mode.

[0006] In one embodiment, the system further includes an uncontrolled rectifier unit; the power output terminal of the zero-reactive-state control module includes a first power output terminal and a second power output terminal, the first power output terminal of the zero-reactive-state control module is electrically connected to the subsequent circuit, the second power output terminal of the zero-reactive-state control module is electrically connected to the input terminal of the uncontrolled rectifier unit, and the output terminal of the uncontrolled rectifier unit is electrically connected to the DC bus of the subsequent circuit; wherein, when the internal switching node of the zero-reactive-state control module is in a first state, an open circuit is formed between the uncontrolled rectifier unit and the AC power grid; when the internal switching node of the zero-reactive-state control module is in a second state, a closed circuit is formed between the uncontrolled rectifier unit and the AC power grid.

[0007] In one embodiment, the zero reactive power control module includes a main zero reactive power control unit and an auxiliary zero reactive power control unit. The first terminal of the main zero reactive power control unit and the first terminal of the auxiliary zero reactive power control unit together constitute the AC input terminal of the zero reactive power control module. The second terminal of the main zero reactive power control unit and the second terminal of the auxiliary zero reactive power control unit are connected in parallel to form the first power output terminal of the zero reactive power control module. The third terminal of the auxiliary zero reactive power control unit forms the second power output terminal of the zero reactive power control module. Specifically, when the internal switch node of the zero reactive power control module is in the first state, the internal switch node of the main zero reactive power control unit is closed, and the normally open contact of the internal switch of the auxiliary zero reactive power control module is closed; when the internal switch node of the zero reactive power control module is in the second state, the internal switch node of the main zero reactive power control unit is open, and the normally closed contact of the internal switch of the auxiliary zero reactive power control module is closed.

[0008] In one embodiment, the AC input terminal of the zero reactive power control module includes a first phase input terminal, a second phase input terminal, and a third phase input terminal; the first power output terminal of the zero reactive power control module includes a first phase output terminal, a second phase output terminal, and a third phase output terminal; the main zero reactive power control unit includes a first main relay, a second main relay, a third main relay, and a fourth main relay; and the auxiliary zero reactive power control unit includes a first auxiliary relay, a second auxiliary relay, a first resistor, and a second resistor. The first terminal of the first main relay, the first terminal of the second main relay, and the normally open contact of the first auxiliary relay are connected in parallel and electrically connected to the first phase input terminal. The second terminal of the first main relay, the second terminal of the second main relay, and the second terminal of the first resistor are connected in parallel and electrically connected to the first phase output terminal. The second terminal of the first auxiliary relay is electrically connected to the first terminal of the first resistor. The first terminal of the third main relay, the first terminal of the fourth main relay, and the normally open contact of the second auxiliary relay are connected in parallel and electrically connected to the second phase input terminal. The second terminal of the third main relay, the second terminal of the fourth main relay, and the second terminal of the second resistor are connected in parallel and electrically connected to the second phase output terminal. The second terminal of the second auxiliary relay is electrically connected to the first terminal of the second resistor. The normally closed contact of the second auxiliary relay is electrically connected to the second power output terminal.

[0009] In one embodiment, the uncontrolled rectifier unit includes a third resistor, a first diode, and a second diode. The first end of the third resistor is electrically connected to the second power output terminal, and the second end of the third resistor is electrically connected to the cathode of the first diode and the anode of the second diode, respectively. The anode of the first diode is electrically connected to the positive terminal of the DC bus, and the cathode of the second diode is electrically connected to the negative terminal of the DC bus.

[0010] In one embodiment, the zero-power control module includes an isolation unit, a switch execution unit, and an enable unit; The primary side of the isolation unit serves as the signal input terminal of the zero-power control module and is electrically connected to the DC side of the subsequent circuit. The isolation unit is configured to receive the zero-power control signal and electrically isolate the signal. The control terminal of the switch execution unit is electrically connected to the secondary side of the isolation unit. The output terminal of the switch execution unit serves as the control output terminal of the zero-power control module and is electrically connected to the control terminal of the auxiliary power supply. The switch execution unit is configured to turn off the auxiliary power supply when it is turned on. The enabling unit is connected in series between the secondary side of the isolation unit and the control terminal of the switching execution unit. The trigger terminal of the enabling unit serves as the state input terminal of the zero-power control module and is electrically connected to the state output terminal of the zero-reactive power control module. The enabling unit is configured to control the conduction permission of the switching execution unit according to the working state of the subsequent circuit.

[0011] In one embodiment, the isolation unit includes a PWM controller, an isolation capacitor, and an isolation transformer. The power supply terminal of the PWM controller is electrically connected to the DC side of the subsequent circuit. The signal output terminal of the PWM controller is connected in series with the isolation capacitor and then electrically connected to the primary winding of the isolation transformer. The secondary winding of the isolation transformer is electrically connected to the switching execution unit.

[0012] In one embodiment, the switching execution unit includes a first optocoupler, a second optocoupler, and a composite transistor module; The light-emitting diode on the primary side of the first optocoupler is connected in series with the secondary winding circuit of the isolation transformer. The collector of the phototransistor on the secondary side of the first optocoupler is electrically connected to the auxiliary power supply. The emitter of the phototransistor on the secondary side of the first optocoupler is electrically connected to the first terminal of the enabling unit and the composite transistor module, respectively. The anode of the primary-side light-emitting diode of the second optocoupler is electrically connected to the auxiliary power supply, the cathode of the primary-side light-emitting diode of the second optocoupler is electrically connected to the second terminal of the composite transistor module, the collector of the secondary-side phototransistor of the second optocoupler is electrically connected to the enable terminal of the auxiliary power supply, and the emitter of the secondary-side phototransistor of the second optocoupler is electrically connected to the reference ground of the auxiliary power supply. The third terminal of the composite transistor module is grounded together with the output terminal of the enable unit.

[0013] A second aspect of this application provides a charging pile, the charging pile including a zero-power control circuit as described in any of the preceding claims.

[0014] A third aspect of this application provides a zero-power control method applied to a zero-power control circuit. The zero-power control circuit includes a zero-reactive-state control module, an auxiliary power supply, and a subsequent circuit. The AC input terminal of the zero-reactive-state control module is electrically connected to the AC power grid, the power output terminal of the zero-reactive-state control module is electrically connected to the subsequent circuit, the status output terminal of the zero-reactive-state control module is electrically connected to the status input terminal of the zero-power control module, the power input terminal of the auxiliary power supply is electrically connected to the DC bus of the subsequent circuit, the control terminal of the auxiliary power supply is electrically connected to the control output terminal of the zero-power control module, and the signal input terminal of the zero-power control module is electrically connected to the DC side of the subsequent circuit. The zero reactive power control module controls the state of its internal switching nodes based on the operating state of the downstream circuit. Specifically, when the downstream circuit enters the operating mode, it controls its internal switching nodes to be in a first state to form a main power path between the downstream circuit and the AC power grid. When the downstream circuit is in standby mode, it controls its internal switching nodes to be in a second state to form a circuit break between the downstream circuit and the AC power grid and enter the zero reactive power mode. The zero-power control module acquires the operating state of the downstream circuit. When the operating state of the downstream circuit meets the target operating state, it controls the auxiliary power supply to be turned off. Specifically, when the downstream circuit is in zero-reactive-mode, if a zero-power control signal is received, the auxiliary power supply is controlled to be turned off so that the downstream circuit enters zero-power mode.

[0015] The zero-power control circuit provided in this application embodiment controls the connection between the downstream circuit and the AC power grid through a zero-reactive-power control module. This allows the downstream circuit to disconnect from the AC terminal during standby, disconnecting the capacitors in the downstream circuit. The zero-power control module then further shuts off the auxiliary power supply, enabling the downstream circuit to switch to zero-power mode while already in zero-reactive-power mode, eliminating reactive power consumption from the auxiliary power supply. Through the implementation of this application, on the one hand, when the main power path of the charging module is disconnected, i.e., in zero-reactive-power mode, the zero-power control module further stops the auxiliary power supply, reducing the active power consumption of the auxiliary power supply (reactive power consumption of the AC power grid), further reducing losses to power supply equipment and lines, and minimizing the impact on grid voltage fluctuations, thus improving power quality and achieving energy savings. On the other hand, this application also addresses the pain points caused by the use of AC relays in charging piles in related solutions, further reducing the reactive power consumption of the module and improving the reliability of the charging pile. Attached Figure Description

[0016] To more clearly illustrate the related technologies or the technical solutions in the embodiments of this application, the drawings used in the description of the related technologies or the embodiments of this application will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application, and not all embodiments. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0017] Figure 1 This is a schematic diagram of a zero-power control circuit provided in the first aspect of the embodiments of this application; Figure 2 A partial structural schematic diagram of a refined zero-power control circuit provided for the first aspect of the embodiments of this application; Figure 3 A partial structural schematic diagram of another refined zero-power control circuit provided for the first aspect of the embodiments of this application; Figure 4 A partial structural schematic diagram of another refined zero-power control circuit provided in the first aspect of the embodiments of this application; Figure 5 A detailed overall structural schematic diagram of a zero-power control circuit provided for the first aspect of the embodiments of this application; Figure 6 This is a schematic diagram of the structure of a zero-power control module provided in the first aspect of the embodiments of this application; Figure 7 A logic control diagram for a zero-power mode provided in the first aspect of the embodiments of this application; Figure 8 This is a schematic diagram of a charging pile provided in the second aspect of the embodiments of this application. Detailed Implementation

[0018] To make the technical problems, technical solutions, and beneficial effects to be solved by this application clearer, the following detailed description is provided in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and are not intended to limit the scope of this application.

[0019] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this application, "multiple" means one or more, unless otherwise explicitly specified.

[0020] As the core component of a charging pile, the charging pile module plays a crucial role in converting the AC power input from the grid into the DC power required by the electric vehicle battery. In recent years, with the continuous increase in charging pile power, the number of parallel modules required has also increased, making the reactive power generated by multiple parallel modules during standby increasingly prominent. Standby reactive power is mainly generated by downstream circuits, with capacitors playing a dominant role. Therefore, optimizing standby reactive power requires addressing the impact of capacitors in downstream circuits.

[0021] The existing solution involves adding a relay to the input side of the module. When the module is in standby mode, this disconnects the internal reactive power components from the AC grid, putting the module into a zero-reactive-power mode. However, in this mode, the auxiliary power supply continues to operate. Since the auxiliary power supply lacks power factor correction, it still incurs a small amount of active power consumption (reactive power consumption from the AC grid). Therefore, this solution only addresses most of the reactive power consumption, leaving the reactive power consumption from the auxiliary power supply unresolved. Thus, there is an urgent need for a control circuit that can further reduce reactive power consumption.

[0022] Figure 1 A schematic diagram of a zero-power control circuit according to the first aspect of an embodiment of this application is shown. For ease of explanation, only the parts relevant to this embodiment are shown, and are described in detail below: The zero-power control circuit in this embodiment includes a zero-reactive-force control module 101, a zero-power-force control module 102, an auxiliary power supply 103, and a subsequent circuit 104. The AC input terminal of the zero-reactive-force control module 101 is electrically connected to the AC power grid 105, the power output terminal of the zero-reactive-force control module 101 is electrically connected to the subsequent circuit 104, the status output terminal of the zero-reactive-force control module 101 is electrically connected to the status input terminal of the zero-power-force control module 102, the power input terminal of the auxiliary power supply 103 is electrically connected to the DC bus of the subsequent circuit 104, the control terminal of the auxiliary power supply 103 is electrically connected to the control output terminal of the zero-power-force control module 102, and the signal input terminal of the zero-power-force control module 102 is electrically connected to the DC side of the subsequent circuit 104. The zero-reactive-force control module 101 is configured to operate based on the status of the subsequent circuit 104. The system controls the state of its internal switching nodes. When the downstream circuit 104 enters the working mode, it controls its internal switching nodes to be in the first state, so that a main power path is formed between the downstream circuit 104 and the AC power grid 105. When the downstream circuit 104 is in the standby mode, it controls its internal switching nodes to be in the second state, so that the main power path formed between the downstream circuit 104 and the AC power grid 105 is disconnected and it enters the zero-power mode. The zero-power control module 102 is configured to acquire the working state of the downstream circuit 104. When the working state of the downstream circuit 104 meets the target working state, it controls the auxiliary power supply 103 to be turned off. When the downstream circuit 104 is in the zero-power mode, if a zero-power control signal is received, it controls the auxiliary power supply 103 to be turned off, so that the downstream circuit 104 enters the zero-power mode.

[0023] Specifically, when the downstream circuit enters the working mode, the zero reactive power control module controls its internal switching nodes to the first state, forming a conductive main power path between the downstream circuit and the AC grid. The AC grid can then supply power to the downstream circuit normally, supporting its full-power operation. When the downstream circuit is in standby mode, the zero reactive power control module controls its internal switching nodes to the second state, disconnecting the main power path between the downstream circuit and the AC grid. This cuts off the electrical connection between the reactive power components in the downstream circuit and the AC grid, eliminates reactive power losses in the main power circuit, and allows the downstream circuit to enter the zero reactive power mode.

[0024] When the downstream circuit is in zero-power mode, if the zero-power control module receives a zero-power control signal through its own signal input terminal, it will output a control command through its own control output terminal to control the auxiliary power supply to shut down, thereby eliminating the active power consumption and reactive power loss generated when the auxiliary power supply is working, and enabling the downstream circuit to enter zero-power mode. If the downstream circuit does not enter zero-power mode, the zero-power control module will always lock the shutdown authority of the auxiliary power supply and prohibit it from responding to the zero-power control signal, so as to avoid the abnormal situation of erroneous shutdown of the auxiliary power supply when the downstream circuit is working normally, and ensure the safety and reliability of the circuit operation.

[0025] Understandably, the auxiliary power supply is used to provide power to the control, drive and other functional units of the subsequent circuit. Its power input is taken from the DC bus of the subsequent circuit, and it can maintain the power supply capability through the holding voltage of the DC bus in zero reactive power mode. The subsequent circuit is the core power conversion and load circuit, which can realize the conversion of AC power to DC power to power external load devices.

[0026] The zero-power control circuit provided in this embodiment, through the cooperation of the zero-reactive-power control module and the zero-power-consumption control module, not only eliminates the reactive power loss of the main power circuit in the standby state, but also further eliminates the residual power consumption in the standby state by turning off the auxiliary power supply. At the same time, it eliminates the risk of malfunction during normal operation from the circuit architecture, and takes into account ultra-low standby power consumption, operational safety and device wake-up capability. It solves the technical pain point in the prior art that it is impossible to simultaneously take into account the elimination of reactive power loss, reduction of active power consumption and device availability.

[0027] exist Figure 1 Based on the provided zero-power control circuit, this embodiment also provides a detailed structural diagram of the zero-power control circuit, please refer to [link / reference needed]. Figure 2 In some embodiments, an uncontrolled rectifier unit 106 is also included; the power output terminal of the zero reactive power control module 101 includes a first power output terminal and a second power output terminal. The first power output terminal of the zero reactive power control module 101 is electrically connected to the subsequent circuit 104, the second power output terminal of the zero reactive power control module 101 is electrically connected to the input terminal of the uncontrolled rectifier unit 106, and the output terminal of the uncontrolled rectifier unit 106 is electrically connected to the DC bus of the subsequent circuit 104; wherein, when the internal switching node of the zero reactive power control module 101 is in the first state, an open circuit is formed between the uncontrolled rectifier unit 106 and the AC power grid 105; when the internal switching node of the zero reactive power control module 101 is in the second state, a closed circuit is formed between the uncontrolled rectifier unit 106 and the AC power grid 105.

[0028] Specifically, the zero-power control circuit also includes an uncontrolled rectifier unit, which is used to convert the AC power input from the AC grid into DC power to provide a micro-current to maintain power supply for the DC bus of the subsequent circuit in standby mode.

[0029] The power output terminals of the zero reactive power control module are divided into a first power output terminal and a second power output terminal, which are functionally independent. The two outputs correspond to different working scenarios of the subsequent circuits: the first power output terminal is the main power supply port, which is electrically connected to the main power unit of the subsequent circuit. It is used to transmit full-power AC power to the subsequent circuit in the working mode to support the full-power operation of the subsequent circuit. The second power output terminal is a dedicated standby power supply port, which is electrically connected to the input terminal of the uncontrolled rectifier unit. It is used to provide AC input to the uncontrolled rectifier unit in the standby mode. The output terminal of the uncontrolled rectifier unit is electrically connected to the DC bus of the subsequent circuit. It is used to output the rectified DC power to the DC bus to maintain the stability of the bus voltage.

[0030] In this embodiment, the internal switching node state of the zero reactive power control module synchronously realizes the linkage switching between the main power path and the power supply path of the uncontrolled rectifier unit. The specific working logic is as follows: When the internal switching nodes of the zero-var control module are in the first state (corresponding to the operating mode of the subsequent circuit), the zero-var control module, through the on / off configuration of the internal switching nodes, creates an open circuit between the uncontrolled rectifier unit and the AC grid. The uncontrolled rectifier unit receives no AC input and stops operating. At this time, the main power path of the subsequent circuit is normally connected, and the AC grid supplies power to the subsequent circuit through the main power path. The main power conversion unit of the subsequent circuit operates normally, providing a stable DC voltage to the DC bus. The uncontrolled rectifier unit does not need to participate in power supply, thus avoiding power supply conflicts between the uncontrolled rectifier unit and the main power conversion unit, and eliminating the additional power consumption and harmonic interference of the uncontrolled rectifier unit in its operating mode.

[0031] When the internal switching nodes of the zero-reactive power control module are in the second state (corresponding to the standby zero-reactive power mode of the subsequent circuit), the zero-reactive power control module, through the on / off configuration of the internal switching nodes, cuts off the main power path between the main power unit of the subsequent circuit and the AC power grid, while simultaneously establishing a path between the uncontrolled rectifier unit and the AC power grid. The uncontrolled rectifier unit then connects to the AC power grid and starts working. At this time, the AC power from the AC power grid is input to the uncontrolled rectifier unit through the second power output terminal. After being converted to DC power by the uncontrolled rectifier unit, it is output to the DC bus of the subsequent circuit, providing a microampere-level standby sustaining current for the DC bus, offsetting the leakage current of the bus capacitor, and maintaining the bus voltage within the preset stable range. This design ensures the input power supply capability of the auxiliary power supply, providing a hardware foundation for the remote wake-up of the module, while avoiding the connection of reactive power devices in the main power circuit and generating no additional reactive power loss.

[0032] Furthermore, in Figure 2 Based on the provided zero-power control circuit, this embodiment also provides a partial structural diagram of another refined zero-power control circuit. Please refer to the following for details. Figure 3In some embodiments, the zero-reactive-force control module 101 includes a main zero-reactive-force control unit 1011 and an auxiliary zero-reactive-force control unit 1012. The first terminal of the main zero-reactive-force control unit 1011 and the first terminal of the auxiliary zero-reactive-force control unit 1012 together constitute the AC input terminal of the zero-reactive-force control module 101. The second terminal of the main zero-reactive-force control unit 1011 and the second terminal of the auxiliary zero-reactive-force control unit 1012 are connected in parallel to form the first power output terminal of the zero-reactive-force control module 101. The third terminal of the auxiliary zero-reactive-force control unit 1012 forms the second power output terminal of the zero-reactive-force control module 101. When the internal switching node of the zero-reactive-force control module 101 is in the first state, the internal switching node of the main zero-reactive-force control unit 1011 is closed, and the normally open contact of the internal switch of the auxiliary zero-reactive-force control module 101 is closed. When the internal switching node of the zero-reactive-force control module 101 is in the second state, the internal switching node of the main zero-reactive-force control unit 1011 is open, and the normally closed contact of the internal switch of the auxiliary zero-reactive-force control module 101 is closed.

[0033] Correspondingly, the main zero-reactive power control unit is a high-current main switching unit, primarily responsible for the full-power energy transmission of the main power circuit in operating mode and the complete disconnection of the main power circuit in standby mode. The auxiliary zero-reactive power control unit is a dual-contact mutually exclusive switching unit, with built-in mutually exclusive normally open and normally closed contacts, primarily responsible for switching the power supply link between operating and standby modes, achieving hardware interlocking between the main power path and the standby rectifier circuit. Both units are synchronously controlled, and the on / off states of their internal switching nodes completely match the operating mode of the subsequent circuit. The specific operating logic is as follows: When the internal switching node of the zero-reactive power control module is in the first state (corresponding to the working mode of the subsequent circuit), the internal switching node of the main zero-reactive power control unit is closed, conducting the main power transmission link; at the same time, the normally open contact of the internal switch of the auxiliary zero-reactive power control unit is closed, forming a parallel connection with the main zero-reactive power control unit to assist in supporting the power transmission of the main power circuit. At this time, the normally closed contact of the auxiliary zero-reactive power control unit is simultaneously opened, completely cutting off the electrical connection between the second power output terminal and the AC grid, creating an open circuit between the uncontrolled rectifier unit and the AC grid, stopping the uncontrolled rectifier unit from working, fully matching the power supply link requirements of the working mode in the previous embodiment, avoiding power supply conflicts between the uncontrolled rectifier unit and the main power unit, and eliminating additional power consumption and harmonic interference.

[0034] When the internal switching node of the zero reactive power control module is in the second state (corresponding to the standby zero reactive power mode of the subsequent circuit), the internal switching node of the main zero reactive power control unit is disconnected, completely cutting off the main power path between the main power unit of the subsequent circuit and the AC power grid, eliminating the reactive power loss generated by the reactive power devices in the main power circuit; at the same time, the normally open contact of the internal switch of the auxiliary zero reactive power control unit is simultaneously disconnected, and the normally closed contact is closed, connecting the second power output terminal with the AC power grid, so that a path is formed between the uncontrolled rectifier unit and the AC power grid, and the uncontrolled rectifier unit starts to work, providing standby power supply to the DC bus of the subsequent circuit.

[0035] Furthermore, in Figure 3 Based on the provided zero-power control circuit, this embodiment also provides a detailed structural diagram of another zero-power control circuit, please refer to [link / reference needed]. Figure 4 In some embodiments, the AC input terminals of the zero-reactive power control module 101 include a first-phase input terminal, a second-phase input terminal, and a third-phase input terminal; the first power output terminal of the zero-reactive power control module 101 includes a first-phase output terminal, a second-phase output terminal, and a third-phase output terminal; the main zero-reactive power control unit 1011 includes a first main relay RLY1, a second main relay RLY2, a third main relay RLY3, and a fourth main relay RLY4; the auxiliary zero-reactive power control unit 1012 includes a first auxiliary relay RLY5, a second auxiliary relay RLY6, a first resistor R1, and a second resistor R2; the normally open contacts of the first main relay RLY1, the second main relay RLY2, and the first auxiliary relay RLY5 are connected in parallel and electrically connected to the first-phase input terminal. The second terminal of main relay RLY1, the second terminal of second main relay RLY2, and the second terminal of first resistor R1 are connected in parallel and electrically connected to the first phase output terminal. The second terminal of first auxiliary relay RLY5 is electrically connected to the first terminal of first resistor R1. The first terminal of third main relay RLY3, the first terminal of fourth main relay RLY4, and the normally open contact of second auxiliary relay RLY6 are connected in parallel and electrically connected to the second phase input terminal. The second terminal of third main relay RLY3, the second terminal of fourth main relay RLY4, and the second terminal of second resistor R2 are connected in parallel and electrically connected to the second phase output terminal. The second terminal of second auxiliary relay RLY6 is electrically connected to the first terminal of second resistor R2. The normally closed contact of second auxiliary relay RLY6 is electrically connected to the second power output terminal.

[0036] Specifically, the AC input terminal of the zero reactive power control module is a three-phase AC input port, including a first-phase input terminal, a second-phase input terminal, and a third-phase input terminal, which correspond to the three-phase lines of the three-phase AC power grid, respectively; the first power output terminal of the zero reactive power control module is a three-phase AC output port, including a first-phase output terminal, a second-phase output terminal, and a third-phase output terminal, which are connected to the three-phase main power unit of the subsequent circuit.

[0037] The main zero-voltage reactive power control unit includes a first main relay RLY1, a second main relay RLY2, a third main relay RLY3, and a fourth main relay RLY4. All four are single-pole single-throw power relays, with rated current carrying capacity matching the full-power operating requirements of the subsequent circuits. Their core function is to control the high-current switching of the main power circuit. Specifically, the first terminal of the first main relay RLY1 and the first terminal of the second main relay RLY2 are connected in parallel and electrically connected to the first phase input terminal; the second terminals of the first main relay RLY1 and the second terminal of the second main relay RLY2 are connected in parallel and electrically connected to the first phase output terminal. This dual-relay parallel architecture achieves high-current shunting of the main power circuit, improves the current carrying capacity and operational redundancy of the single-relay circuit, avoids overload damage to a single relay, and enhances the long-term reliability of the circuit. The first terminal of the third main relay RLY3 and the first terminal of the fourth main relay RLY4 are connected in parallel and then electrically connected to the input terminal of the second phase. The second terminal of the third main relay RLY3 and the second terminal of the fourth main relay RLY4 are connected in parallel and then electrically connected to the output terminal of the second phase. Consistent with the dual-relay architecture of the first phase, this achieves high-reliability on / off control of the second phase main power circuit. The input terminal and the output terminal of the third phase are directly electrically connected to form a common conduction path for the three-phase main power circuit.

[0038] The auxiliary zero reactive power control unit includes a first auxiliary relay RLY5, a second auxiliary relay RLY6, a first resistor R1, and a second resistor R2. The first auxiliary relay RLY5 and the second auxiliary relay RLY6 are both single-pole double-throw relays with built-in mutually exclusive normally open and normally closed contacts. Only one contact can be closed at a time, naturally possessing hardware interlocking characteristics. The first resistor R1 and the second resistor R2 are power-type current-limiting resistors used to suppress surge current during power-on and closing, achieving a soft start-up of the main power circuit. The specific connection relationships are as follows: the normally open contact of the first auxiliary relay RLY5 is electrically connected to the input terminal of the first phase; the second terminal of the first auxiliary relay RLY5 is electrically connected to the first terminal of the first resistor R1; and the second terminal of the first resistor R1 is electrically connected to the output terminal of the first phase, thus establishing the power-on soft-start circuit for the first phase and forming a parallel connection with the first phase main relay; the normally open contact of the second auxiliary relay RLY6 is electrically connected to the input terminal of the second phase; the second terminal of the second auxiliary relay RLY6 is electrically connected to the first terminal of the second resistor R2; and the second terminal of the second resistor R2 is electrically connected to the output terminal of the second phase, thus establishing the power-on soft-start circuit for the second phase and forming a parallel connection with the second phase main relay; the normally closed contact of the second auxiliary relay RLY6 is electrically connected to the second power output terminal of the zero reactive power control module, used for the on / off control of the uncontrolled rectifier unit power supply circuit in standby mode.

[0039] In this embodiment, all relays are synchronously controlled by the main control unit of the subsequent circuit, and their on / off states are completely matched with the working mode of the subsequent circuit. The specific working logic is as follows: When the internal switching nodes of the zero reactive power control module are in the first state (corresponding to the working mode of the subsequent circuit), the internal switching nodes of the first main relay RLY1, the second main relay RLY2, the third main relay RLY3, and the fourth main relay RLY4 are all closed, and the three-phase main power circuit is turned on; at the same time, the normally open contacts of the first auxiliary relay RLY5 and the second auxiliary relay RLY6 are closed, and the normally closed contacts are open.

[0040] In this state, during the power-on startup phase, the normally open contact of the auxiliary relay can be closed first to pre-charge the bus capacitor of the subsequent circuit through the first resistor R1 and the second resistor R2, suppressing the surge current during power-on and preventing damage to the subsequent power devices. After pre-charging is completed, all main relays are closed, the current-limiting resistor is short-circuited, and the circuit enters full-power operation mode. The AC grid supplies power to the subsequent circuit normally through the three-phase main power circuit. At the same time, the normally closed contact of the second auxiliary relay RLY6 opens, completely cutting off the connection between the second power output terminal and the AC grid, creating an open circuit between the uncontrolled rectifier unit and the AC grid. The uncontrolled rectifier unit stops working, avoiding power supply conflicts with the main power circuit and eliminating additional power consumption and harmonic interference.

[0041] When the internal switching nodes of the zero reactive power control module are in the second state (corresponding to the standby zero reactive power mode of the subsequent circuit), the internal switching nodes of the first main relay RLY1, the second main relay RLY2, the third main relay RLY3, and the fourth main relay RLY4 are all disconnected, completely cutting off the three-phase main power circuit. This completely isolates the reactive power components such as the power factor correction circuit and the inverter circuit in the main power unit of the subsequent circuit from the AC power grid, thus completely eliminating the reactive power loss generated by the main power circuit. At the same time, the normally open contacts of the first auxiliary relay RLY5 and the second auxiliary relay RLY6 are simultaneously disconnected, and the soft start circuits of the first and second phases are simultaneously cut off.

[0042] In this state, the normally closed contact of the second auxiliary relay RLY6 closes, connecting the second phase input terminal and the second power output terminal electrically, thus establishing a path between the uncontrolled rectifier unit and the AC power grid. The uncontrolled rectifier unit starts working, providing a microamp-level standby current to the DC bus of the subsequent circuit, offsetting the bus capacitor leakage current, maintaining bus voltage stability, providing input power to the auxiliary power supply, and ensuring the module's remote wake-up capability. Simultaneously, this standby power supply circuit is connected to the single-phase AC power grid only through the normally closed contact of the second auxiliary relay RLY6, without connecting to any reactive power components in the main power circuit, thus preventing additional reactive power losses.

[0043] This embodiment achieves highly reliable on / off control in high-power scenarios through a main circuit architecture with dual main relays in parallel. A single-pole double-throw auxiliary relay simultaneously enables both power-on soft start and standby power supply circuit switching, simplifying the circuit architecture. Furthermore, leveraging the inherent mutual exclusion characteristics of the single-pole double-throw relay, absolute interlocking between the main power circuit and the standby rectifier circuit is achieved at the hardware level, preventing the abnormal situation of both circuits conducting simultaneously. In standby mode, only a single-phase circuit provides sustaining power to the bus, solving the problem of bus voltage maintenance in zero-reactive-mode without generating reactive power loss, further enhancing the circuit's practicality, reliability, and safety.

[0044] exist Figure 2 Based on the provided zero-power control circuit, this embodiment also provides a detailed structural diagram of a zero-power control circuit, please refer to [link / reference needed]. Figure 5 In some embodiments, the uncontrolled rectifier unit 106 includes a third resistor R3, a first diode D1, and a second diode D2. The first end of the third resistor R3 is electrically connected to the second power output terminal, and the second end of the third resistor R3 is electrically connected to the cathode of the first diode D1 and the anode of the second diode D2, respectively. The anode of the first diode D1 is electrically connected to the positive terminal of the DC bus, and the cathode of the second diode D2 is electrically connected to the negative terminal of the DC bus.

[0045] Specifically, the uncontrolled rectifier unit includes a third resistor R3, a first diode D1, and a second diode D2. The first terminal of the third resistor R3 is electrically connected to the second power output terminal, and the second terminal of the third resistor R3 is electrically connected to the cathode of the first diode D1 and the anode of the second diode D2, respectively. The anode of the first diode D1 is electrically connected to the positive terminal of the DC bus, and the cathode of the second diode D2 is electrically connected to the negative terminal of the DC bus. The third resistor R3 is used for current limiting and surge suppression in the rectifier circuit. The first diode D1 and the second diode D2 work together to rectify the AC input and prevent backflow of power into the DC bus. The operating state of this uncontrolled rectifier unit is linked to the zero-var control module: when the internal switching node of the zero-var control module is in the first state, the uncontrolled rectifier unit is disconnected from the AC power grid and stops working; when the internal switching node of the zero-var control module is in the second state, the uncontrolled rectifier unit is connected to the AC power grid, rectifies and outputs DC power to the DC bus, maintains stable bus voltage, and provides input power to the auxiliary power supply.

[0046] In some embodiments, the zero-power control module 102 includes an isolation unit, a switching execution unit, and an enabling unit. The primary side of the isolation unit serves as the signal input terminal of the zero-power control module 102 and is electrically connected to the DC side of the subsequent circuit 104. The isolation unit is configured to receive a zero-power control signal and electrically isolate the signal. The control terminal of the switching execution unit is electrically connected to the secondary side of the isolation unit, and the output terminal of the switching execution unit serves as the control output terminal of the zero-power control module 102 and is electrically connected to the control terminal of the auxiliary power supply 103. The switching execution unit is configured to turn off the auxiliary power supply 103 when it is turned on. The enabling unit is connected in series between the secondary side of the isolation unit and the control terminal of the switching execution unit. The trigger terminal of the enabling unit serves as the state input terminal of the zero-power control module 102 and is electrically connected to the state output terminal of the zero-reactive power control module 101. The enabling unit is configured to control the conduction permission of the switching execution unit according to the working state of the subsequent circuit 104.

[0047] Specifically, the primary side of the isolation unit serves as the signal input terminal of the zero-power control module, electrically connected to the DC side of the subsequent circuit. The isolation unit is configured to receive externally input zero-power control signals and electrically isolate the signals, achieving safety isolation between the DC low-voltage control side and the AC high-voltage power side, avoiding electrical crosstalk between the high and low voltage sides, and meeting the safety design requirements of power equipment. The control terminal of the switch execution unit is electrically connected to the secondary side of the isolation unit. The output terminal of the switch execution unit serves as the control output terminal of the zero-power control module, electrically connected to the control terminal of the auxiliary power supply. The switch execution unit is configured to output a control command when it is turned on, forcibly turning off the auxiliary power supply, and is the core execution unit for zero-power operation. The enable unit is connected in series between the secondary side of the isolation unit and the control terminal of the switch execution unit. The trigger terminal of the enable unit serves as the status input terminal of the zero-power control module, electrically connected to the status output terminal of the zero-reactive power control module. The enable unit is configured to control the conduction permission of the switch execution unit according to the working state of the subsequent circuit, realizing safety interlocking for zero-power operation.

[0048] When the downstream circuit does not enter the zero-power mode, the enable unit remains locked, cutting off the control loop between the isolation unit and the switch execution unit. Regardless of whether the isolation unit receives the zero-power control signal, the switch execution unit cannot be turned on, thus preventing the abnormal situation of erroneous shutdown of the auxiliary power supply under normal working conditions from the hardware level. When the downstream circuit enters the zero-power mode, the enable unit switches to the unlocked state and turns on the control loop. At this time, if the isolation unit receives the zero-power control signal, the switch execution unit can be turned on normally, turning off the auxiliary power supply and enabling the downstream circuit to enter the zero-power mode, eliminating the standby residual power consumption caused by the auxiliary power supply.

[0049] Furthermore, this embodiment also provides a structural schematic diagram of a zero-power control module, please refer to the following for details. Figure 6In some embodiments, the isolation unit includes a PWM controller 1021, an isolation capacitor 1022, and an isolation transformer 1023. The power supply terminal of the PWM controller 1021 is electrically connected to the DC side of the subsequent circuit 104. The signal output terminal of the PWM controller 1021 is connected in series with the isolation capacitor 1022 and then electrically connected to the primary winding of the isolation transformer 1023. The secondary winding of the isolation transformer 1023 is electrically connected to the switching execution unit.

[0050] Specifically, the isolation unit includes a PWM controller, an isolation capacitor, and an isolation transformer. The power supply terminal of the PWM controller is electrically connected to the DC side of the subsequent circuit. The signal output terminal of the PWM controller is connected in series with the isolation capacitor and then electrically connected to the primary winding of the isolation transformer. The secondary winding of the isolation transformer is electrically connected to the switching execution unit.

[0051] The PWM controller receives zero-power control trigger commands and converts the DC power supply input from the DC side of the subsequent circuit into a PWM drive signal. The isolation capacitor blocks the DC component in the signal loop to prevent magnetic saturation of the isolation transformer and improves the anti-interference capability of the signal transmission. The isolation transformer is a safety-compliant isolation device that achieves electrical isolation between the DC low-voltage control side and the AC high-voltage power side. It couples the PWM drive signal from the primary side to the secondary side to provide an isolated trigger signal for the switching execution unit.

[0052] The operation of this isolation unit is completely synchronized with the zero-power control requirements: when a zero-power action needs to be triggered, the PWM controller starts and outputs a PWM drive signal, which is then transmitted through an isolation capacitor and an isolation transformer before being output to the switching execution unit; when there is no zero-power control requirement, the PWM controller does not output a drive signal, the isolation unit does not output a trigger signal, and the switching execution unit remains in the off state, without affecting the normal operation of the auxiliary power supply.

[0053] For further details, please refer to [link / reference]. Figure 6In some embodiments, the switching execution unit includes a first optocoupler 1024, a second optocoupler 1025, and a composite transistor module 1026; the light-emitting diode on the primary side of the first optocoupler 1024 is connected in series in the secondary winding circuit of the isolation transformer 1023, the collector of the phototransistor on the secondary side of the first optocoupler 1024 is electrically connected to the auxiliary power supply 103, and the emitter of the phototransistor on the secondary side of the first optocoupler 1024 is electrically connected to the enable unit and the first terminal of the composite transistor module 1026, respectively; the second The anode of the primary-side light-emitting diode of the second optocoupler 1025 is electrically connected to the auxiliary power supply 103. The cathode of the primary-side light-emitting diode of the second optocoupler 1025 is electrically connected to the second terminal of the composite transistor module 1026. The collector of the secondary-side phototransistor of the second optocoupler 1025 is electrically connected to the enable terminal of the auxiliary power supply 103. The emitter of the secondary-side phototransistor of the second optocoupler 1025 is electrically connected to the reference ground of the auxiliary power supply 103. The third terminal of the composite transistor module 1026 is grounded together with the output terminal of the enable unit.

[0054] Specifically, the first optocoupler is a second-stage signal isolation device used to receive the zero-power trigger signal output from the isolation transformer, further realizing safety isolation between the high and low voltage sides, and also serving as a trigger switch for the switching execution unit. The second optocoupler is an auxiliary power supply shutdown execution device used to directly control the potential state of the auxiliary power supply enable terminal. The composite transistor module is a signal amplification and controlled switching device, working with the enable unit to realize the control of the switching execution unit's conduction permission. The working logic of this switching execution unit is linked to the state of the enable unit and the trigger signal of the isolation unit: when the downstream circuit has not entered the zero-power mode, the enable unit is in a locked state, the conduction loop of the switching execution unit is cut off, and even if the first optocoupler receives a trigger signal, the second optocoupler does not operate, and the auxiliary power supply remains in normal operation; when the downstream circuit enters the zero-power mode and the enable unit is unlocked, if the first optocoupler receives the zero-power trigger signal output from the isolation transformer, the composite transistor module is saturated and conducts, driving the second optocoupler to work, pulling the enable terminal of the auxiliary power supply low to the reference ground potential, forcibly shutting off the auxiliary power supply, and causing the downstream circuit to enter the zero-power mode.

[0055] Based on the above embodiments, this embodiment further explains the source, transmission path and dual isolation design of the zero-power control signal, and solves the core technical difficulties of insulation safety and malfunction risk in the transmission of control signals across AC and DC sides.

[0056] In this embodiment, the zero-power control signal originates from the output socket of the charging module. The externally input zero-power control signal is first insulated on the DC side, then transmitted to the AC side through the internal communication line of the module, and then, after secondary electrical isolation through an optocoupler, drives the subsequent circuit to achieve the shutdown control of the auxiliary power supply.

[0057] As an optional implementation, the zero-power control module also includes a constant current source circuit, which is connected in series in the secondary circuit of the first optocoupler. When the zero-power control signal is transmitted to the AC side through double isolation, the secondary side of the optocoupler is turned on, driving the constant current source circuit to start working. The constant current source continuously provides a constant operating current to the primary side light-emitting diode (i.e., feedback diode) of the auxiliary power feedback optocoupler U8, turning on the secondary side of U8, pulling the potential of the COMP pin of the auxiliary power driver IC to ground potential, commanding the driver IC to output a zero duty cycle drive signal, stopping the power drive output, thereby stopping the auxiliary power supply from working, and the module enters the zero-power mode.

[0058] The core technical challenge addressed in this embodiment is that the zero-power control signal originates from the DC-side output socket of the module and ultimately acts on the AC-side auxiliary power control IC. The transmission path of the control signal crosses the DC low-voltage safety zone and the AC high-voltage power zone. To ensure the safety and compliance of the module's normal operation, reliable electrical isolation between the zero-power control signal and the auxiliary power control circuit is essential. To address this challenge, this embodiment employs two levels of insulation isolation on both the DC and AC sides of the control signal transmission path: on the DC side, an insulation structure isolates the control signal from the module's main power circuit; on the AC side, an optocoupler provides safety-compliant electrical isolation between the low-voltage control circuit and the high-voltage power circuit. This ensures reliable transmission of the control signal while fully meeting the safety design requirements of high-voltage equipment, avoiding safety risks caused by electrical crosstalk between the high and low voltage sides.

[0059] Furthermore, it's worth noting that, as an optional simplified implementation, the aforementioned constant current source circuit can be omitted. The zero-power control signal, after isolation transmission, directly pulls the COMP pin potential of the auxiliary power driver IC to ground via an optocoupler, achieving auxiliary power supply shutdown control and thus zero-power control. However, this simplified solution carries a risk of malfunction: if a falsely triggered zero-power control signal is input when the module is in normal operating mode, it will directly shut down the auxiliary power supply, causing abnormal module shutdown and uncontrolled damage to power devices, posing a serious operational safety hazard.

[0060] To address this risk, a normally closed relay is added to the transmission line of the zero-power control signal. The control terminal of the normally closed relay is electrically connected to the module's main control unit, and its contacts are connected in series in the transmission loop of the zero-power control signal, serving as a specific implementation of the enable unit. The risk avoidance logic of this embodiment is as follows: When the module is in normal operating mode, the main control unit controls the normally closed relay to open, cutting off the transmission loop of the zero-power control signal. Even if there is a falsely triggered zero-power control signal input, a complete signal loop cannot be formed, and the auxiliary power supply shutdown action cannot be triggered. This completely avoids the risk of malfunction of the zero-power control circuit during normal module operation from a hardware perspective. When the module enters zero-power mode, the main control unit controls the normally closed relay to close, conducting the transmission loop of the zero-power control signal. At this time, the zero-power control signal can be transmitted normally, triggering the auxiliary power supply shutdown action, allowing the module to enter zero-power mode.

[0061] The custom terms and abbreviations used in this specification are defined as follows: Zero reactive power: refers to the complete disconnection of the reactive components inside the charging module from the AC power grid when the charging module is in standby mode, thus eliminating reactive current loss on the grid side; Zero power consumption: This refers to the process where, when the charging module is in standby mode, in addition to achieving zero reactive power control, the auxiliary power supply that powers the module control and drive unit is turned off, further eliminating residual active power consumption in standby mode. Zero reactive power mode: refers to the standby working mode after the module performs zero reactive power control. In this mode, the active power of the module is ≤10W and the reactive power is <20Var. Zero power mode: refers to the ultra-low standby mode after the module performs zero power control. In this mode, the module's active power is <1W and reactive power is <10Var. COMP pin: This refers to the control port of the auxiliary power supply's built-in driver IC. By forcibly pulling the potential of this pin to ground, the driver IC can be commanded to output a zero-duty-cycle drive signal to stop driving the power switching devices and thus stop the auxiliary power supply from working.

[0062] Furthermore, for ease of understanding, this embodiment also provides a logic control diagram for a zero-power mode, such as... Figure 7As shown. The forward start-up process of zero-power mode is as follows: After the device completes the main power operation task, it stops the main power conversion and enters the standby state. At this time, the auxiliary power supply works normally, providing power to the main control, detection and drive units of the device. All relays are in the initial ready state. The device main control issues a standby control command, controlling the first main relay RLY1, the second main relay RLY2, the third main relay RLY3, the fourth main relay RLY4 of the main zero reactive power control unit, and the first auxiliary relay RLY5 and the second auxiliary relay RLY6 of the auxiliary zero reactive power control unit to disconnect completely, cutting off the main power path between the device's main power unit and the AC power grid, completely isolating the reactive power devices in the main power circuit from the AC power grid, eliminating reactive power loss in the standby state, and the device officially starts the zero reactive power mode. Simultaneously, the normally closed contact of the second auxiliary relay RLY6 closes, forming a path between the uncontrolled rectifier unit and the AC power grid, providing a micro-current to the DC bus of the subsequent circuit to maintain power supply, offsetting the leakage current of the bus capacitor, and maintaining the stability of the bus voltage.

[0063] After the main controller of the equipment confirms stable operation in zero reactive power mode, it receives the zero power consumption mode control signal. Based on the aforementioned forced interlocking logic, the zero power consumption control module (i.e., the process energy-saving control circuit) can only respond to the control signal when the equipment is in zero reactive power mode. Otherwise, the control authority is always locked and the shutdown action is not performed. The zero power consumption control module responds to the control signal and starts working. It completes the safety isolation transmission of the control signal through the isolation unit, the enable unit unlocks the control loop synchronously, the switch execution unit is turned on, the enable terminal potential of the auxiliary power supply is pulled low, the auxiliary power supply is forcibly stopped, and the equipment officially starts the zero power consumption mode, completing the ultra-low power standby control.

[0064] In this embodiment, the zero-power mode exit and device power-on process is divided into two trigger branches to accommodate the wake-up and power-on requirements of the device in different states: one is the direct power-on branch in zero-reactive-mode: when the device is in zero-reactive-mode but has not yet entered zero-power-mode, if a power-on wake-up command is received, the device main controller first controls the normally open contacts of the first auxiliary relay RLY5 and the second auxiliary relay RLY6 to close, forming a power-on soft-start circuit through the matching current-limiting resistor, pre-charging the DC bus capacitor to suppress the closing surge; after the pre-charging is completed, the main controller controls the first main relay RLY1, the second main relay RLY2, the third main relay RLY3, and the fourth main relay RLY4 to close, short-circuiting the pre-charging circuit, conducting the three-phase main power path, and the device exits the zero-reactive-mode and enters the normal working ready state. The second branch is the wake-up power-on branch in zero-power mode: When the device is in zero-power mode, if it receives a wake-up command to exit zero-power mode, the zero-power control module stops working, the switch execution unit is turned off, the pull-down action of the auxiliary power enable terminal is released, the auxiliary power supply obtains power from the DC bus and restarts working, restores power supply to each unit of the device, the device exits zero-power mode and returns to the zero reactive power mode ready state, and can then execute the above direct power-on process according to the power-on command.

[0065] In summary, the zero-power control circuit provided in this application embodiment is based on a zero-reactive-force control module and works in conjunction with an uncontrolled rectifier unit, an auxiliary power supply, and subsequent circuits. After the equipment enters standby mode, the zero-reactive-force control module first cuts off the main power path between the subsequent main power unit and the AC power grid, completely isolating the reactive power components inside the module from the power grid, thus enabling the equipment to enter a zero-reactive-force mode to eliminate reactive power losses on the power grid side. Only when the equipment is stably in a zero-reactive-force mode can the zero-power control module respond to the zero-power control signal and turn off the auxiliary power supply that powers the equipment control and drive units, enabling the equipment to enter a zero-power mode to eliminate residual active power consumption during standby. Through this design, a mandatory interlocking mechanism is established in terms of hardware architecture and timing, fundamentally avoiding the safety risk of accidentally turning off the auxiliary power supply during normal equipment operation. Meanwhile, this solution solves the safety challenges of transmitting control signals across AC and DC sides through DC-side insulation and AC-side dual-stage electrical isolation. The relay-linked mutual exclusion circuit design decouples the main power operating circuit from the standby maintenance circuit, achieving ultra-low power standby while retaining the device's remote wake-up and command response capabilities. This solution achieves ultra-low standby performance with active power <1W and reactive power <10Var in zero-power mode, meeting the relevant requirements of power grid reactive power management and energy conservation while ensuring the stability and safety of equipment operation. Furthermore, its overall architecture is simple, flexible, and widely adaptable.

[0066] Figure 8A schematic diagram of a charging pile provided by a second aspect of the present application is shown. As shown in the figure, the second aspect of the present application provides a charging pile A, which includes a zero-power control circuit 10 as described in any of the above claims.

[0067] Those skilled in the art will clearly understand that, for the sake of convenience and brevity, the above-described division of functional units and modules is merely an example. In practical applications, the above functions can be assigned to different functional units and modules as needed, that is, the internal structure of the device can be divided into different functional units or modules to complete all or part of the functions described above. The functional units and modules in the embodiments can be integrated into one processing unit, or each unit can exist physically separately, or two or more units can be integrated into one unit. The integrated unit can be implemented in hardware or as a software functional unit. Furthermore, the specific names of the functional units and modules are only for easy differentiation and are not intended to limit the scope of protection of this application. The specific working process of the units and modules in the above system can be referred to the corresponding process in the foregoing method embodiments, and will not be repeated here.

[0068] References to "one embodiment" or "some embodiments" in this specification mean that one or more embodiments of this application include a specific feature, structure, or characteristic described in connection with that embodiment. Therefore, phrases such as "in one embodiment," "in some embodiments," etc., appearing in different parts of this specification do not necessarily refer to the same embodiment, but rather mean "one or more, but not all, embodiments," unless otherwise specifically emphasized. The terms "comprising," "including," "having," and variations thereof mean "including but not limited to," unless otherwise specifically emphasized.

[0069] The above-described embodiments are only used to illustrate the technical solutions of this application, and are not intended to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this application, and should all be included within the protection scope of this application.

Claims

1. A zero-power control circuit, characterized in that, The system includes a zero-reactive-state control module, a zero-power-consumption control module, an auxiliary power supply, and a subsequent circuit. The AC input terminal of the zero-reactive-state control module is electrically connected to the AC power grid, the power output terminal of the zero-reactive-state control module is electrically connected to the subsequent circuit, the status output terminal of the zero-reactive-state control module is electrically connected to the status input terminal of the zero-power-consumption control module, the power input terminal of the auxiliary power supply is electrically connected to the DC bus of the subsequent circuit, the control terminal of the auxiliary power supply is electrically connected to the control output terminal of the zero-power-consumption control module, and the signal input terminal of the zero-power-consumption control module is electrically connected to the DC side of the subsequent circuit. The zero reactive power control module is configured to control the state of its internal switching nodes based on the operating state of the downstream circuit; wherein, when the downstream circuit enters the operating mode, it controls its internal switching nodes to be in a first state, so that a main power path is formed between the downstream circuit and the AC power grid; when the downstream circuit is in standby mode, it controls its internal switching nodes to be in a second state, so that the main power path formed between the downstream circuit and the AC power grid is disconnected and enters the zero reactive power mode; The zero-power control module is configured to acquire the operating state of the downstream circuit, and control the auxiliary power supply to turn off when the operating state of the downstream circuit meets the target operating state; wherein, when the downstream circuit is in zero reactive power mode, if a zero-power control signal is received, the auxiliary power supply is controlled to turn off so that the downstream circuit enters zero-power mode.

2. The zero-power control circuit as described in claim 1, characterized in that, It also includes an uncontrolled rectifier unit; the power output terminal of the zero reactive power control module includes a first power output terminal and a second power output terminal, the first power output terminal of the zero reactive power control module is electrically connected to the subsequent circuit, the second power output terminal of the zero reactive power control module is electrically connected to the input terminal of the uncontrolled rectifier unit, and the output terminal of the uncontrolled rectifier unit is electrically connected to the DC bus of the subsequent circuit; wherein, when the internal switching node of the zero reactive power control module is in the first state, an open circuit is formed between the uncontrolled rectifier unit and the AC power grid; when the internal switching node of the zero reactive power control module is in the second state, a closed circuit is formed between the uncontrolled rectifier unit and the AC power grid.

3. The zero-power control circuit as described in claim 2, characterized in that, The zero reactive power control module includes a main zero reactive power control unit and an auxiliary zero reactive power control unit. The first terminal of the main zero reactive power control unit and the first terminal of the auxiliary zero reactive power control unit together constitute the AC input terminal of the zero reactive power control module. The second terminal of the main zero reactive power control unit and the second terminal of the auxiliary zero reactive power control unit are connected in parallel to form the first power output terminal of the zero reactive power control module. The third terminal of the auxiliary zero reactive power control unit forms the second power output terminal of the zero reactive power control module. Specifically, when the internal switch node of the zero reactive power control module is in the first state, the internal switch node of the main zero reactive power control unit is closed, and the normally open contact of the internal switch of the auxiliary zero reactive power control module is closed; when the internal switch node of the zero reactive power control module is in the second state, the internal switch node of the main zero reactive power control unit is open, and the normally closed contact of the internal switch of the auxiliary zero reactive power control module is closed.

4. The zero-power control circuit as described in claim 3, characterized in that, The AC input terminals of the zero reactive power control module include a first phase input terminal, a second phase input terminal, and a third phase input terminal. The first power output terminal of the zero reactive power control module includes a first phase output terminal, a second phase output terminal, and a third phase output terminal. The main zero reactive power control unit includes a first main relay, a second main relay, a third main relay, and a fourth main relay. The auxiliary zero reactive power control unit includes a first auxiliary relay, a second auxiliary relay, a first resistor, and a second resistor. The first terminal of the first main relay, the first terminal of the second main relay, and the normally open contact of the first auxiliary relay are connected in parallel and electrically connected to the first phase input terminal. The second terminal of the first main relay, the second terminal of the second main relay, and the second terminal of the first resistor are connected in parallel and electrically connected to the first phase output terminal. The second terminal of the first auxiliary relay is electrically connected to the first terminal of the first resistor. The first terminal of the third main relay, the first terminal of the fourth main relay, and the normally open contact of the second auxiliary relay are connected in parallel and electrically connected to the second phase input terminal. The second terminal of the third main relay, the second terminal of the fourth main relay, and the second terminal of the second resistor are connected in parallel and electrically connected to the second phase output terminal. The second terminal of the second auxiliary relay is electrically connected to the first terminal of the second resistor. The normally closed contact of the second auxiliary relay is electrically connected to the second power output terminal.

5. The zero-power control circuit as described in claim 2, characterized in that, The uncontrolled rectifier unit includes a third resistor, a first diode, and a second diode. The first end of the third resistor is electrically connected to the second power output terminal, and the second end of the third resistor is electrically connected to the cathode of the first diode and the anode of the second diode, respectively. The anode of the first diode is electrically connected to the positive terminal of the DC bus, and the cathode of the second diode is electrically connected to the negative terminal of the DC bus.

6. The zero-power control circuit as described in claim 1, characterized in that, The zero-power control module includes an isolation unit, a switch execution unit, and an enable unit; The primary side of the isolation unit serves as the signal input terminal of the zero-power control module and is electrically connected to the DC side of the subsequent circuit. The isolation unit is configured to receive the zero-power control signal and electrically isolate the signal. The control terminal of the switch execution unit is electrically connected to the secondary side of the isolation unit. The output terminal of the switch execution unit serves as the control output terminal of the zero-power control module and is electrically connected to the control terminal of the auxiliary power supply. The switch execution unit is configured to turn off the auxiliary power supply when it is turned on. The enabling unit is connected in series between the secondary side of the isolation unit and the control terminal of the switching execution unit. The trigger terminal of the enabling unit serves as the state input terminal of the zero-power control module and is electrically connected to the state output terminal of the zero-reactive power control module. The enabling unit is configured to control the conduction permission of the switching execution unit according to the working state of the subsequent circuit.

7. The zero-power control circuit as described in claim 6, characterized in that, The isolation unit includes a PWM controller, an isolation capacitor, and an isolation transformer. The power supply terminal of the PWM controller is electrically connected to the DC side of the subsequent circuit. The signal output terminal of the PWM controller is connected in series with the isolation capacitor and then electrically connected to the primary winding of the isolation transformer. The secondary winding of the isolation transformer is electrically connected to the switching execution unit.

8. The zero-power control circuit as described in claim 7, characterized in that, The switching execution unit includes a first optocoupler, a second optocoupler, and a composite transistor module; The light-emitting diode on the primary side of the first optocoupler is connected in series with the secondary winding circuit of the isolation transformer. The collector of the phototransistor on the secondary side of the first optocoupler is electrically connected to the auxiliary power supply. The emitter of the phototransistor on the secondary side of the first optocoupler is electrically connected to the first terminal of the enabling unit and the composite transistor module, respectively. The anode of the primary-side light-emitting diode of the second optocoupler is electrically connected to the auxiliary power supply, the cathode of the primary-side light-emitting diode of the second optocoupler is electrically connected to the second terminal of the composite transistor module, the collector of the secondary-side phototransistor of the second optocoupler is electrically connected to the enable terminal of the auxiliary power supply, and the emitter of the secondary-side phototransistor of the second optocoupler is electrically connected to the reference ground of the auxiliary power supply. The third terminal of the composite transistor module is grounded together with the output terminal of the enable unit.

9. A charging pile, characterized in that, The charging pile includes a zero-power control circuit as described in any one of claims 1 to 8.

10. A zero-power control method, characterized in that, This invention relates to a zero-power control circuit, which includes a zero-reactive-state control module, an auxiliary power supply, and a subsequent circuit. The AC input terminal of the zero-reactive-state control module is electrically connected to the AC power grid, the power output terminal of the zero-reactive-state control module is electrically connected to the subsequent circuit, the status output terminal of the zero-reactive-state control module is electrically connected to the status input terminal of the zero-power control module, the power input terminal of the auxiliary power supply is electrically connected to the DC bus of the subsequent circuit, the control terminal of the auxiliary power supply is electrically connected to the control output terminal of the zero-power control module, and the signal input terminal of the zero-power control module is electrically connected to the DC side of the subsequent circuit. The zero reactive power control module controls the state of its internal switching nodes based on the operating state of the downstream circuit. Specifically, when the downstream circuit enters the operating mode, it controls its internal switching nodes to be in a first state to form a main power path between the downstream circuit and the AC power grid. When the downstream circuit is in standby mode, it controls its internal switching nodes to be in a second state to form a circuit break between the downstream circuit and the AC power grid and enter the zero reactive power mode. The zero-power control module acquires the operating state of the downstream circuit. When the operating state of the downstream circuit meets the target operating state, it controls the auxiliary power supply to be turned off. Specifically, when the downstream circuit is in zero-reactive-mode, if a zero-power control signal is received, the auxiliary power supply is controlled to be turned off so that the downstream circuit enters zero-power mode.

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