Soft start circuit
By designing a soft start circuit including a two-phase rectifier bridge, a three-phase PFC, an EMC module, a DC module and a switch group, the problem that traditional soft start circuits cannot reduce the standby loss of the charging power supply is solved, and low-loss and self-wake power supply work is achieved, simplifying the circuit structure and reducing costs.
Patent Information
- Application Number
- CN202422260708.2
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-09-14
- Publication Date
- 2025-07-18
- Estimated Expiration
- 2034-09-14
AI Technical Summary
Traditional soft-start circuits can only play a soft-start function and cannot solve the problem of standby reactive power loss of charging power supplies. Adding additional circuits will lead to increased devices and increased costs.
A soft start circuit including a two-phase rectifier bridge, a three-phase PFC, an EMC module, a DC module, an auxiliary power supply, a switch group I and a switch group II are designed. By disconnecting the main power circuit during standby, a resistor and a single-pole double-throw switch are used to form a branch to provide auxiliary power voltage, reducing reactive and active losses, and controlling switch switching during wake-up to achieve self-wake-up of the power supply.
While implementing the soft start function, it reduces the reactive and active losses in the standby state, simplifies the circuit structure, reduces the number of devices, reduces the cost, and wakes up the power supply without external power supply.
Smart Images
Figure CN223124783U_ABST
Abstract
Description
Technical Field
[0001] The utility model belongs to the technical field of circuits, and particularly relates to a soft start circuit. Background Art
[0002] At present, in the standby state of a charging power supply, due to the existence of inductors and capacitors in the internal EMC filtering circuit of the power supply, there will be a large amount of reactive power loss during standby. With the increase of the power of the power supply module and the power of the entire charging pile, this reactive power loss will be greater and the impact will be more serious.
[0003] The prior art has the following deficiencies:
[0004] The traditional soft start circuit has a single function and can only play a soft start function, and cannot solve the problem of reactive power loss in the standby state of the charging power supply.
[0005] Adding an additional circuit has a complex function, and it is necessary to consider the power supply problem of the startup wake-up circuit after the input is disconnected.
[0006] Adding a circuit on the basis of the traditional soft start circuit will lead to more components and higher costs. Summary of the Utility Model
[0007] The utility model provides a soft start circuit to solve the above problems.
[0008] The utility model is realized through the following technical solutions:
[0009] A soft start circuit, the circuit includes a two-phase rectifier bridge, a three-phase PFC, an EMC module, a DC module, an auxiliary power supply, phase A of the input power grid, switch group I, phase B of the input power grid, switch group II, and phase C of the input power grid;
[0010] Switch group I is respectively connected to the 1st terminal of the two-phase rectifier bridge and the 1st terminal of the EMC module, switch group II is respectively connected to the 2nd terminal of the two-phase rectifier bridge and the 2nd terminal of the EMC module, the 3rd terminal of the EMC module is connected to phase C of the input power grid, the 4th - 6th terminals of the EMC module are respectively connected to the 1st - 3rd terminals of the three-phase PFC, and the three-phase PFC is also respectively connected to the two-phase rectifier bridge, the DC module, and the auxiliary power supply.
[0011] Further, switch group I includes resistor R1, control switch K1, and single-pole double-throw switch K4. One end of resistor R1 is connected to phase A of the input power grid, the other end of resistor R1 is connected to the third terminal of the single-pole double-throw switch K4, the first terminal of the single-pole double-throw switch K4 is connected to the first terminal of the two-phase rectifier bridge, and the second terminal of the single-pole double-throw switch K4 is connected to phase A of the input power grid of the EMC module.
[0012] Further, the switch group II includes a resistor R2, a control switch K2, and a single-pole double-throw switch K3; one end of the resistor R2 is connected to the B phase of the input power grid, the other end of the resistor R2 is connected to the third terminal of the single-pole double-throw switch K3, the first terminal of the single-pole double-throw switch K3 is connected to the second terminal of the two-phase rectifier bridge, and the second terminal of the single-pole double-throw switch K3 is connected to the B phase of the input power grid of the EMC module.
[0013] Further, the 4th terminal of the three-phase PFC is respectively connected to the 3rd terminal of the two-phase rectifier bridge, one end of the capacitor C1, the 1st terminal of the DC module, and the 1st terminal of the auxiliary power supply, and the 5th terminal of the three-phase PFC is respectively connected to the 4th terminal of the two-phase rectifier bridge, the other end of the capacitor C1, the 2nd terminal of the DC module, and the 2nd terminal of the auxiliary power supply.
[0014] Further, during standby, the third terminals of the single-pole double-throw switch K3 and the single-pole double-throw switch K4 are respectively connected to their first terminals, rectified by the two-phase rectifier bridge, and the branch formed by the current limiting of the resistors R1 and R2 provides the working input voltage for the auxiliary power supply.
[0015] Further, during standby, since the third terminals of the single-pole double-throw switch K3 and the single-pole double-throw switch K4 are respectively connected to their first terminals, and the control switches K1 and K2 are in the off state, the input power grid is disconnected from the main power circuit of the power supply, minimizing the total reactive and active power losses of the power supply.
[0016] The beneficial effects of the present utility model are as follows:
[0017] The present utility model simultaneously has the functions of soft start and reducing the reactive and active power losses of the power supply in the standby state.
[0018] When the present utility model is in standby, it does not require external power supply to wake up the power supply work. The power supply is processed by itself through the input, which is more convenient for users.
[0019] Compared with the traditional soft start circuit, the present utility model adds a circuit for reducing standby losses and a circuit for waking up the power supply work. The improved soft start circuit has relatively fewer components, simpler control, and is easier to implement in the PCB layout and wiring. At the same time, it also reduces the cost of the power supply product. Description of the Drawings
[0020] Figure 1 It is a structural schematic diagram of the present utility model. Detailed Embodiments
[0021] In the following description, specific details such as specific system architectures, technologies, etc. are presented for the purpose of illustration rather than limitation, so as to thoroughly understand the embodiments of the present application. However, those skilled in the art should understand that the present application can also be implemented in other embodiments without these specific details. In other cases, detailed descriptions of well-known systems, devices, circuits, and methods are omitted to avoid unnecessary details from interfering with the description of the present application.
[0022] It should be understood that when used in this specification and the appended claims, the term "comprising" indicates the presence of the described features, wholes, steps, operations, elements, and / or components, but does not exclude the presence or addition of one or more other features, wholes, steps, operations, elements, components, and / or their combinations.
[0023] It should also be understood that the terms used in the specification of the present application are only for the purpose of describing specific embodiments and are not intended to limit the present application. As used in the specification of the present application and the appended claims, unless the context clearly indicates otherwise, the singular forms "a", "an", and "the" are intended to include the plural forms.
[0024] The following combines the appended Figure 1 to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments in the present application without creative efforts belong to the scope protected by the present application.
[0025] In the following description, many specific details are set forth in order to provide a thorough understanding of the present application, but the present application can also be implemented in other ways different from those described herein. Those skilled in the art can make similar extensions without departing from the connotation of the present application. Therefore, the present application is not limited by the specific embodiments disclosed below.
[0026] A soft start circuit, the circuit includes a two-phase rectifier bridge, a three-phase PFC, an EMC module, a DC module, an auxiliary power supply, switch group I and switch group II;
[0027] Switch group I is respectively connected to the No. 1 terminal of the two-phase rectifier bridge and the No. 1 terminal of the EMC module, switch group II is respectively connected to the No. 2 terminal of the two-phase rectifier bridge and the No. 2 terminal of the EMC module, the No. 3 terminal of the EMC module is connected to the C phase of the input power grid, the No. 4-6 terminals of the EMC module are respectively connected to the No. 1-3 terminals of the three-phase PFC, and the three-phase PFC is also respectively connected to the two-phase rectifier bridge, the DC module and the auxiliary power supply.
[0028] Further, the switch group I includes a resistor R1, a control switch K1, and a single-pole double-throw switch K4. One end of the resistor R1 is connected to the A phase of the input power grid, the other end of the resistor R1 is connected to the third terminal of the single-pole double-throw switch K4, the first terminal of the single-pole double-throw switch K4 is connected to the first terminal of the two-phase rectifier bridge, and the second terminal of the single-pole double-throw switch K4 is connected to the A phase of the input power grid of the EMC module.
[0029] Further, the switch group II includes a resistor R2, a control switch K2, and a single-pole double-throw switch K3. One end of the resistor R2 is connected to the B phase of the input power grid, the other end of the resistor R2 is connected to the third terminal of the single-pole double-throw switch K3, the first terminal of the single-pole double-throw switch K3 is connected to the second terminal of the two-phase rectifier bridge, and the second terminal of the single-pole double-throw switch K3 is connected to the B phase of the input power grid of the EMC module.
[0030] Further, the 4th terminal of the three-phase PFC is respectively connected to the 3rd terminal of the two-phase rectifier bridge, one end of the capacitor C1, the 1st terminal of the DC module, and the 1st terminal of the auxiliary power supply. The 5th terminal of the three-phase PFC is respectively connected to the 4th terminal of the two-phase rectifier bridge, the other end of the capacitor C1, the 2nd terminal of the DC module, and the 2nd terminal of the auxiliary power supply.
[0031] When the module is in standby, the control switch K1 and the control switch K2 remain open, and the single-pole double-throw switches K3 and K4 remain connected to the first terminal. When power is first applied, since the capacitor C1 is in a discharged state, the resistors R1 and R2 can limit the current and suppress the inrush current.
[0032] During standby, through the resistors R1 and R2, via the single-pole double-throw switches K3 and K4, and then rectified by the two-phase rectifier bridge, the input voltage for the operation of the auxiliary power supply is provided. At this time, the auxiliary power supply only supplies power to a small number of devices that support the power-on wake-up operation.
[0033] Since the main power circuit (including EMC1 and three-phase PFC) is cut off during standby, the standby reactive and active losses are minimized, and at the same time, the power supply can be woken up for operation at any time.
[0034] When a power-on instruction is received, the single-pole double-throw switch K3 and the single-pole double-throw switch K4 disconnect the connection of the first end and connect to the second end. At this time, the resistors R1 and R2 play a role in suppressing the inrush current caused by the filter capacitor in the EMC1. After a delay for a period of time, the control switch K1 and the control switch K2 are closed. At this time, the main power circuit starts to be awakened and works normally. When the power module completes charging and changes from the working state to the standby state, first turn off the drive of the main power circuit, then disconnect the control switch K1 and the control switch K2. After a short delay, the single-pole double-throw switch K3 and the single-pole double-throw switch K4 disconnect the connection of the second end and connect to the first end, disconnect the main power circuit, and keep the auxiliary power part of the circuit working normally, and continue to wait for the power-on wake-up instruction.
[0035] Further, during standby, the third ends of the single-pole double-throw switch K3 and the single-pole double-throw switch K4 are respectively connected to their first ends, rectified by a two-phase rectifier bridge, and the branches formed by the current limiting of the resistors R1 and R2 provide the working input voltage for the auxiliary power supply.
[0036] Further, during standby, since the third ends of the single-pole double-throw switch K3 and the single-pole double-throw switch K4 are respectively connected to their first ends, and the control switch K1 and the control switch K2 are in the off state, the input power grid is disconnected from the main power circuit of the power supply, minimizing the total reactive and active power losses of the power supply.
[0037] The above are only the preferred embodiments of the present invention, and are not intended to limit the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present invention shall be included in the protection scope of the present invention.
Claims
1. A soft start circuit, characterized in that, The circuit includes a two-phase rectifier bridge, a three-phase PFC, an EMC module, a DC module, an auxiliary power supply, phase A of the input power grid, switch group I, phase B of the input power grid, switch group II, and phase C of the input power grid; Switch group I is respectively connected to terminal 1 of the two-phase rectifier bridge and terminal 1 of the EMC module. Switch group II is respectively connected to terminal 2 of the two-phase rectifier bridge and terminal 2 of the EMC module. Terminal 3 of the EMC module is connected to phase C of the input power grid. Terminals 4-6 of the EMC module are respectively connected to terminals 1-3 of the three-phase PFC. The three-phase PFC is also respectively connected to the two-phase rectifier bridge, the DC module, and the auxiliary power supply.
2. The soft start circuit according to claim 1, wherein Switch group I includes resistor R1, control switch K1, and single-pole double-throw switch K4. One end of resistor R1 is connected to phase A of the input power grid. The other end of resistor R1 is connected to the third terminal of single-pole double-throw switch K4. The first terminal of single-pole double-throw switch K4 is connected to the first terminal of the two-phase rectifier bridge. The second terminal of single-pole double-throw switch K4 is connected to phase A of the input power grid of the EMC module.
3. The soft start circuit according to claim 1, wherein Switch group II includes resistor R2, control switch K2, and single-pole double-throw switch K3. One end of resistor R2 is connected to phase B of the input power grid. The other end of resistor R2 is connected to the third terminal of single-pole double-throw switch K3. The first terminal of single-pole double-throw switch K3 is connected to the second terminal of the two-phase rectifier bridge. The second terminal of single-pole double-throw switch K3 is connected to phase B of the input power grid of the EMC module.
4. The soft start circuit according to claim 1, wherein Terminal 4 of the three-phase PFC is respectively connected to terminal 3 of the two-phase rectifier bridge, one end of capacitor C1, terminal 1 of the DC module, and terminal 1 of the auxiliary power supply. Terminal 5 of the three-phase PFC is respectively connected to terminal 4 of the two-phase rectifier bridge, the other end of capacitor C1, terminal 2 of the DC module, and terminal 2 of the auxiliary power supply.
5. The soft start circuit according to claim 1, wherein During standby, the third terminals of single-pole double-throw switches K3 and K4 are respectively connected to their first terminals, and the two-phase rectifier bridge rectifies. The branches formed by the current limiting of resistor R1 and resistor R2 provide the working input voltage for the auxiliary power supply.
6. The soft start circuit according to claim 1, characterized in that, During standby, since the third terminals of single-pole double-throw switches K3 and K4 are respectively connected to their first terminals, and control switches K1 and K2 are in the off state, the input power grid is disconnected from the main power circuit of the power supply, minimizing the total reactive and active losses of the power supply to the greatest extent.