Soft start circuit

Abstract

The invention belongs to the technical field of circuits, and particularly relates to a soft start circuit which is characterized in that an A-phase switch group is connected with a first end of a two-phase rectifier bridge and a first end of an EMC module, a B-phase switch group is connected with a second end of the two-phase rectifier bridge and a second end of the EMC module, a third end of the EMC module is connected with a C phase, and a fourth end of the EMC module is connected with a fourth end of the EMC module. The No.4-No.6 ends of the EMC module are respectively connected with the No.1-No.3 ends of the three-phase PFC; and the three-phase PFC is also respectively connected with the two-phase rectifier bridge, the DC module and the auxiliary power supply. The soft start circuit is used for solving the problem that a traditional soft start circuit can only play a soft start role and has no effect on solving the problem of reactive power loss. And the problems of device increase and cost increase are also considered when additional circuits are added.

Description

Technical Field

[0001] The invention belongs to the technical field of circuits, and in particular relates to a soft start circuit. Background Art

[0002] At present, when the charging power supply is in standby mode, due to the existence of inductors and capacitors in the EMC filter circuit inside the power supply, there will be a large amount of reactive power loss during standby mode. With the increase of the power of the power module and the power of the entire pile, this reactive power loss will be greater and the impact will be more serious.

[0003] The prior art has the following deficiencies: The traditional soft start circuit has a single function and can only play a soft start function, but cannot solve the problem of reactive power loss in standby mode of charging power supply.

[0004] Adding additional circuits makes the functions more complex, and it is necessary to consider the power supply problem of the power-on wake-up circuit after the input is disconnected.

[0005] Adding circuits to the traditional soft-start circuit will result in more components and higher costs. Summary of the invention

[0006] The present invention provides a soft start circuit to solve the above problem.

[0007] The present invention is achieved through the following technical solutions: A soft start circuit, the circuit comprising a two-phase rectifier bridge, a three-phase PFC, an EMC module, a DC module, an auxiliary power supply, an A-phase switch group and a B-phase switch group; The A-phase switch group is respectively connected to terminal No. 1 of the two-phase rectifier bridge and terminal No. 1 of the EMC module, the B-phase switch group is respectively connected to terminal No. 2 of the two-phase rectifier bridge and terminal No. 2 of the EMC module, terminal No. 3 of the EMC module is connected to the C phase, terminals No. 4-6 of the EMC module are respectively connected to terminals No. 1-3 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.

[0008] Furthermore, the A-phase switch group 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, the other end of the resistor R1 is connected to the third end of the single-pole double-throw switch K4, the first end of the single-pole double-throw switch K4 is connected to the first end of the two-phase rectifier bridge, and the second end of the single-pole double-throw switch K4 is connected to the A-phase of the EMC module.

[0009] Furthermore, the B-phase switch group 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, the other end of the resistor R2 is connected to the third end of the single-pole double-throw switch K3, the first end of the single-pole double-throw switch K3 is connected to the second end of the two-phase rectifier bridge, and the second end of the single-pole double-throw switch K3 is connected to the B phase of the EMC module.

[0010] Furthermore, terminal 4 of the three-phase PFC is respectively connected to terminal 3 of the two-phase rectifier bridge, one end of the capacitor C1, terminal 1 of the DC module and terminal 1 of the auxiliary power supply, and terminal 5 of the three-phase PFC is respectively connected to terminal 4 of the two-phase rectifier bridge, the other end of the capacitor C1, terminal 2 of the DC module and terminal 2 of the auxiliary power supply.

[0011] Furthermore, in standby mode, the auxiliary power supply is provided with a working input voltage through a branch formed by connecting the third end of the single-pole double-throw switch K3 and the third end of the single-pole double-throw switch K4 to the first end thereof respectively, rectifying by a two-phase rectifier bridge, and limiting current by resistors R1 and R2.

[0012] Furthermore, in standby mode, since the third end of the single-pole double-throw switch K3 and the third end of the single-pole double-throw switch K4 are respectively connected to the first end thereof, and the control switch K1 and the control switch K2 are in the disconnected state, the input grid and the main power circuit of the power supply are in the disconnected state, thereby minimizing the overall reactive and active power losses of the power supply.

[0013] The beneficial effects of the present invention are: The present invention has the functions of reducing reactive power and active power loss of power supply in soft starting and standby states.

[0014] The present invention does not require external power supply when in standby mode, and is used to wake up the power supply. The power supply is processed automatically through input, which is more convenient for users to use.

[0015] Compared with the traditional soft-start circuit, the present invention adds a circuit for reducing standby loss and a circuit for waking up the power supply. The improved soft-start circuit has relatively fewer components, simpler control, and easier PCB layout and routing, while also reducing the cost of power supply products. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 It is a structural schematic diagram of the present invention. DETAILED DESCRIPTION

[0017] In the following description, specific details such as specific system structures, technologies, etc. are provided for the purpose of illustration rather than limitation, so as to provide a thorough understanding of the embodiments of the present application. However, it should be clear to those skilled in the art that the present application may 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 prevent unnecessary details from obstructing the description of the present application.

[0018] It should be understood that when used in this specification and the appended claims, the term "comprising" indicates the presence of described features, integers, steps, operations, elements and / or components, but does not exclude the presence or addition of one or more other features, integers, steps, operations, elements, components and / or groups thereof.

[0019] It should also be understood that the terms used in this application specification are only for the purpose of describing specific embodiments and are not intended to limit the application. As used in this application specification and the appended claims, the singular forms "a", "an" and "the" are intended to include plural forms unless the context clearly indicates otherwise.

[0020] The following is attached to this application specification Figure 1 , the technical solutions in the embodiments of the present application are clearly and completely described. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present application.

[0021] In the following description, many specific details are set forth to facilitate a full understanding of the present application, but the present application may also be implemented in other ways different from those described herein, and those skilled in the art may make similar generalizations without violating the connotation of the present application. Therefore, the present application is not limited to the specific embodiments disclosed below.

[0022] A soft start circuit, the circuit comprising a two-phase rectifier bridge, a three-phase PFC, an EMC module, a DC module, an auxiliary power supply, an A-phase switch group and a B-phase switch group; The A-phase switch group is respectively connected to terminal No. 1 of the two-phase rectifier bridge and terminal No. 1 of the EMC module, the B-phase switch group is respectively connected to terminal No. 2 of the two-phase rectifier bridge and terminal No. 2 of the EMC module, terminal No. 3 of the EMC module is connected to the C phase, terminals No. 4-6 of the EMC module are respectively connected to terminals No. 1-3 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.

[0023] Furthermore, the A-phase switch group 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, the other end of the resistor R1 is connected to the third end of the single-pole double-throw switch K4, the first end of the single-pole double-throw switch K4 is connected to the first end of the two-phase rectifier bridge, and the second end of the single-pole double-throw switch K4 is connected to the A-phase of the EMC module.

[0024] Furthermore, the B-phase switch group 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, the other end of the resistor R2 is connected to the third end of the single-pole double-throw switch K3, the first end of the single-pole double-throw switch K3 is connected to the second end of the two-phase rectifier bridge, and the second end of the single-pole double-throw switch K3 is connected to the B phase of the EMC module.

[0025] Furthermore, terminal 4 of the three-phase PFC is respectively connected to terminal 3 of the two-phase rectifier bridge, one end of the capacitor C1, terminal 1 of the DC module and terminal 1 of the auxiliary power supply, and terminal 5 of the three-phase PFC is respectively connected to terminal 4 of the two-phase rectifier bridge, the other end of the capacitor C1, terminal 2 of the DC module and terminal 2 of the auxiliary power supply.

[0026] When the module is in standby mode, the control switch K1 and the control switch K2 remain disconnected, and the single-pole double-throw switch K3 and the single-pole double-throw switch K4 remain connected to the first end. When the module is powered on for the first time, since the capacitor C1 is in a low-power state, the resistors R1 and R2 can limit the current and suppress the surge current.

[0027] In standby mode, the auxiliary power supply is provided with working input voltage through resistors R1 and R2, single-pole double-throw switches K3 and K4, and then rectified by a two-phase rectifier bridge. At this time, the auxiliary source only supplies power to a small number of devices that support power wake-up.

[0028] Since the main power circuit (including EMC1 and three-phase PFC) is cut off during standby mode, the standby reactive and active power losses are minimized while ensuring that the power supply can be awakened and operated at any time.

[0029] When receiving the power-on command, the single-pole double-throw switch K3 and the single-pole double-throw switch K4 disconnect the first end connection and connect to the second end. The resistors R1 and R2 suppress the surge current caused by the filter capacitor in the EMC1. After a delay, the control switch K1 and the control switch K2 are pulled in, and the main power circuit begins to be awakened and work normally. When the power module completes charging and switches from the working state to the standby state, the drive of the main power circuit is turned off first, and then the control switch K1 and the control switch K2 are disconnected. After a short delay, the single-pole double-throw switch K3 and the single-pole double-throw switch K4 disconnect the second end connection and connect to the first end, disconnecting the main power circuit, maintaining the normal operation of the auxiliary source circuit, and continue to wait for the power-on wake-up command.

[0030] Furthermore, in standby mode, the auxiliary power supply is provided with a working input voltage through a branch formed by connecting the third end of the single-pole double-throw switch K3 and the third end of the single-pole double-throw switch K4 to the first end thereof respectively, rectifying by a two-phase rectifier bridge, and limiting current by resistors R1 and R2.

[0031] Furthermore, in standby mode, since the third end of the single-pole double-throw switch K3 and the third end of the single-pole double-throw switch K4 are respectively connected to the first end thereof, and the control switch K1 and the control switch K2 are in the disconnected state, the input grid and the main power circuit of the power supply are in the disconnected state, thereby minimizing the overall reactive and active power losses of the power supply.

[0032] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principle of the present invention should 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, an A-phase switch group and a B-phase switch group; The A-phase switch group is respectively connected to terminal No. 1 of the two-phase rectifier bridge and terminal No. 1 of the EMC module, the B-phase switch group is respectively connected to terminal No. 2 of the two-phase rectifier bridge and terminal No. 2 of the EMC module, terminal No. 3 of the EMC module is connected to the C phase, terminals No. 4-6 of the EMC module are respectively connected to terminals No. 1-3 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.

2. A soft start circuit according to claim 1, characterized in that: The A-phase switch group 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, the other end of the resistor R1 is connected to the third end of the single-pole double-throw switch K4, the first end of the single-pole double-throw switch K4 is connected to the first end of the two-phase rectifier bridge, and the second end of the single-pole double-throw switch K4 is connected to the A-phase of the EMC module.

3. A soft start circuit according to claim 1, characterized in that: The B-phase switch group 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, the other end of the resistor R2 is connected to the third end of the single-pole double-throw switch K3, the first end of the single-pole double-throw switch K3 is connected to the second end of the two-phase rectifier bridge, and the second end of the single-pole double-throw switch K3 is connected to the B phase of the EMC module.

4. A soft start circuit according to claim 1, characterized in that: Terminal 4 of the three-phase PFC is respectively connected to terminal 3 of the two-phase rectifier bridge, one end of the capacitor C1, terminal 1 of the DC module and terminal 1 of the auxiliary power supply, and terminal 5 of the three-phase PFC is respectively connected to terminal 4 of the two-phase rectifier bridge, the other end of the capacitor C1, terminal 2 of the DC module and terminal 2 of the auxiliary power supply.

5. A soft start circuit according to claim 1, characterized in that: In standby mode, the auxiliary power supply provides working input voltage through a branch formed by connecting the third end of the single-pole double-throw switch K3 and the third end of the single-pole double-throw switch K4 to the first end respectively, rectifying by a two-phase rectifier bridge, and limiting current by resistors R1 and R2.

6. A soft start circuit according to claim 1, characterized in that: In standby mode, since the third end of the single-pole double-throw switch K3 and the third end of the single-pole double-throw switch K4 are respectively connected to the first end thereof, and the control switch K1 and the control switch K2 are in the disconnected state, the input grid and the main power circuit of the power supply are in the disconnected state, thereby minimizing the overall reactive and active power losses of the power supply.

Images