High-voltage protection circuit of charger power supply

Abstract

The utility model provides a high-voltage protection circuit of a charger power supply, which relates to the technical field of circuits and comprises a high-voltage starting control circuit, a high-voltage protection circuit and a low-voltage protection circuit, the overvoltage control circuit is used for closing output in an overvoltage state; the PWM control unit is used for receiving state signals of the high-voltage starting control circuit and the overvoltage control circuit; and the high-voltage starting control circuit and the overvoltage control circuit are respectively connected to the PWM control unit. According to the utility model, high-voltage protection can be carried out on the YDC180 guide rail type high-performance charger power supply circuit.

Description

Technical Field

[0001] The utility model relates to the technical field of circuits, in particular to a high-voltage protection circuit for a charger power supply. Background Art

[0002] The YDC180 rail-mounted high-performance charger power supply is a charging device designed for high-performance batteries. It can charge batteries quickly and safely, and is widely used in various occasions that require efficient and stable charging. The charger adopts high-efficiency switching power supply technology, which can minimize energy loss and improve charging efficiency. The charger adopts intelligent control technology, which can automatically identify the battery type and status, and automatically adjust the charging current and voltage to ensure that the battery is fully charged and not overcharged. Widely applicable, the charger is suitable for many types of batteries, such as lithium-ion batteries, lead-acid batteries, etc., and can meet the charging needs of different occasions. In a high-voltage environment, if the design of the charger power supply is defective, it may cause safety risks such as electrical sparks, short circuits or electric shocks. This requires that the charger should provide high-voltage protection when designing to ensure the stability and reliability of the equipment when running at high loads. Utility Model Content

[0003] The problem solved by the utility model is how to carry out high voltage protection on the power supply circuit of the YDC180 rail-type high-performance charger.

[0004] In order to solve the above problems, the utility model provides a high voltage protection circuit for a charger power supply, comprising

[0005] High voltage start-up control circuit: used to start the control circuit under high voltage input state;

[0006] Overvoltage control circuit: used to shut down the output in the event of overvoltage;

[0007] PWM control unit: used to receive status signals of the high-voltage startup control circuit and the overvoltage control circuit;

[0008] The high-voltage startup control circuit and the overvoltage control circuit are respectively connected to the PWM control unit.

[0009] Further, the high voltage startup control circuit includes a first resistor, a second resistor, a third resistor, a fourth resistor, a tenth resistor, a fifteenth resistor, a sixteenth resistor, a seventeenth resistor, an eighteenth resistor, a nineteenth resistor, a third diode, a sixth diode, a sixth MOS tube, a seventh MOS tube, a sixth capacitor and a ninth capacitor;

[0010] The first end of the first resistor and the first end of the tenth resistor are connected in parallel to the voltage input end, and the second end of the first resistor and the second resistor, the third resistor, the fourth resistor, the seventeenth resistor, and the eighteenth resistor are connected in series to the drain of the sixth MOS tube;

[0011] The second end of the tenth resistor is connected in series with the fifteenth resistor and the nineteenth resistor to the drain of the seventh MOS tube and the gate of the sixth MOS tube; the source of the sixth MOS tube is connected in parallel with the sixth capacitor and the ninth capacitor to the voltage input end of the PWM control unit;

[0012] The gate of the seventh MOS tube, the third diode and the sixteenth resistor are connected in parallel to the voltage input terminal of the PWM control unit, and the sixth diode, the gate of the sixth MOS tube and the drain of the seventh MOS tube are connected in parallel.

[0013] Further, the overvoltage control circuit includes a seventh resistor, a fortieth resistor, a forty-first resistor, a second diode, a fourteenth capacitor, a PWM control unit terminal and an LED unit;

[0014] The first end of the seventh resistor and the first end of the second diode are connected in parallel to the working voltage input end, and the second end of the seventh resistor and the LED unit are connected in series and connected in parallel to the forty-first resistor, the fourteenth capacitor, and the first end of the PWM control unit connection terminal and ground;

[0015] The second end of the second diode and the fortieth resistor are connected in series and connected in parallel with the forty-first resistor, the fourteenth capacitor and the second end of the connection terminal of the PWM control unit.

[0016] Furthermore, the PWM control unit adopts the control chip NCP1342.

[0017] The utility model adopts the above technical solution to achieve the following beneficial effects:

[0018] The utility model provides high voltage protection for the YDC180 rail-type high-performance charger power supply circuit by setting a high voltage startup control circuit and an overvoltage control circuit on the PWM control unit of the YDC180 rail-type high-performance charger power supply. The high voltage startup control circuit realizes the rapid startup of the power supply and reduces the power consumption by controlling the conduction and cutoff of two MOS tubes. The overvoltage control circuit protects the equipment from damage by cutting off the power output when the power output voltage exceeds the safety limit. It ensures that the output voltage will not be too high due to various faults or abnormal conditions. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1A schematic diagram of the structure of a high-voltage protection circuit of a charger power supply provided by an embodiment of the utility model;

[0020] Figure 2 A schematic diagram of a high-voltage startup control circuit in a high-voltage protection circuit of a charger power supply provided by an embodiment of the utility model;

[0021] Figure 3 This is a schematic diagram of an overvoltage control circuit in a high-voltage protection circuit of a charger power supply provided in an embodiment of the utility model. DETAILED DESCRIPTION

[0022] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and understandable, the specific embodiments of the present invention are described in detail below with reference to the accompanying drawings.

[0023] The following are specific embodiments of the present invention and the accompanying drawings to further describe the technical solution of the present invention, but the present invention is not limited to these embodiments. Example

[0024] This embodiment provides a high voltage protection circuit for a charger power supply, such as Figures 1 to 3 As shown, including:

[0025] High voltage start-up control circuit: used to start the control circuit under high voltage input state;

[0026] Overvoltage control circuit: used to shut down the output in the event of overvoltage;

[0027] PWM control unit: used to receive status signals of the high-voltage startup control circuit and the overvoltage control circuit;

[0028] The high voltage starting control circuit and the overvoltage control circuit are respectively connected to the PWM control unit.

[0029] See also Figure 2 , wherein the high voltage startup control circuit includes a first resistor, a second resistor, a third resistor, a fourth resistor, a tenth resistor, a fifteenth resistor, a sixteenth resistor, a seventeenth resistor, an eighteenth resistor, a nineteenth resistor, a third diode, a sixth diode, a sixth MOS tube, a seventh MOS tube, a sixth capacitor and a ninth capacitor;

[0030] The first end of the first resistor and the first end of the tenth resistor are connected in parallel to the voltage input end, and the second end of the first resistor and the second resistor, the third resistor, the fourth resistor, the seventeenth resistor, and the eighteenth resistor are connected in series to the drain of the sixth MOS tube;

[0031] The second end of the tenth resistor is connected in series with the fifteenth resistor and the nineteenth resistor to the drain of the seventh MOS tube and the gate of the sixth MOS tube; the source of the sixth MOS tube is connected in parallel with the sixth capacitor and the ninth capacitor to the voltage input end of the PWM control unit;

[0032] The gate of the seventh MOS tube, the third diode and the sixteenth resistor are connected in parallel to the voltage input terminal of the PWM control unit, and the sixth diode, the gate of the sixth MOS tube and the drain of the seventh MOS tube are connected in parallel.

[0033] Specifically, the power is turned on: when the power is just turned on, the sixth MOS tube is in the on state. Rectified voltage: the first resistor and the tenth resistor are connected after rectification, and these two resistors are used to divide the voltage. The sixth MOS tube is turned on: when the sixth MOS tube is turned on, the current will flow through the auxiliary winding of the main transformer. This current will generate a voltage, which is related to the breakdown voltage of the third diode. The third diode breaks down: when the voltage generated by the auxiliary winding of the main transformer is high enough, it will break down the third diode. The function of the third diode is to limit the voltage to a specific value. When the voltage exceeds this value, it will "break down" and allow current to flow. The seventh MOS tube is turned on: after the third diode breaks down, the voltage across it will turn on the seventh MOS tube. The sixth MOS tube is turned off: after the seventh MOS tube is turned on, it will change the state of the circuit, so that the sixth MOS tube is turned off. This is achieved by changing the gate voltage of the sixth MOS tube.

[0034] Specifically, power consumption is reduced: after the sixth MOS tube is turned off, the circuit enters a normal working state, and power consumption is reduced at this time. This is because in the startup phase, the conduction of the sixth MOS tube may generate large power consumption, while in the normal working state, the sixth MOS tube is turned off and power consumption is reduced. The high-voltage fast startup circuit realizes fast startup of the power supply and reduces power consumption by controlling the conduction and cutoff of the sixth MOS tube and the seventh MOS tube.

[0035] See also Figure 3 , wherein the overvoltage control circuit includes a seventh resistor, a fortieth resistor, a forty-first resistor, a second diode, a fourteenth capacitor, a PWM control unit terminal and an LED unit;

[0036] The first end of the seventh resistor and the first end of the second diode are connected in parallel to the working voltage input end, and the second end of the seventh resistor and the LED unit are connected in series and connected in parallel to the forty-first resistor, the fourteenth capacitor, and the first end of the PWM control unit connection terminal and ground;

[0037] The second end of the second diode and the fortieth resistor are connected in series and connected in parallel with the forty-first resistor, the fourteenth capacitor and the second end of the connection terminal of the PWM control unit.

[0038] Specifically, the overvoltage control circuit is used to cut off the power output when the power output voltage exceeds the safety limit, thereby protecting the device from damage. This mechanism is usually used in switching power supplies or DC power supplies to ensure that the output voltage is not too high due to various faults or abnormal conditions. The overvoltage control circuit consists of a second diode, a fortieth resistor, a forty-first resistor, a fourteenth capacitor, and a PWM control unit terminal. The control pin of the PWM control unit NCP1342. Working principle: When the power supply is working normally and the output voltage is within the normal range, the second diode will not conduct, so the PWM control unit terminal is also in a non-conducting state. The control pin of the PWM control unit NCP1342 receives a normal signal, and the power supply continues to output normally. When the power output voltage increases and exceeds the set value of the second diode, the second diode will begin to conduct, thereby changing the voltage at the PWM control unit terminal.

[0039] Specifically, after the second diode is turned on, the voltage divider circuit composed of the 40th resistor and the 41st resistor, and the filtering effect of the 14th capacitor provide an appropriate control signal to the PWM control unit terminal. When the control end of the PWM control unit terminal receives enough signals, the PWM control unit terminal will be turned on. This will cause the control pin of the PWM control unit NCP1342 to receive a low-level signal or a corresponding shutdown signal, thereby shutting down the power output. Once the overvoltage control circuit is triggered, the power output will be shut down, thereby protecting the connected loads and devices from damage caused by excessive voltage.

[0040] Among them, the PWM control unit adopts the control chip NCP1342.

[0041] Specifically, this power supply uses NCP1611A IC for PFC and NCP1342 IC for PWM, and adopts a PFC plus single-tube flyback topology.

[0042] The utility model provides high voltage protection for the YDC180 rail-type high-performance charger power supply circuit by setting a high voltage startup control circuit and an overvoltage control circuit on the PWM control unit of the YDC180 rail-type high-performance charger power supply. The high voltage startup control circuit realizes the rapid startup of the power supply and reduces the power consumption by controlling the conduction and cutoff of two MOS tubes. The overvoltage control circuit protects the equipment from damage by cutting off the power output when the power output voltage exceeds the safety limit. It ensures that the output voltage will not be too high due to various faults or abnormal conditions.

[0043] Although the disclosure is disclosed as above, the protection scope of the disclosure is not limited thereto. Those skilled in the art can make various changes and modifications without departing from the spirit and scope of the disclosure, and these changes and modifications will fall within the protection scope of the utility model.

Claims

1. A high voltage protection circuit for a charger power supply, characterized in that: include: High voltage start-up control circuit: used to start the control circuit under high voltage input state; Overvoltage control circuit: used to shut down the output in the event of overvoltage; PWM control unit: used to receive status signals of the high-voltage startup control circuit and the overvoltage control circuit; The high-voltage startup control circuit and the overvoltage control circuit are respectively connected to the PWM control unit; The high voltage startup control circuit includes a first resistor, a second resistor, a third resistor, a fourth resistor, a tenth resistor, a fifteenth resistor, a sixteenth resistor, a seventeenth resistor, an eighteenth resistor, a nineteenth resistor, a third diode, a sixth diode, a sixth MOS tube, a seventh MOS tube, a sixth capacitor and a ninth capacitor; The first end of the first resistor and the first end of the tenth resistor are connected in parallel to the voltage input end, and the second end of the first resistor and the second resistor, the third resistor, the fourth resistor, the seventeenth resistor, and the eighteenth resistor are connected in series to the drain of the sixth MOS tube; The second end of the tenth resistor is connected in series with the fifteenth resistor and the nineteenth resistor to the drain of the seventh MOS tube and the gate of the sixth MOS tube; the source of the sixth MOS tube is connected in parallel with the sixth capacitor and the ninth capacitor to the voltage input end of the PWM control unit; The gate of the seventh MOS tube, the third diode and the sixteenth resistor are connected in parallel to the voltage input terminal of the PWM control unit, and the sixth diode, the gate of the sixth MOS tube and the drain of the seventh MOS tube are connected in parallel.

2. The high voltage protection circuit of the charger power supply according to claim 1, characterized in that: The overvoltage control circuit includes a seventh resistor, a fortieth resistor, a forty-first resistor, a second diode, a fourteenth capacitor, a PWM control unit terminal and an LED unit; The first end of the seventh resistor and the first end of the second diode are connected in parallel to the working voltage input end, and the second end of the seventh resistor and the LED unit are connected in series and connected in parallel to the forty-first resistor, the fourteenth capacitor, and the first end of the PWM control unit connection terminal and ground; The second end of the second diode and the fortieth resistor are connected in series and connected in parallel with the forty-first resistor, the fourteenth capacitor and the second end of the connection terminal of the PWM control unit.

3. The high voltage protection circuit of the charger power supply according to claim 1, characterized in that: The PWM control unit adopts the control chip NCP1342.

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