CN111478287A

CN111478287A - Charging pile switching power supply fault protection circuit and charging pile power supply

Info

Publication number: CN111478287A
Application number: CN202010226652.2A
Authority: CN
Inventors: 邹大中; 陈浩舟; 李勋; 邓华森
Original assignee: Electric Vehicle Service of Southern Power Grid Co Ltd
Current assignee: Electric Vehicle Service of Southern Power Grid Co Ltd
Priority date: 2020-03-27
Filing date: 2020-03-27
Publication date: 2020-07-31

Abstract

The application relates to a fill electric pile switching power supply fault protection circuit and fill electric pile power, the circuit includes: the overvoltage protection module is used for detecting an output voltage value of the charging pile switching power supply and outputting an overvoltage protection control signal when the output voltage value is greater than or equal to a preset first threshold value; the overvoltage protection output module is used for outputting a preset voltage value to a load based on the received overvoltage protection control signal; and the oblique wave compensation module is used for providing compensation current for the overvoltage protection output module when the output voltage value is greater than or equal to a preset second threshold value so as to reduce the voltage value output by the overvoltage protection output module to a load, and the second threshold value is greater than the first threshold value, so that the fault protection circuit of the charging pile switch power supply can still perform short circuit or overload fault protection on the charging pile switch power supply under the condition that the output voltage value of the charging pile switch power supply is greater than the maximum working voltage threshold value of the overvoltage protection output module.

Description

Charging pile switching power supply fault protection circuit and charging pile power supply

Technical Field

The invention relates to the technical field of charging piles, in particular to a charging pile switch power supply fault protection circuit and a charging pile power supply.

Background

With the rapid development of electric vehicle technology, various charging piles appear in people's daily life, and the development of charging pile technology becomes one of the key influencing factors of electric vehicle popularization.

However, the circuit structure complexity of the switching power supply chip in the conventional electric vehicle charging pile is higher, the difficulty of removing faults is higher, the charging pile is generally installed outdoors and is in a insolation environment for a long time, the large current in the charging process is serious in heating, the temperature in the charging pile is relatively higher, the insulating material of the equipment is easy to age, and the short circuit or overload condition is easy to occur in the charging pile. If can not discover in time and fill the inside short circuit of electric pile power or overload phenomenon, induce easily and fill electric pile power internal circuit and burn out or other serious problems, bring unnecessary economic loss and influence the user and use.

Disclosure of Invention

Therefore, it is necessary to provide a charging pile switching power supply fault protection circuit and a charging pile power supply, which can perform short circuit or overload fault protection on a switching power supply inside a charging pile power supply, in order to solve the problems in the background art.

An aspect of the application provides a fill electric pile switching power supply fault protection circuit for fill electric pile switching power supply short circuit or overload fault protection, the circuit includes:

the overvoltage protection module is used for detecting an output voltage value of the charging pile switching power supply and outputting an overvoltage protection control signal when the output voltage value is greater than or equal to a preset first threshold value;

the overvoltage protection output module is connected with the overvoltage protection module and used for receiving the overvoltage protection control signal and outputting a preset voltage value to a load according to the overvoltage protection control signal;

the ramp compensation module is connected between the overvoltage protection module and the overvoltage protection output module in series, and is used for providing compensation current for the overvoltage protection output module when the output voltage value is greater than or equal to a preset second threshold value so as to reduce the voltage value output by the overvoltage protection output module to a load, wherein the second threshold value is greater than the first threshold value.

In the above embodiment of the protection circuit for the fault of the charging pile switch power supply, the overvoltage protection module is arranged to detect the output voltage value of the charging pile switch power supply, and output the overvoltage protection control signal when the output voltage value of the charging pile switch power supply is greater than or equal to the preset first threshold value, so that the overvoltage protection output module outputs the preset voltage value to the load according to the received overvoltage protection control signal, thereby avoiding overlarge output voltage value of the charging pile switch power supply caused by short circuit or overload inside the charging pile switch power supply, avoiding the problem of burning or other serious circuits inside the charging pile power supply, and avoiding unnecessary economic loss and influencing the use of users. Because the work of the overvoltage protection module is limited by the maximum peak voltage, when the output voltage value of the charging pile switching power supply detected by the overvoltage protection module is greater than the maximum bearing voltage value of the overvoltage protection module, the overvoltage protection module can be damaged, and the oblique wave compensation module is arranged between the overvoltage protection module and the overvoltage protection output module in series, so that the oblique wave compensation module provides compensation current for the overvoltage protection output module when the output voltage value is greater than or equal to a preset second threshold value, the voltage value output by the overvoltage protection output module to a load is reduced, and the charging pile switching power supply fault protection circuit can still perform short circuit or overload fault protection on the charging pile switching power supply under the condition that the output voltage value of the charging pile switching power supply is greater than the maximum working voltage threshold value of the overvoltage protection output module. Because overvoltage protection module when detecting the short circuit or the overload trouble of filling electric pile switching power supply, overvoltage protection output module still exports suitable magnitude of voltage to the load for fill electric pile power supply can normally supply power to the load when short circuit or the overload condition appears in the power supply circuit.

In one embodiment, the ramp compensation module includes a ramp compensation resistor, one end of the ramp compensation resistor is connected to the overvoltage protection module, and the other end of the ramp compensation resistor is connected to the third connection terminal of the first switch unit.

In the charging pile switching power supply fault protection circuit in the above embodiment, one end of the ramp compensation resistor is connected to the overvoltage protection module, and the other end of the ramp compensation resistor is connected to the third connection end of the first switch unit. When the output voltage value of the charging pile switching power supply detected by the overvoltage protection module is greater than the maximum bearing voltage value of the overvoltage protection module, the overvoltage protection module is set to provide compensation current for the overvoltage protection output module through the ramp compensation resistor so as to reduce the voltage value output by the overvoltage protection output module to a load, so that the charging pile switching power supply fault protection circuit can still perform short circuit or overload fault protection on the charging pile switching power supply under the condition that the output voltage value of the charging pile switching power supply is greater than the maximum working voltage threshold value of the overvoltage protection output module.

In one embodiment, the ramp compensation module further includes a first energy storage capacitor, one end of the first energy storage capacitor is connected to the input end of the ramp compensation resistor, and the other end of the first energy storage capacitor is grounded. When the overvoltage protection module provides compensation current for the overvoltage protection output module through the ramp compensation resistor, the first energy storage capacitor is charged; when the overvoltage protection module stops outputting the compensation current signal, the first energy storage capacitor is charged to provide the compensation current for the overvoltage protection output module through the ramp compensation resistor, so that the situation that the power failure of the overvoltage protection module suddenly causes impact on the power supply of the ramp compensation module is avoided, and the power supply stability of the ramp compensation module is improved.

In one embodiment, the overvoltage protection output module includes:

the input end of the primary coil of the first transformer is connected with the input end of the charging pile switching power supply and used for receiving direct current, and the output end of the secondary coil of the first transformer is connected with the output end of the charging pile switching power supply and used for supplying power to a load;

a first connection end of the first switch unit is connected with the output end of the primary coil, and a second connection end of the first switch unit is connected with the overvoltage protection module and used for receiving the overvoltage protection control signal;

one end of the current-limiting resistor is connected with the third connecting end of the first switch unit, and the other end of the current-limiting resistor is grounded;

the first switch unit is conducted according to the received overvoltage protection control signal and is connected with an input power supply of the charging pile switch power supply and the current-limiting resistor, so that the output end of the secondary coil of the first transformer outputs a preset voltage value to a load.

In the charging pile switching power supply fault protection circuit in the above embodiment, by setting a first transformer, a first switching unit and a current-limiting resistor connected in series, a first connection end of the first switching unit is set to be connected with an output end of the primary coil, and a second connection end of the first switching unit is connected with the overvoltage protection module for receiving the overvoltage protection control signal; one end of the current-limiting resistor is connected with the third connecting end of the first switch unit, and the other end of the current-limiting resistor is grounded, so that the first switch unit is conducted according to the received overvoltage protection control signal and is connected with the input power supply of the charging pile switch power supply and the current-limiting resistor, and the output end of the secondary coil of the first transformer outputs a preset voltage value to a load. When the output voltage value of the charging pile switching power supply detected by the overvoltage protection module is larger than or equal to a preset first threshold value, an overvoltage protection control signal is output to enable the first switch unit to be conducted, so that the overvoltage protection output module outputs the preset voltage value to a load through the output end of the secondary coil of the first transformer, and the charging pile switching power supply is guaranteed to normally supply power to the load.

In one embodiment, the overvoltage protection output module further includes a transformer protection module connected in parallel between an input end and an output end of the primary winding of the first transformer, and the transformer protection module includes:

one end of the divider resistor is connected with the input end of the primary coil, and the other end of the divider resistor is connected with the output end of the primary coil;

and one end of the first energy storage capacitor is connected with the input end of the primary coil, and the other end of the first energy storage capacitor is connected with the output end of the primary coil.

In the charging pile switching power supply fault protection circuit in the above embodiment, the protection module includes a voltage dividing resistor and a first energy storage capacitor by setting a transformer, one end of the voltage dividing resistor is connected with the input end of the primary coil, the other end of the voltage dividing resistor is connected with the output end of the primary coil, one end of the first energy storage capacitor is connected with the input end of the primary coil, and the other end of the first energy storage capacitor is connected with the output end of the primary coil. The divider resistor and the first energy storage capacitor store energy when the first transformer is powered on and supply power to the first transformer when the first transformer is powered off, so that the phenomenon that power supply is discontinuous for a load when a power supply stops supplying power to the first transformer instantly is avoided, and the stability and reliability of power supply of the charging pile switch power supply are ensured.

In one embodiment, the transformer protection module further comprises:

the anode of the diode is connected with the output end of the primary coil, the cathode of the diode is connected with the output end of the divider resistor and the output end of the first energy storage capacitor, and the diode is used for preventing the divider resistor and the first energy storage capacitor from supplying power to the output end of the primary coil reversely.

In one embodiment, the charging pile switching power supply fault protection circuit further includes a soft start module, where the soft start module is connected to the overvoltage protection module, and is configured to restart the overvoltage protection module according to a preset cycle when the output voltage value is greater than or equal to a preset first threshold value, so that when a short circuit or an overload phenomenon is eliminated, the overvoltage protection module normally operates to perform short circuit or overload fault protection on the charging pile switching power supply.

In one embodiment, the soft start module comprises:

one end of the second energy storage capacitor is connected with the overvoltage protection module, and the other end of the second energy storage capacitor is grounded;

and one end of the current reducing resistor is connected with the overvoltage protection module and is connected with the input end of the second energy storage capacitor, and the other end of the current reducing resistor is connected with the input end of the charging pile switching power supply.

In the charging pile switch power supply fault protection circuit in the above embodiment, one end of the second energy storage capacitor is connected to the overvoltage protection module, and the other end of the second energy storage capacitor is grounded, so that when the overvoltage protection module is started, the second energy storage capacitor is charged, and current flowing through the current reducing resistor is reduced, so that the starting current of the overvoltage protection module is reduced, and energy loss in the starting process of the overvoltage protection module is reduced.

In one embodiment, the charging pile switching power supply fault protection circuit further includes a feedback regulation module connected to the overvoltage protection module, and the feedback regulation module includes:

the collector of the optical coupling triode is connected with the overvoltage protection module and used for providing a feedback voltage value for the overvoltage protection module, and the emitter of the optical coupling triode is grounded;

one end of the third energy storage capacitor is connected with the collector electrode of the optical coupling triode, and the other end of the third energy storage capacitor is grounded;

the overvoltage protection module adjusts the first threshold value based on the feedback voltage value, and controls the soft start module to start working based on the feedback voltage value.

In the charging pile switch power supply fault protection circuit in the above embodiment, the feedback regulation module is arranged to include an optical coupling triode and a third energy storage capacitor, and a collector of the optical coupling triode is connected with the overvoltage protection module and is used for providing a feedback voltage value to the overvoltage protection module, so that the overvoltage protection module adjusts the size of the first threshold value based on the feedback voltage value, and thus the overvoltage protection module works in a closed-loop environment, the size of the first threshold value can be adaptively adjusted, and the adaptive range of the charging pile switch power supply fault protection circuit is improved while short-circuit or overload fault protection is better performed. The overvoltage protection module controls the soft start module to start working based on the feedback voltage value, so that when a short circuit or overload fault in a power supply loop of the charging pile disappears, the overvoltage protection module can timely and normally start a short circuit or overload fault protection function, and the working stability and reliability of the charging pile switch power supply fault protection circuit are improved.

Another aspect of this application provides a fill electric pile power, include according to arbitrary this application embodiment fill electric pile switching power supply fault protection circuit for fill electric pile switching power supply short circuit or overload fault protection.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings needed to be used in the description of the embodiments are briefly introduced below, and it is obvious that the drawings in the following description are only some embodiments of the present application, and it is obvious for those skilled in the art to obtain drawings of other embodiments based on these drawings without any creative effort.

Fig. 1 is a schematic diagram of a charging pile switching power supply fault protection circuit according to a first embodiment of the present disclosure.

Fig. 2 is a schematic diagram of a charging pile switching power supply fault protection circuit according to a second embodiment of the present disclosure.

Fig. 3 is a schematic diagram of a charging pile switching power supply fault protection circuit according to a third embodiment of the present application.

Fig. 4 is a schematic diagram of a charging pile switching power supply fault protection circuit according to a fourth embodiment of the present disclosure.

Fig. 5 is a schematic diagram of a charging pile switching power supply fault protection circuit according to a fifth embodiment of the present disclosure.

Fig. 6 is a schematic diagram of an architecture of a charging pile switching power supply fault protection circuit provided in a sixth embodiment of the present application.

Fig. 7 is a schematic diagram of a charging pile switching power supply fault protection circuit according to a seventh embodiment of the present disclosure.

Fig. 8 is a schematic circuit diagram of a charging pile switching power supply fault protection circuit provided in an eighth embodiment of the present application.

Fig. 9 is a schematic circuit diagram of a charging pile switching power supply fault protection circuit provided in a ninth embodiment of the present application.

Fig. 10 is a schematic circuit diagram of a first power converter circuit in a charging pile switching power failure protection circuit according to a tenth embodiment of the present disclosure.

Fig. 11 is a schematic circuit diagram of a second power converter circuit in a charging pile switching power failure protection circuit according to an eleventh embodiment of the present disclosure.

Detailed Description

To facilitate an understanding of the present application, the present application will now be described more fully with reference to the accompanying drawings. Preferred embodiments of the present application are illustrated in the accompanying drawings. This application may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete.

Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. The terminology used herein in the description of the present application is for the purpose of describing particular embodiments only and is not intended to be limiting of the application. As used herein, the term "and/or" includes any and all combinations of one or more of the associated listed items.

Where the terms "comprising," "having," and "including" are used herein, another element may be added unless an explicit limitation is used, such as "only," "consisting of … …," etc. Unless mentioned to the contrary, terms in the singular may include the plural and are not to be construed as being one in number.

It will be understood that, although the terms first, second, etc. may be used herein to describe various elements, these elements should not be limited by these terms. These terms are only used to distinguish one element from another. For example, a first element could be termed a second element, and, similarly, a second element could be termed a first element, without departing from the scope of the present application.

In this application, unless otherwise expressly stated or limited, the terms "connected" and "connecting" are used broadly and encompass, for example, direct connection, indirect connection via an intermediary, communication between two elements, or interaction between two elements. The specific meaning of the above terms in the present application can be understood by those of ordinary skill in the art as appropriate.

In a charging pile switching power failure protection circuit 100 provided in an embodiment of the present application, as shown in fig. 1, the charging pile switching power failure protection circuit 100 is used for short-circuit or overload failure protection of a charging pile switching power, and the charging pile switching power failure protection circuit 100 includes an overvoltage protection module 10, an overvoltage protection output module 20, and a ramp compensation module 30. The overvoltage protection module 10 is configured to detect an output voltage value of the charging pile switching power supply, for example, the overvoltage protection module 10 may be configured to be connected to the charging pile switching power supply as an output end of the dc power supply 201, and the overvoltage protection module 10 is configured to output an overvoltage protection control signal when the output voltage value is greater than or equal to a preset first threshold value; the overvoltage protection output module 20 is connected to the overvoltage protection module 10, and is configured to receive the overvoltage protection control signal and output a preset voltage value to the load 202 according to the overvoltage protection control signal; the ramp compensation module 30 is connected in series between the overvoltage protection module 10 and the overvoltage protection output module 20, and the ramp compensation module 30 is configured to provide a compensation current to the overvoltage protection output module when the output voltage value is greater than or equal to a preset second threshold value, so as to reduce the voltage value output by the overvoltage protection output module 20 to the load 202, where the second threshold value is greater than the first threshold value.

Specifically, in the charging pile switching power supply fault protection circuit in the above embodiment, the overvoltage protection module 10 is arranged to detect the output voltage value of the charging pile switching power supply, and the overvoltage protection control signal is output when the output voltage value of the charging pile switching power supply is greater than or equal to the preset first threshold value, so that the overvoltage protection output module 20 outputs the preset voltage value to the load 202 according to the received overvoltage protection control signal, thereby avoiding that the output voltage value of the charging pile switching power supply is too large when a short circuit or an overload occurs inside the charging pile switching power supply, avoiding inducing the problem of burning or other serious problems of an internal circuit of the charging pile power supply, and avoiding bringing unnecessary economic loss and influencing the use of a user. Since the operation of the overvoltage protection module 10 is limited by the maximum peak voltage, when the output voltage value of the charging pile switching power supply detected by the overvoltage protection module 10 is greater than the maximum withstand voltage value of the overvoltage protection module 10, the overvoltage protection module 10 is damaged, by arranging the ramp compensation module 30 in series between the overvoltage protection module 10 and the overvoltage protection output module 20, the ramp compensation module 30 provides a compensation current to the overvoltage protection output module 20 when the output voltage value is greater than or equal to the preset second threshold value, so as to reduce the voltage value output by the overvoltage protection output module 20 to the load 202, so that when the output voltage value of the charging pile switching power supply is greater than the maximum working voltage threshold value of the overvoltage protection output module, fill electric pile switching power supply fault protection circuit and still can carry out short circuit or overload fault protection to filling electric pile switching power supply. When detecting a short circuit or overload fault of the charging pile switching power supply, the overvoltage protection output module 20 still outputs a proper voltage value to the load 202, so that the charging pile power supply can normally supply power to the load when the short circuit or overload condition occurs in a power supply loop.

Further, in a charging pile switching power failure protection circuit 100 provided in an embodiment of the present application, as shown in fig. 2, the overvoltage protection output module 20 includes a first transformer 21, a first switching unit 22, and a current limiting resistor 23. The input end of the primary coil of the first transformer 21 is connected with the input end of the charging pile switching power supply and used for receiving direct current, and the output end of the secondary coil of the first transformer 20 is connected with the output end of the charging pile switching power supply and used for supplying power to a load 202; a first connection end of the first switch unit 22 is connected with an output end of a primary coil of the first transformer 20, and a second connection end of the first switch unit 22 is connected with the overvoltage protection module 10 and used for receiving an overvoltage protection control signal sent by the overvoltage protection module 10; one end of the current limiting resistor 23 is connected with the third connection end of the first switch unit 22, and the other end of the current limiting resistor 23 is grounded; the first switch unit 22 is turned on according to the received overvoltage protection control signal and is connected to the input power of the charging pile switch power supply and the current limiting resistor 23, so that the output end of the secondary coil of the first transformer 21 outputs a preset voltage value to the load 202.

Specifically, in the charging pile switching power supply fault protection circuit in the above embodiment, by providing the first transformer 21, the first switch unit 22 and the current limiting resistor 23 connected in series, the first connection end of the first switch unit 22 is connected to the output end of the primary coil of the first transformer 21, and the second connection end of the first switch unit 22 is connected to the overvoltage protection module 10, and is configured to receive the overvoltage protection control signal; one end of the current limiting resistor 23 is connected to the third connection end of the first switch unit 22, and the other end of the current limiting resistor 23 is grounded, so that the first switch unit 22 is turned on according to the received overvoltage protection control signal and is connected to the input power supply of the charging pile switch power supply and the current limiting resistor 23, and the output end of the secondary coil of the first transformer 21 outputs a preset voltage value to the load 202. When the output voltage value of the charging pile switching power supply detected by the overvoltage protection module 10 is greater than or equal to the preset first threshold value, the overvoltage protection control signal is output to enable the first switch unit 22 to be switched on, so that the overvoltage protection output module 20 outputs the preset voltage value to the load 202 through the output end of the secondary coil of the first transformer 21, and the charging pile switching power supply is ensured to normally supply power to the load.

Further, in a charging pile switching power failure protection circuit 100 provided in an embodiment of the present application, as shown in fig. 3, the overvoltage protection output module 20 further includes a transformer protection module 24, and the transformer protection module 24 is connected in parallel between two ends of the primary coil of the first transformer 21, and is configured to store energy when the first transformer 21 is powered on and supply power to the first transformer 21 when the first transformer 21 is powered off.

Specifically, in the charging pile switching power supply fault protection circuit in the above embodiment, the transformer protection module 24 is arranged between the two ends of the primary coil of the first transformer 21, and is configured to store energy when the first transformer 21 is powered on and supply power to the first transformer 21 when the first transformer 21 is powered off, so that a phenomenon that power supply is discontinuous for the load 202 when the power supply stops supplying power to the first transformer 21 instantaneously is avoided, and stability and reliability of power supply of the charging pile switching power supply are ensured.

Further, in a charging pile switching power supply fault protection circuit 100 provided in an embodiment of the present application, as shown in fig. 4, the charging pile switching power supply fault protection circuit further includes a soft start module 40, where the soft start module 40 is connected to the overvoltage protection module 10, and is configured to restart the overvoltage protection module cyclically according to a preset cycle when an output voltage value detected by the overvoltage protection module 10 is greater than or equal to a preset first threshold, so that when a short circuit or an overload phenomenon is eliminated, the overvoltage protection module 10 normally operates to perform short circuit or overload fault protection on the charging pile switching power supply.

Further, in a charging pile switching power supply fault protection circuit 100 provided in an embodiment of the present application, as shown in fig. 5, the charging pile switching power supply fault protection circuit further includes a feedback regulation module 50, where the feedback regulation module 50 is connected to the overvoltage protection module 10, and is configured to provide a feedback voltage value to the overvoltage protection module 10, so that the overvoltage protection module 10 adjusts the magnitude of the first threshold based on the feedback voltage value, and controls the soft start module to start to operate based on the feedback voltage value.

Specifically, in the charging pile switching power supply fault protection circuit in the above embodiment, the feedback adjustment module 50 is arranged to provide a feedback voltage value to the overvoltage protection module 10, so that the overvoltage protection module 10 adjusts the size of the first threshold value based on the feedback voltage value, and thus the overvoltage protection module 10 works in a closed-loop environment, the size of the first threshold value can be adaptively adjusted, and the adaptive range of the charging pile switching power supply fault protection circuit 100 is increased while short-circuit or overload fault protection is better performed. For example, the climate difference between different regions is large, and if the charging pile switching power supply fault protection circuit 100 is suitable for a region with a high temperature, the magnitude of the first threshold value monitored by the overvoltage protection module can be adaptively increased by adjusting the feedback adjustment module 50, so that the overvoltage protection module 10 is prevented from being mistakenly short-circuited or overloaded for fault protection due to an excessively high ambient temperature, and the charging pile power supply outputs a relatively low voltage value, which affects the normal operation of the charging pile power supply. The overvoltage protection module 10 controls the soft start module to start working based on the feedback voltage value, so that when a short circuit or overload fault in a power supply loop of the charging pile disappears, the overvoltage protection module 10 can normally start a short circuit or overload fault protection function in time, and the working stability and reliability of the charging pile switch power supply fault protection circuit are improved. For example, when the feedback voltage value output by the feedback adjusting module 50 is smaller than or equal to a preset threshold value, the overvoltage protection module 10 controls the soft start module 40 to start working based on the feedback voltage value, and the soft start module 40 restarts the overvoltage protection module according to a preset cycle, so that when the short circuit or overload phenomenon is eliminated, the overvoltage protection module normally works to perform short circuit or overload fault protection on the charging pile switching power supply.

Further, in the charging pile switching power supply fault protection circuit 100 provided in an embodiment of the present application, as shown in fig. 6, the charging pile switching power supply fault protection circuit further includes a first power conversion module 60 connected in series between the dc power supply 201 and the input end of the charging pile switching power supply fault protection circuit 100, where the first power conversion module 60 is configured to convert an input voltage value of the charging pile switching power supply into a preset input voltage value and then output the preset input voltage value, so that the charging pile switching power supply can meet different requirements of charging voltage values of different application scenarios and different vehicle types.

Further, in the charging pile switching power supply fault protection circuit 100 provided in an embodiment of the present application, as shown in fig. 7, the charging pile switching power supply fault protection circuit further includes a second power conversion module 70 connected in series between an output end of the charging pile switching power supply fault protection circuit 100 and a load 202, where the second power conversion module 70 is configured to convert an output voltage value of the charging pile switching power supply into a preset output voltage value and then output the preset output voltage value, so that the charging pile switching power supply can meet different requirements of charging voltage values of different application scenarios and different vehicle types.

Further, in a charging pile switching power supply fault protection circuit 100 provided in an embodiment of the present application, as shown in fig. 8, a first switching unit in an overvoltage protection output module 20 is configured as a Metal Oxide Semiconductor Field Effect Transistor (MOSFET) Q1, the overvoltage protection output module 20 includes a first transformer T1, a MOSFET Q1 and a current limiting resistor R1 which are sequentially connected in series, a source of the MOSFET Q1 is connected to an output end of a primary coil of the first transformer T1, and a gate of the MOSFET Q1 is connected to the overvoltage protection module 10 for receiving the overvoltage protection control signal; one end of a current-limiting resistor R1 is connected with the drain of the MOSFET Q1, and the other end of the current-limiting resistor R1 is grounded, so that the MOSFET Q1 is conducted according to the received overvoltage protection control signal and is connected with an input power supply of the charging pile switching power supply and the current-limiting resistor R1, and the output end of the secondary coil of the first transformer T1 outputs a preset voltage value to the load 202.

Further, in the charging pile switching power failure protection circuit in the above embodiment, as shown in fig. 8, the slope compensation module 30 includes a slope compensation resistor R7, one end of the slope compensation resistor R7 is connected to the overvoltage protection module 10, the other end of the slope compensation resistor R7 is connected to the input end of the current limiting resistor R1, when the output voltage value of the charging pile switching power supply detected by the overvoltage protection module 10 is greater than the maximum withstand voltage value of the overvoltage protection module, the overvoltage protection module 10 is arranged to provide a compensation current to the current limiting resistor R1 in the overvoltage protection output module via the ramp compensation resistor R7, so as to reduce the voltage value output by the overvoltage protection output module 20 to the load, and under the condition that the output voltage value of the charging pile switching power supply is greater than the maximum working voltage threshold value of the overvoltage protection output module, fill electric pile switching power supply fault protection circuit and still can carry out short circuit or overload fault protection to filling electric pile switching power supply.

Further, in the charging pile switching power supply fault protection circuit in the above embodiment, as shown in fig. 8, the transformer protection module 24 includes a current limiting resistor R2 and a first energy storage capacitor, one end of the current limiting resistor R2 is connected to the input end of the primary coil of the first transformer T1, and the other end of the current limiting resistor R2 is connected to the output end of the primary coil of the first transformer T1; one end of the first energy storage capacitor is connected to the input end of the primary winding of the first transformer T1, and the other end of the first energy storage capacitor is connected to the output end of the primary winding of the first transformer T1.

Specifically, in the charging pile switching power supply fault protection circuit in the above embodiment, the transformer protection module 24 includes a current limiting resistor R2 and a first energy storage capacitor connected in parallel, one end of the current limiting resistor R2 is connected to an input end of a primary coil of the first transformer T1, the other end of the current limiting resistor R2 is connected to an output end of the primary coil of the first transformer T1, one end of the first energy storage capacitor is connected to an input end of a primary coil of the first transformer T1, and the other end of the first energy storage capacitor is connected to an output end of a primary coil of the first transformer T1. The first energy storage capacitor stores energy when the first transformer T1 is powered on and supplies power to the first transformer T1 when the first transformer T1 is powered off, so that the phenomenon that power supply is discontinuous for the load 202 when the power supply stops supplying power to the first transformer T1 instantly is avoided, and the stability and reliability of power supply of the charging pile switch power supply are ensured.

Further, in the charging pile switching power supply fault protection circuit in the above embodiment, as shown in fig. 8, the transformer protection module 24 further includes a diode D1, an anode of the diode D1 is connected to the output end of the primary winding of the first transformer T1, a cathode of the diode D1 is connected to both the output end of the first energy storage capacitor and the output end of the current limiting resistor R2, and the diode D1 is configured to prevent the first energy storage capacitor from supplying power reversely to the output end of the primary winding of the first transformer T1.

Further, in the charging pile switching power failure protection circuit in the above embodiment, as shown in fig. 8, the soft start module 40 includes a second energy storage capacitor and a current reducing resistor R3. One end of the second energy storage capacitor is connected with the overvoltage protection module 10, and the other end of the second energy storage capacitor is grounded; one end of the current reducing resistor R3 is connected with the overvoltage protection module 10 and is connected with the input end of the second energy storage capacitor, and the other end of the current reducing resistor R3 is connected with the input end of the charging pile switching power supply.

In the charging pile switching power supply fault protection circuit in the above embodiment, one end of the second energy storage capacitor is connected to the overvoltage protection module 10, and the other end of the second energy storage capacitor is grounded, so that when the overvoltage protection module 10 is started, the second energy storage capacitor is charged, the current flowing through the current reducing resistor R3 is reduced, the starting current of the overvoltage protection module 10 is reduced, and the energy loss in the starting process of the overvoltage protection module 10 is reduced.

Further, in the charging pile switching power failure protection circuit in the above embodiment, as shown in fig. 8, the feedback regulation module 50 includes a photo-coupling transistor Q2 and an energy storage capacitor C3. The collector of the optical coupling triode Q2 is connected with the overvoltage protection module 10, and the emitter of the optical coupling triode Q2 is grounded; one end of the energy storage capacitor C3 is connected with the collector of the photo-coupling triode Q2, and the other end of the energy storage capacitor C3 is grounded.

In the charging pile switching power supply fault protection circuit in the above embodiment, the feedback regulation module 50 is arranged to include the optical coupling triode Q2 and the energy storage capacitor C3, and the collector of the optical coupling triode Q2 is connected to the overvoltage protection module 10, so as to provide a feedback voltage value for the overvoltage protection module 10, and the overvoltage protection module 10 adjusts the size of the first threshold value based on the feedback voltage value, so that the overvoltage protection module 10 works in a closed-loop environment, and the size of the first threshold value can be adaptively adjusted, thereby improving the application range of the charging pile switching power supply fault protection circuit while better performing short-circuit or overload fault protection. The overvoltage protection module 10 controls the soft start module 40 to start working based on the feedback voltage value, so that when a short circuit or overload fault in a power supply loop of the charging pile disappears, the overvoltage protection module 10 can normally start a short circuit or overload fault protection function in time, and the working stability and reliability of the charging pile switch power supply fault protection circuit are improved.

Further, in the charging pile switch power failure protection circuit in the above embodiment, as shown in fig. 8, the second power conversion module 70 includes an inductor 1, a diode D, a zener diode D, a capacitor C, a resistor R, and an output end of a secondary coil of the first transformer T sequentially passes through the diode D and the inductor 1 to supply power to the load 202, an anode of the diode D is connected to an output end of the secondary coil of the first transformer T, a cathode of the diode D is connected to an input end of the inductor 1, a cathode of the zener diode D is connected to an input end of the inductor 1 via the resistor R, an anode of the zener diode D is grounded, an output end of the inductor 1 sequentially passes through the resistor R and the resistor R to be grounded, and a cathode of the zener diode D is connected to an input end of the resistor R via the capacitor C, so that the inductor 1, the resistor R, the zener diode D, the resistor R, and the resistor R form an energy buffer loop to prevent the load 202 from being interfered by external electromagnetic signals, the inductor 1 may supply power to the load when the first transformer T is suddenly powered off, and may further include other power conversion modules for outputting different voltage to meet different requirements.

In a charging pile switching power failure protection circuit 100 provided in an embodiment of the present application, as shown in fig. 9, the overvoltage protection module 10 may be configured to use one of control chips of the NCP1253 series. The chip comprises a voltage monitoring pin DRV, a voltage pin VCC, an output compensation pin CS, a feedback pin FB, a grounding pin GND and a pin NC. The terminal P6 and the terminal P7 are connected to the input voltage terminal of the charging pile switching power supply fault protection circuit 100, and the terminal P1, the terminal P2, the terminal P3, the terminal P4, and the terminal P5 are connected to a load to supply power to the load. The gate of the MOSFET Q1 is connected to the voltage monitoring pin DRV through a resistor R54 and a resistor R53 in sequence, the cathode of the diode D7 is connected to the input terminal of the resistor R53, and the anode of the diode D7 is connected to the output terminal of the resistor R53. The voltage pin VCC has a latched preset first threshold value OVP, when the overvoltage protection module 10 monitors that the voltage value of the voltage pin VCC is greater than or equal to the preset first threshold value OVP, the voltage monitoring pin DRV is controlled to output an overvoltage protection control signal, so that the MOSFET Q1 is turned on, and the current limiting resistor R1 divides the input voltage of the charging pile switch power supply fault protection circuit 100, so that the first transformer T1 outputs a fixed voltage value. For example, when the voltage on the voltage pin VCC exceeds 25.5V, the pulse inside the NCP1253 control chip immediately stops and the part locks. The NCP1253 control chip observes the feedback pin FB, when the feedback voltage value provided by the feedback pin FB to the NCP1253 control chip reaches 1.5V, the oscillator inside the NCP1253 control chip starts to reduce the switching frequency, when the feedback voltage value provided by the feedback pin FB to the NCP1253 control chip reaches 1.05V, the peak current set value of the NCP1253 control chip is frozen inside, and the frequency of the oscillator inside the NCP1253 control chip continues to be reduced, and can be reduced to 26 kilohertz (typical). When the NCP1253 control chip monitors that the voltage value on the voltage pin VCC is greater than or equal to the preset first threshold, the NCP1253 control chip is restarted cyclically according to a preset period (for example, 4ms), so that when the short circuit or overload phenomenon is eliminated, the NCP1253 control chip works normally to perform short circuit or overload fault protection on the charging pile switching power supply. The output compensation pin CS of the NCP1253 control chip is connected to the input end of the resistor R1 through the compensation resistor R55, and is configured to, when the NCP1253 control chip monitors that the voltage value on the voltage pin VCC is greater than or equal to a preset second threshold, where the second threshold is greater than the first threshold, output a compensation current signal to the current-limiting resistor R1 through the compensation resistor R55 by the NCP1253 control chip, so as to increase a voltage division value of the current-limiting resistor R1 on the input voltage value of the charging pile switching power supply fault protection circuit 100, and thereby reduce the voltage value output by the first transformer T1 to the load.

Further, in the charging pile switching power supply fault protection circuit in the above embodiment, as shown in fig. 9, the charging pile switching power supply fault protection circuit further includes a capacitor C71 and a resistor R57, one end of the capacitor C71 is connected to the output compensation pin CS of the NCP1253 control chip, and the other end of the capacitor C71 is grounded. One end of the resistor R57 is connected to the output end of the resistor R55, and the other end of the resistor R57 is grounded. The slope of the output compensation voltage value of the NCP1253 control chip can be set by setting the resistance values of the resistor R55 and the resistor R57. The capacitor C71 can improve the stability of the NCP1253 control chip for providing the voltage compensation signal to the resistor R1.

Further, in a charging pile switching power failure protection circuit provided in an embodiment of the present application, as shown in fig. 10, the first power conversion module 60 includes a connection terminal J3, a diode D9, a capacitor C44, an adjustable resistor RV1, a fuse PTC1, a transformer T3, a capacitor C43, a resistor R38, an inductor L, and a rectifier bridge YBS, a positive output terminal of the connection terminal J3 is connected to an input terminal of a primary winding of the first transformer T1 through the transformer T3 and the rectifier bridge YBS, a negative output terminal of the connection terminal J3 is connected to the ground through the fuse PTC1, the transformer T42, the inductor L, and the rectifier bridge YBS, the capacitor C44, the adjustable resistor RV1, and the capacitor C43 are respectively connected in parallel between the positive output terminal and the negative output terminal of the connection terminal J3, a voltage value output by the transformer T3 is converted into a suitable voltage value, and then output through the first transformer T1 and the capacitor C43, and an external electromagnetic wave signal input to the charging pile switch 44 may reduce interference of the charging pile switching signal.

Further, in a charging pile switching power supply fault protection circuit provided in an embodiment of the present application, as shown in fig. 11, the second power conversion module 70 is shown, and the charging pile switching power supply fault protection circuit in this embodiment provides three-way voltage output to a load via the second power conversion module 70, and now the operating principle of the second power conversion module 70 is exemplarily explained by the circuit operating principle of one-way voltage output, the terminal P1, the terminal P2, the terminal P3, the terminal P4, and the terminal P5 in this embodiment are respectively connected with the terminal P1, the terminal P2, and the terminal P2 in the embodiment shown in fig. 9, in this embodiment, the terminal P2 is connected to the load output + Vout 2 via the diode D2 and the diode 21, and the terminal P2 is grounded, wherein an anode of the diode D2 is connected to the terminal P2, a cathode of the diode D2 is connected to the input terminal P2, one end of the diode C2 is connected to a cathode of the diode D2, another end of the capacitor C2 is connected to the ground, and a capacitor C2 is connected to the capacitor R2, and a capacitor R2, a capacitor 2 is connected in parallel to the output voltage stabilizing the diode 2, so as to improve reliability of the bidirectional stabilizing voltage stabilizing output of the inductor 2.

In one embodiment of the present application, a charging pile power supply is provided, comprising a charging pile switching power supply fault protection circuit according to any of the embodiments of the present application, for short-circuit or overload fault protection of the charging pile switching power supply.

The technical features of the embodiments described above may be arbitrarily combined, and for the sake of brevity, all possible combinations of the technical features in the embodiments described above are not described, but should be considered as being within the scope of the present specification as long as there is no contradiction between the combinations of the technical features.

The above-mentioned embodiments only express several embodiments of the present invention, and the description thereof is more specific and detailed, but not construed as limiting the scope of the invention. It should be noted that, for a person skilled in the art, several variations and modifications can be made without departing from the inventive concept, which falls within the scope of the present invention. Therefore, the protection scope of the present patent shall be subject to the appended claims.

Claims

1. The utility model provides a fill electric pile switching power supply fault protection circuit for fill electric pile switching power supply short circuit or overload fault protection, the circuit includes:

2. The charging pile switching power supply fault protection circuit of claim 1, wherein the ramp compensation module comprises:

and one end of the ramp compensation resistor is connected with the overvoltage protection module, and the other end of the ramp compensation resistor is connected with the third connecting end of the first switch unit.

3. The charging pile switching power supply fault protection circuit of claim 2, wherein the ramp compensation module further comprises:

and one end of the first energy storage capacitor is connected with the input end of the ramp compensation resistor, and the other end of the first energy storage capacitor is grounded.

4. The charging pile switching power supply fault protection circuit of claim 3, wherein the overvoltage protection output module comprises:

the input end of the primary coil of the first transformer is connected with the input end of the charging pile switching power supply and used for receiving alternating current, and the output end of the secondary coil of the first transformer is connected with the output end of the charging pile switching power supply and used for supplying power to a load;

5. The charging pile switching power supply fault protection circuit of claim 4, wherein the overvoltage protection output module further comprises a transformer protection module connected in parallel between an input and an output of the primary winding of the first transformer, the transformer protection module comprising:

one end of the first energy storage capacitor is connected with the input end of the primary coil, the other end of the first energy storage capacitor is connected with the output end of the primary coil, and the first energy storage capacitor is used for storing energy when the first transformer is powered on and supplying power to the first transformer when the first transformer is powered off.

6. The charging pile switching power supply fault protection circuit of claim 5, wherein the transformer protection module further comprises:

7. The charging pile switching power supply fault protection circuit of any one of claims 1-6, further comprising:

and the soft start module is connected with the overvoltage protection module and used for circularly restarting the overvoltage protection module according to a preset period when the output voltage value is greater than or equal to a preset first threshold value.

8. The charging pile switching power supply fault protection circuit of claim 7, wherein the soft start module comprises:

9. The charging pile switching power supply fault protection circuit of claim 8, further comprising:

a feedback regulation module connected to the overvoltage protection module for providing a feedback voltage value to the overvoltage protection module, the feedback regulation module including:

the collector of the optical coupling triode is connected with the overvoltage protection module, and the emitter of the optical coupling triode is grounded;

10. A charging post power source, comprising:

a charging pile switching power supply fault protection circuit as claimed in any one of claims 1 to 9 for charging pile switching power supply short circuit or overload fault protection.