阅读说明：本技术 一种直流供电保护装置及其方法 (Direct current power supply protection device and method thereof ) 是由 易水华 李贺 梅欢 万蒋亮 高欣 郑宏海 谢强 张高强 徐玮 高茜 许立燕 缪 于 2019-09-03 设计创作，主要内容包括：本发明涉及一种直流供电保护装置,由继电器[1]、反向二极管[2]、过流保护模块[3]、供电控制开关[4]、直流电源模块[5]、供电指示灯[6]、反极性供电指示灯[7]、正极性供电指示灯[8]及瞬态抑制二极管[9]组成,该装置接入直流稳压电源[10],即可确保给用电设备[11]的正确供电。还涉及一种直流供电保护方法。本发明可提高供电系统的可靠性、安全性和工作效率,电路容易搭建,成本低,可推广应用于大多数自动测试系统中。(The invention relates to a direct current power supply protection device, which consists of a relay [1], a reverse diode [2], an overcurrent protection module [3], a power supply control switch [4], a direct current power supply module [5], a power supply indicator lamp [6], a reverse polarity power supply indicator lamp [7], a positive polarity power supply indicator lamp [8] and a transient suppression diode [9], wherein the device is connected with a direct current stabilized voltage power supply [10], so that the correct power supply for electric equipment [11] can be ensured. And also relates to a direct current power supply protection method. The invention can improve the reliability, safety and working efficiency of the power supply system, has easy circuit construction and low cost, and can be popularized and applied to most automatic test systems.)

1. A direct current power supply protection device is composed of a relay [1], a reverse diode [2], an overcurrent protection module [3], a power supply control switch [4], a direct current power supply module [5], a power supply indicator lamp [6], a reverse polarity power supply indicator lamp [7], a positive polarity power supply indicator lamp [8] and a transient suppression diode [9], and the device is connected to a direct current stabilized voltage power supply [10] to realize correct and safe power supply for electric equipment [11 ];

the relay [1] adopts a double-path relay and is respectively used for synchronous on-off control of a direct current power supply positive line and a direct current power supply negative line, the power of the relay [1] is selected according to the load characteristics of electric equipment, the positive end of a control coil of the relay [1] is simultaneously connected with a reverse diode [2] and the negative end of a transient suppression diode [9], the negative end of the coil is connected with the output negative end of a direct current stabilized power supply [10] to form a coil working loop, the relay [1] is provided with two paths of contacts, each path of contact is provided with a middle point and a normally-on point, the two middle points of the relay [1] are respectively connected with the output positive end and the output negative end of the direct current stabilized power supply [10], and the two normally-on points of the relay [1] are respectively connected with the output positive end and;

the reverse diode [2] is used for forward voltage switch-on control and reverse voltage switch-off control of the relay [1], the positive end of the reverse diode is connected with the normally closed point of the internal relay of the overcurrent protection module [3], and the negative end of the reverse diode is connected with the positive end of the control coil of the relay [1] and the negative end of the transient suppression diode [9 ];

the transient suppression diode [9] is reversely connected in parallel at two ends of a coil of the relay [1], so that sudden change of inductive current is quickly and effectively prevented when the power supply control switch [4] is switched off, and the influence on a system is reduced;

the overcurrent protection module [3] consists of a current sensor, a relay and an acquisition driving circuit, the current sensor detects working current, the overcurrent protection module [3] can preset a current limiting value, when actual current is greater than the preset current limiting value, the power supply of the relay [1] is cut off, the current sensor of the overcurrent protection module [3] is connected to the positive output end of the direct current stabilized power supply [10], the middle point of the internal relay is connected with a normally open point of a power supply control switch [4], a normally closed point of the internal relay is connected with the positive output end of a reverse diode [2], the positive input end of the acquisition driving circuit is connected to the positive output end of the direct current power supply module [5], the negative end of a coil of the internal relay is grounded, and the output end of the acquisition driving circuit is connected with the;

the middle point of the power supply control switch [4] is connected with the positive end of a direct-current stabilized power supply [10] and is used for controlling the coil of the relay [1] to supply power to realize power supply control on the electric equipment [11 ];

the direct current power supply module [5] is used for providing working voltage for the overcurrent protection module [3], and the voltage range of the direct current power supply module depends on the electricity utilization characteristics of the overcurrent protection module [3 ];

the power supply indicator lamp [6], the reverse polarity power supply indicator lamp [7] and the positive polarity power supply indicator lamp [8] are unipolar indicator lamps, the power supply indicator lamp [6] is connected between the positive end of the direct current stabilized power supply [10] and the ground, the reverse polarity power supply indicator lamp [7] and the positive polarity power supply indicator lamp [8] are respectively connected between the positive end and the negative end of the direct current stabilized power supply [10] in parallel in a reverse direction and a forward direction, the power supply indicator lamp [6] is used for indicating the power supply state of electric equipment, and the reverse polarity power supply indicator lamp [7] and the positive polarity power supply indicator lamp [8] are used for indicating the power supply wiring polarity state of the accessed direct current stabilized power supply [.

2. A dc supply protection device according to claim 1, characterized in that the relay [1] uses DPST or DPDT.

3. A dc supply protection device according to claim 2, characterized in that the backward diode [2] is a backward isolated switching diode.

4. A dc supply protection device according to claim 3, characterized in that the transient suppression diode [9] is a schottky diode, whose unidirectional conductivity is formed by metal-semiconductor contact, and which switches fast.

5. A DC supply protection device according to claim 4, characterized in that the current sensor of the overcurrent protection module [3] is a Hall current sensor.

6. A DC supply protection device according to claim 5, characterized in that the supply control switch [4] is a manual control switch.

7. A DC supply protection device according to claim 6, characterized in that the operating voltage range of the DC power supply module [5] depends on the power consumption characteristics of the overcurrent protection module [3 ].

8. A dc power supply protection method using a dc power supply protection device according to any one of claims 1 to 7, comprising the steps of:

1) connecting a direct-current power supply protection device between a direct-current stabilized power supply [10] and electric equipment [11] in series;

2) the direct current power supply module [5] is started to provide working power supply for the overcurrent protection module [3], the direct current stabilized power supply [10] outputs direct current voltage, if the direct current stabilized power supply [10] and the electric equipment [11] are correctly connected, the positive polarity power supply indicator lamp [8] is on, and the reverse polarity power supply indicator lamp [7] is off, otherwise, the opposite is performed;

3) under the condition of correct wiring, a positive polarity power supply indicator lamp [8] is lightened, a power supply control switch [4] is manually switched on, the power supply voltage of a direct current stabilized power supply [10] enters a coil of a relay [1] through the power supply control switch [4], an overcurrent protection module [3] and a reverse diode [2] and forms a loop with the output negative terminal of the direct current stabilized power supply [10], at the moment, the coil of the relay [1] normally works, two contacts are attracted, the power supply indicator lamp [6] is lightened, the direct current stabilized power supply [10] normally supplies power to electric equipment [11], the overcurrent protection module [3] synchronously monitors the load of the electric equipment [11] in real time and carries out protection judgment, if the current exceeds a preset overcurrent protection value, a coil working power supply of the relay [1] is cut off through an internal relay, at the moment, a transient suppression diode [9] can quickly absorb sudden change inductive current generated by the coil of the relay [1] due to switch disconnection, reducing the impact on the system.

4) Under the condition of wrong wiring, a reverse polarity power supply indicator lamp [7] is lightened, a power supply control switch [4] is manually switched on, a power supply positive end of a direct current stabilized power supply [10] is connected to a coil negative end of a relay [1] and a positive end of a transient suppression diode [9] through a power supply negative line and then is connected to a negative end of a reverse diode [2], due to the reverse cut-off characteristic of the reverse diode [2], a power supply loop cannot be formed by the coil of the relay [1] at the moment, two contacts are in a disconnected state, the power supply indicator lamp [6] cannot be lightened, and an electric device [11] cannot be connected with reverse polarity voltage to play a role in reverse polarity power supply protection.

Technical Field

The invention belongs to the technical field of test and measurement, and relates to a power supply protection device for direct current power supply control and an implementation method thereof.

Background

When power is supplied to a dc power device for work or test, a power supply control device having a dc power supply control function is generally used to perform power supply and distribution control according to a work flow. At present, a connection mode of power supply control equipment and a direct-current stabilized power supply generally adopts a binding post, an error-proof design is avoided, and the condition that a positive line and a negative line are reversely connected is easy to occur during wiring. The direct current voltage with the reverse polarity is connected to the electric equipment, so that the electric equipment is damaged or even directly damaged, and great loss is caused. In addition, when the power supply is correct, the current of the power supply line may be overloaded due to the abnormal function of some component, such as the dc voltage-stabilized power supply, the power supply control device, the electrical equipment, or the power supply line, and if the current is not found and cut off in time, a large damage may be caused.

Because the output interfaces of the direct current stabilized power supply have different specifications, the power supply wiring of the direct current stabilized power supply can not be designed in an error prevention manner, and part of the direct current stabilized power supply does not have an overload protection function, so that the phenomena of reverse polarity power supply and power overload are easy to occur. Aiming at the potential safety hazards, the existing protection measures mainly comprise the following modes:

1) adopting simple error-proof design of color distinction: the power supply lines are distinguished by colors (if the positive lines are red and the negative lines are white), and the connection is carried out by manual judgment, so that the mode has potential safety hazards, the occurrence of operation errors cannot be avoided, the influence of human factors is large, and the mode cannot be used as a main error-preventing measure.

2) Adopting a simple error-proof design confirmed by multiple persons: the wiring correctness is confirmed by other personnel, potential safety hazards exist in the mode, errors cannot be avoided, the influence of human factors is large, and the mode cannot be used as a main error prevention measure.

3) The power supply line adopts a reverse isolation design: and a reverse isolation type diode is connected in series in one of the positive power supply line and the negative power supply line. The mode can prevent the electric equipment from being connected with reverse polarity voltage, but the phenomenon that the direct current stabilized voltage power supply is short-circuited through the collection ground when the power supply line is not isolated from the peripheral collection circuit. In addition, the mode has higher power requirement on the reverse isolation diode, and the forward conduction voltage drop exists when the reverse isolation diode works, so that the voltage of a power supply line is inaccurate.

4) Reverse parallel diode mode of power supply loop: the power utilization equipment with external direct current power supply is characterized in that a diode is reversely connected in parallel on a direct current stabilized power supply to prevent the positive and negative of the external direct current power supply from being reversely connected. If the diode is reversely connected, the diode can be over-current, the external power supply is short-circuited, and then the safety or other protection functions can be cut off, so that the electric equipment is protected. The protection mode needs to carry out rectifier diode model selection according to the characteristics of the power load, and plays a role only through fuse burning or overload of a protection circuit, so that the phenomenon of large current appears in a direct current stabilized voltage power supply and a power supply loop, and potential safety hazards exist.

In order to overcome the above disadvantages, it is necessary to take effective protection measures for the dc power supply.

Disclosure of Invention

The invention aims to provide a power supply protection device for direct current power supply control and an implementation method thereof, which can be connected into power supply control equipment and a circuit with a direct current power supply control function, are used for solving the problems of power supply wiring errors (such as reverse connection of positive and negative wires) easily occurring when the traditional direct current stabilized power supply supplies power to electric equipment and damage of the electric equipment caused by overload of the power, can set current protection according to the load characteristics of the electric equipment, realize the function of automatically cutting off the power supply by overcurrent protection, improve the safety of a power supply line and ensure the safety of the electric equipment.

The technical scheme of the invention is as follows:

a kind of direct current supply protective device, by the relay [1], backward diode [2], the overcurrent protection module [3], the power supply control switch [4], the direct current power module [5], the power supply pilot lamp [6], the reverse polarity power supply pilot lamp [7], the positive polarity power supply pilot lamp [8] and transient state inhibit the diode [9] to make up, the apparatus only needs to insert the direct current stabilized voltage power supply [10], can guarantee to the correct, safe power supply of the electrical equipment [11 ];

the relay [1] adopts a double-path relay and is respectively used for synchronous on-off control of a direct current power supply positive line and a direct current power supply negative line, the power of the relay [1] is selected according to the load characteristics of electric equipment, the positive end of a control coil of the relay [1] is simultaneously connected with a reverse diode [2] and the negative end of a transient suppression diode [9], the negative end of the coil is connected with the output negative end of a direct current stabilized power supply [10] to form a coil working loop, the relay [1] is provided with two paths of contacts, each path of contact is provided with a middle point and a normally-on point, the two middle points of the relay [1] are respectively connected with the output positive end and the output negative end of the direct current stabilized power supply [10], and the two normally-on points of the relay [1] are respectively connected with the output positive end and;

the reverse diode [2] is used for forward voltage switch-on control and reverse voltage switch-off control of the relay [1], the positive end of the reverse diode is connected with the normally closed point of the internal relay of the overcurrent protection module [3], and the negative end of the reverse diode is connected with the positive end of the control coil of the relay [1] and the negative end of the transient suppression diode [9 ];

the transient suppression diode [9] is reversely connected in parallel at two ends of a coil of the relay [1], so that sudden change of inductive current is quickly and effectively prevented when the power supply control switch [4] is switched off, and the influence on a system is reduced;

the overcurrent protection module [3] consists of a current sensor, a relay and an acquisition driving circuit, the current sensor detects working current, the overcurrent protection module [3] can preset a current limiting value, when actual current is greater than the preset current limiting value, the power supply of the relay [1] is cut off, the current sensor of the overcurrent protection module [3] is connected to the positive output end of the direct current stabilized power supply [10], the middle point of the internal relay is connected with a normally open point of a power supply control switch [4], a normally closed point of the internal relay is connected with the positive output end of a reverse diode [2], the positive input end of the acquisition driving circuit is connected to the positive output end of the direct current power supply module [5], the negative end of a coil of the internal relay is grounded, and the output end of the acquisition driving circuit is connected with the;

the middle point of the power supply control switch [4] is connected with the positive end of a direct-current stabilized power supply [10] and is used for controlling the coil of the relay [1] to supply power to realize power supply control on the electric equipment [11 ];

the direct current power supply module [5] is used for providing working voltage for the overcurrent protection module [3], and the voltage range of the direct current power supply module depends on the electricity utilization characteristics of the overcurrent protection module [3 ];

the power supply indicator lamp [6], the reverse polarity power supply indicator lamp [7] and the positive polarity power supply indicator lamp [8] are unipolar indicator lamps, the power supply indicator lamp [6] is connected between the positive end of the direct current stabilized power supply [10] and the ground, the reverse polarity power supply indicator lamp [7] and the positive polarity power supply indicator lamp [8] are respectively connected between the positive end and the negative end of the direct current stabilized power supply [10] in parallel in a reverse direction and a forward direction, the power supply indicator lamp [6] is used for indicating the power supply state of electric equipment, and the reverse polarity power supply indicator lamp [7] and the positive polarity power supply indicator lamp [8] are used for indicating the power supply wiring polarity state of the accessed direct current stabilized power supply [.

The relay [1] is characterized by adopting DPST or DPDT.

The reverse diode [2] is a reverse isolation type switch diode.

The transient suppression diode [9] is characterized in that a Schottky diode is adopted, unidirectional conductivity of the Schottky diode is formed by contacting metal and a semiconductor, and switching speed is high.

The overcurrent protection circuit is characterized in that a current sensor of the overcurrent protection module [3] is a Hall current sensor.

It is characterized in that the power supply control switch [4] is a manual control switch.

The DC power supply is characterized in that the working voltage range of the DC power supply module [5] depends on the power utilization characteristics of the overcurrent protection module [3 ].

A direct current power supply protection method comprises the following steps:

1) connecting a direct-current power supply protection device between a direct-current stabilized power supply [10] and electric equipment [11] in series;

2) the direct current power supply module [5] is started to provide working power supply for the overcurrent protection module [3], the direct current stabilized power supply [10] outputs direct current voltage, if the direct current stabilized power supply [10] and the electric equipment [11] are correctly connected, the positive polarity power supply indicator lamp [8] is on, and the reverse polarity power supply indicator lamp [7] is off, otherwise, the opposite is performed;

3) under the condition of correct wiring, a positive polarity power supply indicator lamp [8] is lightened, a power supply control switch [4] is manually switched on, the power supply voltage of a direct current stabilized power supply [10] enters a coil of a relay [1] through the power supply control switch [4], an overcurrent protection module [3] and a reverse diode [2] and forms a loop with the output negative terminal of the direct current stabilized power supply [10], at the moment, the coil of the relay [1] normally works, two contacts are attracted, the power supply indicator lamp [6] is lightened, the direct current stabilized power supply [10] normally supplies power to electric equipment [11], the overcurrent protection module [3] synchronously monitors the load of the electric equipment [11] in real time and carries out protection judgment, if the current exceeds a preset overcurrent protection value, a coil working power supply of the relay [1] is cut off through an internal relay, at the moment, a transient suppression diode [9] can quickly absorb sudden change inductive current generated by the coil of the relay [1] due to switch disconnection, reducing the impact on the system.

4) Under the condition of wrong wiring, a reverse polarity power supply indicator lamp [7] is lightened, a power supply control switch [4] is manually switched on, a power supply positive end of a direct current stabilized power supply [10] is connected to a coil negative end of a relay [1] and a positive end of a transient suppression diode [9] through a power supply negative line and then is connected to a negative end of a reverse diode [2], due to the reverse cut-off characteristic of the reverse diode [2], a power supply loop cannot be formed by the coil of the relay [1] at the moment, two contacts are in a disconnected state, the power supply indicator lamp [6] cannot be lightened, and an electric device [11] cannot be connected with reverse polarity voltage to play a role in reverse polarity power supply protection.

The invention has the beneficial effects that: the protection device can be used for selecting the specification of a corresponding device according to the load characteristic of electric equipment, can be flexibly embedded into a power supply circuit or power supply equipment with a direct-current power supply requirement, realizes reverse polarity protection and overload protection on a direct-current stabilized power supply, power supply control equipment, the electric equipment and a power supply line, is successfully used in various related equipment with a direct-current power supply control function, and can improve the reliability, safety and working efficiency of a power supply system; and the cost is low, and the method can be popularized and applied to most automatic test systems.

Drawings

Fig. 1 is a schematic diagram of a dc power supply protection device.

Detailed Description

The connection structure of the present invention will be described in detail with reference to the accompanying drawings and examples.

As shown in fig. 1, the dc power supply protection device of the present invention is composed of a relay [1], a backward diode [2], an overcurrent protection module [3], a power supply control switch [4], a dc power supply module [5], a power supply indicator lamp [6], a reverse polarity power supply indicator lamp [7], a positive polarity power supply indicator lamp [8] and a transient suppression diode [9 ]. The device can ensure the correct and safe power supply for the electric equipment [11] only by connecting a direct current stabilized voltage power supply [10 ].

Component 1: the relay adopts a double-circuit relay, such as DPST or DPDT type, and the working voltage and the load carrying capacity of the relay are selected according to the electric equipment;

component 2: the reverse diode adopts a reverse isolation type switch diode, has the functions of forward conduction and reverse cut-off, and selects the working voltage and the reverse breakdown voltage according to the working characteristics of the relay [1] and the system power supply voltage;

component 3: the overcurrent protection module is composed of a current sensor, a relay and an acquisition driving circuit, a Hall current sensor is used for detecting working current, a current limiting value can be preset, when actual current is larger than a preset current value, a switch signal is changed from low level to high level, the relay can be driven to switch, and an LED indicating lamp is used for indicating;

component 4: the power supply control switch is used for manually controlling power supply and carrying out model selection according to the working characteristics of the coil of the relay [1 ];

component 5: the direct current power supply module provides working voltage for the overcurrent protection module [3], and the voltage range of the direct current power supply module depends on the electricity utilization characteristics of the overcurrent protection module [3 ];

component 6: the power supply indicator lamp adopts a unipolar indicator lamp and is used for indicating the power supply state of the electric equipment;

component 7: the reverse polarity power supply indicator lamp adopts a single polarity indicator lamp and is used for indicating the polarity state of the power supply wiring of the accessed direct current stabilized voltage power supply [10 ];

component 8: the positive power supply indicator lamp adopts a single-polarity indicator lamp and is used for indicating the power supply wiring polarity state of the accessed direct current stabilized voltage power supply [10 ];

component 9: the transient suppression diode adopts a diode with high switching response speed, such as a Schottky diode, the unidirectional conductivity of the diode is formed by the contact of metal and a semiconductor, the switching speed is high, and the coil reversely connected in parallel with the relay [1] can quickly and effectively prevent the sudden change of inductive current at the moment of switching off the switch, thereby reducing the influence on the system.

The working principle of the direct current power supply protection device is as follows:

1) connecting a direct-current power supply protection device between a direct-current stabilized power supply [10] and electric equipment [11] in series;

2) the direct current power supply module [5] is started to provide working power supply for the overcurrent protection module [3], the direct current stabilized power supply [10] outputs direct current voltage, if the direct current stabilized power supply [10] and the electric equipment [11] are correctly connected, the positive polarity power supply indicator lamp [8] is on, and the reverse polarity power supply indicator lamp [7] is off, otherwise, the opposite is performed;

3) under the condition of correct wiring, a positive polarity power supply indicator lamp [8] is lightened, a power supply control switch [4] is manually switched on, the power supply voltage of a direct current stabilized power supply [10] enters a coil of a relay [1] through the power supply control switch [4], an overcurrent protection module [3] and a reverse diode [2] and forms a loop with the output negative terminal of the direct current stabilized power supply [10], at the moment, the coil of the relay [1] normally works, two contacts are attracted, the power supply indicator lamp [6] is lightened, the direct current stabilized power supply [10] normally supplies power to electric equipment [11], the overcurrent protection module [3] synchronously monitors the load of the electric equipment [11] in real time and carries out protection judgment, if the current exceeds a preset overcurrent protection value, a coil working power supply of the relay [1] is cut off through an internal relay, at the moment, a transient suppression diode [9] can quickly absorb sudden change inductive current generated by the coil of the relay [1] due to switch disconnection, reducing the impact on the system.

4) Under the condition of wrong wiring, a reverse polarity power supply indicator lamp [7] is lightened, a power supply control switch [4] is manually switched on, a power supply positive end of a direct current stabilized power supply [10] is connected to a coil negative end of a relay [1] and a positive end of a transient suppression diode [9] through a power supply negative line and then is connected to a negative end of a reverse diode [2], due to the reverse cut-off characteristic of the reverse diode [2], a power supply loop cannot be formed by the coil of the relay [1] at the moment, two contacts are in a disconnected state, the power supply indicator lamp [6] cannot be lightened, and an electric device [11] cannot be connected with reverse polarity voltage to play a role in reverse polarity power supply protection.