CN201789276U - Rectifier charging equipment protection circuit - Google Patents

Abstract

A protection circuit of a rectifying charging device comprises a rectifier, a filter capacitor, a storage battery, a first capacitor and a second capacitor, wherein the rectifier receives electric power of an external power supply and outputs rectifying voltage for power supply on an output side; a polarity protection element connected to one side of the filter capacitor for providing a bypass effect to the storage battery with reversed polarity to prevent the filter capacitor from being reversely charged by the storage battery; the anti-reflux device is connected between the filter capacitor and the storage battery in series, and can isolate the filter capacitor from the storage battery to avoid short-circuit accidents when the filter capacitor has abnormal faults; the overvoltage monitoring device can monitor the voltage at the output side of the rectifier, and when the monitoring voltage is too high and can damage peripheral equipment and the storage battery, the power-off switch on the external power supply and the power-off switch at the output side of the rectifier are controlled to form a non-conducting state, so that the power for the load is supplied by the storage battery.

Description

Rectifier charging equipment protection circuit

technical field

The utility model relates to a protection circuit for rectification and charging equipment, in particular to a circuit for protecting a filter capacitor and a storage battery of the rectification and charging equipment.

Background technique

Aiming at the problem that the power supply system cannot guarantee the quality of an uninterrupted power supply, users are generally accustomed to setting up backup battery packs for important emergency power consumption such as factory electrical switchboards, communication rooms, petrochemical or nuclear energy, and high-tech processes. However, users often mistakenly believe that after an additional battery pack is installed, the load will no longer have the worry of power failure. However, after years of abnormal cases, another potential problem has been revealed, that is, the operation reliability and reliability of the power supply equipment itself. Human error is often overlooked.

Please refer to Fig. 1, the rectification and charging equipment 1 of the common uninterruptible power supply system, the power semiconductor switch or the drive circuit in the rectification equipment 11 is out of control, so that the output voltage of the rectification equipment 11 is abnormally high, which may damage the battery 12 and load 13 side equipment, such as production line downtime, user communication network outage, extra maintenance costs will be added and the safety of electricity itself will be endangered; if capacitor 14 leaks and insulation deterioration occurs during system operation, there is no isolation battery 12 The power reverse flow device will cause the power to reverse flow to the capacitor 14 and cause a short circuit accident, which may cause a power outage on the load 13 side, and in the installation of a new battery 12 and the wiring construction of the battery 12, the poles of the battery 12 and the capacitor 14 are often caused by human factors. Sexual reverse connection causes damage to the capacitor 14, and the lack of perfect protection measures for the battery 12 and the capacitor 14 causes damage to many devices inside the uninterruptible power supply system and causes huge losses, and also endangers the electrical equipment output by the load 13 side.

Utility model content

The protection circuit of the rectification and charging equipment of the utility model overcomes the problem that the existing rectification and charging system does not have a circuit for perfect protection of the filter capacitor and the storage battery, which easily causes damage to the filter capacitor and the storage battery.

The technical scheme that the utility model solves the problems of the technologies described above is as follows:

Provide an overvoltage monitoring device that monitors the voltage on the output side of the rectifier. When it is detected that the voltage is too high to damage peripheral equipment, the overvoltage monitoring device can control the power-off switch on the external power supply and the power-off switch on the output side of the rectifier. The electric switch forms a non-conducting state, allowing the load to be supplied by the battery to avoid damage to the battery and the load electrical equipment due to overvoltage. As long as one of the power-off switches is not conducting, the effect of isolating the overvoltage can be achieved; one pole The polarity protection element is connected to one side of the filter capacitor, which can avoid damage to the filter capacitor due to human negligence and mistakenly connecting the battery with the reverse polarity of the filter capacitor. The polarity protection element can provide a bypass effect for the battery with reverse polarity. Prevent the filter capacitor from being reversely charged by the battery; an anti-backflow device is installed in series between the filter capacitor and the battery, which can be composed of multiple diodes connected in parallel to avoid power failure of the output load caused by a single fault open circuit. The anti-backflow device can protect the filter when the rectifier is not powered on. When the capacitor has no voltage, it can avoid short-circuit accidents caused by the wrong power supply of the battery to the filter capacitor, and if the filter capacitor has insulation deterioration or leakage during operation, it can also isolate the battery from returning to the filter capacitor, so that the load can be continuously powered and protected. The function of the battery.

The utility model mentioned above is for the stability of the rectification and charging equipment and the safety of power consumption itself, and the mechanism for protecting the storage battery and filter capacitor, which can reduce the damage caused by the failure of the rectification and charging equipment and human negligence, and improve the reliability of the power supply of the rectification and charging equipment. Spend.

From the above description, the utility model has the following beneficial effects:

1. The overvoltage monitoring device can effectively prevent overvoltage damage to load peripheral equipment and batteries, and greatly improve the safety of batteries and rectifying and charging equipment.

2. The polarity protection element of the filter capacitor can avoid human negligence, which may cause damage to the filter capacitor by the battery.

3. The anti-backflow device can prevent the battery from causing short-circuit accidents caused by the discharge of the battery to the filter capacitor when the rectifier circuit is not turned on, and the deterioration or leakage of the filter capacitor during operation, and isolate the filter capacitor from the battery to avoid short-circuit accidents.

Description of drawings

Fig. 1 is the structural diagram of the rectifying and charging equipment of the existing uninterruptible power supply system;

Fig. 2 is the structural diagram of the protection circuit of the rectifying and charging equipment of the present invention;

Fig. 3 is a circuit diagram of the protection circuit of the rectifying and charging equipment of the present invention.

Detailed ways

Please refer to Fig. 2, the protection circuit of rectifying and charging equipment of the present invention includes a rectifier 2, a filter capacitor 3, a storage battery 4, a polarity protection element 5, an anti-backflow device 6 and an overvoltage monitoring device 7, wherein :

Please refer to FIG. 3 , a rectifier 2 receives power from an external power source 9 and outputs a rectified voltage at the output side 21 for power supply.

A filter capacitor 3 is connected to the output side 21 of the rectifier 2 for filtering and charging.

A storage battery 4 is connected to the output side 21 of the rectifier 2 , and is output in parallel with the filter capacitor 3 at the output position of the filter capacitor 3 .

A polarity protection element 5 is connected to one side of the filter capacitor 3 , and the polarity protection element 5 can be a diode.

An anti-backflow device 6 is arranged in series between the filter capacitor 3 and the battery 4. The anti-backflow device 6 can be composed of a plurality of diodes connected in parallel or a plurality of unidirectional conduction thyristors connected in parallel, which can avoid a single fault open circuit and cause the output load 8 to be powered off. .

An overvoltage monitoring device 7 is connected to the output side 21 of the rectifier 2 to monitor the voltage of the output side 21 to control the power-off switch 71 on the external power supply 9 and the power-off switch 71 between the rectifier 2 and the battery 4 .

Please refer to Fig. 2 and Fig. 3, the operation process of the utility model is rectified by the rectifier 2 receiving the external power source 9, the rectified voltage is supplied by the output side 21 of the rectifier 2, and the power is stored in the battery 4 through the filter capacitor 3, and the load is supplied 8 electricity. However, the rectifier 2 may produce an abnormally high voltage on the output side 21 due to its own control failure, which may damage the electrical equipment of the battery 4 and the load 8. The overvoltage monitoring device 7 monitors that the voltage on the output side 21 is too high, that is, controls the external The power-off switch 71 on the power supply 9 and the power-off switch 71 on the output side 21 form a non-conductive state, allowing the load 8 to transfer electricity to be supplied by the battery 4, so as to avoid damage to the battery 4 and the load 8 electrical equipment due to overvoltage. As long as one of the cut-off switches 71 is not conducting, the effect of isolating overvoltage can be achieved. The polarity protection element 5 of the utility model can avoid damage to the filter capacitor 3 caused by the reverse connection of the battery 4 and the filter capacitor 3 due to human negligence, and the polarity protection element 5 can provide a bypass for the battery 4 with the reverse polarity The effect is to prevent the filter capacitor 3 from being reversely charged by the battery 4, which is a protection mechanism for the filter capacitor 3; if the filter capacitor 3 undergoes insulation degradation or leakage during operation, a short circuit accident will occur, so that the fuse 41 and the external power supply of the battery 4 can be protected. The fuse 91 of 9 fuses, causing the load 8 to lose power and damage the battery 4. However, the anti-backflow device 6 provided between the filter capacitor 3 and the battery 4 in this utility model can isolate the battery 4 from returning to the filter capacitor 3, so that the load 8 The power consumption is continuous and has the function of protecting the storage battery 4; when the rectifier 2 of the present invention is not turned on, the filter capacitor 3 is in a voltage-free state, and the anti-backflow device 6 can prevent the battery 4 from wrongly feeding the filter capacitor 3 to cause a short-circuit accident , can avoid the fuse 41 fuse of battery 4 and the damage of battery 4.

In summary, the polarity protection element 5, the anti-backflow device 6 and the overvoltage monitoring device 7 are all for the stability of the power supply of the rectification and charging equipment and the protection of the battery 4 and the filter capacitor 3, which can reduce the damage caused by human negligence on the rectification and charging equipment. Equipment damage caused, and improve the power supply reliability of rectification and charging equipment.

Claims (12)

1. A protection circuit for rectifying and charging equipment, comprising: a rectifier (2), which accepts the power of an external power supply (9), and outputs a rectified voltage at the output side (21); a filter capacitor (3), connected to the rectifier ( 2) on the output side (21); a storage battery (4), connected to the output side (21) of the rectifier (2), is arranged in parallel with the filter capacitor (3) at the output position of the filter capacitor (3), and is characterized in that : It also includes a polarity protection element (5) connected to one side of the filter capacitor (3); an anti-backflow device (6), which is arranged in series between the filter capacitor (3) and the storage battery (4); A voltage monitoring device (7), connected to the output side (21) of the rectifier (2) to monitor the voltage of the output side (21), to control the power-off switch (71) located on the external power supply (9), and the rectifier ( 2) The cut-off switch (71) between battery (4). 2. The protection circuit for rectifying and charging equipment according to claim 1, characterized in that: the anti-backflow device (6) is composed of a plurality of diodes connected in parallel. 3. The protection circuit for rectifying and charging equipment according to claim 1, characterized in that: the anti-backflow device (6) is composed of a plurality of unidirectional conduction thyristors connected in parallel. 4. A protection circuit for rectifying and charging equipment, comprising: a rectifier (2), which receives the power of an external power supply (9), and outputs a rectified voltage at the output side (21); a filter capacitor (3), connected to the rectifier ( 2) on the output side (21); a storage battery (4), connected to the output side (21) of the rectifier (2), is arranged in parallel with the filter capacitor (3) at the output position of the filter capacitor (3), and is characterized in that : It also includes an anti-backflow device (6), which is arranged in series between the filter capacitor (3) and the storage battery (4); and an overvoltage monitoring device (7), which is connected to the output side (21) of the rectifier (2) to The voltage of the output side (21) is monitored to control the power-off switch (71) arranged on the external power supply (9) and the power-off switch (71) between the rectifier (2) and the storage battery (4). 5. The protection circuit for rectifying and charging equipment according to claim 4, characterized in that: one side of the filter capacitor (3) is also connected with a polarity protection element (5), which can prevent the filter capacitor (3) from being damaged by the battery ( 4) Reverse polarity charging. 6. The protection circuit for rectifying and charging equipment according to claim 4, characterized in that: the anti-backflow device (6) is composed of a plurality of diodes connected in parallel. 7. The protection circuit for rectifying and charging equipment according to claim 4, characterized in that: the anti-backflow device (6) is composed of a plurality of unidirectional conduction thyristors connected in parallel. 8. A protection circuit for rectifying and charging equipment, comprising: a rectifier (2), which receives power from an external power supply (9), and outputs a rectified voltage at the output side (21); a filter capacitor (3), connected to the rectifier ( 2) on the output side (21); a storage battery (4), connected to the output side (21) of the rectifier (2), is arranged in parallel with the filter capacitor (3) at the output position of the filter capacitor (3), and is characterized in that : also includes an overvoltage monitoring device (7), connected to the output side (21) of the rectifier (2) to monitor the voltage of the output side (21), to control the power-off switch (71) on the external power supply (9) ), and the power-off switch (71) between the rectifier (2) and the storage battery (4). 9. The rectifying and charging equipment protection circuit according to claim 8, characterized in that: one side of the filter capacitor (3) is also connected with a polarity protection element (5), which can prevent the filter capacitor (3) from being damaged by the battery ( 4) Reverse polarity charging. 10. The protection circuit for rectifying and charging equipment according to claim 8, characterized in that an anti-backflow device (6) is connected in series between the filter capacitor (3) and the storage battery (4). 11. The protection circuit for rectifying and charging equipment according to claim 10, characterized in that: the anti-backflow device (6) is composed of a plurality of diodes connected in parallel. 12. The protection circuit for rectifying and charging equipment according to claim 10, characterized in that: the anti-backflow device (6) is composed of a plurality of unidirectional conduction thyristors connected in parallel.

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