CN111817370A - A battery protection circuit - Google Patents

Abstract

The invention relates to a storage battery protection circuit. The storage battery protection circuit comprises a resistor R1, a resistor R2, a resistor R3, a resistor R4, a voltage stabilizing diode DW1, a voltage stabilizing diode DW2, a triode T1, a triode T2 and a reverse protection diode D; the storage battery protection circuit is connected in parallel to each storage battery of the storage battery pack, the positive pole of the storage battery protection circuit is connected with the positive pole of the storage battery connected in parallel, and the negative pole of the storage battery protection circuit is connected with the negative pole of the storage battery connected in parallel. The storage battery protection circuit can prevent the storage battery from shortening the service life of the storage battery due to inconsistent health of the storage battery caused by inconsistent self-discharge of the storage battery; the storage battery can be prevented from being damaged due to overvoltage charging; the service life of the storage battery can be effectively prolonged, the battery faults of a power system, a power plant, a mobile station and a bank system UPS are reduced, and the reliability is improved.

Description

A battery protection circuit

technical field

The invention relates to the field of battery protection, in particular to the technical field of 48-220V low-voltage direct-current systems powered by uninterruptible power supplies of power systems, power plants, bank systems, and wireless stations using low-voltage direct-current battery packs.

Background technique

For 48-220V low-voltage DC systems powered by uninterruptible power supplies in power systems, power plants, and banking systems, the self-discharge of each battery in the battery pack is different during operation. Over time, some batteries will be overcharged, and some batteries will be undercharged. Charging, overcharging will damage the battery in advance.

After the battery is damaged, when the power system fails, the AC voltage fluctuates or disappears, and the protection, automatic devices, and circuit breakers will lose the DC power supply. , equipment damage and other malignant consequences.

In the banking system, after the battery is damaged, if the AC power supply disappears, it will cause data loss and cause a measurable economic loss.

In the wireless station, after the battery is damaged, if the AC power supply for power supply disappears, it will cause the loss of data and the interruption of mobile phone and network communication, which will bring immeasurable losses to people's lives and property.

To this end, it is necessary to find a device to eliminate the inconsistent self-discharge of the battery, or the inconsistent voltage of the battery replacement, and the battery is easily damaged.

SUMMARY OF THE INVENTION

In view of the above-mentioned problems, the present invention aims to solve the above-described problems. An object of the present invention is to provide a battery protection circuit that solves the above problems. Specifically, the present invention is a battery protection circuit with high reliability, which can prevent the battery from being damaged by over-voltage charging and effectively prolong the life of the battery.

The technical scheme of the present invention is: a battery protection circuit, comprising a resistor R1, a resistor R2, a resistor R3, a resistor R4, a Zener diode DW1, a Zener diode DW2, a transistor T1, a transistor T2, and a reverse protection diode D;

The first end of the resistor R1, the emitter of the transistor T1, the first end of the resistor R4, and the cathode of the diode D are connected together as the positive (+) pole of the battery protection circuit, the anode of the zener diode DW2, the transistor T2 The emitter of the diode D and the anode of the diode D are connected together as the negative (-) pole of the battery protection circuit; the second end of the resistor R1, the first end of the resistor R2, and the cathode of the Zener diode DW1 are connected together, and the Zener diode The anode of DW1 is connected with the cathode of the Zener diode DW2, the second end of the resistor R2 is connected with the base of the transistor T1, the collector of the transistor T1 is connected with the first end of the resistor R3, and the third end of the resistor R3 is connected together. The two terminals are connected to the base of the transistor T2, and the second terminal of the resistor R4 is connected to the collector of the transistor T2.

Further, the battery protection circuit is connected in parallel to each battery of the battery pack, the positive pole of the battery protection circuit is connected to the positive pole of the parallel battery, and the negative pole of the battery protection circuit is connected to the negative pole of the parallel battery.

The beneficial effects of the present invention are:

(1) The present invention can prevent the inconsistent battery health caused by the inconsistent self-discharge of the battery and shorten the life of the battery;

(2) It can prevent the battery from being damaged by over-voltage charging;

(3) After the batteries with the same health level and different voltages are replaced in a group, the capacity levels of all batteries can be automatically balanced at the same value;

(4) The device can effectively prolong the life of the battery, reduce the battery failure of the power system, power plant, mobile station, and bank system UPS, and improve reliability.

Other characteristic features and advantages of the present invention will become apparent upon reading the following description of exemplary embodiments with reference to the accompanying drawings.

Description of drawings

The accompanying drawings, which are incorporated in and constitute a part of the specification, illustrate embodiments of the invention and, together with the description, serve to explain the principles of the invention. In the figures, like reference numerals are used to refer to like elements. The drawings in the following description are some, but not all, embodiments of the invention. For those of ordinary skill in the art, other drawings can be obtained from these drawings without creative effort.

FIG. 1 exemplarily shows a schematic structural diagram of a battery protection circuit of the present invention;

FIG. 2 exemplarily shows a schematic structural diagram of the battery protection circuit of the present invention when applied.

Detailed ways

In order to make the purposes, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments These are some embodiments of the present invention, but not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention. It should be noted that, the embodiments in the present application and the features in the embodiments may be arbitrarily combined with each other if there is no conflict.

The battery protection circuit provided according to the present invention will be described in detail below with reference to the accompanying drawings.

Embodiment 1: As shown in FIG. 1, a battery protection circuit includes a resistor R1, a resistor R2, a resistor R3, a resistor R4, a Zener diode DW1, a Zener diode DW2, a transistor T1, a transistor T2, and a reverse protection diode D. ;

The first end of the resistor R1, the emitter of the transistor T1, the first end of the resistor R4, and the cathode of the diode D are connected together as the positive (+) pole of the battery protection circuit, the anode of the zener diode DW2, the transistor T2 The emitter of the diode D and the anode of the diode D are connected together as the negative (-) pole of the battery protection circuit; the second end of the resistor R1, the first end of the resistor R2, and the cathode of the Zener diode DW1 are connected together, and the Zener diode The anode of DW1 is connected with the cathode of the Zener diode DW2, the second end of the resistor R2 is connected with the base of the transistor T1, the collector of the transistor T1 is connected with the first end of the resistor R3, and the third end of the resistor R3 is connected together. The two terminals are connected to the base of the transistor T2, and the second terminal of the resistor R4 is connected to the collector of the transistor T2.

Further, the battery protection circuit is connected in parallel to each battery of the battery pack, the positive pole of the battery protection circuit is connected to the positive pole of the parallel battery, and the negative pole of the battery protection circuit is connected to the negative pole of the parallel battery.

The working principle of the present invention is:

When the present invention is used, it is connected in parallel with the storage battery. The present invention has two working voltages, 6V and 12V. This article takes the common 12V as an example.

In application, the positive (+) pole of the present invention is connected to the positive pole of the battery, the negative (-) pole is connected to the negative (-) pole of the battery, and each battery is connected in parallel with a circuit of the present invention as shown in FIG. 1 .

The voltage of the 12V battery during normal operation is between 13.0-13.4V, the combined voltage of DW1 and DW2 is selected to be 12.6V, and the V _be of the triode T1 is -0.6V. At this time, the voltage between the (+) and (-) poles of the module is When the voltage reaches 13.0V, the low-power triode T1 is turned on, the b-pole current I _b1 of the triode T1 is amplified by the T1 triode, and then supplied to the b-pole of the triode T2 through the resistor R3, and the c-pole current I _c1 of the triode T1 It is equal to the b-pole current I _b2 of the triode T2, and I _c1 is amplified by the triode T2 and then a larger current flows from its c-pole, thereby reducing the charging current of the battery. Due to the self-discharge of the battery, its The voltage between the (+) and (-) poles drops.

The higher the voltage between (+) and (-) of the present invention, the greater the current flowing in the module of the present invention, so that the levels between the batteries are automatically balanced, preventing the overcharge and undercharge of the batteries, effectively prolonging the It prolongs the service life of the battery pack and improves the safety and reliability of the operation of power systems, power plants, banking systems and mobile stations.

In the circuit, DW1 and DW2 are used in series, in order to obtain a zener diode close to our desired voltage through the combination of diodes of various voltages. The function of R1 is to provide a working current to the Zener diode, so that the voltage starting section of the Zener diode is more stable. The function of the resistor R2 is to prevent the PN junction between the b pole and the e pole of T1 from burning out when the voltage between (+) and (-) of the module of the present invention is too high, and the function of R3 is to prevent the C pole of the triode T1 from flowing through. Excessive current, the PN junction between the b pole and the e pole of the transistor T2 flows through an excessive current and burns out. Resistor R4 is to prevent the C pole of transistor T2 from being burned out due to excessive current flowing. The function of diode D is to prevent the module from burning out the module when its parallel battery is open. At the same time, when one battery is open, other batteries can continue to work, but the voltage of the entire battery is too low. Of course, at 6V (12V) ) In the 110V (220V) DC system composed of batteries, the open circuit of a single battery has little effect on the voltage of the entire battery group, and it can continue to work for a short time.

The above-described contents can be implemented individually or in various combinations, and these modifications are all within the protection scope of the present invention.

It should be noted that, in this document, relational terms such as first and second are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any relationship between these entities or operations. any such actual relationship or sequence exists. Moreover, the term "comprising" or any other variation thereof is intended to encompass a non-exclusive inclusion, whereby an article or device comprising a list of elements includes not only those elements, but also other elements not expressly listed, or else includes An element inherent to such an item or device. Without further limitation, an element defined by the phrase "comprising" does not preclude the presence of additional identical elements in the article or device comprising said element.

The above embodiments are only used to illustrate the technical solutions of the present invention and not to limit them, and the present invention is only described in detail with reference to the preferred embodiments. It should be understood by those of ordinary skill in the art that the technical solutions of the present invention can be modified or equivalently replaced without departing from the spirit and scope of the technical solutions of the present invention, and should be included in the scope of the claims of the present invention.

Claims (2)

1. a battery protection circuit, is characterized in that: comprise resistance R1, resistance R2, resistance R3, resistance R4, zener diode DW1, zener diode DW2, triode T1, triode T2, reverse protection diode D; The first end of the resistor R1, the emitter of the triode T1, the first end of the resistor R4, and the cathode of the diode D are connected together as the positive electrode of the battery protection circuit, the anode of the zener diode DW2, the emitter of the triode T2, The anodes of the diode D are connected together as the negative electrode of the battery protection circuit; the second end of the resistor R1, the first end of the resistor R2, and the cathode of the Zener diode DW1 are connected together, and the anode of the Zener diode DW1 is connected to the Zener diode DW2. The cathodes are connected together, the second end of the resistor R2 is connected with the base of the transistor T1, the collector of the transistor T1 is connected with the first end of the resistor R3, the second end of the resistor R3 is connected with the base of the transistor T2 Connected together, the second end of resistor R4 is connected to the collector of transistor T2. 2. The battery protection circuit according to claim 1, characterized in that: the battery protection circuit is connected in parallel to each battery of the battery pack, the positive pole of the battery protection circuit is connected to the positive pole of the parallel battery, and the The negative pole is connected to the negative pole of the battery connected in parallel.

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