CN200990518Y - Buffer circuit of accumulator pile charging and discharging - Google Patents

Abstract

The utility model relates to an isolation circuit for charging and discharging a battery pack, which includes multiple groups of the same isolation circuit, which are multiple groups of single bridges composed of charging diodes and discharging diodes, and the anodes of the charging diodes of each group of single bridges are connected to the charger. The positive terminal of the output, the cathode of the discharge diode of each group of single bridges is connected to the input terminal of the inverter, the middle pole of each group of single bridges is respectively connected to the positive pole of each group of batteries, the negative poles of each group of batteries are connected in parallel, and connected to the charger respectively The negative input terminal of the inverter and the output terminal of the inverter; the main power supply is connected to the charger to charge the battery pack evenly through the charging diode, and the inverter converts the electric energy of the battery into alternating current to supply the load. Because the utility model adopts the charging and discharging isolation circuit, the charger can charge each group of batteries in a balanced manner, and discharge according to the specific voltage value of each group of batteries when discharging, so that each group of batteries will not be overcharged or overdischarged, and the battery group There will be no circulation between them, which can protect the battery to the greatest extent.

Description

Isolation circuit for battery charging and discharging

technical field

The utility model belongs to the field of power supply devices utilizing storage batteries for energy storage, and relates to an isolation circuit for charging and discharging storage battery packs, which is suitable for a power supply device for parallel charging and discharging of multiple sets of storage battery packs.

Background technique

At present, the demand and capacity of domestic power supply devices are increasing, which requires more and more batteries with the same capacity; if a large number of batteries are used in series, the voltage is very high (the voltage of a single battery for emergency power supply is generally 12V) ; Excessive voltage can not help but require the voltage level of the IGBT power tube to be increased, which doubles the hardware cost, and more attention should be paid to safety issues during operation, debugging, and maintenance. Therefore, when there are a large number of batteries, they should be connected in parallel to charge and discharge multiple groups of batteries. However, due to the slightly different internal resistance and performance of the batteries, unreasonable design may cause circulation between the battery groups or the Unbalanced charging and discharging, overcharging or over-discharging of a single battery pack will cause battery performance degradation or damage.

Contents of the invention

The problem to be solved by the utility model is to overcome the deficiencies of the prior art and provide an isolation circuit for charging and discharging of storage batteries. A charging and discharging isolation circuit is added to the positive connection of each group of storage batteries, and the charger provides a charge and discharge isolation circuit for each group. Battery equalization charge.

The utility model solves its technical problem and realizes by taking the following technical solutions:

According to the utility model, an isolation circuit for charging and discharging a storage battery pack includes multiple groups of the same isolation circuit, which are multiple groups of single bridges composed of charging diodes and discharging diodes, and the anodes of the charging diodes of each group of single bridges are connected to charge The positive output terminal of the inverter; the cathode of the discharge diode of each group of single bridges is connected to the input terminal of the inverter, the middle pole of each group of single bridges is respectively connected to the positive poles of each group of batteries, and the negative poles of each group of batteries are connected in parallel and connected separately The input negative terminal of the charger and the output terminal of the inverter; the main power supply is connected to the charger to charge the battery pack evenly through the charging diode, and the inverter converts the electric energy of the battery into alternating current to supply the load.

The utility model solves its technical problem and is to take the following technical solutions to further realize:

Two of the above-mentioned sets of identical isolation circuits are first connected to the charger by the main power supply to provide energy for the charger; the positive output terminal + D1 of the charger is respectively connected to the anodes of the charging diodes V1 and V3, The charging diode V1 and the discharging diode V2 form a single bridge, and the charging diode V3 and the discharging diode V4 form a single bridge; the cathodes of the charging diode V1 and the charging diode V3 are respectively connected to the positive poles of the battery packs DE1 and DE2, and are respectively connected to The anodes of the discharge diodes V2 and V4; the negative poles of the storage battery are connected to each other, and respectively connected to the input negative terminal N of the charger and the output terminal of the inverter; the cathodes of the discharge diode V2 and the discharge diode V4 are connected to the input terminal of the inverter , discharge the energy of the battery through the inverter.

Compared with the prior art, the utility model has obvious advantages and beneficial effects.

The utility model adopts a charging and discharging isolation circuit at the positive connection of each group of batteries, and uses the single-phase conductivity of the diode to make the charger charge each group of batteries in a balanced manner, and discharge according to the specific voltage value of each group of batteries when discharging. , each group of batteries will not be overcharged or overdischarged, and there will be no circulation between the battery groups, which protects the batteries to the greatest extent.

The specific embodiment of the utility model is given in detail by the following examples and accompanying drawings.

Description of drawings

Fig. 1 circuit principle block diagram of the utility model;

Fig. 2 is the schematic circuit diagram of the utility model.

Detailed ways

Below in conjunction with the accompanying drawings, the specific implementation, structure, features and effects provided by the present utility model will be described in detail as follows.

Referring to Figures 1-2, an isolation circuit for charging and discharging a battery pack includes multiple sets of identical isolation circuits, which are multiple sets of single bridges composed of charging diodes and discharging diodes, and the anodes of the charging diodes of each single bridge are connected to charge The positive output terminal of the inverter; the cathode of the discharge diode of each group of single bridges is connected to the input terminal of the inverter, the middle pole of each group of single bridges is respectively connected to the positive poles of each group of batteries, and the negative poles of each group of batteries are connected in parallel and connected separately The input negative terminal of the charger and the output terminal of the inverter; the main power supply is connected to the charger to charge the battery pack evenly through the charging diode, and the inverter converts the electric energy of the battery into alternating current to supply the load.

According to the size of the capacity, multiple sets of batteries with the same capacity and voltage can be connected in parallel, so there are also multiple sets of isolation circuits. Take the battery charge and discharge isolation circuit with two sets of batteries connected in parallel as an example: firstly, the main power supply is connected to the charging The charger provides energy for the charger; the positive output terminal + D1 of the charger is connected to the anodes of the charging diodes V1 and V3 respectively, the charging diode V1 and the discharging diode V2 form a single bridge, and the charging diode V3 and the discharging diode V4 form a single bridge Single bridge; the cathodes of the charging diode V1 and the charging diode V3 are respectively connected to the positive poles of the battery pack DE1, DE2, and are respectively connected to the anodes of the discharge diodes V2, V4; the negative poles of the battery are connected to each other, and are connected to the input negative terminal of the charger -N and the output terminal of the inverter; the cathodes of the discharge diode V2 and the discharge diode V4 are connected to the input terminal of the inverter, and the energy of the storage battery is released through inversion.

Working principle: When the grid has main power, it provides energy for the charger. The charger charges the battery pack +DE1 and +DE2 through two sets of charging isolation diodes, because the anodes of the charging diodes V1 and V3 are connected to the output positive bus of the same charger + D1, if there is a group of battery packs with a high voltage value, and the voltage of the +D1 bus determines the voltage of the lower battery pack, which is the sum of the voltage of the battery pack +DE and the voltage drop of the diode tube, using the characteristics of single-phase conduction of the diode , the anode voltage is higher than the cathode, the diode conducts, the charger charges the battery pack, and the anode voltage of the higher voltage battery pack is lower than the cathode voltage or the higher voltage value is less than the forward conduction voltage value of the diode, at this time the diode In the cut-off state, the charger cannot charge the battery pack, and the higher voltage battery pack is reversely isolated by the charging isolation diode V1, V3, and there is no circulation phenomenon that the higher voltage battery pack reverse charges the lower battery pack , to ensure the normal operation of the battery pack.

When there is no main power, the energy stored in the battery pack will be converted into three-phase alternating current through the inverter and released to the load. At this time, if the total voltage of each group of batteries is different, the group with higher voltage will be turned on through the discharge diode, and the electric energy of the battery group will be released to the busbar, which will be supplied to the load through inverter; the voltage of point |+E of the discharge busbar is higher than The voltage of the lower battery pack makes the discharge diode of the lower voltage pack reversely cut off, and there will be no phenomenon that the higher voltage battery pack charges the lower battery pack; only when the voltage of the higher battery pack is equal to the lower battery pack When the voltage value of the battery group is lower, the two groups of batteries are discharged at the same time; therefore, the two groups of batteries are guaranteed to be discharged in a balanced manner, and each group of batteries will not be over-discharged. Since there is no main power at this time, the output voltage of the charger is 0V, which is lower than the voltage value of the battery pack, so that the charging diodes V1 and V3 are in the reverse cut-off state, and the battery pack will not feed back electric energy to the charger.

Claims (2)

1. the buffer circuit of batteries charge and discharge, comprise the identical buffer circuit of many groups, it is characterized in that: the identical buffer circuit of described many groups is single bridge that many groups are made up of charging diode and discharge diode, and the anode of the charging diode of every group of single bridge connects the output plus terminal of charger; The negative electrode of the discharge diode of every group of single bridge connects the input of inverter, and the interpole of every group of single bridge connects the positive pole of every group storage battery respectively, and the negative pole of every group storage battery is connected in parallel, and connects the input negative terminal of charger and the output of inverter respectively; Main power supply connects charger through the equalizing charge of charging diode accumulators group, and inverter is reverse into alternating current with the electric energy of storage battery, supply load.

2. the buffer circuit of batteries charge and discharge according to claim 1 is characterized in that: wherein two groups of buffer circuits of the buffer circuit that described many groups are identical at first are connected to charger by main power supply, for charger provides energy; The output plus terminal of charger (+D1) being connected respectively to the anode of charging diode (V1, V3), charging diode (V1) is formed a single bridge with discharge diode (V2), and charging diode (V3) is formed a single bridge with discharge diode (V4); The negative electrode of charging diode (V1) and charging diode (V3) links to each other with the positive pole of batteries (DE1, DE2) respectively, is connected respectively to the anode of discharge diode (V2, V4) simultaneously; The negative pole of storage battery is connected to each other, and the input negative terminal that connects charger respectively (N) and the output of inverter; The negative electrode of discharge diode (V2) and discharge diode (V4) is connected to the input of inverter, bleeds off by the energy of inversion with storage battery.

Images