KR20210019841A - solar battery charge-discharge control device - Google Patents

Abstract

Provided is a battery charging and discharging control device using solar power generation which can control each battery to operate in a charging mode or a discharging mode. The battery charging and discharging control device using solar power generation comprises: a multi-charging and discharging control unit detecting a voltage of each of a plurality of batteries in real time and controlling each battery to operate in a charging mode or a discharging mode based on a discharging completion voltage and a full charging voltage; and an inverter selectively transferring charging power transmitted from both solar panels to the plurality of batteries under control of the multi-charging and discharging control unit.

Description

Battery charge-discharge control device using solar power generation

The present invention relates to a battery charging technology, and more particularly, to a battery charging and discharging control apparatus using solar power.

The lead acid battery market is expected to continue to grow as batteries composed of lead acid batteries are used in hybrid vehicles, which are the center of next-generation green growth, and lead acid batteries for power storage are used in the solar and wind power industries as well as in the Smart Grid business. .

With the expansion of the battery composed of lead acid batteries, that is, the secondary battery market, domestic and foreign companies are developing technologies and products related to the battery management system (BMS: Battery Management System) installed in solar energy storage devices, including electric vehicles, electric scooters, etc. It is being done actively.

After 2-3 years of normal use, the duration of use of the battery is reduced to less than half, and the battery used for 5 hours on a single charge must be charged every 2 hours, and the battery with reduced usage time is eventually disposed of. do.

A battery made of a lead acid battery has the advantage of maintaining a stable voltage output, but the battery life is drastically shortened when overcharging/overdischarging. In particular, if the over-discharge condition continues, it is fatal to the battery life.

In particular, since the life of the battery may be shortened depending on the stability of the power supplied from the inverter, there is a need for a technology capable of stably controlling the DC power supply for charging supplied from the battery inverter.

A general battery charging device performs charging and discharging by connecting a plurality of battery packs in parallel.

Therefore, when charging multiple batteries at the same time, the charging current must be high, and when charging with a constant current, the charging time takes a lot of time to complete charging.

In particular, since it takes a long time to fully charge a plurality of batteries that have undergone over-discharge, the waiting time until power can be supplied to the battery after charging is long, and thus the power of the battery may not be used for a long time. In the case of overdischarge, not only the time to full charge is lengthened, but also the cycle of the entire battery is shortened, so that the replacement cycle can be shortened.

In addition, in the series-type charging method, charging and discharging are separated, so charging and discharging cannot be simultaneously performed. That is, after charging is completed, the switch is operated to discharge, and it is not possible to individually charge and discharge by selecting some batteries.

The present invention has been proposed to solve the above technical problem, and detects the voltage of each of a plurality of batteries in real time, and controls each battery to operate in a charging mode or a discharging mode based on the discharge completion voltage and the full charge voltage. It provides a battery charge/discharge control device using solar power generation.

According to an embodiment of the present invention, a multi-charge/discharge controller configured to detect voltages of a plurality of batteries in real time and control each battery to operate in a charge mode or a discharge mode based on a discharge completion voltage and a full charge voltage; And an inverter selectively transferring charging power transmitted from the solar panel to the plurality of batteries according to the control of the multi charging/discharging controller.

In addition, the multi-charge/discharge control unit may rapidly charge only one selected battery from among the plurality of batteries in the priority charging mode, and electrical connection with the plurality of batteries after a predetermined period of time from the point in time when use of all batteries is stopped. It is characterized in that the standby power consumption is reduced by blocking by, charging at least one or more batteries that are less than or equal to the discharge completion voltage among the plurality of batteries, and converting at least one battery that has reached the full charge voltage into a discharge standby state. .

A battery charge/discharge control device using solar power according to an embodiment of the present invention,

The voltages of each of the plurality of batteries are sensed in real time, and each battery can be controlled to operate in a charging mode or a discharging mode based on a discharge completion voltage and a full charge voltage. Accordingly, the use time of the battery can be prolonged, and operation continuity of a device operating using the power of the battery can be guaranteed.

1 is a configuration diagram of a battery charge/discharge control device 1 according to an embodiment of the present invention
2 is a detailed configuration diagram of the battery charge/discharge control device 1
3 is a first flow chart showing an operation process of the battery charge/discharge control device 1
4 is a second flow chart showing an operation process of the battery charge/discharge control device 1

Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings in order to describe in detail enough to allow those of ordinary skill in the art to easily implement the technical idea of the present invention.

1 is a block diagram of a battery charge/discharge control apparatus 1 according to an embodiment of the present invention.

The battery charge/discharge control device 1 according to the present embodiment includes only a simple configuration for clearly describing the technical idea to be proposed.

Referring to FIG. 1, the battery charge/discharge control device 1 includes a solar panel 10, an inverter 20, a multi charge/discharge control unit 30, and a plurality of batteries 40.

A detailed configuration and main operation of the battery charge/discharge control device 1 configured as described above are as follows.

The multi-charge/discharge controller 30 senses the voltages of each of the plurality of batteries 40 in real time, and controls each battery to operate in a charging mode or a discharging mode based on a discharge completion voltage and a full charge voltage.

The inverter 20 selectively transfers the charging power transmitted from the solar panel 10 to the plurality of batteries 40 under the control of the multi-charge/discharge controller 30.

The inverter 20 of the present invention converts a DC voltage to an AC voltage to supply driving power to a home or industrial electronic device and simultaneously supplies a DC voltage to a plurality of batteries 40.

The multi-charge/discharge control unit 30 rapidly charges only one battery selected from among the plurality of batteries 40 in the priority charging mode.

In addition, the multi-charge/discharge control unit 30 reduces standby power consumption by electrically disconnecting the connection with the plurality of batteries 40 after a predetermined period of time from when all the batteries are stopped.

In addition, the multi-charge/discharge control unit 30 performs a control operation of charging at least one or more batteries of the plurality of batteries 40 that are less than or equal to the discharge completion voltage, and switching at least one or more batteries that have reached the full charging voltage into a discharge standby state. Run.

Here, the discharge completion voltage (Low Battery Voltage, LBV) is defined as the reference voltage at which the battery should start charging, and the full charge voltage (High Battery Voltage, HBV) is completely charged and discharges (using battery power). Is defined as the voltage that is present.

2 is a detailed configuration diagram of the battery charge/discharge control device 1, FIG. 3 is a first flow chart showing an operation process of the battery charge/discharge control device 1, and FIG. 4 is a diagram of the battery charge/discharge control device 1 It is a second flow chart showing the operation process.

The operation process of the battery charge/discharge control device 1 will be described with reference to FIGS. 2 to 4.

The multi-charge/discharge control unit 30 of the battery charge/discharge control device 1 includes a voltage detection unit 31, a charge control signal generation unit 32, a battery selection unit 33, and a discharge selection unit 34. And, it is configured to include a charge and discharge control unit 35.

A plurality of battery packs 40 are used according to an increase in power use or capacity of a photovoltaic power generation facility. The configuration of the plurality of battery packs 40 is connected in series and in parallel.

A plurality of battery packs 40 are divided by channel to sequentially charge the plurality of battery packs 40 with one inverter 20, or alternatively, the entire battery pack 40 can be simultaneously charged in parallel. .

In addition, discharging is performed so that the battery pack, which has been charged up to the set voltage (HBV), proceeds with priority, so that a plurality of battery packs are not discharged at the same time and the channels of the battery pack are completely charged.

Only one channel of the separated plurality of battery pack channels is first discharged, and the remaining channels are converted to a standby state in which they can be discharged when charging or full charging is completed. In addition, when the discharging battery pack channel reaches the set voltage (LBV), it automatically switches to the charging mode, and at the same time, after charging is completed, it is switched to another channel in the discharge standby state so that discharging proceeds.

The voltage detection unit 31 can set the voltage at the time of overdischarge and overcharge-Low Battery Voltage (LBV) or High Battery Voltage (HBV) -. Create and deliver. The voltage sensing unit 31 displays a voltage, and enables it to be checked in case of overdischarge using a warning or a light emitting device (LED).

The charging control signal generation unit 32 outputs a control signal to sequentially control the charging progress of the plurality of batteries 40 according to the detection result of the voltage detection unit 31.

That is, when a signal indicating that the discharge completion voltage (LBV) has been reached is detected, charging starts in the channel part of the battery pack to be charged, and when charging is completed, a control signal to switch to a standby state so that it can be discharged. Prints. At this time, when the arrival signal of the discharge completion voltage (Low Battery Voltage, LBV) is sequentially detected, charging is performed at the same time, or a control signal is output to control charging sequentially for each channel.

The battery selection unit 33 is a switch unit capable of automatically/manually selecting charging and discharging of a plurality of battery pack channels, and may arbitrarily block charging and discharging when switching manually. This can be selected to prevent malfunction of the entire device or safely replace it by manually shutting off some channels of the battery pack when an abnormality occurs (eg battery life is complete). The battery selection unit 33 is automatically controlled by the voltage detection unit 31 and the charge control signal generation unit 32 in the automatic mode.

The discharge selector 34 controls each channel of the battery pack to be discharged for each channel while charging is completed. The battery pack channel in a fully charged state is in a standby state so that it can be discharged, and when the current discharged battery pack channel reaches the discharge completion voltage (Low Battery Voltage, LBV), the standby battery pack channel sequentially discharges. It is controlled so that it can proceed. That is, a battery in a standby state that is fully charged after being cut off by over-discharge is selected so that power can be continuously used. When switching to a charging state due to over-discharge, power consumption can be minimized with its own power saving mode.

The charge/discharge control unit 35 selectively transfers the power of the inverter 20 so that each battery can perform a charging or discharging operation, or performs a switching operation so that it can contact a specific node.

The battery charge/discharge control apparatus 1 of the present invention extends the charge/discharge cycle of the battery to achieve a reduction in replacement cost of a battery according to long-time use. In addition, maintenance and repair costs can be classified by each battery pack channel to determine the cost increase due to the overall replacement of the battery pack compared to the previous one and the occurrence of function offset due to the difference in capacity of the battery when partially replaced. The change in capacity due to deterioration in performance is also reduced, and the use period of the battery can be extended.

For reference, the inverter 20 may receive DC power stored in the solar panel 10 to generate DC power for charging, or receive AC power and switch to high frequency to generate DC power for charging.

When the inverter 20 is supplied with high voltage AC power, a varistor, a fuse, an electromagnetic noise filter, an overcurrent limiting circuit, and the like may be disposed at the input terminal.

In particular, since the transistors and diodes of the rectifier circuit emit a lot of heat, a heat sink can be attached. In addition, if the element of the rectifier circuit is overheated, the amount of current increases rapidly and the rectifier circuit may be damaged, so the maximum current value is limited based on the temperature value of the element included in the inverter 20, especially the element of the rectifier circuit. do.

That is, the inverter 20 adjusts the maximum amount of current that can be output based on the temperature value of the internal device in adjusting the maximum amount of current of the generated DC power supply for charging.

The inverter 20 controls to output the maximum amount of current (rated current) that can be generated when the temperature value of the internal device is less than the reference temperature, and responds to an increase in temperature when the temperature value of the internal device is higher than the reference temperature. The operation of gradually reducing the maximum amount of current that can be generated (rated current) can be performed.

Although not shown in the drawing, dummy battery cells may be arranged to check charging performance. The inverter 20 charges by supplying DC power for charging to the dummy battery cell in a debug mode or a monitoring mode. That is, while the dummy battery cell is being charged, the inverter 20 may detect a change amount of the DC power for charging and adjust the maximum amount of current of the DC power for charging according to whether the change amount exceeds the reference value.

That is, the inverter 20 can check the state of charge using the built-in dummy battery cell even when an external battery is not connected in the debug mode or the monitoring mode.

When charging the dummy battery cell, the inverter 20 controls to gradually increase the maximum amount of current, and at this time, it records the result while continuously monitoring the amount of change per hour of the DC power supply for charging (voltage, current).

If, when the amount of change is greater than the reference error value when the DC power supply for charging rises, the inverter 20 sets the amount of current immediately before exceeding the reference error value as the maximum amount of current.

For reference, the inverter 20 is set to limit the maximum amount of current only when the amount of change in the DC power supply for charging exceeds the reference error value 3 or more times while repeatedly charging/discharging the dummy battery cell at least 10 times. .

In addition, the inverter 20 divides the current rising section of the charging DC power into a plurality of sections, and then limits the maximum amount of current only when the amount of change of the DC power for charging exceeds the reference error value three or more times in the same section. It can also be set.

For example, after dividing into 0 ~ 1A rising section (1st section), 1 ~ 2A rising section (2nd section), 2 ~ 3A rising section (3rd section), 3 ~ 4A rising section (4th section) The amount of change in the DC power for charging can be monitored.If it is detected that the reference error value exceeds three or more times in the third section, the current amount of the second section is the maximum current amount of the DC power for charging when the actual battery is charged. Is set.

Meanwhile, the dummy battery cell may be configured to supply emergency power to the inverter 20 and the multi-charge/discharge control unit 30. That is, the power charged in the dummy battery cell may perform the function of the uninterruptible power supply.

For example, if the supply of external AC power is suddenly cut off due to a power failure or the like during the operation of charging the external battery, the dummy battery cell supplies emergency power to the inverter 20 and the multi-charge/discharge control unit 30 to save the external battery. After further charging for a predetermined period of time, it is possible to provide a power source capable of stably stopping the charging operation.

Since power from the dummy battery cells is continuously supplied to the inverter 20 and the multi-charge/discharge control unit 30, when external AC power is supplied again after a power failure, the inverter 20 and the multi-charge/discharge control unit 30 The charging operation can be quickly performed again in consideration of the previous charging state.

For reference, the inverter 20 and the multi-charge/discharge control unit 30 may further include an active noise control unit, which may occur in a state in which the battery is charged or in a standby state after charging. It is possible to perform an operation to cancel out the high-frequency audible noise.

That is, the active noise control unit detects whether noise corresponding to a preset audible frequency section (human audible frequency) is generated, and when noise occurs, generates a control sound that cancels sound waves in the region to block the noise.

A battery charge/discharge control device using solar power according to an embodiment of the present invention,

The voltages of each of the plurality of batteries are sensed in real time, and each battery can be controlled to operate in a charging mode or a discharging mode based on a discharge completion voltage and a full charge voltage. Accordingly, the use time of the battery can be prolonged, and operation continuity of a device operating using the power of the battery can be ensured.

As such, those skilled in the art to which the present invention pertains will be able to understand that the present invention can be implemented in other specific forms without changing the technical spirit or essential features thereof. Therefore, the embodiments described above are illustrative in all respects and should be understood as non-limiting. The scope of the present invention is indicated by the claims to be described later rather than the detailed description, and all changes or modified forms derived from the meaning and scope of the claims and their equivalent concepts should be interpreted as being included in the scope of the present invention. do.

10: solar panel
20: inverter
30: multi charge/discharge control unit
31: voltage detection unit
32: charge control signal generator
33: battery selection unit
34: discharge selector
35: charge/discharge control unit
40: multiple batteries

Claims (2)

A multi-charge/discharge controller configured to sense voltages of each of the plurality of batteries in real time and control each battery to operate in a charging mode or a discharging mode based on a discharge completion voltage and a full charge voltage; And
Battery charging/discharging control apparatus using solar power including an inverter for selectively transferring charging power transmitted from the solar panel to the plurality of batteries under control of the multi charging/discharging controller.
The method of claim 1,
The multi charge/discharge control unit,
In the priority charging mode, rapidly charging only one battery selected from among the plurality of batteries,
After a certain period of time from the time when all the batteries are stopped, the connection with the plurality of batteries is electrically cut off to reduce the consumption of standby power,
A battery charge/discharge control apparatus using photovoltaic power generation, characterized in that charging at least one or more batteries of the plurality of batteries having a discharge completion voltage or less, and converting at least one or more batteries having reached a full charge voltage into a discharge standby state.

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