KR102469243B1 - Electric vehicle charging system - Google Patents

Abstract

The present embodiments relate to an electric vehicle charging system. In one aspect, the present embodiments are an energy generating device that generates power from renewable energy, an energy storage device that stores or converts power supplied from the energy generating device, and stores converted power supplied from the energy storage device or supplies it to an electric vehicle. A cost function is calculated by obtaining information on factors for controlling a target voltage and a factor for controlling a target energy self-sufficiency rate from an electric vehicle charging device, an energy generating device, an energy storage device, and an electric vehicle charging device. An electric vehicle charging system including a control device controlling power of at least one of an energy generating device, an energy storage device, and an electric vehicle charging device based on a minimum value that a function may have may be provided.

Description

Electric vehicle charging system {ELECTRIC VEHICLE CHARGING SYSTEM}

The present embodiments relate to an electric vehicle charging system. Specifically, the present embodiments relate to an electric vehicle charging system capable of integrally controlling power of an energy generating device, an energy storage device, and an electric vehicle charging device.

An electric vehicle (EV) drives a motor with battery power, so it has fewer air pollutants such as exhaust gas and noise than conventional gasoline engine vehicles, has fewer breakdowns, longer lifespan, and simpler driving operation. there is

Due to these advantages of electric vehicles, the demand for electric vehicles is rapidly increasing recently, and since the problem of battery charging is the most important issue for electric vehicles, there is a need to build an electric vehicle charging infrastructure that can be easily charged anytime, anywhere.

However, indiscriminate installation of an electric vehicle charging system may adversely affect the power quality and stability of the existing power system, and the existing electric vehicle charging system has a problem in that facility expansion is required due to excess capacity.

In order to solve this problem, an electric vehicle charging system combining renewable energy and an energy storage device has recently been installed. However, since components such as an energy generating device, an energy storage device, and an electric vehicle charging device are individually controlled, it becomes a limitation in increasing the operating efficiency of the electric vehicle charging system. In addition, as power from the power system is continuously supplied even though the energy storage device and the electric vehicle charging device are in an abnormal state, a fire may occur, which poses a safety problem of the electric vehicle charging system.

The present embodiments may provide an electric vehicle charging system capable of integrally controlling power of an energy generating device, an energy storage device, and an electric vehicle charging device.

In addition, the present embodiments can provide an electric vehicle charging system capable of securing stability by separating a device in an abnormal state and a power system device.

In one aspect, the present embodiments are an energy generating device that generates power from renewable energy, an energy storage device that stores or converts power supplied from the energy generating device, and stores converted power supplied from the energy storage device or supplies it to an electric vehicle. A cost function is calculated by obtaining information on factors for controlling a target voltage and a factor for controlling a target energy self-sufficiency rate from an electric vehicle charging device, an energy generating device, an energy storage device, and an electric vehicle charging device. An electric vehicle charging system including a control device controlling power of at least one of an energy generating device, an energy storage device, and an electric vehicle charging device based on a minimum value that a function may have may be provided.

In addition, the present embodiments further include a power system device that receives power from the energy generating device or supplies power to the energy storage device and the electric vehicle charging device, and includes the power system device, the energy generating device, the energy storage device, and the electric vehicle charging device. Each connected line is equipped with a switch, and the control device supplies a pulse signal to the energy generating device, energy storage device, and electric vehicle charging device to determine whether or not it is in an abnormal state. It is possible to provide an electric vehicle charging system that controls a switch provided in a connection line of a system device to be opened.

The electric vehicle charging system of the present embodiments can control the power of the energy generating device, the energy storage device, and the electric vehicle charging device in an integrated manner, thereby increasing the operating efficiency of the electric vehicle charging system.

In addition, since the electric vehicle charging system of the present embodiments can separate a device in an abnormal state from a power system device, the stability of the electric vehicle charging system can be secured.

1 is a block diagram schematically illustrating an electric vehicle charging system according to the present embodiments.
2 is a block diagram schematically illustrating a control device included in an electric vehicle charging system according to the present embodiments.
3 is a graph showing voltage weights included in information about factors for target voltage control according to the present embodiments.
4 is a block diagram schematically showing information on factors for target energy independence rate control according to the present embodiments.
5 is a graph showing self-reliance rate weights included in information on factors for target energy self-reliance rate control according to the present embodiments.
6 is a block diagram schematically illustrating an electric vehicle charging system according to a further embodiment of the present embodiments.

DETAILED DESCRIPTION Some embodiments of the present disclosure are described in detail below with reference to exemplary drawings. In adding reference numerals to components of each drawing, the same components may have the same numerals as much as possible even if they are displayed on different drawings. In addition, in describing the present embodiments, if it is determined that a detailed description of a related known configuration or function may obscure the gist of the present technical idea, the detailed description may be omitted. When "comprises", "has", "consists of", etc. mentioned in this specification is used, other parts may be added unless "only" is used. In the case where a component is expressed in the singular, it may include the case of including the plural unless otherwise explicitly stated.

Also, terms such as first, second, A, B, (a), and (b) may be used in describing the components of the present disclosure. These terms are only used to distinguish the component from other components, and the nature, sequence, order, or number of the corresponding component is not limited by the term.

In the description of the positional relationship of components, when it is described that two or more components are "connected", "coupled" or "connected", the two or more components are directly "connected", "coupled" or "connected". ", but it will be understood that two or more components and other components may be further "interposed" and "connected", "coupled" or "connected". Here, other components may be included in one or more of two or more components that are “connected”, “coupled” or “connected” to each other.

In the description of the temporal flow relationship related to components, operation methods, production methods, etc., for example, "after", "continued to", "after", "before", etc. Alternatively, when a flow sequence relationship is described, it may also include non-continuous cases unless “immediately” or “directly” is used.

On the other hand, when a numerical value or corresponding information (eg, level, etc.) for a component is mentioned, even if there is no separate explicit description, the numerical value or its corresponding information is not indicated by various factors (eg, process factors, internal or external shocks, noise, etc.) may be interpreted as including an error range that may occur.

1 is a block diagram schematically showing an electric vehicle charging system according to the present embodiments, and FIG. 2 is a block diagram schematically showing a control device included in the electric vehicle charging system according to the present embodiments.

Referring to FIG. 1 , an electric vehicle charging system includes an energy generating device 100, an energy storage device 200, an electric vehicle charging device 300, and a control device 400.

The energy generating device 100 may generate power from renewable energy.

The energy generating device 100 may be a photovoltaic device that generates power from solar energy, but is not limited thereto. For example, the energy generating device 100 may be a wind power generating device generating electric power from wind energy, a hydroelectric generating device generating electric power from potential energy of water, and the like. Also, the energy generating device 100 may be a combination of at least two of photovoltaic power generation, wind power generation, and hydroelectric power generation.

Hereinafter, the energy generating device 100 will be described as an example of a photovoltaic device, but as described above, it is not limited thereto, and the energy generating device 100 according to the present embodiment can generate power from renewable energy. All devices can be included.

The energy storage device 200 may store or convert power supplied from the energy generating device 100 .

The energy storage device 200 may include a battery that stores supplied power and a power condition system (PCS) that converts the supplied power. In addition, the energy storage device 200 may further include a battery management system (BMS) for monitoring the state and operation of the battery and a power management system (PMS) for managing power in the energy storage device. The battery, PCS, BMS, and PMS may be separately provided in the energy storage device 200, but are not limited thereto, and may be integrally provided.

The energy storage device 200 may convert all power supplied from the energy generating device 100 or the remaining power after storing among the power supplied from the energy generating device 100 and supply the converted electric power to the electric vehicle charging device 300 . The energy storage device 200 may convert the stored power and supply it to the electric vehicle charging device 300 .

The electric vehicle charging device 300 may store the converted power supplied from the energy storage device 200 or supply it to the electric vehicle.

The electric vehicle charging device 300 may supply all of the power supplied from the energy storage device 200 to the electric vehicle, but is not limited thereto. For example, the electric vehicle charging device 300 has a separate small battery and a small PCS (Power Condition System) therein to convert and store some of the power supplied from the energy storage device 200 and store the remaining power to the electric vehicle. It is also possible to supply or convert the stored power and supply it to the electric vehicle.

The electric vehicle charging device 300 may be a stand type fixed to the ground, but is not limited thereto, and may be a wall type fixed to a wall.

The electric vehicle charging device 300 may be a slow charging device having supplied power of any one of 3.3kW, 7.7kW, and 15.4kkW, but is not limited thereto, and may be a rapid charging device having 50kW or 100kW. In addition, the electric vehicle charging device 300 may be a combination of a slow charging device and a rapid charging device. The electric vehicle charging device 300 may be provided in plurality as any one of a slow charging device, a rapid charging device, and a combination of a slow charging device and a fast charging device.

The control device 400 obtains information about factors for controlling voltage and factors for controlling energy self-sufficiency from the energy generating device 100, the energy storage device 200, and the electric vehicle charging device 300, respectively, to obtain cost function can be calculated.

Referring to FIGS. 1 and 2 , information 410 on factors for controlling voltage acquired by the control device 400 may include a target voltage 411 , a current voltage 413 , and a voltage weight 415 . can

The target voltage 411 may be a reference value for voltage stabilization of an electric vehicle charging system.

The current voltage 413 may be calculated by comparing an average of the highest voltage and the lowest voltage selected from among the energy generating device 100 , the energy storage device 200 , and the electric vehicle charging device 300 with a target voltage. For example, the current voltage 413 may be calculated as the highest voltage when the average is greater than or equal to the target voltage 411 , and may be calculated as the lowest voltage when the average is less than the target voltage 411 .

The voltage weight 415 is set to different values in the first voltage range, the second voltage range, and the third voltage range divided around the target voltage, and the first voltage range is a positive value and a negative value of the first voltage. The upper and lower limits are the values, and the second voltage range has positive and negative values of the second voltage having a greater absolute value than the first voltage as the upper and lower limits, and does not overlap with the first voltage range, and the third voltage The range may not overlap with the first voltage range and the second voltage range when more than the positive value of the second voltage and less than or equal to the negative value of the second voltage.

The voltage weight 415 is set to a value of 0 in the first voltage range, set to a value that increases in proportion to an increase in the absolute value of voltage in the second voltage range, and set to a constant maximum value in the third voltage range. .

Referring to FIGS. 1 and 2 , information 420 on factors for controlling the energy self-sufficiency rate obtained by the control device 400 includes a target energy self-sufficiency rate 421, a currently predicted energy self-sufficiency rate 423, and A self-reliance rate weight 425 may be included.

The currently predicted energy self-sufficiency rate 423 is calculated by dividing the predicted energy generation amount by the predicted energy consumption amount, and the predicted energy generation amount and the predicted energy consumption amount may be values predicted on a daily basis.

The predicted energy generation amount and the predicted energy consumption amount are based on a value obtained by multiplying a first value, which is the predicted energy amount from the calculation time to the first preset time point, by a correction value, and adding a second value, which is the energy amount from the second preset time point to the calculated time point. can be calculated.

The first value, which is the predicted amount of energy from the calculation time to the first preset time point, may be calculated by a deep learning algorithm using at least one of insolation, temperature, working day, non-working day, and day of the week as an input factor.

The correction value may be calculated by dividing a second value, which is an amount of energy from a preset second time point to a calculated time point, by a third value, which is a predicted amount of energy from a preset second time point to a calculated time point.

The self-reliance rate weight 425 is set to different values in the first time range, the second time range, and the third time range divided based on the second preset time point, and the first time range starts from the second preset time point. The second time range is set from time T1 to time T2, which is after time T1, and the third time range is set from time T2 to a preset first time point after time T2. can be set.

The self-reliance rate weight 425 may be set to a value of 0 in the first time range, set to a value that increases in proportion to time in the second time range, and set to a certain maximum value in the third time range.

The control device 400 may calculate the cost function 430 by Equation 1 below based on the obtained information 410 and 420 on the factors for controlling the voltage and the factors for controlling the energy self-sufficiency rate, respectively. have.

[Equation 1]

: 현재 예측된 에너지 자립률, W_SSR: 자립률 가중치)(J(k): cost function, V ^* : target voltage, V(k): current voltage, W _v : voltage weighting, SSR ^* : target energy independence rate,

: current predicted energy self-sufficiency rate, W _SSR : self-sufficiency rate weight)

The control device 400 controls at least one of the energy generating device 100, the energy storage device 200, and the electric vehicle charging device 300 based on the minimum value 440 that the cost function 430 calculated by Equation 1 can have. One power can be controlled.

The control device 400 controls at least one of the energy generating device 100, the energy storage device 200, and the electric vehicle charging device 300 based on the minimum value 440 that the cost function 430 calculated by Equation 1 can have. One power can be controlled.

The control device 400 may consider the restriction 450 when determining the minimum value 440 that the cost function 430 may have. The restrictions 450 may be the remaining charging amount of the energy storage device 200, the amount of power, the amount of converted power, and the like.

For example, when the control device 400 determines the minimum value 440 that the cost function 430 can have, the maximum value at which the remaining charge of the energy storage device 200 is set to prevent fire and maintain performance of the energy storage device. and whether it is maintained within the range of the minimum value. In addition, when the control device 400 determines the minimum value 440 that the cost function 430 can have, the amount of power supplied to the energy storage device 200 is less than the maximum amount of power determined according to the performance of the energy storage device 200. The maximum amount of converted power determined according to the performance of the energy storage device 200 is the sum of the amount of power converted from the power supplied from the energy generating device 100 and the amount of power converted from the power stored in the energy storage device 200. It can be considered whether it is smaller.

The minimum value 440 that the cost function 430 can have is a range set around the target voltage 411 to keep the current voltage 413 within the normal voltage range where voltage control is not required, and the currently predicted energy The self-reliance rate 423 may be the smallest value that allows the target energy self-reliance rate 421 to be reached. Therefore, the control device 400 predicts that the current voltage 413 in the electric vehicle charging system is out of the normal voltage range or the currently predicted energy self-sufficiency rate 423 of the electric vehicle charging system is out of the target energy self-sufficiency rate 421. In this case, the minimum value 440 that the cost function 430 that allows the currently predicted energy self-sufficiency rate 423 to reach the target energy self-sufficiency rate 411 while allowing the current voltage 413 to fall within the normal voltage range Power of at least one of the energy generating device 100 , the energy storage device 200 , and the electric vehicle charging device 300 may be controlled based on .

For example, the control device 400 determines that the current voltage 413 is a negative voltage out of the normal voltage range and the currently predicted energy self-sufficiency rate 423 is lower than the target energy self-sufficiency rate 421, Based on the minimum value 440 that the cost function 430 that increases the current voltage and increases the currently predicted energy self-sufficiency rate 423, the production power of the energy generating device 100 increases, the energy storage device 200 It is possible to control at least one of converting the stored power and supplying it to the electric vehicle charging device 300 and converting the stored power of the electric vehicle charging device 300 and supplying it to the electric vehicle.

The control device 400 determines the current voltage when the current voltage 413 is a positive voltage out of the normal voltage range and the currently predicted energy self-sufficiency rate 423 is predicted to be higher than the target energy self-sufficiency rate 421. Based on the minimum value 440 that the cost function 430 that lowers the currently predicted energy self-sufficiency rate 423 while decreasing, the production power of the energy generating device 100 is reduced, and the energy storage device 200 At least one of an increase in stored power and an increase in power stored in the electric vehicle charging device 300 may be controlled.

The control device 400 determines whether the current voltage 413 is a negative voltage out of the normal voltage range and the currently predicted energy self-sufficiency rate 423 is predicted to be higher than the target energy self-sufficiency rate 421 or the current voltage 413 ) is a positive voltage out of the normal voltage range, and if the currently predicted energy self-sufficiency rate 423 is predicted to be lower than the target energy self-sufficiency rate 421, among the voltage weight 415 and the self-sufficiency rate weight 425 Controls the power of at least one of the energy generating device 100, the energy storage device 200, and the electric vehicle charging device 300 based on the minimum value 440 that the cost function 430 can have with weight on the larger value can do.

Although not shown in FIGS. 1 and 2 , the electric vehicle charging system may further include a power system device that receives power from the energy generating device 100 or supplies power to the energy storage device 200 and the electric vehicle charging device 300. can A switch may be provided on each line connecting the power system device, the energy generating device 100, the energy storage device 200, and the electric vehicle charging device 300. The control device 400 supplies a pulse signal to the energy generating device 100, the energy storage device 200, and the electric vehicle charging device 300 to determine whether or not an abnormal state exists, and if it is determined to be an abnormal state, the device in the abnormal state A switch provided in a connection line of a power system device may be controlled to open. A specific embodiment related to this will be described later with reference to FIG. 6 .

The above-described electric vehicle charging system can control the power of the energy generating device 100, the energy storage device 200, and the electric vehicle charging device 300 in an integrated manner, thereby increasing the operating efficiency of the electric vehicle charging system. In addition, since the above-described electric vehicle charging system can separate a device in an abnormal state from a power system device, the stability of the electric vehicle charging system can be secured.

In the above-described embodiment, the preset first time point may be set to a value equal to or greater than time T2, and the preset second point of time may be set to a value equal to or less than time T1 without limitation.

Hereinafter, the first preset time point is the end of the day, and the second preset time is the start of the day. The end of the day may be a term with the same meaning as the first preset time, The starting time point may be a term having the same meaning as a preset second time point.

Also, in the above-described embodiment, the term present may have the same meaning as the calculation time point, and in the embodiments described below, the term present may also have the same meaning as the calculation time point.

Below, various embodiments of an electric vehicle charging system will be described with reference to the drawings.

Referring back to FIG. 2 , the information 410 on factors for voltage control may include a target voltage 411 , a current voltage 413 , and a voltage weight 415 .

The target voltage 411 may be a value set by the control device 400 as a reference for controlling the voltage of the electric vehicle charging system. The target voltage 411 may be a constant fixed value, but is not limited thereto, and may be a variable value set differently according to weather, temperature, and the like.

The current voltage 413 may be calculated by the control device 400 based on information about voltages of the energy generating device 100, the energy storage device 200, and the electric vehicle charging device 300 in the electric vehicle charging system.

Specifically, the current voltage 413 is calculated by comparing the target voltage 411 with the average of the highest and lowest voltages selected from among the energy generating device 100, the energy storage device 200, and the electric vehicle charging device 300. It can be. For example, the current voltage 413 may be calculated as the highest voltage when the average is greater than or equal to the target voltage 411 , and may be calculated as the lowest voltage when the average is less than the target voltage 411 .

When selecting the highest voltage and the lowest voltage, the control device 400 may further consider the voltage of the load device in addition to the voltages of the energy generating device 100 , the energy storage device 200 , and the electric vehicle charging device 300 . The load device may include all loads for maintaining and improving performance in an electric vehicle charging system, such as air conditioners and lights.

The average of the highest and lowest voltages is to determine the degree of deviation from the center of the target voltage 411, and the current voltage 413 is calculated as the highest or lowest voltage that deviated further from the target voltage. do.

Accordingly, the control device 400 may calculate the voltage of the device most distant from the target voltage 411 as the current voltage 413 .

The voltage weight 415 is a value that is weighted according to the degree to which the current voltage deviates from the target voltage, and may be a value set by the control device.

3 is a graph showing voltage weights included in information about factors for target voltage control according to the present embodiments.

Referring to FIGS. 2 and 3 , the voltage weight 415 may be set to different values in a first voltage range, a second voltage range, and a third voltage range centered on a target voltage 411 (V ^* ). have. The first voltage range has positive and negative values of the first voltage as upper and lower limits, and the second voltage range has positive and negative values of the second voltage having a greater absolute value than the first voltage as upper and lower limits. It is set as a lower limit and does not overlap with the first voltage range, and the third voltage range may not overlap with the first voltage range and the second voltage range above the positive value of the second voltage and below the negative value of the second voltage. .

The first voltage range, the second voltage range, and the third voltage range are experimentally obtained ranges, and are the power generation performance of the energy generating device 100, the storage performance of the energy storage device 200 and the electric vehicle charging device 300, and the installed electric vehicle. Each of the first voltage range, the second voltage range, and the third voltage range may be set to be wider or narrower according to the temperature and environment around the charging system.

The voltage weight 415 may be set to a value of 0 in the first voltage range. Accordingly, the first voltage range is a range set based on the target voltage 411 (V ^* ) and may be a normal voltage range in which voltage control is not required. The normal voltage range may have a positive voltage and a negative voltage that deviate from 4% of the target voltage (411, V ^* ) as upper and lower limits, but are not limited thereto, and the normal voltage range may be set differently. .

Since the voltage weight is 0 when the current voltage 413 is within the first voltage range, the cost function 430 calculated by the control device 400 may be a function for controlling the energy self-sufficiency rate.

The voltage weight 415 may be set to a value that increases in proportion to an increase in absolute value of voltage in the second voltage range. As the current voltage 413 is within the second voltage range and further away from the target voltage 411 (V ^* ), the voltage weight increases so as to control the voltage in the cost function 430 calculated by the control device 400. The influence of factors for this can gradually increase.

Referring to FIG. 3 , the voltage weight 415 is shown to increase linearly from 0 in proportion to an increase in the absolute value of the voltage in the second voltage range, but is not limited thereto. The voltage weight 415 may increase nonlinearly from 0 in proportion to an increase in absolute value in the second voltage range.

The voltage weight 415 may be set to a constant maximum value in the third voltage range. As shown in FIG. 3 , the constant maximum value of the voltage weight 415 may be the same as the maximum value of the voltage weight 415 in the second voltage range. The maximum value of the voltage weighting factor 415 may be a limit value for preventing instability due to rapid change in the voltage of each device in the electric vehicle charging system.

When the calculated current voltage 413 is within the third voltage range, the voltage weight 415 is constant at the maximum value, so that the effect of the factor for controlling the voltage in the cost function 430 calculated by the control device 400 is maximum. can be

Although not shown in FIG. 3 , the current voltage 413 to which the voltage weight 415 is assigned may be set as a threshold voltage as a threshold value. The threshold voltage may have upper and lower limits of a positive value and a negative value of a voltage deviating from the target voltage 411 (V ^* ) by 6%, but may be set differently. The threshold voltage may be set within the second voltage range, but is not limited thereto, and may be set within the third voltage range. According to the threshold voltage setting, the voltage of each device in the electric vehicle charging system can be controlled within the threshold voltage.

4 is a block diagram schematically showing information on factors for controlling the target energy self-sufficiency rate according to the present embodiments, and FIG. 5 is included in the information on factors for controlling the target energy self-sufficiency rate according to the present embodiments. It is a graph showing the self-reliance rate weight.

Referring to FIG. 4 , information 420 on factors for controlling the target energy self-sufficiency rate obtained by the control device 400 includes a target energy self-sufficiency rate 421, a currently predicted energy self-sufficiency rate 423, and self-sufficiency rate 423. Rate weights 425 may be included.

The target energy self-sufficiency rate 421 may be set to a value of 100% when only the energy generating device 100 supplies power to the energy storage device 200 within the electric vehicle charging system. . However, the electric vehicle charging system may further include a power system device, and in this case, the target energy self-sufficiency rate 421 may be set to an arbitrary value less than 100% or an arbitrary range.

The currently predicted energy independence rate 423 is calculated by dividing the predicted energy generation 423a by the predicted energy consumption 423b, and the predicted energy generation 423a and the predicted energy consumption 423b can be predicted on a daily basis. .

The predicted energy generation amount 423a is the predicted amount of energy predicted to be produced by the energy generating device 100 on a daily basis, the predicted energy amount predicted to supply the energy stored in the energy storage device 200 to the electric vehicle charging device, and the electric vehicle. The energy stored in the charging device 300 is calculated as the sum of predicted energy quantities expected to be supplied to the electric vehicle.

The predicted energy consumption 423b may be calculated as the sum of the predicted energy predicted to be stored by the energy storage device 200 on a daily basis and the predicted energy predicted to be stored by the electric vehicle charging device 300 or supplied to the electric vehicle. The predicted energy consumption 423b is calculated by considering the estimated energy consumption predicted to be consumed by the load device in addition to the energy storage device 200 and the electric vehicle charging device 300 and the estimated loss energy predicted to be lost in the power supply process. can be summed up.

The predicted energy generation amount (423a) and the predicted energy consumption amount (423b) are obtained by multiplying the first value, which is the predicted amount of energy 427 from the time of calculation to the end of the day, by the correction value 429, and the amount of energy from the start of the day to the time of calculation (428 ) may be calculated based on the value obtained by adding the second value.

Specifically, the energy generation predicted amount 423a and the energy consumption predicted amount 423b may be calculated based on the current daily energy predicted amount according to Equation 2 below.

[Equation 2]

: 하루 시작 시점부터 산출 시점까지의 에너지량인 제2 값,

: 산출 시점부터 하루 종료 시점까지의 예측 에너지량인 제1 값, α: 보정치)(E ^T : Current daily energy forecast,

: The second value, which is the amount of energy from the start of the day to the time of calculation,

: The first value, which is the predicted energy amount from the time of calculation to the end of the day, α: correction value)

The second value, which is the amount of energy 428 from the start of the day to the present, can be calculated as the sum of the amount of power at each point from the start of the day to the point of calculation, and the predicted amount of energy from the point of calculation to the end of the day ( 427) may be calculated as the sum of predicted power amounts at each time point from immediately after the present to the end of the day.

The first value, which is the predicted amount of energy 427 from the time of calculation to the end of the day, may be calculated by a deep learning algorithm using at least one of insolation, temperature, working day, non-working day, and day of the week as an input factor.

For example, the predicted amount of energy 427 from the time of calculation of the energy generating device 100 to the end of the day may have at least one of insolation and temperature as an input factor, and on sunny days when there is a lot of insolation or high temperature, value can be predicted.

The predicted amount of energy 427 from the time of calculation of the electric vehicle charging device 300 to the end of the day may use at least one of working days, non-working days, and days of the week as an input factor, and may be predicted as a high value on non-working days or non-working days. There is, and it can be predicted as a high or low value depending on the usage pattern of the electric vehicle charging system for each day of the week.

The predicted amount of energy 427 from the time of calculation of the energy storage device 200 to the end of the day may use at least one of working days, non-working days, and days of the week as an input factor, and may be predicted as a high value on non-working days or working days. There is, and it can be predicted as a high or low value depending on the usage pattern of the electric vehicle charging system for each day of the week.

The predicted amount of energy 427 from the time of calculating the load device to the end of the day may use at least one of temperature, working day, non-working day, and day of the week as an input factor, and is predicted to be a high value due to the use of an air conditioner on a day with high temperature. It can be, and it can be predicted as a high value due to the increase in the number of customers using the electric vehicle charging system on holidays.

The predicted amount of energy 427 from the point of calculation related to the loss to the end of the day may use at least one of temperature, workday, and day of the week as an input factor, and is predicted to be a low value on workdays when there are few visits by customers using the electric vehicle charging system. It can be, and it can be predicted as a high or low value according to the usage pattern of the electric vehicle charging system for each day of the week.

The deep learning algorithm used to calculate the first value, which is the predicted energy amount 427 from the calculation time to the end of the day, may be a commonly used algorithm, but preferably LSTM (Long Short-Term Memory models) can

The correction value 429 may be calculated by dividing the second value, which is the amount of energy 428 from the start of the day to the time of calculation, by the third value, which is the predicted amount of energy from the start of the day to the time of calculation.

The correction value 429 is a factor for correcting an error between the predicted amount of energy and the actual amount of energy from the start of the day to the point of calculation. Accordingly, the correction value 429 may correct the first value, which is the predicted energy amount 427, from the calculation time point, which varies according to the time point, to the end of the day, to accurately predict the current daily standard energy estimate.

The self-reliance rate weight 425 is a value that is weighted over time and may be a value set by the control device 400 .

Referring to FIG. 5, the self-reliance rate weight 425 is set to different values in the first time range, the second time range, and the third time range divided based on the start of the day, and the first time range is the start of the day. It is set from the time point to time T1, which is after the start of the day, and the second time range is set from time T1 to time T2, which is after time T1. The third time range may be set from the time T2 to the end of the day after the time T2.

The first time range, the second time range, and the third time range are ranges obtained empirically, and whether controllable factors can be specified, the generation time of the energy generating device 100, the usage pattern of customers using the electric vehicle charging system, etc. Each of the first time range, the second visual range, and the third time range may be set to be wider or narrower according to time points T1 and T2, which are set in consideration.

Time T1 may be a time point when a controllable factor can be specified, the energy generating device 100 starts producing energy, and the number of customers using the electric vehicle charging system increases. Time T2 may be a point in time when controllable factors are limited, energy production of the energy generating device 100 is reduced or stopped, and customers using the electric vehicle charging system are steady. For example, the time T1 may be a specific time between 9:00 am and 12:00 am, and the time T2 may be a specific time between 3:00 pm and 6:00 pm, but is not limited thereto and may be set differently.

The self-reliance rate weight 425 may be set to a value of 0 in the first time range, set to a value that increases in proportion to time in the second time range, and set to a certain maximum value in the third time range.

The self-reliance rate weight 425 may be set to a value of 0 in the first time range. The first time range is a section in which the currently predicted energy self-sufficiency rate 423 is highly likely to change because a factor capable of controlling the energy self-sufficiency rate is not specified, and may be a section in which control of the energy self-sufficiency rate is not required. When the calculation point of the currently predicted energy self-sufficiency rate 423 is within the first time range, the self-sufficiency rate weight 425 is 0, so the cost function 430 calculated by the control device 400 is can be a function

The self-reliance rate weight 425 may be set to a value that increases in proportion to the passage of time in the second time range. The second time range may be a period in which the need for controlling the energy self-sufficiency rate gradually increases because a factor capable of changing the currently predicted energy self-sufficiency rate 423 can be specified. If the calculation point of the currently predicted energy self-sufficiency rate 423 is within the second time range, the self-sufficiency rate weight 425 increases with the lapse of time, and the cost function 430 calculated by the control device 400 The influence of factors for controlling the self-reliance rate may gradually increase.

Referring to FIG. 5 , the self-reliance rate weight 425 is shown to increase linearly from 0 in proportion to the passage of time in the second time range, but is not limited thereto. For example, the self-sufficiency rate weight 425 is non-linear in consideration of Time Of Use (TOU), Real-Time Pricing (RTP), and Levelized Cost Of Electricity (LCOE). may be incrementally increased.

The self-reliance rate weight 425 may be set to a certain maximum value in the third time range. As shown in FIG. 5 , the constant maximum value of the self-reliance rate weight 425 may be the same as the maximum value of the self-reliance rate weight in the second time range. The third time range may be a section in which the need for control of the energy self-sufficiency rate is very great because factors capable of changing the currently predicted energy self-sufficiency rate 423 are limited. If the calculation point of the currently predicted energy self-sufficiency rate 423 is within the third time range, the weight self-sufficiency rate 425 is constant at the maximum value, so that the cost function 430 calculated by the control device 400 determines the energy self-sufficiency rate. The influence of the factor for control can be maximal.

As described above, the electric vehicle charging system of the present embodiments can control the power of the energy generating device 100, the energy storage device 200, and the electric vehicle charging device 300 in an integrated manner, thereby increasing the operating efficiency of the electric vehicle charging system. can

6 is a block diagram schematically illustrating an electric vehicle charging system according to a further embodiment of the present embodiments.

Referring to FIG. 6 , the electric vehicle charging system may further include a power system device 500 that receives power from the energy generating device 100 or supplies power to the energy storage device 200 and the electric vehicle charging device 300. have.

The power system device 500 may receive power remaining after being produced from the energy generating device 100 and supplied to the energy storage device 100, and the energy storage device 200 in short supply from the energy generating device 100 and Power may be supplied to the electric vehicle charging device 300 .

Switches S1, S2, and S3 may be provided on each line connecting the power system device 500, the energy generating device 100, the energy storage device 200, and the electric vehicle charging device 300. The switches S1, S2, and S3 may be opened by a signal supplied by the control device 400.

The control device 400 may supply pulse signals to the energy generating device 100, the energy storage device 200, and the electric vehicle charging device 300 to determine whether or not they are in an abnormal state. The pulse signal supplied by the control device 400 is a direct current voltage and may be a signal of alternating 0V voltage and +5V voltage, but is not limited thereto, and may include both signals of alternating low voltage and high voltage.

The control device 400 determines whether the device is in an abnormal state by receiving a change in the supplied pulse signal. For example, when the control device 400 receives that the pulse signal supplied to the energy storage device 200 does not change, it may determine that the energy storage device 200 stops operating and is in an abnormal state.

When it is determined that the control device 400 is in an abnormal state, the control device 400 may control the switches S1 , S2 , and S3 provided on the connection line between the device in the abnormal state and the power system device 500 to be opened. For example, when the energy storage device 200 is determined to be abnormal, the control device 400 switches S1, S2, and S3 provided on a connection line between the energy storage device 200 and the power system device 500. can be controlled to open.

Although the foregoing embodiment has been described as an example of the energy storage device 200 being in an abnormal state, it is not limited thereto, and the foregoing embodiment may also be applied to the energy generating device 100 or the electric vehicle charging device 300.

Since the electric vehicle charging system of the present embodiments described above can separate the device in an abnormal state from the power system device, the stability of the electric vehicle charging system can be secured.

The above description is merely illustrative of the technical idea of the present disclosure, and various modifications and variations can be made to those skilled in the art without departing from the essential characteristics of the technical idea. In addition, since the present embodiments are not intended to limit the technical idea of the present disclosure, but to explain, the scope of the present technical idea is not limited by these embodiments. The scope of protection of the present disclosure should be construed by the following claims, and all technical ideas within the scope equivalent thereto should be construed as being included in the scope of rights of the present disclosure.

100: energy generating device 200: energy storage device
300: electric vehicle charging device 400: control device
410: voltage control factor information 411: target voltage
413 current voltage 415 voltage weighting
420: energy self-sufficiency rate control factor information 421: target energy self-sufficiency rate
423: current predicted energy self-sufficiency rate 425: self-sufficiency rate weight
430: cost function 440: minimum cost function
500: power system device S1, S2, S3: switch

Claims (17)

energy generating devices that produce power from renewable energy;
an energy storage device that stores or converts power supplied from the energy generating device;
an electric vehicle charging device that stores the converted power supplied from the energy storage device or supplies it to the electric vehicle; and
A cost function is calculated by obtaining information on factors for controlling voltage and factors for controlling energy self-sufficiency rate from the energy generating device, energy storage device, and electric vehicle charging device, and the minimum value that the calculated cost function can have A control device for controlling power of at least one of the energy generating device, the energy storage device, and the electric vehicle charging device based on
Information on the factor for controlling the voltage,
contains target voltage, current voltage and voltage weight;
The current voltage is,
An electric vehicle charging system calculated by comparing an average of the highest voltage and the lowest voltage selected from the energy generating device, the energy storage device, and the electric vehicle charging device with a target voltage. delete delete According to claim 1,
The current voltage is,
An electric vehicle charging system, characterized in that when the average is greater than the target voltage, the highest voltage is calculated. According to claim 1,
The current voltage is,
An electric vehicle charging system, characterized in that when the average is less than the target voltage, the lowest voltage is calculated. According to claim 1,
The voltage weights are set to different values in a first voltage range, a second voltage range, and a third voltage range divided around the target voltage,
The first voltage range has a positive value and a negative value of the first voltage as upper and lower limits,
The second voltage range has positive and negative values of the second voltage having a greater absolute value than the first voltage as upper and lower limits and does not overlap with the first voltage range,
The electric vehicle charging system, characterized in that the third voltage range does not overlap with the first voltage range and the second voltage range when more than the positive value of the second voltage and less than the negative value of the second voltage. ◈Claim 7 was abandoned when the registration fee was paid.◈ According to claim 6,
The voltage weight is,
An electric vehicle charging system, characterized in that set to a value of 0 in the first voltage range. ◈Claim 8 was abandoned when the registration fee was paid.◈ According to claim 6,
The voltage weight is,
An electric vehicle charging system, characterized in that set to a value that increases in proportion to the increase in the absolute value of the voltage in the second voltage range. ◈Claim 9 was abandoned when the registration fee was paid.◈ According to claim 6,
The voltage weight is,
An electric vehicle charging system, characterized in that set to a constant maximum value in the third voltage range. According to claim 1,
Information on factors for controlling the energy self-sufficiency rate,
An electric vehicle charging system comprising a target energy self-sufficiency rate, a currently predicted energy self-sufficiency rate, and a self-sufficiency rate weight. According to claim 10,
The currently predicted energy self-sufficiency rate is,
It is calculated by dividing the energy generation forecast by the energy consumption forecast,
The electric vehicle charging system, characterized in that the predicted energy generation amount and the predicted energy consumption amount are predicted on a daily basis. According to claim 11,
The energy generation predicted amount and energy consumption predicted amount,
An electric vehicle characterized in that it is calculated based on a value obtained by multiplying a first value, which is the amount of predicted energy from the time of calculation to the first time in advance, by a correction value, and adding a second value, which is the amount of energy from the second time in advance to the time of calculation. charging system. ◈Claim 13 was abandoned when the registration fee was paid.◈ According to claim 12,
The first value is,
An electric vehicle charging system, characterized in that calculated by a deep learning algorithm using at least one of solar radiation, temperature, working day, non-working day, and day of the week as an input factor. ◈Claim 14 was abandoned when the registration fee was paid.◈ According to claim 12,
The correction value is
The electric vehicle charging system, characterized in that calculated by dividing the second value by a third value, which is a predicted amount of energy predicted from a preset second time point to a calculated time point. According to claim 10,
The self-reliance rate weight is set to different values in a first time range, a second time range, and a third time range divided based on a preset second time point,
The first time range is set from a preset second time point to a time point T1 after the second time point,
The second time range is set from time T1 to time T2 after time T1,
The electric vehicle charging system, characterized in that the third time range is set from time T2 to a first preset time point after time T2. According to claim 15,
The self-reliance rate weight,
The electric vehicle charging system, characterized in that set to a value of 0 in the first time range, set to a value that increases in proportion to time in the second time range, and set to a constant maximum value in the third time range. According to claim 1,
Further comprising a power system device receiving power from the energy generating device or supplying power to the energy storage device and the electric vehicle charging device;
A switch is provided on each line connecting the power system device, the energy generating device, the energy storage device, and the electric vehicle charging device,
The control device supplies a pulse signal to an energy generating device, an energy storage device, and an electric vehicle charging device to determine whether or not an abnormal state exists. An electric vehicle charging system, characterized in that controlled to open.

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