KR102460177B1 - Method of grading electric vehicle charger and evaluation method of charging performance related to electric vehicle - Google Patents

Abstract

The present invention provides a method for determining the management grade of an electric vehicle charger and a method for evaluating charging performance in connection with an electric vehicle. The method for determining the management grade of an electric vehicle charger comprises the steps of: measuring, by a power meter for determining the management grade of an electric vehicle charger and evaluating performance in connection with an electric vehicle, power consumed by the electric vehicle charger when the electric vehicle charger is in a standby mode; connecting the electric vehicle charger and a load to start charging, and calculating charging power transfer efficiency, which is the ratio of output power and input power of the electric vehicle charger when the output power of the electric vehicle charger is maximum during the charging; measuring power consumed by the electric vehicle charger when the electric vehicle charger is in a standby mode after the charging is finished; and determining the management grade of the electric vehicle charger, based on the power consumed by the electric vehicle charger and the charging power transfer efficiency. Therefore, the method can reflect operating cost factors, thereby enabling the electric vehicle charger to be systematically classified and managed.

Description

Method of grading electric vehicle charger and evaluation method of charging performance linked to electric vehicle

The present invention relates to a method for evaluating the charging performance of an electric vehicle charger.

An electric vehicle charger (hereinafter abbreviated as 'charger') can be used as a charger if it meets the electrical specifications and standards presented in the standard. Compatibility issues arise.

In addition, since the information related to the performance of the charger can only know whether or not a standard or specification is satisfied, conformity, or certification result, there is a lack of standards for comparing performance between chargers.

In particular, in the case of a charger that consumes a lot of power in the standby state before and after charging, not while charging the electric vehicle, the operating cost is relatively large, A charger with low charging power transmission efficiency, which is the ratio of the input power of the charger to the actual charging power delivered to the device, also increases the operating cost. For example, as the electric vehicle charger is in a continuous standby state while the system power is supplied, or maintains the standby state for a certain period of time or more after the electric vehicle charging is finished, power consumption not directly related to electric vehicle charging occurs. However, there is a problem in that it is difficult to select an optimal charger when constructing a charging infrastructure because there is no charger evaluation standard that considers such an operating cost increase factor in the prior art.

In addition, in the conventional charger evaluation method, it is common to evaluate the charging efficiency of the charger under constant voltage and current conditions. However, in the actual charging process of an electric vehicle, the voltage varies during charging, and although the charging efficiency of the charger varies depending on the charging algorithm of the electric vehicle, the conventional charger evaluation method does not reflect this point and thus cannot be evaluated. There is this.

The present invention allows to systematically classify and manage electric vehicle chargers by reflecting operating cost generation factors in order to solve the above-mentioned problems, and to support more efficient and optimized charger selection/operation when constructing electric vehicle charging infrastructure An object of the present invention is to provide a method for rating a charger that can be used.

In addition, when the electric energy delivered to the battery in the vehicle is discharged through the discharge path while driving, when the electric vehicle is charged, different charging methods vary depending on the charging control method of the electric vehicle, the charging/discharging path inside the electric vehicle, and the charging/discharging efficiency of the battery. Because it can represent /discharge performance, the present invention is an electric vehicle that can compare charging performance according to a combination of a charger and an electric vehicle for a plurality of chargers and/or a plurality of electric vehicles through a test in which the charging algorithm of an electric vehicle is reflected An object of the present invention is to provide a vehicle-linked charging performance evaluation method.

Another object of the present invention is to provide a power meter for charger rating determination and electric vehicle-linked charging performance evaluation, and to present a standardized test procedure and environment for objective evaluation.

In the method for determining the operation grade of the electric vehicle charger according to an embodiment of the present invention for achieving the above object, the 'standby state power consumption measurement step before charging' of measuring the power consumed by the charger when the electric vehicle charger is in a standby state ; connecting the charger and the load to start charging, and calculating the charging power transfer efficiency, which is the ratio of the output power to the input power of the charger when the output power of the charger is maximum in the charging process; 'Standby power consumption measurement step after charging' of measuring the power consumed by the charger when the charger is in a standby state after charging is finished; And the 'standby state power consumption measurement step before charging' and the 'standby state power consumption measurement step after charging', the average value of the power consumed in the charger and the charging power transfer efficiency, based on the charging power transfer efficiency is determined including;

When the charger is a DC charger, the load may operate in either a constant voltage mode or a constant current mode during the charging process.

When the charger is an AC charger, the load may operate in either a constant resistance mode or a constant current mode during the charging process.

In the step of determining the charger operation grade, the lower operation grade of the charger operation grade determined based on the average value of power consumed by the charger and the charger operation grade determined based on the charging power transfer efficiency is the final operation of the charger It may be judging by grade.

And, in the charger-electric vehicle linked charging performance evaluation method according to an embodiment of the present invention, the charger and the electric vehicle are connected and the battery of the electric vehicle is maintained until charging is terminated by the charging control algorithm of the electric vehicle. charging; discharging according to a predetermined pre-evaluation pattern until the electric vehicle stops discharging; connecting the electric vehicle to the charger, starting charging, and accumulating the instantaneous power measured at the input side of the charger to calculate the amount of input power to the charger; discharging until the electric vehicle stops discharging according to a predetermined electric charge evaluation pattern, and calculating the amount of discharging power of the battery of the electric vehicle; and calculating a charger-electric vehicle linkage charging rate, which is a ratio of the amount of discharging power and the amount of input power to the charger.

And, the electric vehicle charger operation grade determination and charger-electric vehicle linkage charging performance evaluation method according to an embodiment of the present invention measures the standby state consumption power of the electric vehicle charger, and after connecting the charger and the electric vehicle, After calculating the charging power transfer efficiency of the charger through the process of charging the electric vehicle battery, the charger operation grade primary determination for determining the operation grade of the charger based on the standby state consumption power and the charging power transfer efficiency step; Measure the standby power consumption of the charger again, connect the charger and the electric vehicle, calculate the amount of input power to the charger through the process of charging the electric vehicle battery, and After calculating the charging power transfer efficiency again, the charger input power amount calculation and charger operation class secondary determination step for determining the operation grade of the charger based on the re-measured standby state consumption power and the re-calculated charging power transfer efficiency ; and a discharging power amount and a linked charging rate for calculating a battery discharge power amount of the electric vehicle through the discharging process of the electric vehicle battery, and calculating a linkage charge rate between the charger and the electric vehicle by obtaining a ratio of the discharge power amount and the charger input power amount calculation step;

The charging of the battery may be performed according to the charging control algorithm of the electric vehicle in the first determining step of the charger operation grade and the calculating of the input power amount of the charger and the second determining of the operating level of the charger.

And, the power meter for determining the charger operation grade according to an embodiment of the present invention measures the voltage and current of the input side and the output side of the electric vehicle charger, and using the measured values of the voltage and current, the standby of the charger a measurement unit for calculating state consumption power, input power, and output power; and calculating the ratio of output power and input power when the output power is the maximum to obtain charging power transfer efficiency, and determining the charger operation grade to determine the charger operation grade based on the standby state consumption power and the charging power transfer efficiency includes wealth.

And, the power meter for evaluating the charger-electric vehicle linked charging performance according to an embodiment of the present invention, the voltage and current of the input side of the electric vehicle charger and the output side of the electric vehicle battery (including the 'input/output side of the battery') a measuring unit that measures the voltage and uses the measured values of the voltage and current, and calculates the amount of input power of the charger and the amount of discharge power of the battery; and a linked charging performance evaluation unit for calculating a linked charging rate between a charger and an electric vehicle based on the amount of input power and the amount of discharging power.

And, the power meter for determining the charger operation grade and evaluating the linked charging performance according to an embodiment of the present invention measures the voltage and current of each input side and the output side of the electric vehicle charger and the electric vehicle battery, and a measuring unit for calculating standby state consumption power, input power, output power, input power amount, and discharge power amount of the battery by using the measured value; A charger operation grade determination unit for calculating a ratio of output power and input power when the output power is maximum to obtain a charging power transmission efficiency, and determining a charger operation grade based on the standby state consumption power and the charging power transmission efficiency ; and a linked charging performance evaluation unit for calculating a linked charging rate between a charger and an electric vehicle based on the amount of input power and the amount of discharging power.

According to an embodiment of the present invention, when charging an electric vehicle using a specific charger, it is possible to intuitively know the relative performance advantage compared to other chargers, and to easily determine which charger is advantageous in terms of charger operation. .

According to an embodiment of the present invention, since a specific electric vehicle can be compared based on the connected charging rate to determine which charger has the best charging performance when connected with a specific electric vehicle, it is possible to promote more efficient use from the standpoint of the electric vehicle user, It has the effect of being able to objectively judge the charger product.

1 is a block diagram showing the configuration of a power meter according to an embodiment of the present invention.
2 is a flowchart illustrating a method for determining a charger operating rating according to an embodiment of the present invention.
3A to 3D are diagrams illustrating a test configuration for determining a charger operating grade according to an embodiment of the present invention.
4 is a flowchart illustrating a charger-electric vehicle linkage charging performance evaluation method according to an embodiment of the present invention.
5A and 5B are diagrams showing a test configuration for evaluating charger-electric vehicle-linked charging performance according to an embodiment of the present invention.
6 is a flowchart illustrating a method for determining a charger operating grade and evaluating a connected charging performance according to an embodiment of the present invention.
7A to 7C are detailed flowcharts of a method for determining a charger operating grade and evaluating a linked charging performance according to an embodiment of the present invention.

Advantages and features of the present invention and methods of achieving them will become apparent with reference to the embodiments described below in detail in conjunction with the accompanying drawings. However, the present invention is not limited to the embodiments disclosed below, but will be implemented in a variety of different forms, only these embodiments allow the disclosure of the present invention to be complete, and common knowledge in the technical field to which the present invention belongs It is provided to fully inform the possessor of the scope of the invention, and the present invention is only defined by the scope of the claims. Meanwhile, the terminology used herein is for the purpose of describing the embodiments and is not intended to limit the present invention. In this specification, the singular also includes the plural, unless specifically stated otherwise in the phrase. As used herein, "comprises" and/or "comprising" refers to the presence of one or more other components, steps, operations and/or elements mentioned. or addition is not excluded.

In describing the present invention, if it is determined that a detailed description of a related known technology may unnecessarily obscure the gist of the present invention, the detailed description thereof will be omitted.

The present invention is characterized by presenting a rating determination method of an electric vehicle charger and a charging performance evaluation method of a charger in connection with an electric vehicle, which did not exist in the prior art. The charger rating method according to the present invention does not evaluate the charger simply by classifying it according to the capacity of the charger or achieving the electrical specifications suggested by the standard like the conventional charger evaluation method, but rather, the standby state power consumption before/after charging. And by classifying the grades based on the charging power transfer efficiency using the electric vehicle simulating device as a load, it is possible to select a charger that minimizes operating costs by comparing the operating grades between chargers. That is, it is possible to know which charger has better operational efficiency through the comparison of operating grades for chargers of the same class. It should be understood that the charger class classification standard and the charger operating grade standard presented in the present invention are one example, and the scope of the present invention is the classification of the class illustrated in the description of the charger operation grade determination method of the present invention, the classification of the class, It should not be interpreted as being limited to the figure of the power consumption of the charger in the standby state and the figure of the charging power transfer efficiency of the charger.

In addition, the charging performance evaluation method of the charger linked to the electric vehicle according to the present invention (hereinafter abbreviated as 'linked charging performance evaluation method') is different from the conventional one by using an actual electric vehicle as a load, so that the charging control algorithm of the vehicle is applied. By evaluating the performance of the charger, it is characterized in that it is possible to obtain an evaluation result that is more consistent with reality. According to the method for evaluating the linked charging performance of the present invention, it is possible to evaluate the suitability between the electric vehicle and the charger, and it is possible to compare the charging performance between the chargers for a specific electric vehicle. In other words, when charging a charger in connection with a specific electric vehicle, it is most efficient to charge with which charger for a specific electric vehicle, and the charging performance evaluation (test) that can determine whether the actual amount of charging/discharging electric energy according to charging is the largest A method is proposed in the present invention.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. In describing the present invention, the same reference numerals are used for the same means regardless of the reference numerals in order to facilitate the overall understanding.

1 is a block diagram showing the configuration of a power meter 100 according to an embodiment of the present invention.

The power meter 100 according to an embodiment of the present invention may be used to perform the charger rating method and the linked charging performance evaluation method according to the present invention. The power meter 100 according to an embodiment of the present invention is based on the current and voltage measured at the input side and the output side of the charger and the input side and the output side of the electric vehicle battery (including the 'input/output side of the battery'), the charger operating rating and calculate the linkage charging rate between the charger and the electric vehicle. In the present invention, the term 'input/output side of the battery' means a part with the corresponding terminal when the same terminal is used for input and output of the battery, and 'output side of the battery' refers to a case where the input and output terminals of the battery are different. A portion having an output terminal of , as well as a portion having a corresponding terminal when the same input and output terminals are used, such as the 'input/output side of the battery', is included.

As shown in FIG. 1 , the power meter 100 according to an embodiment of the present invention includes a measuring unit 110 , a charger operation grade determining unit 120 , and a linked charging performance evaluation unit 130 . In addition, the power meter 100 according to an embodiment of the present invention may further include a storage unit 140 .

The measuring unit 110 measures the voltage and current of the input/output side of the charger and the electric vehicle battery, calculates power using the voltage/current measurement value, and accumulates power to calculate the amount of power. In addition, the measuring unit 110 calculates the power consumption in the charger standby state by using the voltage/current measurement value, and calculates the instantaneous power and input power amount of the charger input side and the instantaneous power of the charger output side. In addition, the measurement unit 110 calculates the instantaneous power and input power amount of the battery input side during charging using the voltage/current measurement value, and the instantaneous moment of the electric vehicle battery output side (including 'input/output side of the battery') during discharging. Calculate power and discharge power.

The charger operation grade determination unit 120 calculates the charging power transfer efficiency by dividing the charger output power value by the input power value, and determines the charger operation grade based on the standby state consumption power and the charging power transfer efficiency of the charger maximum output condition. .

The linked charging performance evaluation unit 130 calculates the linked charging rate between the charger and the electric vehicle based on the amount of power input to the charger and the amount of discharging power of the electric vehicle battery. In addition, the linked charging performance evaluation unit 130 compares and evaluates the linked charging rate for each electric vehicle with respect to the evaluation target charger.

The storage unit 140 stores power and power amount data calculated by the measurement unit 110 . In addition, the storage unit 140 stores the linked charging rate between the charger and the electric vehicle calculated by the linked charging performance evaluation unit 130 .

2 is a flowchart illustrating a method for determining a charger operating grade according to an embodiment of the present invention. The charger operation grade determination method according to an embodiment of the present invention calculates the standby state power consumption before and after charging, and calculates the charging power transfer efficiency at the maximum output power of the charger using the electric vehicle simulating device as a load, This is a method of classifying charger operation classes based on standby power consumption and charging power transfer efficiency.

The method for determining the operating level of a charger according to an embodiment of the present invention includes steps S210 to S230.

Step S210 is a step of measuring the power consumed by the charger when the charger is in a standby state. That is, when grid power is supplied to the charger in a state in which a load is not connected to the charger, the power consumed by the charger is measured (or calculated) in the standby state by measuring the voltage/current of the charger input side.

Step S220 is a step of calculating the charging power transfer efficiency of the charger. Connect the load and the charger to start charging. The load is preferably an electric vehicle simulating device capable of controlling the charger according to the charging algorithm of the electric vehicle. Measure the voltage/current of the input side and the output side of the charger, calculate the input power and output power of the charger using the measured values of voltage and current, and calculate the ratio of the output power and the input power when the output power is maximum. Calculate the charging power transfer efficiency of

Step S230 measures (or calculates) the power consumed by the charger when the charger is in the standby state after the end of charging. Since the standby power consumption has already been measured once in step S210, step S230 may be omitted. However, since there may be a difference between the power consumed by the charger when in the standby state before charging starts and the power consumed by the charger when in the standby state after the end of charging, after obtaining the power consumption in the standby state in both steps S210 and S230, In step S240, it is preferable to classify the class by using the average value of the two power consumption values or the maximum value among the two power consumption values. When the class is classified using the maximum value among the two power consumption values, the charger class determined at that time has the meaning of guaranteeing the minimum performance of the charger.

The test configuration used in steps S210 to S230 will be described later with reference to FIGS. 3A to 3D .

For reference, when the charger is in the standby state, the load is not connected to the charger, but the charger is always connected to the power system. In general, a charger has a charger structure with two circuit breakers, a circuit breaker for control and a circuit breaker for charging power supply (charging power supply to the power module in the charger). When there is no load, that is, when there is no charge, what is cut off from the charger is the charging power connected to the power module, and the standby power for control consumed by the controller and the display device is still connected to the grid.

Step S240 is a step for determining the charger operation grade. The operation grade of the charger is determined based on the average value (or maximum value) of power consumption in the standby state and the charging power transfer efficiency of the charger during charging. Charger class classification standards and charger operating class standards that can be used in step S240 will be described later with reference to [Table 1] to [Table 4].

3A to 3D are diagrams illustrating a test configuration for determining an operating grade of a charger according to an embodiment of the present invention. That is, FIGS. 3A to 3D are test configurations that can be used in the method for determining the operating level of the charger described with reference to FIG. 2 .

3A is a test configuration applied to the case of the DC charger 21 . The power meter 100 measures the voltage at a point within d ₁ (eg, 30 cm) from the charger at the input side of the charger receiving power from the system 11 (V11 to V13), and by measuring the current for each phase (A11 to A13) The input power of the charger 21 is calculated. In addition, the power meter 100 measures the voltage at a point within d ₂ (eg, 30 cm) of the DC output side of the charger at the same time (V14), and is supplied to the test load 31 and the buffer battery 32 The output power of the charger 21 is calculated by measuring the total current (A14). The load 31 is an electronic load, and since it must be able to simulate the charging algorithm of an electric vehicle, it must be able to operate in a constant voltage (CV) or constant current (CC: constant current) mode. , or it should be able to change from constant current mode to constant voltage mode.

3B to 3D are test configurations applied to the case of the AC chargers 22 to 24 . For example, if an electric vehicle operates an on-board charger (OBC) to charge a battery, the charging process can be simulated using this test configuration. The AC charger may have a structure of three-phase input-three-phase output 22, three-phase input-single-phase output 23, and single-phase input-single-phase output 24, and according to each structure, voltage/output for input/output The transfer efficiency is calculated by simultaneously measuring the current. In the case of the output of the AC charger (22 to 24), it is necessary to connect the AC load (33 to 35), and in order to evaluate the charging power transfer efficiency at the maximum AC power, the evaluation is performed in the constant resistance mode (CR: Constant Resistance) or the constant current mode. Possible loads (33 to 35) should be provided.

3B is a test configuration applied to the case of the three-phase three-phase AC charger 22 . The power meter 100 measures the voltage at a point within d ₃ (eg, 30 cm) of the charger input side receiving power from the grid 11 (V21 to V23), and measures the current for each phase (A21 to A23) The input power of the charger 22 is calculated. In addition, the power meter 100 measures the voltage at a point within d ₄ (eg, 30 cm) of the AC output side of the charger at the same time (V24 to V26), and measures the total current supplied to the test load 33 (A24 to A26) to calculate the output power of the charger 22.

3C is a test configuration applied in the case of the three-phase-single-phase AC charger 23 . The power meter 100 measures the voltage at a point within d ₅ (eg, 30 cm) of the charger input side receiving power from the grid 11 (V31 to V33), and measures the current for each phase (A31 to A33) The input power of the charger 23 is calculated. In addition, the power meter 100 measures the voltage at a point within d ₆ (eg, 30 cm) of the AC output side of the charger at the same time (V34), and measures the total current supplied to the test load 34 ( A34) The output power of the charger 23 is calculated.

3D is a test configuration applied in the case of single-phase-single-phase AC charger 24 . The power meter 100 measures the voltage (V41) at a point within d ₇ (eg, 30 cm) of the charger input side receiving power from the grid 11 (V41), and measures the current (A41) to the charger (24) Calculate the input power of In addition, the power meter 100 measures the voltage at a point within d ₈ (eg, 30 cm) of the AC output side of the charger at the same time (V42), and measures the total current supplied to the test load 35 ( A42) The output power of the charger 24 is calculated.

A Hall effect sensor may be used at the current measurement points A11 to A14, A21 to A26, A31 to A34, A41 and A42 in FIGS. 3A to 3D . The power meter 100 calculates the charging power transfer efficiency using the input/output power of the DC charger 21 or the AC charger 22 to 24 measured through the test circuit configuration of FIGS. 3A to 3D . In addition, the power meter 100 determines the rating of the charger by measuring the power consumption in the standby state, calculating the transfer efficiency during charging, and measuring the power consumption in the standby state after charging is completed.

[Table 1] to [Table 4] are examples of tables that can be used in step S240 (charger operation grade determination step) in the charger operation grade determination method described with reference to FIG. 2 . [Table 1] to [Table 2] are class tables related to the electrical specifications of the electric vehicle charger, and [Table 3] to [Table 4] are tables for giving the operation grade (performance grade) of the electric vehicle charger. Through [Table 1] to [Table 4], since it is possible to classify the charger according to each class and operation grade (performance grade), it is advantageous in terms of charger management and securing compatibility. [Table 1] is the class classification table of the DC charger, [Table 2] is the class classification table of the AC charger, [Table 3] is the DC charger operation grade standard table, and [Table 4] is the AC charger operation grade standard table.

The electric vehicle charger is divided into a DC charger and an AC charger, and may be classified according to the maximum output power. Even with the same maximum output power, the output voltage and output current specifications may be different. In [Table 1], since the output voltage specification may be different even with the same maximum output power specification, it is divided into a 500V or less charger and a 1500V or less charger in consideration of the existence of 450V class and 1000V class chargers, respectively.

In the case of DC charger, it is first classified into class A / B / C / D / E based on the maximum output power ([Table 1]), and in the case of AC charger, it is divided into class J / K / M / N ( [Table 2]).

Considering that the output voltage and output current specifications may be different even if they have the same maximum output power, [Table 1] divides them into 1 and 2 in the relevant class based on the maximum output voltage. For example, a DC fast charger with a maximum output power of 150 kW corresponds to class C, and if the maximum output voltage of the charger is 850 V, it is classified as a more subdivided class C2.

In a similar way, AC chargers can be classified into classes. However, in most AC chargers, the system voltage corresponding to the charger input is directly related to the output voltage. A subdivision method was adopted depending on whether it was an alternating current or a three-phase alternating current.

Therefore, referring to [Table 2], if an electric vehicle AC charger has a maximum output power specification of 7.7kW and outputs 220V single-phase AC voltage, the corresponding AC charger is class K, and more specifically, class It is a charger corresponding to K1.

On the other hand, after calculating the charging power transfer efficiency of a DC or AC charger, it is possible to compare how much charging power is supplied to the electric vehicle compared to the power the charger receives from the grid based on the ratings in [Table 3] or [Table 4]. have. The charger operation grade determination method according to an embodiment of the present invention uses [Table 3] or [Table 4] to provide an operation grade that can easily determine whether or not the charger is advantageous in terms of operating cost even if the same power is provided to the electric vehicle. given to the charger.

The method for determining the operating grade of a charger according to an embodiment of the present invention obtains an operating grade based on the power consumption in the standby state of the charger, and after obtaining an operating grade based on the charging power transmission efficiency according to the class of the charger, two operating grades It consists of a procedure to determine the lower operating level of the charger as the operating level of the charger. Determining the lower of the two operating grades as the operating grade of the charger is because it is easy to determine whether the charger meets the minimum charger operating grade requirements, and it is reasonable, easy to understand, and reliable from the user's point of view. Because. [Table 1] and [Table 3] are used to describe the method of determining the charger operation grade by way of example. For example, when judging the operating grade for a DC charger with a maximum output of 100kW and a maximum voltage of 450V, when [Table 1] is applied, it can be seen that the charger corresponds to class B (B1 among them). As a result of the test, if the standby power consumption of the charger is 15W and the charging power transfer efficiency at the maximum output is calculated to be 99.86%, when [Table 3] is applied, the charger is operating class 2 based on the standby power consumption It corresponds to a grade, and it corresponds to a grade 3 according to the classification for class B based on the charging power transfer efficiency. Finally, the grade given to the charger is grade 3, which is the lower of the two operating grades. Therefore, the charger is judged as a class 3 charger. Meanwhile, for the AC charger, [Table 2] and [Table 4] are applied to determine the DC charger in the same manner as in the example.

As for the operation grade of the electric vehicle charger, the first grade is the highest and the fifth grade is the lowest, and the lower the grade, the smaller the amount of power delivered to the electric vehicle among the power supplied from the power system. This is because the power used or lost inside the electric vehicle charger is relatively large.

Therefore, by comparing the operating grades of chargers of the same class, it is possible to know which charger has better operating efficiency.

Although the method for determining the operating grade of the charger according to an embodiment of the present invention first presents the grade standard according to the transmission efficiency in the maximum output condition of the electric vehicle charger, the voltage range and the output range used according to the battery voltage of the electric vehicle are actually different. Because it is different, it is also possible to derive the transfer efficiency standard (operating grade determination according to the delivery efficiency standard for each condition) considering this and apply it to the charger operation grade determination.

The transfer efficiency values in the operating grade classification table of [Table 3] and [Table 4] are exemplary, and the scope of the present invention is not limited to the transfer efficiency values of [Table 3] and [Table 4]. A feature of the present invention lies in the technical idea of determining the rating standard based on the charging power transfer efficiency.

In addition, considering that the electric vehicle charger is in a continuous standby state while the system power is supplied or the electric vehicle is in a standby state for a certain period of time or longer after charging is finished, power consumption not directly related to electric vehicle charging occurs. The operating grade standards according to the power consumption in the standby state are also reflected in [Table 3] and [Table 4].

[Table 3] and [Table 4] the reference value for the power consumption of the charger standby state for the DC charger and the AC charger is only an example, the scope of the present invention is the charger standby state power consumption of [Table 3] and [Table 4] Not limited by value. The feature of the present invention lies in the technical idea of determining the rating standard based on the standby power consumption of the charger.

As described above, what the present invention intends to propose is a method for class classification and operation grade determination of electric vehicle chargers and a test configuration for the same, and when the charger is connected with a particular electric vehicle to charge, which charger for a particular electric vehicle It is a method for evaluating the linked charging performance that can compare whether charging is the most efficient and the actual amount of charging/discharging electric energy according to charging is the largest, a test configuration for this, and a power measuring instrument that can perform the above determination method and evaluation method.

4 is a flowchart illustrating a charger-electric vehicle linkage charging performance evaluation method according to an embodiment of the present invention. The charger-electric vehicle linkage charging performance evaluation method according to an embodiment of the present invention includes steps S310 to S350. The evaluation method may be performed according to the test configuration of FIG. 5A or FIG. 5B .

Step S310 is a step of charging the electric vehicle battery. Connect the charger to the electric vehicle and start charging. Charging continues until charging is terminated by the charging control algorithm of the electric vehicle.

Step S320 is a discharging step. When charging is finished, the vehicle (electric vehicle) is left in a room temperature environment for a certain period of time (eg, 12 hours or more) in order to stabilize the vehicle state such as the coolant temperature. This room temperature leaving action is necessary to make the test evaluation conditions constant (the same is true for step S340). Thereafter, using a vehicle dynamometer at room temperature, the vehicle is continuously discharged according to the pre-evaluation pattern until the discharge is cut off in the vehicle. In the electric power evaluation pattern, 'electric power cost' refers to the driving distance [km/kWh] compared to the electric power amount of the electric vehicle.

Step S330 is a step of calculating the amount of input power to the charger through the charging process. When the discharge is finished, the vehicle is left in a room temperature environment to stabilize the vehicle state (eg, left for more than 12 hours). After that, connect the electric vehicle to the charger and start charging. By the electric vehicle charging control algorithm, the instantaneous power [W] data measured at the charger input side and the accumulated charging power (charger input power) [Wh] are calculated and recorded (or automatically saved) during charging until charging is complete.

Step S340 is a step of calculating the amount of discharging power through the discharging process. When charging is finished, the vehicle is left in a room temperature environment to stabilize the vehicle state (eg, left for more than 12 hours). Thereafter, using the vehicle dynamo at room temperature, the instantaneous power [W] and the instantaneous power [W] and the Calculate and record (or automatically save) the accumulated amount of discharge power [Wh].

Step S350 is a step of calculating the charging rate (hereinafter abbreviated as 'linked charging rate') between the charger and the electric vehicle.

The charging performance (linked charging rate) is evaluated by calculating the ratio of the amount of power on the input side of the charger measured in step S330 and the amount of discharging power measured in step S340. Linkage charge rate [%] is calculated by the formula (electric vehicle battery discharge power amount [Wh])/(charger input power amount [Wh])*100. The linked charging rate calculated in this step is defined as the linked charging rate between the corresponding charger and the corresponding electric vehicle, and the result value is stored. For example, the linked charging rate may be stored in the storage unit 140 of the power meter 100 .

Step S360 is a step of comparing the linked charging rate. If the linked charging rate value has been stored in the power meter 100 in the past for the same charger or the same electric vehicle, the linked charging rate may be compared by additionally performing step S360. That is, the linked charging rate between another charger stored in the storage unit 140 of the power meter 100 and the corresponding electric vehicle is compared with the linked charging rate obtained in S350, or through this, the relative high and low of the linked charging rate between the charger and the corresponding electric vehicle to be evaluated can be judged as In addition, by comparing the linked charging rate between the same charger and another electric vehicle stored in the storage unit 140 of the power meter 100 with the linked charging rate obtained in step S350, it is possible to relatively determine which electric vehicle the corresponding charger is more suitable for. .

5A and 5B are diagrams illustrating an embodiment of a test configuration for evaluating charging performance in connection with a specific DC charger and a specific electric vehicle. The configuration of the test environment shown in FIGS. 5A and 5B is, ① by connecting a charger and an electric vehicle, or ② by connecting a charger and an electric vehicle simulating device, to obtain only the linked charging rate between the charger and the electric vehicle, or up to the charger operation grade with the linked charging rate. It can be used for judgment. That is, the test environment configuration shown in FIGS. 5A and 5B is the charger-electric vehicle linked charging performance evaluation method described above with reference to FIG. 4 or the charger operation grade determination and linked charging performance evaluation method to be described later with reference to FIG. All can be used. Although it is shown that the test is performed on the DC charger 21 in FIGS. 5A and 5B , the associated charging rate can be calculated by measuring the charging and discharging power of the electric vehicle battery input side in the same manner as the DC charger for the AC charger. .

5A is a diagram in which the output side of the DC charger 21 is connected to the battery 38 through the internal circuit 37 of the electric vehicle 36 during charging, and FIG. There is a difference in that it is connected to the battery 38 without going through the circuit 37 . The above difference reflects that the internal power transmission path varies depending on the electric vehicle, and other parts are the same.

5a or 5b, the power meter 100 measures the voltage at a point within d ₉ (eg, 30 cm) from the terminal on the input side of the charger 21 receiving power from the system 11 (V51 to V53), by measuring the current for each phase (A51 to A53), the charger 21 input power is calculated. In addition, the power meter 100 measures the voltage at a point within d ₁₀ (eg, 30 cm) from the output side of the charger at the same time (V54), and measures the total current supplied to the electric vehicle 36 (A54) ) Calculate the charger 21 output power. The power meter 100 may calculate the charging power transfer efficiency of the charger by using the current and voltage measured at the input side and the output side of the charger, and may calculate the power consumption in the standby state of the charger before and after charging. And the power meter 100 accumulates the input power and output power of the charger 21 to calculate the charger input power and output power amount. In addition, the power meter 100 is a voltage (V55) and current (V55) and current ( A55) is measured to calculate the charging power and the discharging power of the battery 38, and by accumulating each instantaneous power, the charging power and the discharging power are calculated. The power meter 100 calculates the charger-electric vehicle linkage charge rate using the charger input power amount and the battery 38 discharge power amount.

6 is a flowchart illustrating a method for determining a charger operation grade and evaluating a connected charging performance according to an embodiment of the present invention. The method includes steps S410 to S440, and detailed steps of steps S410 to S430 will be described later with reference to FIGS. 7A to 7C.

A test environment is configured as shown in FIG. 5A or FIG. 5B, and the process proceeds from step S410. The charger operation grade determination and linked charging performance evaluation method according to an embodiment of the present invention proceeds in the order of charge-discharge-charge-discharge. The reason that the method proceeds from charging is that the state of the battery at the start of the test is an arbitrary state that is not standardized. will be considered In addition, the method is designed to simultaneously obtain the evaluation result of the linked charging performance and the operation grade determination result of the charger twice while operating the dynamometer at least (two times). The method can secure the reliability of the determination result through two times of the charger operation grade determination. In addition, the method can obtain a grade determination result reflecting the charging control algorithm of the vehicle and other vehicle conditions by conducting a test by connecting an actual electric vehicle to the charger. It also has the meaning that it can be mutually verified through comparison with the operating grade.

Step S410 is the first determination step of the charger operation grade. In the standby state where the electric vehicle is not connected to the charger, the power consumption of the charger is measured (calculated), and the charging power transfer efficiency value at the maximum output power of the charger is obtained through the charging process. And, based on the charging power transfer efficiency value of the charger at the standby state consumption power and the maximum output power value, the charger operation grade is primarily determined.

Step S420 is a secondary determination step of calculating the amount of input power of the charger and the charger operating grade. First, the vehicle is left in a room temperature environment for a certain period of time to stabilize the vehicle state. Measure the power consumed by the charger while the charger is in standby state. When the vehicle state is stabilized, the vehicle continuously discharges until the discharge is cut off according to the pre-evaluation pattern using the vehicle dynamometer at room temperature. When discharging is finished, the vehicle is left in the room temperature environment for a certain period of time to stabilize the vehicle state, and then the voltage/current at the input/output side of the charger and the input side of the electric vehicle battery until charging is terminated by the electric vehicle charging control algorithm. Through measurement, instantaneous power data and accumulated charging power during charging (charger input power) are calculated. Using the instantaneous power data of the input/output side of the charger, the charging power transfer efficiency value of the charger when the output power is maximum is obtained. And, based on the charging power transfer efficiency value of the charger at the standby state consumption power and the maximum output power value, the charger operation grade is determined secondarily.

Step S430 is a step of calculating the amount of discharging power of the battery and the charger-electric vehicle linkage charging rate. The vehicle condition is stabilized by leaving the vehicle in a room temperature environment for a certain period of time. Thereafter, the amount of discharging power of the electric vehicle battery is calculated through the discharging process. A linked charging rate is calculated using the amount of input power of the charger calculated in step S420 and the amount of discharging power. The linked charging rate calculated in this step is defined as the linked charging rate between the corresponding charger and the corresponding electric vehicle, and the result value is stored. For example, the linked charging rate may be stored in the storage unit 140 of the power meter 100 .

Step S440 is a step of comparing the linked charging rate. If the linked charging rate value has been stored in the power meter 100 in the past for the same charger or the same electric vehicle, the linked charging rate may be compared by additionally performing step S440. That is, the linked charging rate between another charger and the corresponding electric vehicle stored in the storage unit 140 of the power meter 100 is compared with the linked charging rate obtained in S430, or the high and low of the linked charging rate between the evaluation target charger and the corresponding electric vehicle is relative can be judged as In addition, by comparing the linked charging rate between the same charger and another electric vehicle stored in the storage unit 140 of the power meter 100 with the linked charging rate obtained in step S430, it is possible to relatively determine which electric vehicle the corresponding charger is more suitable for. .

7A to 7C are detailed flowcharts of a method for determining a charger operating grade and evaluating a linked charging performance according to an embodiment of the present invention.

7A to 7C are diagrams illustrating detailed steps and flows included in each of steps S410 to S430 of the method for determining the operating grade of the charger and evaluating the linked charging performance described above with reference to FIG. 6 .

Step S411 is a step of measuring the standby power consumption of the charger. In the standby state when the electric vehicle is not connected to the charger, the power consumption of the charger is measured (calculated).

Step S412 is a step of calculating the charging power transfer efficiency of the charger through charging. Connect the charger to the electric vehicle and start charging. Measure the charger input/output power and battery input power while charging. Using the charger input power and charger output power measured while charging, the charging power transfer efficiency is continuously measured (calculated), and the charging power transfer efficiency is calculated at the maximum value of the measured output power when charging the electric vehicle. Charging continues until charging is terminated by the charging control algorithm of the electric vehicle.

Step S413 is a step of determining the charger operation grade. Based on the standby state consumption power obtained in step S411 and the charger charging power transfer efficiency value at the maximum output power obtained in step S412, the charger operation grade is first determined.

Step S421 is a step of stabilizing the vehicle state. When charging is finished, the vehicle is left in a room temperature environment for a predetermined period of time (eg, 12 hours or more) in order to stabilize the vehicle state such as the coolant temperature. This room temperature leaving action is necessary to make the test evaluation conditions constant (the room temperature leaving action in steps S424 and S431 also has the same effect). When step S421 is finished, step S423 is performed.

Step S422 is a step of measuring power consumed by the charger while the charger is in a standby state. Step S422 may be performed after charging or before charging. That is, the power consumed by the charger is measured (or calculated) in the standby state by measuring the voltage/current at the input side of the charger in a state in which a load is not connected to the charger. Step S422 may be performed in parallel with steps S421, S423, and S424. Step S422 may be omitted. In this case, the standby power consumption value of the charger used when determining the charger operation grade in step S426 becomes the power consumption value measured in step S411.

Step S423 is a discharging step. When the vehicle state is stabilized, the vehicle continuously discharges until the discharge is cut off according to the pre-evaluation pattern using the vehicle dynamometer at room temperature.

Step S424 is a step for stabilizing the vehicle state. When the discharge is finished, the vehicle is left in a room temperature environment for a predetermined time (eg, 12 hours or more) in order to stabilize the vehicle state.

Step S425 is a step of calculating the charging power transfer efficiency and the amount of input power to the charger through the charging process. When the vehicle's condition is stabilized, the electric vehicle starts charging again. Instantaneous power [W] data and accumulated charging power during charging (charger input power) [Wh] is calculated and recorded (or automatically saved). Based on the data, the charging power transfer efficiency at the maximum output of the charger is obtained.

Step S426 is a step of determining the charger operation grade. Based on the standby state consumption power obtained in step S422 and the charging power transfer efficiency value of the charger at the maximum output obtained in step S412, the charger operation grade is secondarily determined. When step S422 is omitted as described above, the standby power consumption value obtained in step S411 is used for rating determination. As another embodiment, the average value or the maximum value of the standby state power consumption obtained in step S411 and the standby state consumption power obtained in step S422 may be used in the second determination of the charger operation grade. In addition, while the standby power consumption value obtained in step S411 is used as it is in the second determination, the standby power consumption value obtained in step S422 may be used only as a reference value.

Step S431 is a step for stabilizing the vehicle state. When charging is finished, the vehicle is left in a room temperature environment for a certain period of time (eg, 12 hours or more) in order to stabilize the vehicle state.

Step S432 is a step of calculating the amount of discharging power through the discharging process. At room temperature, using the vehicle dynamometer, the vehicle continuously discharges according to the pre-evaluation pattern until the discharge is cut off. Calculate (Wh) and record (or automatically store).

Step S433 is a step of calculating the linked charging rate between the charger and the electric vehicle. The connected charging rate is calculated using the amount of input power of the charger calculated in step S425 and the amount of discharging power measured in step S432. Linkage charge rate [%] is calculated by the formula (electric vehicle battery discharge power amount [Wh])/(charger input power amount [Wh])*100. The linked charging rate calculated in this step is defined as the linked charging rate between the corresponding charger and the corresponding electric vehicle, and the result value is stored. For example, the linked charging rate may be stored in the storage unit 140 of the power meter 100 .

After step S433, step S440 may be additionally performed. Step S440 has been described above with reference to FIG. 6 .

For reference, the components according to the embodiment of the present invention may be implemented in the form of software or hardware such as a field programmable gate array (FPGA) or an application specific integrated circuit (ASIC), and may perform predetermined roles.

However, 'components' are not limited to software or hardware, and each component may be configured to reside in an addressable storage medium or to reproduce one or more processors.

Thus, as an example, a component includes components such as software components, object-oriented software components, class components, and task components, and processes, functions, properties, procedures, sub It includes routines, segments of program code, drivers, firmware, microcode, circuits, data, databases, data structures, tables, arrays and variables.

Components and functions provided within the components may be combined into a smaller number of components or further divided into additional components.

At this time, it will be understood that each block of the flowchart diagrams and combinations of the flowchart diagrams may be performed by computer program instructions. These computer program instructions may be embodied in a processor of a general purpose computer, special purpose computer, or other programmable data processing equipment, such that the instructions performed by the processor of the computer or other programmable data processing equipment are not described in the flowchart block(s). It creates a means to perform functions. These computer program instructions may be stored in a computer readable memory or using a computer, which may be directed to a computer or other programmable data processing equipment to implement a function in a particular manner, thereby enabling the computer to use the computer or to be computer readable. It is also possible that the instructions stored in the memory produce an article of manufacture containing instruction means for performing the function described in the flowchart block(s). The computer program instructions may also be mounted on a computer or other programmable data processing equipment, such that a series of operational steps are performed on the computer or other programmable data processing equipment to create a computer-executed process to create a computer or other programmable data processing equipment. It is also possible that instructions for performing the processing equipment provide steps for performing the functions described in the flowchart block(s).

Additionally, each block may represent a module, segment, or portion of code that includes one or more executable instructions for executing specified logical function(s). It should also be noted that in some alternative implementations it is also possible for the functions recited in the blocks to occur out of order. For example, it is possible that two blocks shown in succession are actually performed substantially simultaneously, or that the blocks are sometimes performed in the reverse order according to the corresponding function.

At this time, the term '~ unit' used in this embodiment means software or hardware components such as FPGA or ASIC, and '~ unit' performs certain roles. However, '-part' is not limited to software or hardware. '~unit' may be configured to reside on an addressable storage medium or may be configured to refresh one or more processors. Thus, as an example, '~' denotes components such as software components, object-oriented software components, class components, and task components, and processes, functions, properties, and procedures. , subroutines, segments of program code, drivers, firmware, microcode, circuitry, data, databases, data structures, tables, arrays, and variables. The functions provided in the components and '~ units' may be combined into a smaller number of components and '~ units' or further separated into additional components and '~ units'. In addition, components and '~ units' may be implemented to play one or more CPUs in a device or secure multimedia card.

The above-described charger operation grade determination method, charger-electric vehicle linked charging performance evaluation method, and charger operation grade determination and linked charging performance evaluation method have been described with reference to the flowchart presented in the drawings. For simplicity, the method has been shown and described as a series of blocks, but the invention is not limited to the order of the blocks, and some blocks may occur with other blocks in a different order or at the same time as shown and described herein. Also, various other branches, flow paths, and orders of blocks may be implemented that achieve the same or similar result. Also, not all illustrated blocks may be required for implementation of the methods described herein.

In the above, the configuration of the present invention has been described in detail with reference to the accompanying drawings, but this is merely an example, and those skilled in the art to which the present invention pertains may make various modifications and changes within the scope of the technical spirit of the present invention. Of course, this is possible. Therefore, the protection scope of the present invention should not be limited to the above-described embodiments and should be defined by the description of the following claims.

11: grid or distribution box
21: DC charger
22: three-phase three-phase AC charger
23: 3-phase-single-phase AC charger
24: single-phase to single-phase AC charger
31: load (electronic load)
32: battery for buffer
33: load (AC load)
34: load (AC load)
35: load (AC load)
100: power meter
110: measurement unit
120: Charger operating class determination unit
130: Linked charging performance evaluation unit
140: storage

Claims (10)

'Standby power consumption measurement step before charging' of measuring the power consumed by the charger when the electric vehicle charger is in the standby state;
connecting the charger and the load to start charging, and calculating the charging power transfer efficiency, which is the ratio of the output power to the input power of the charger when the output power of the charger is maximum in the charging process;
'Standby power consumption measurement step after charging' of measuring the power consumed by the charger when the charger is in a standby state after charging is finished; and
Classifying the class of the charger according to the maximum output power of the charger, and based on the class, measured in the 'standby state power consumption measurement step before charging' and the 'standby state power consumption measurement step after charging', the determining a charger operation grade based on an average value of power consumed by the charger and the charging power transfer efficiency;
including,
The load is
Replicating the charging algorithm of an electric vehicle
A method of determining the operating grade of an electric vehicle charger. According to claim 1,
The charger is a DC charger,
The load may operate in either a constant voltage mode or a constant current mode during the charging process,
How to determine the operating grade of an electric vehicle charger. According to claim 1,
The charger is an AC charger,
The load can operate in any of a constant resistance mode and a constant current mode during the charging process,
How to determine the operating grade of an electric vehicle charger. According to claim 1, wherein the step of determining the charger operating grade,
Determining the lower operating grade among the charger operating grade determined based on the average value of power consumed in the charger and the charger operating grade determined based on the charging power transfer efficiency as the final operating grade of the charger
A method of determining the operating grade of an electric vehicle charger. connecting the charger and the electric vehicle and charging the battery of the electric vehicle until charging is terminated by a charging control algorithm of the electric vehicle;
leaving the electric vehicle for a certain period of time to stabilize the state of the electric vehicle, and discharging the electric vehicle according to a predetermined pre-evaluation pattern until the electric vehicle stops discharging;
connecting the electric vehicle to the charger, starting charging, and accumulating the instantaneous power measured at the input side of the charger to calculate the amount of input power to the charger;
leaving the electric vehicle for a certain period of time to stabilize the state of the electric vehicle, discharging the electric vehicle according to a predetermined pre-evaluation pattern until the electric vehicle stops discharging, and calculating the amount of discharging power of the battery of the electric vehicle; and
calculating a charger-electric vehicle linkage charging rate, which is a ratio of the amount of discharging power and the amount of input power to the charger;
A charger-electric vehicle linkage charging performance evaluation method comprising a. After measuring the standby state power consumption of the electric vehicle charger, connecting the charger and the electric vehicle, and calculating the charging power transfer efficiency of the charger through the process of charging the electric vehicle battery, the standby state consumption power and the Charger operation grade primary determination step of determining the operation grade of the charger based on the charging power transfer efficiency;
Measure the standby power consumption of the charger again, connect the charger and the electric vehicle, calculate the amount of input power to the charger through the process of charging the electric vehicle battery, and After calculating the charging power transfer efficiency again, the charger input power amount calculation and charger operation class secondary determination step for determining the operation grade of the charger based on the re-measured standby state consumption power and the re-calculated charging power transfer efficiency ;
Calculating the amount of discharging power of the battery of the electric vehicle through the discharging process of the electric vehicle battery, calculating the ratio of the amount of discharging power and the input power of the charger to calculate the linked charging rate between the charger and the electric vehicle step; and
determining suitability of the charger for the electric vehicle by comparing the linked charging rate between the electric vehicle and the other electric vehicle and the charger with the linked charging rate between the charger and the electric vehicle;
A method for determining the operating grade of an electric vehicle charger and evaluating the charger-electric vehicle linkage charging performance, including. The method of claim 6, wherein the first determination step of the charger operation grade and the calculation of the charger input power amount and the second determination step of the charger operation grade,
Charging of the battery proceeds according to the charging control algorithm of the electric vehicle
A method for determining the operating grade of an electric vehicle charger and evaluating the charger-electric vehicle linkage charging performance. a measuring unit measuring the voltage and current of the input side and the output side of the electric vehicle charger, and calculating standby state consumption power, input power, and output power of the charger by using the measured values of the voltage and current; and
Classifying the class of the charger according to the maximum output power of the charger, calculating the ratio of the maximum output power and the input power to obtain the charging power transfer efficiency, based on the class, the standby state consumption power and the charging power Charger operation grade judgment unit that judges the charger operation grade based on the transmission efficiency
A power meter for determining the operating class of the charger, including. a measuring unit that measures the voltage and current of the input side of the electric vehicle charger and the output side of the electric vehicle battery, and calculates the amount of input power of the charger and the amount of discharge power of the battery by using the measured values of the voltage and current;
a linked charging performance evaluation unit for calculating a linked charging rate between a charger and an electric vehicle based on the amount of input power and the amount of discharging power; and
A storage unit for storing the linked charging rate calculated by the linked charging performance evaluation unit
including,
The linked charging performance evaluation unit,
Comparing and evaluating the linked charging rate for each electric vehicle of the charger based on the stored linked charging rate of the charger
A power meter for evaluation of charging performance in connection with in-charger-electric vehicles. Measuring the voltage and current of each input side and output side of the electric vehicle charger and the electric vehicle battery, and using the measured values of the voltage and current, the standby state consumption power of the charger, input power, output power, input power amount and the battery a measuring unit that calculates the amount of discharge power of
Classifying the class of the charger according to the maximum output power of the charger, calculating the ratio of the maximum output power and the input power to obtain the charging power transfer efficiency, based on the class, the standby state consumption power and the charging power Charger operation grade determination unit for determining the charger operation grade based on the transmission efficiency; and
Including;
A power meter for the evaluation of charger operation grade and the evaluation of connected charging performance.

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