DE102019217450A1 - Charging station and method for charging a consumer with load sharing - Google Patents

Abstract

The invention relates to a charging station (1) with at least one charging point (2.1-2.4). The charging station (1) has at least one rectifier (3) which rectifies an alternating voltage to a first direct voltage (U1); at least one first DC voltage converter (4.1, 4.2), which converts the first DC voltage (U1) to a second DC voltage (U2.1, U2.2), with between the first DC voltage (U1) and the second DC voltage (U2.1, U2 .2) there is electrical isolation; and a plurality of second DC voltage converters (5.1-5.4), which are connected in parallel to the at least one first DC voltage converter (4.1, 4.2) and each converts the second DC voltage (U2.1, U2.2) to a third DC voltage (U3.1 - U3.4), with no potential separation between the second DC voltage (U2.1, U2.2) and the third DC voltage (U3.1 - U3.4), and the third DC voltage (U3.1 - U3. 4) at which at least one charging point (2.1 - 2.4) can be tapped. The invention also relates to a method for charging a consumer at a charging point (2.1-2.4) of a charging station (1).

Description

The present invention relates to a charging station with at least one charging point. The charging point can be a charging plug that can be connected to a consumer, such as an electric vehicle. The present invention also relates to a method for charging a consumer at a charging point of a charging station.

In the future, the charging of battery-operated vehicles will move towards ever larger charging capacities of, for example, more than 150 kW. This applies in particular to the area of local public transport and heavy goods traffic. The charging stations are becoming more and more expensive due to today's construction principle, since all components have to be designed for a single charging point. This is particularly important when the batteries are charged in the range of more than 80% of the maximum charge capacity. From this point on, the required charging power drops sharply, as the battery cells can consume significantly less power. This means that the expensive components of the charging station are no longer fully utilized. It is generally desirable to reduce the costs per charging point.

So far, there have been two main approaches to reducing the costs per charging point. According to one in the 2 The first approach shown is a DC bus 600 used at which all charging points 200 through separate DC voltage converters 400 are connected, each one from a rectifier 300 convert rectified voltage. It's just the one central rectifier 300 available, and this can be at the different charging points 200 the maximum charging power of the DC / DC converter 400 as long as the maximum output power of the central rectifier 300 is not exceeded. Any DC / DC converter 400 has electrical isolation and a large control range.

According to one in the 3rd The second approach shown can increase the charging power of several DC-DC converters 400 through a relay arrangement 700 to different charging points 200 be switched. This method is very complex during operation because the DC voltage converter 400 must be brought to the same voltage level when connecting another converter in order to avoid equalizing currents.

There is a need for a charging station and a method for charging a consumer at a charging point of a charging station that can overcome these disadvantages. This need can be met by the subject matter of the independent claims. The present invention is further developed in accordance with the dependent claims.

A first aspect of the invention relates to a charging station with at least one charging point. The charging station has the following: at least one rectifier, which rectifies an alternating voltage to a first direct voltage; at least one first DC voltage converter which converts the first DC voltage to a second DC voltage, a potential separation being provided between the first DC voltage and the second DC voltage; and a plurality of second DC voltage converters, which are connected in parallel to the at least one first DC voltage converter and each convert the second DC voltage to a third DC voltage, there being no potential separation between the second DC voltage and the third DC voltage. The third DC voltage can be tapped off at the at least one charging point.

In the context of the present invention, the term “no potential separation” can include a situation in which two voltages define potentials that relate to the same ground. The term “a potential separation” can therefore contain a situation in which two voltages define potentials that relate to different, mutually independent masses.

The DC / DC converters are divided into multiple components that can be switched in parallel: The at least one first DC / DC converter is used for electrical isolation and can consist of several DC-AC-DC converters that can be switched in parallel, which are connected to a first DC voltage bus (DC -Bus) work. The first DC voltage converter or converters can have a relatively small control range. The output of each individual first DC / DC converter can be determined from the range of components that are optimally available in terms of costs and can be in the range of approximately 20 kW to 60 kW. The first direct voltage converter or converters can in turn provide a second direct voltage bus (DC bus) on which the second direct voltage converters operate. This can involve several DC-DC converters that can be switched in parallel without electrical isolation, which can have a large control range, and they can be connected to the first DC voltage bus. The second DC / DC converter can take over the charging management of the vehicle battery and be able to control the current flow to the charging points using software. The electronic components of such a second DC voltage converter are without potential separation cheaper than a circuit breaker (for example a DC contactor) for load distribution in the required voltage and power range.

In one embodiment, a plurality of first DC voltage converters are provided, which are connected in parallel to the rectifier and each feed the second DC voltage to at least some of the second DC voltage converters.

In one embodiment, the rectifier outputs the first DC voltage via a power factor correction filter to a first DC voltage bus, which is accessed by the at least one first DC voltage converter.

In one embodiment, the at least one first DC voltage converter outputs the second DC voltage to a second DC voltage bus, which the second DC voltage converters access.

In one embodiment, the charging station also has a control device that is configured to communicate with a communication device of a consumer connected to the at least one charging point, which provides the control device with a setpoint for the third DC voltage, a power required by the consumer and / or a fill level transmitted to a battery of the consumer, the control device being configured to derive a power required for charging the consumer from the fill level. The control device regulates the second direct voltage output by the at least one first direct voltage converter and / or the third direct voltage output by the second direct voltage converters in order to achieve the setpoint value for the third direct voltage and / or the required power.

The second DC voltage converters without potential separation of the charging points can be controlled, for example, by the control device in the form of a hardware controller in order to configure the maximum charging power. The hardware controller can communicate with the communication device in the form of a charging controller for the individual charging points and receive information from there as to which maximum charging power is currently still required at the charging point, whereupon it configures the second DC-DC converter of the charging points accordingly.

In one embodiment, the second DC voltage converters each have an insulation monitor.

A second aspect of the invention relates to a method for charging a consumer at a charging point of a charging station, the charging station having the following: at least one rectifier which rectifies an AC voltage to a first DC voltage; at least one first DC voltage converter which converts the first DC voltage to a second DC voltage, a potential separation being provided between the first DC voltage and the second DC voltage; and a plurality of second DC voltage converters, which are connected in parallel to the at least one first DC voltage converter and each convert the second DC voltage to a third DC voltage, with no potential separation between the second DC voltage and the third DC voltage, and the third DC voltage at the at least a charging point can be tapped. The method has the following steps: Acquisition of a setpoint value for the third DC voltage ( U3.1 - U3.4 ), a required power for charging the consumer or a fill level of a battery of the consumer at the charging point, wherein a required power for charging the consumer is derived from the fill level; and regulating the second direct voltage output by the at least one first direct voltage converter and / or the third direct voltage output by the second direct voltage converters in order to achieve the setpoint value for the third direct voltage and / or the required power.

For example, the required power can be reduced while the charging process is in progress if the fill level of the battery exceeds a threshold value, for example 70% or 80% SoC.

The invention enables the scalable modular structure of charging stations or charging columns and the simple dynamic assignment of maximum performance data to individual charging points. This leads to considerable cost savings when setting up a charging infrastructure with a larger number of charging points. The advantage of the solution is achieved through a modular concept that is consistently used at all levels, which increases the number of modules used and thus reduces the price per unit. In addition, a range of components can be accessed, which is optimized in price and production for smaller services of the mass market and thus offers further cost advantages.

In addition, a dynamic assignment of upper performance limits to individual charging points enables the maximum overall performance of the charging infrastructure to be designed to be lower, since batteries in the upper fill level range (e.g. more than 80% state-of-charge (SoC)) are less Can consume power, but still occupy the charging point. The time to reach 100% SoC is roughly the same as to reach 80% SoC.

For fleet solutions, there is the advantage that several vehicles can be charged at the same time, but the charging power can be dynamically distributed to the charging points by means of load management, taking into account the scalable hardware components.

Overall, the invention enables the charging infrastructure to be produced more cheaply, since the dimensions of the hardware components per charging point are reduced. In addition, a scalability is achieved which simplifies the expansion of existing systems, since only the required hardware components have to be added depending on the requirements.

• 1 zeigt ein Ersatzschaltbild einer Ladestation gemäß einem Ausführungsbeispiel;
• 2 zeigt ein Ersatzschaltbild einer Ladestation gemäß dem Stand der Technik; und
• 3 zeigt ein Ersatzschaltbild einer Ladestation gemäß dem Stand der Technik.

The aspects defined above and further aspects of the present invention emerge from the exemplary embodiments described below. The invention is described in more detail below with reference to the exemplary embodiments, to which the invention is not limited, however.

• 1 shows an equivalent circuit diagram of a charging station according to an embodiment;
• 2 shows an equivalent circuit diagram of a charging station according to the prior art; and
• 3rd shows an equivalent circuit diagram of a charging station according to the prior art.

The drawings are shown schematically. It should be noted that similar or identical elements are provided with the same reference symbols in different figures.

1 shows an equivalent circuit diagram of a charging station 1 according to an embodiment with four charging points 2.1 , 2.2 , 2.3 , 2.4 . The number of charging points 2.1 , 2.2 , 2.3 , 2.4 is not limited to four. Every charging point 2.1 , 2.2 , 2.3 , 2.4 can be a charging plug that can be connected to a consumer, such as an electric vehicle. The charging station 1 has a rectifier 3rd , of an alternating voltage with three phases L1 , L2 , L3 to a first DC voltage U1 rectifies. The charging station 1 has two first DC voltage converters in the illustrated embodiment 4.1 , 4.2 each the first DC voltage U1 to a second DC voltage U2.1 or. U2.2 convert, with between the first DC voltage U1 and the second DC voltage (s) U2.1 , U2.2 electrical isolation is available. The first two DC converters 4.1 , 4.2 are in parallel at one output of the rectifier 3rd connected. The number of first DC / DC converters 4.1 , 4.2 is not limited to two.

The charging station 1 further has a plurality of second DC-DC converters 5.1 , 5.2 , 5.3 , 5.4 that are connected in parallel to the outputs of the first two DC voltage converters 4.1 , 4.2 are connected. The first two DC converters 4.1 , 4.2 therefore lead the second DC voltage U2.1 or. U2.2 each to all second DC voltage converters 5.1 , 5.2 , 5.3 , 5.4 to. As well as the number of charging points 2.1 , 2.2 , 2.3 , 2.4 is the number of corresponding second DC voltage converters 5.1 , 5.2 , 5.3 , 5.4 not limited to two.

The second DC / DC converter 5.1 , 5.2 , 5.3 , 5.4 convert the second DC voltage U2.1 , U2.2 to a third DC voltage U3.1 , U3.2 , U3.3 , U3.4 , with between the second DC voltage U2.1 , U2.2 and the third DC voltage U3.1 , U3.2 , U3.3 , U3.4 there is no potential separation and the third DC voltage U3.1 , U3.2 , U3.3 , U3.4 at the respective charging points 2.1 , 2.2 , 2.4 , 2.4 can be tapped. Each from the second DC / DC converter 5.1 , 5.2 , 5.3 , 5.4 third DC voltages output U3.1 , U3.2 , U3.3 , U3.4 as well as each of the first DC voltage converters 4.1 , 4.2 second direct voltages output U2.1 or. U2.2 each have a potential that points to the same ground M. is related.

The second DC / DC converter 5.1 , 5.2 , 5.3 , 5.4 each have an insulation monitor.

The first DC / DC converters 4.1 , 4.2 have a relatively small control range. The performance of each individual first DC voltage converter 4.1 , 4.2 can be in the range of about 20 kW to 60 kW. The second DC / DC converter 5.1 , 5.2 , 5.3 , 5.4 can have a larger control range.

According to the 2 leads the output of every second DC / DC converter 5.1 , 5.2 , 5.3 , 5.4 to its own charging point 2.1 , 2.2 , 2.3 , 2.4 , ie the respective third DC voltages U3.1 , U3.2 , U3.3 , U3.4 are from the second DC / DC converters 5.1 , 5.2 , 5.3 , 5.4 to different charging points 2.1 , 2.2 , 2.3 , 2.4 fed.

The rectifier 3rd gives the first DC voltage U1 via a power factor correction filter to a first DC bus 6th on which the first two DC voltage converters 4.1 , 4.2 access.

The first two DC converters 4.1 , 4.2 give the second DC voltage U2.1 or. U2.2 to a second DC bus 7th from which the second DC / DC converter 5.1 , 5.2 , 5.3 , 5.4 access. Due to the potential separation within the first DC voltage converter 4.1 , 4.2 are the second DC / DC converters 5.1 , 5.2 , 5.3 , 5.4 from the inverter 3rd galvanically isolated.

The charging station 1 also has a control device 8th in the form of a hardware controller that is configured to connect to a communication device such as a communication controller (not shown) at the at least one charging point 2.1 , 2.2 , 2.3 , 2.4 connected consumer (not shown) to communicate to the control device 8th a power required by the consumer and / or a target value for the third DC voltage U3.1 , U3.2 , U3.3 , U3.4 transmitted. The control device 8th regulates the at least one first DC voltage converter 4.1 , 4.2 second DC voltage output U2.1 , U2.2 and / or from the second DC / DC converters 5.1 , 5.2 , 5.3 , 5.4 third DC voltage output U3.1 , U3.2 , U3.3 , U3.4 to get the required power and / or the setpoint for the third DC voltage U3.1 , U3.2 , U3.3 , U3.4 provide. The control device 8th can be a first hardware controller 81 with a first regulation range, which is the second DC voltage U2.1 , U2.2 regulates, and a second hardware controller 82 with a second control range, which is the third DC voltage U3.1 , U3.2 , U3.3 , U3.4 regulates.

The second hardware controller 82 can preferably be integrated into individual, independent hardware controllers 82, 82.2, 82.3, 82.4 for the corresponding charging points 2.1 , 2.2 , 2.3 , 2.4 be divided.

Every charging point 2.1 , 2.2 , 2.3 , 2.4 can be an independent voltage U3.1 , U3.2 , U3.3 or. U3.4 . generate and deliver an individual service accordingly. The desired voltage or power at the charging point 2.1 , 2.2 , 2.3 , 2.4 is transmitted from the corresponding consumers via the communications controller of the consumer to the second hardware controller (s) 82 (or 82.1-82.4). This (s) controls the corresponding second DC / DC converter 5.1 , 5.2 , 5.3 , 5.4 accordingly. In order to ensure that there is sufficient power in the overall system, the second hardware controller (s) 82 (or 82.1 - 82.4) give the requirements for the first hardware controller 81 further, which ensures that there is enough power for all charging points 2.1 , 2.2 , 2.3 , 2.4 is available. Is this not possible due to bottlenecks (e.g. if the rectifier is overloaded 3rd ), there will be an individual power reduction at the charging points 2.1 , 2.2 , 2.3 , 2.4 from the first hardware controller 81 sent as a request to the second hardware controller (s) 82 (or 82.1 - 82.4).

In one embodiment, the control device 8th have a recording device (not shown) that shows the level of a battery at the charging point 2.1 , 2.2 , 2.3 , 2.4 loads to be charged. The control device can be configured to derive the power required to charge the consumer from the fill level. In a further embodiment, the control device 8th a detection device, the a voltage of the battery of the at the charging point 2.1 , 2.2 , 2.3 , 2.4 recorded consumer to be charged. The control device 8th can derive the power required to charge the consumer from this.

In this method, a required power for charging the consumer and / or a fill level of a battery of the consumer at the charging point 2.1 , 2.2 , 2.3 , 2.4 permanently recorded, with the required power for charging the consumer being derived from the level.

For example, the charging power through the second DC voltage converter 5.1 , 5.2 , 5.3 , 5.4 can be reduced during the ongoing charging process if the battery level is at the corresponding charging point 2.1 , 2.2 , 2.3 , 2.4 connected consumer exceeds a threshold value, for example 70% or 80% SoC.

The invention enables the scalable modular construction of the charging station 1 or of charging stations as well as the simple dynamic assignment of maximum performance data to individual charging points 2.1 , 2.2 , 2.3 , 2.4 . This leads to considerable cost savings when setting up a charging infrastructure with a larger number of charging points 2.1 , 2.2 , 2.3 , 2.4 . The advantage of the solution is achieved through a modular concept that is consistently used at all levels, which increases the number of modules used and thus reduces the price per unit. In addition, a range of components can be accessed, which is optimized in price and production for smaller services of the mass market and thus offers further cost advantages.

In addition, it enables a dynamic assignment of upper performance limits to individual charging points 2.1 , 2.2 , 2.3 , 2.4 that the maximum overall power of the charging infrastructure can be designed to be lower, since batteries in the upper fill level range (e.g. more than 80% state-of-charge (SoC)) can consume less power, but the charging point 2.1 , 2.2 , 2.3 , 2.4 continue to occupy. The time to reach 100% SoC is roughly the same as to reach 80% SoC.

For fleet solutions there is the advantage that several vehicles can be charged at the same time, but the charging power is dynamically applied to the charging points by means of load management, taking into account the scalable hardware components 2.1 , 2.2 , 2.3 , 2.4 can be distributed.

Overall, the invention enables the charging infrastructure to be produced more cheaply, since the dimensioning of the hardware components per charging point 2.1 , 2.2 , 2.3 , 2.4 sinks. In addition, a scalability is achieved which simplifies the expansion of existing systems, since only the required hardware components have to be added depending on the requirements.

It should be noted that the term “having” does not exclude other elements or steps. Elements that are described in connection with various embodiments can also be combined. It should also be noted that any reference signs in the claims should not be construed as reflecting the scope of the claims.

List of reference symbols

1

Charging station

2.1

Charging point

2.2

Charging point

2.3

Charging point

2.4

Charging point

3

Rectifier

4.1

first DC / DC converter

4.2

first DC / DC converter

5.1

second DC / DC converter

5.2

second DC / DC converter

5.3

second DC / DC converter

5.4

second DC / DC converter

6th

first DC bus

7th

second DC bus

8th

Control device

81

first hardware controller

82

second hardware controller

L1

AC phase

L2

AC phase

L3

AC phase

U1

first DC voltage

U2.1

second DC voltage

U2.2

second DC voltage

U3.1

third DC voltage

U3.2

third DC voltage

U3.3

third DC voltage

U3.4

third DC voltage

M.

Dimensions

200

Charging point

300

Rectifier

400

DC-DC converter

600

DC bus

700

Relay arrangement

Claims (8)

Charging station (1) with at least one charging point (2.1 - 2.4), the charging station (1) having the following: at least one rectifier (3) which rectifies an alternating voltage to a first direct voltage (U1); at least one first DC voltage converter (4.1, 4.2), which converts the first DC voltage (U1) to a second DC voltage (U2.1, U2.2), with between the first DC voltage (U1) and the second DC voltage (U2.1, U2 .2) there is electrical isolation; and a plurality of second DC voltage converters (5.1-5.4) which are connected in parallel to the at least one first DC voltage converter (4.1, 4.2) and each converts the second DC voltage (U2.1, U2.2) to a third DC voltage (U3.1-U3 .4), with no potential separation between the second direct voltage (U2.1, U2.2) and the third direct voltage (U3.1 - U3.4), and the third direct voltage (U3.1 - U3.4 ) at which at least one charging point (2.1 - 2.4) can be tapped. Charging station (1) according to the preceding claim, wherein a plurality of first DC voltage converters (4.1, 4.2) are provided, which are connected in parallel to the rectifier (3) and the second DC voltage (U2.1, U2.2) each at least to one Feed part of the second DC voltage converter (5.1 - 5.4). Charging station (1) according to one of the preceding claims, wherein the rectifier (3) outputs the first DC voltage (U1) via a power factor correction filter to a first DC voltage bus (6), which is accessed by the at least one first DC voltage converter (4.1, 4.2). Charging station (1) according to one of the preceding claims, wherein the at least one first DC voltage converter (4.1, 4.2) delivers the second DC voltage (U2.1, U2.2) to a second DC voltage bus (7), which is accessed by the second DC voltage converter (5.1-5.4). Charging station (1) according to one of the preceding claims, wherein respective third DC voltages (U3.1 - U3.4) are fed from at least some of the second DC voltage converters (5.1-5.4) to different charging points (2.1-2.4). Charging station (1) according to one of the preceding claims, further comprising: a control device (8) which is configured to communicate with a communication device of a consumer connected to the at least one charging point (2.1 - 2.4), which supplies the control device (8) with a setpoint value for the third direct voltage (U3.1 - U3.4 ), a power required by the consumer and / or a fill level of a battery of the consumer is transmitted, the control device (8) being configured to derive a power required for charging the consumer from the fill level, wherein the control device (8) the second direct voltage (U2.1, U2.2) output by the at least one first direct voltage converter (4.1, 4.2) and / or the third direct voltage (U3.1 - U3.4) regulates in order to provide the setpoint for the third direct voltage (U3.1 - U3.4) and / or the required power. Charging station (1) according to one of the preceding claims, wherein the second DC voltage converters (5.1-5.4) each have an insulation monitor. Method for charging a consumer at a charging point (2.1-2.4) of a charging station (1), the charging station (1) having the following: at least one rectifier (3) which rectifies an alternating voltage to a first direct voltage (U1); at least one first DC voltage converter (4.1, 4.2), which converts the first DC voltage (U1) to a second DC voltage (U2.1, U2.2), with between the first DC voltage (U1) and the second DC voltage (U2.1, U2 .2) there is electrical isolation; and a plurality of second DC voltage converters (5.1-5.4) which are connected in parallel to the at least one first DC voltage converter (4.1, 4.2) and each converts the second DC voltage (U2.1, U2.2) to a third DC voltage (U3.1 - U3.4), with no potential separation between the second DC voltage (U2.1, U2.2) and the third DC voltage (U3.1 - U3.4), and the third DC voltage (U3.1 - U3. 4) at which at least one charging point (2.1-2.4) can be tapped; the method comprising the steps of: Recording a setpoint for the third DC voltage (U3.1 - U3.4), a required power for charging the consumer or a level of a battery of the consumer at the charging point (2.1 - 2.4), with a required power for charging the Consumer is derived; and Regulation of the second direct voltage (U2.1, U2.2) output by the at least one first direct voltage converter (4.1, 4.2) and / or the third direct voltage (U3.1 - U3.4) output by the second direct voltage converters (5.1-5.4) to achieve the setpoint for the third DC voltage (U3.1 - U3.4) and / or the required power.

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