DE102020119492B4 - Charger arrangement and method for controlling a charger arrangement - Google Patents

Abstract

Charger arrangement (23) which has a control unit (28), a charger (30) and a housing (231), which charger (30) has first connections (321), an AC/DC converter (32), a DC intermediate circuit (34), a first DC/DC converter (36) and second connections (363, 364), which housing (231) contains the control unit (28) and the charger (30), which control unit (28) is designed to control the AC/DC converter (32) and the battery contactor arrangement (40), and on which DC intermediate circuit (34) DC consumer connections (51, 52, 53, 54) for connecting DC consumers (55, 56, 57, 58) are provided, characterized in that a battery contactor arrangement (40) is provided in the housing (231), which has third connections (401, 402) and fourth terminals (403, 404) and is controllable by the control unit (28), wherein the first DC/DC converter (36) is designed as a bidirectional DC/DC converter (36) to enable, in a charging mode, a conversion of a first DC voltage at the DC intermediate circuit (34) into a second DC voltage at the second terminals (363, 364), and to enable, in a consumption mode, a conversion of a third DC voltage at the second terminals (363, 364) into a fourth voltage at the DC intermediate circuit (34), and which control unit (28) is designed to enable a corresponding control of the first DC/DC converter (36), wherein the control unit (28) has a voltage regulator (282), which voltage regulator (282) is designed to regulate the voltage at the DC intermediate circuit (34) to a voltage setpoint in the consumption mode in order to thereby enable a determination/setting of the fourth voltage by the voltage regulator (282) to enable.

Description

The invention relates to a charging device arrangement according to the preamble of claim 1. Furthermore, the invention relates to a method for controlling a charging device arrangement.

The EP 3 183 795 B1 , the CN 104 494 535 A , the CN 209 617 055 U , the CN 209 972 203 U , the US 2009 / 0 103 341 A1 and the US 2016 / 0 016 479 A1 show AC chargers for electric vehicles. In addition, the US 2019 / 0 115 848 A1 a generic charger arrangement is known. Furthermore, DE 10 2018 104 914 A1 a power arrangement in which a contactor arrangement is integrated is known. DE 10 2016 007 948 A1 A charger arrangement is also known in which a first DC/DC converter is designed as a bidirectional DC/DC converter.

It is therefore an object of the invention to provide a new charger arrangement.

This problem is solved by the subject matter of claim 1.

A charger arrangement comprises a control unit, a charger, a battery contactor arrangement and a housing, which charger has first connections, an AC/DC converter, a DC intermediate circuit, a first DC/DC converter and second connections, which battery contactor arrangement has third connections and fourth connections, and which housing contains the control unit, the charger and the battery contactor arrangement, which control unit is designed to control the AC/DC converter, the first DC/DC converter and the battery contactor arrangement, and on which DC intermediate circuit DC load connections for connecting DC loads are provided.

The provision of the charger, battery contactor assembly, and control unit in a single housing has resulted in significant synergy effects. The required volume, weight, and technical complexity for cabling, connectors and pin headers, interfaces, and interconnection have been significantly reduced through integration. Furthermore, the control unit can control several of the components, thus saving on hardware. The provision of DC load connections on the DC link enables multiple use of the DC link, thus further simplifying the circuit.

The first DC/DC converter is designed as a bidirectional DC/DC converter to enable conversion of a first DC voltage at the DC intermediate circuit into a second DC voltage at the second terminals in a charging mode, and to enable conversion of a third DC voltage at the second terminals into a fourth voltage at the DC intermediate circuit in a consumption mode. The control unit is designed to enable corresponding control of the first DC/DC converter. This enables the use of the DC intermediate circuit to supply voltage to DC consumers when the vehicle is not being charged. Since it involves power electronics, the multiple use of the first DC/DC converter leads to a significant reduction in the weight of the vehicle. In addition, the voltage range at the DC intermediate circuit can be reduced compared to the voltage range of the battery, and this allows the DC consumers to be designed with less circuitry than DC consumers with a wide input voltage range, as required for direct connection to the battery.

The control unit also includes a voltage regulator, which is designed to regulate the voltage at the DC link to a setpoint voltage in consumption mode, thereby enabling the fourth voltage to be determined/set by the voltage regulator. The use of a voltage controller is also possible, but a voltage regulator has proven very advantageous with regard to the DC loads connected to the DC link, as it reduces the circuit complexity for voltage adjustment at the DC loads.

According to a preferred embodiment, the control unit has an interface, which interface is designed to receive a first piece of information from at least one DC load, which first piece of information characterizes the energy requirement of the DC load, and which control unit is designed to determine the level of the fourth voltage at the DC intermediate circuit in consumption mode as a function of the first piece of information from the at least one DC load and to control the first DC/DC converter accordingly.

According to a preferred embodiment, the control unit is designed to receive a first piece of information from at least two DC consumers via the interface. By receiving such information, the control unit preferably sets the level of the fourth voltage advantageously.

According to a preferred embodiment, the control unit comprises a microcontroller or microprocessor configured to control the AC/DC converter, the first DC/DC converter, and the battery contactor assembly. The multiple use of a microcontroller or microprocessor simplifies communication and enables effective optimization.

According to a preferred embodiment, a DC load is provided in the housing. This DC load is connected to the DC intermediate circuit and is designed as a heater for heating a fluid. Such a heater can be used to heat the high-voltage battery or the passenger compartment. The arrangement of such a DC load in the housing has proven extremely advantageous, since the heat loss from the charging arrangement can also be used to heat the fluid, while simultaneously cooling the charging arrangement. The resulting weight savings and efficiency increase are significant.

• - zweiter DC/DC-Wandler,
• - Heizgerät für ein Fluid,
• - elektrischer Klimakompressor,
• - Wankstabilisierungsanordnung, und
• - Innenraumheizer.

According to a preferred embodiment, at least one first DC consumer is connected to the DC consumer terminals from the DC consumer group consisting of:

• - second DC/DC converter,
• - heater for a fluid,
• - electric air conditioning compressor,
• - Roll stabilization arrangement, and
• - Interior heater.

For these consumers, significant efficiency improvements are possible by connecting them to the DC link and controlling the first DC/DC converter of the charging system accordingly.

According to a preferred embodiment, a second DC/DC converter is connected to the DC load terminals, and the control unit is configured to control the second DC/DC converter. This allows the control unit to directly influence the second DC/DC converter and control it in an optimized manner with regard to the charging arrangement.

According to a preferred embodiment, a fluid heater is connected to the DC load terminals, and the control unit is configured to control the fluid heater. This allows the control unit to directly influence the heater and control it in an optimized manner with respect to the charger arrangement.

According to a preferred embodiment, a second DC/DC converter is connected to the DC load terminals to enable voltage conversion at the DC link. This conversion can involve increasing or decreasing the voltage as needed. For example, a voltage suitable for the low-voltage vehicle electrical system can be generated.

The problem is also solved by a method for controlling a charging arrangement, in which the control unit, when determining the fourth voltage, gives greater weight to the DC load with the highest energy demand than to the other DC loads. The DC load with the highest energy demand often also has the highest power loss, and since the power loss depends on the voltage at the DC intermediate circuit, giving this DC load greater weight allows for a more advantageous determination of the fourth voltage.

According to a preferred embodiment, the control unit calculates the fourth voltage using an optimization method designed to reduce the total power loss of the first DC/DC converter and the DC loads. Especially in battery-powered vehicles, reducing the total power loss enables an increase in the vehicle's range.

According to a preferred embodiment, the control unit is configured to change the fourth voltage in consumption mode and to check whether the electrical power at the DC link or at the second terminals is reduced by this change, thereby enabling a reduction in power loss. Such a configuration enables optimization of power loss by maintaining a positive change and reversing a negative change. By always making only small changes, the DC loads can operate with the new voltage without major adjustment, and this enables a comparatively rapid optimization of the fourth voltage.

• 1 ein Fahrzeug mit einer Ladegerätanordnung an einer Ladestation, und
• 2 eine mögliche Optimierung der Spannung an einem Gleichstromzwischenkreis.

Further details and advantageous developments of the invention will become apparent from the descriptions below and the drawings, which are in no way intended as a limitation. of the invention and from the subclaims. They show:

• 1 a vehicle with a charger arrangement at a charging station, and
• 2 a possible optimization of the voltage on a DC link.

In the following, identical or equivalent parts are provided with the same reference symbols and are usually described only once. The description builds on each figure to avoid unnecessary repetition.

1 shows a schematic representation of an embodiment with a vehicle 10 connected to a charging station 12. The vehicle 10 has a charging device arrangement 23, which can be connected to the charging station 12 via a charging connection 24 and which can be connected to a battery 26, in particular to a high-voltage battery, via a battery connection 25. The charger assembly 23 has a control unit 28, a charger 30, a battery contactor assembly 40, and a housing 231. The charger 30 has first terminals 321 for connection to the charging port 24, an AC/DC converter 32, a DC link 34, a DC/DC converter 36, which is connected to the AC/DC converter via the DC link 34, and second terminals 363, 364 for connecting the DC/DC converter 36 to the battery contactor assembly 40. The battery contactor assembly 40 has third terminals 401, 402 for connection to the DC/DC converter 36 and fourth terminals 403, 404 for connection to the battery port 25. The housing 231 preferably contains at least the control unit 28, the charger 30, and the battery contactor assembly 40. The control unit 28 is for controlling the AC/DC converter 32, the DC/DC converter 36 and the battery contactor arrangement 40, and on the DC intermediate circuit 34, DC consumer connections 51, 52, 53, 54 for connecting DC consumers 55, 56, 57, 58 are provided via lines 49, 50.

The battery contactor assembly 40 enables a separation between the battery 26 and the charger 30. In English it is also referred to as a battery junction box.

The DC load 57 is preferably a heater, in particular a heater for a fluid such as water. Heated water is advantageous, for example, for preconditioning the battery 26. The DC load 58 is, for example, another DC/DC converter, which can convert the DC voltage at the DC intermediate circuit 34 into a higher or lower voltage and provide it at a terminal 64. The DC loads 55, 56 are, for example, an electric air conditioning compressor, a roll stabilization arrangement, an interior heater, or another device operated with a DC voltage.

The charger 30 can be galvanically isolated from the charging station 12 (e.g. via a transformer) or galvanically connected.

The control unit 28 preferably has a microcontroller or microprocessor 281, and it enables control of various devices, in particular the AC/DC converter 32, the DC/DC converter 36 and the battery contactor arrangement 40, via the microcontroller or microprocessor 281.

The control unit 28 preferably has a voltage regulator 282 which is designed to regulate the voltage at the DC link 34 to a voltage setpoint in a consumption mode.

The control unit 28 has an interface 61, which is connected to the DC loads 55, 56, 57, 58 via data lines 60. Wireless transmission is also possible. The interface 61 enables input and/or output.

The DC/DC converter 36 is preferably designed as a bidirectional DC/DC converter 36. In a charging mode, it enables the conversion of a first DC voltage at the DC intermediate circuit 34 into a second DC voltage at the second terminals 363, 364. This enables, for example, a charging process in which an alternating current is supplied to the AC/DC converter 32 via the charging station 12, the alternating current is converted by the AC/DC converter 32 into a direct current at the DC intermediate circuit 34, and the DC/DC converter then converts the voltage at the DC intermediate circuit 34 into a voltage suitable for the battery 26 at the terminals 363, 364.

The DC intermediate circuit 34 has a first line 341 (positive line) and a second line 342 (negative line), which are connected to terminals 323, 324 of the AC/DC converter 32 and to terminals 361, 362 of the DC/DC converter 36. The lines 341, 342 are interconnected by a capacitor arrangement 343. The capacitor arrangement 343 is exemplary. Typically, more complex filter circuits are also provided to smooth the current and voltage and to improve EMC (electromagnetic compatibility) in the DC intermediate circuit.

In a consumption mode in which energy from the battery 26 is used to operate the direct current consumers 55, 56, 57, 58 and the vehicle 10 is not connected to a charging station 12 for charging, a third direct current voltage at the second terminals 363, 364, which can be generated by the battery 26, is converted at least temporarily into a fourth voltage at the direct current intermediate circuit 34. This enables dual use of the DC/DC converter 36 both for the charging process and for providing a fourth voltage suitable for the direct current consumers 55, 56, 57, 58 when the vehicle 10 is not connected to the charging station 12 for charging.

The control unit 28 is preferably configured to receive, via the interface 61, first information from at least one of the DC loads 55, 56, 57, 58, which first information characterizes the energy demand of the DC load 55, 56, 57, 58. This first information can, for example, be a value for the required electrical power of the DC load, or, for example, a value between zero and one, where zero corresponds to a switched-off DC load and one to a DC load operating at full power. The first information can, for example, also include the current power loss of the DC load, which depends, among other things, on the energy demand.

Preferably, the control unit 28 is designed to receive such first information from at least two DC consumers 55, 56, 57, 58 via the interface 61.

In practice, different DC consumers operate with varying degrees of efficiency at different input voltages. For example, an air conditioning compressor can operate most efficiently at a voltage of 700 volts on the DC link 34, while a roll stabilization arrangement, for example, operates most efficiently at a voltage of 400 volts.

Preferably, the control unit 28 contains data on the power loss of the individual DC consumers as a function of the first information.

Preferably, the control unit 28 determines the fourth voltage depending on the DC load 55, 56, 57, 58 that has the highest energy demand. For this purpose, the DC load with the highest energy demand can preferably be given greater weighting, and the remaining DC loads can be given less consideration.

2 shows, as an example, a plot of the power loss P_V in watts against the fourth voltage U at the DC link 34 in volts for a first consumer V1 and a second consumer V2, each with a given energy requirement. The first consumer V1 has a higher overall power loss P_V than the second consumer V2. The first consumer V1 has a low point at a voltage U of approximately 570 volts, and the power loss P_V increases sharply at lower and higher voltages U. This is an approximately parabolic curve.

The second DC load V2, on the other hand, has a comparatively flatly increasing power loss P_V with a slightly positive curvature.

The curve V1 + V2 shows the sum of the power losses P_V of the loads V1 and V2. The low point is at a slightly lower voltage of approximately 550 volts than the low point of the curve of the first DC load V1. An optimization process, via which the fourth voltage is calculated, preferably takes place in the control unit 28. The optimization process is preferably designed to reduce the total power losses of the DC/DC converter and the DC loads 55, 56, 57, 58. In the exemplary embodiment, the voltage at the low point of the curve V1 + V2 can be selected as the optimized fourth voltage. More complicated processes are naturally also possible, e.g. the use of a Lagrange optimization process in which constraints are taken into account as Lagrange multipliers.

It is also possible to measure the current flowing on the battery side of the DC/DC converter or the current flowing at the DC link 34 and to find a minimum or at least an improvement by varying the fourth DC voltage at the DC link 34. Such an optimization process can take place at the beginning of the consumption mode or continuously.

Claims (12)

Charger arrangement (23) which has a control unit (28), a charger (30) and a housing (231), which charger (30) has first connections (321), an AC/DC converter (32), a DC intermediate circuit (34), a first DC/DC converter (36) and second connections (363, 364), which housing (231) contains the control unit (28) and the charger (30), which control unit (28) is designed to control the AC/DC converter (32) and the battery contactor arrangement (40), and to which DC intermediate circuit (34) DC consumer connections (51, 52, 53, 54) for connecting of direct current consumers (55, 56, 57, 58) are provided, characterized in that a battery contactor arrangement (40) is provided in the housing (231), which has third terminals (401, 402) and fourth terminals (403, 404) and can be controlled by the control unit (28), wherein the first DC/DC converter (36) is designed as a bidirectional DC/DC converter (36) to enable, in a charging mode, a conversion of a first direct voltage at the direct current intermediate circuit (34) into a second direct voltage at the second terminals (363, 364), and to enable, in a consumption mode, a conversion of a third direct voltage at the second terminals (363, 364) into a fourth voltage at the direct current intermediate circuit (34), and which control unit (28) is designed to enable a corresponding control of the first DC/DC converter (36), wherein the control unit (28) has a voltage regulator (282), which voltage regulator (282) is designed to regulate the voltage at the DC intermediate circuit (34) to a voltage setpoint in consumption mode in order to enable the fourth voltage to be determined/specified by the voltage regulator (282). Charger arrangement (23) according to Claim 1 , in which the control unit (28) has an interface (61), which interface (61) is designed to receive first information from at least one direct current consumer (55, 56, 57, 58), which first information characterizes the energy requirement of the direct current consumer (55, 56, 57, 58), and which control unit (28) is designed to determine the level of the fourth voltage at the direct current intermediate circuit (34) in consumption mode as a function of the first information from the at least one direct current consumer (55, 56, 57, 58) and to control the first DC/DC converter (36) accordingly. Charger arrangement (23) according to Claim 2 , in which the control unit (28) is designed to receive first information from at least two direct current consumers (55, 56, 57, 58) via the interface (61). Charger arrangement (23) according to one of the preceding claims, in which the control unit (28) has a microcontroller or microprocessor (281) which is designed to control the AC/DC converter (32), the first DC/DC converter (36) and the battery contactor arrangement (40). Charger arrangement (23) according to one of the preceding claims, in which a direct current consumer (57) is provided in the housing (231), which direct current consumer (57) is connected to the direct current intermediate circuit (34) and is designed as a heating device (57) for heating a fluid. Charging arrangement (23) according to one of the preceding claims, in which at least one first DC consumer (55, 56, 57, 58) from the DC consumer group consisting of: - second DC/DC converter (58), - heater (57) for a fluid, - electric air conditioning compressor (55), - roll stabilization arrangement (56), and - interior heater is connected to the DC consumer terminals (51, 52, 53, 54). Charger arrangement (23) according to Claim 6 in which a second DC/DC converter (58) is connected to the DC consumer terminals (51, 52, 53, 54), and in which the control unit (28) is designed to control the second DC/DC converter (58). Charger arrangement (23) according to Claim 6 or 7 in which a heater (57) for a fluid is connected to the DC consumer terminals (51, 52, 53, 54), and in which the control unit (28) is designed to control the heater (57) for the fluid. Charger arrangement (23) according to one of the preceding claims, in which a second DC/DC converter (58) is connected to the DC consumer terminals (51, 52, 53, 54) in order to enable conversion of the voltage from the DC intermediate circuit (34). Method for controlling a charging arrangement (23) according to Claim 3 , in which the control unit (28) weights the DC consumer (55, 56, 57, 58) having the highest energy requirement more heavily than the other DC consumers (55, 56, 57, 58) when determining the fourth voltage. Method for controlling a charging arrangement (23) according to Claim 4 , in which the control unit (28) calculates the fourth voltage by an optimization method, which optimization method is designed to reduce the total power loss of the first DC/DC converter (36) and the DC consumers (55, 56, 57, 58). Method for controlling a charging device (23) according to one of the preceding claims, in which the control unit (28) carries out a change in the fourth voltage in the consumption mode and checks whether the electrical power at the DC intermediate circuit (34) or at the second terminals (363, 364) is reduced by this change or not, in order to thereby enable a reduction in the power loss.

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