Method for operating an electrical power supply device, shutdown control device and power supply device

Abstract

The invention relates to a method for operating an electrical power supply device (1) for unidirectional or bidirectional charging of an energy storage device (2), wherein - during a charging process, a temporal charging parameter gradient of a charging parameter characteristic of the charging process is recorded, wherein, - if a disturbance in the charging process is inferred from the detected charging parameter gradient, an emergency measure is taken to protect the power supply device (1) and / or the energy storage device (2) from damage. Furthermore, the invention relates to a shutdown control device (5) for carrying out such a method and a power supply device (1) with such a shutdown control device (5).

Description

[0001] The invention relates to a method for operating an electrical power supply device for unidirectional or bidirectional charging, in particular an energy storage device, a shutdown control device and a power supply device.

[0002] When charging an energy storage device, particularly an electric vehicle, using a power supply device, it is necessary to ensure that a maximum charging current and / or a maximum charging voltage is not exceeded in order to prevent damage to the energy storage device and / or the power supply device. In particular, it must be ensured that in the event of a malfunction of the power supply device and / or the electrical energy storage device, an electrical connection, especially a power circuit, is interrupted.

[0003] It is known that electric vehicles have a fuse that interrupts the power circuit in the event of a malfunction in the power supply unit. For example, if a short circuit occurs in the power supply unit during a bidirectional charging process—when the electric vehicle is transferring electrical energy to the power supply unit—the electric vehicle transfers energy to the power supply unit at such a high power level that the electric vehicle's fuse trips. A disadvantage of these fuses is that, due to the high current load, they often need to be replaced after only a few switching cycles. Such fuses can also be integrated into the electric vehicle's battery.The electric vehicle is no longer functional after the fuse has blown. To restore the electric vehicle's functionality, it must be towed and the fuse replaced and / or manually reset. Alternatively, the entire battery must be replaced after the fuse has blown.

[0004] It is also known that the power supply devices may have fuses. These fuses are designed to interrupt the power circuit in the event of a malfunction in the power supply device. A disadvantage of this design is that the reaction time of these fuses is so long that both the power supply device fuse and the electric vehicle fuse are blown. Furthermore, it is not possible to interrupt the power circuit in the event of a power supply device malfunction before the electric vehicle fuse blows, thus preserving the functionality of the electric vehicle.Another problem is that a wide variety of electric vehicles can be charged at such a power supply device, meaning that the power supply device does not know the tripping characteristics of the electric vehicle's fuse and therefore cannot protect it.

[0005] DE 10 2023 119 421 A1 discloses a battery charging device for unidirectional charging of a battery, wherein the battery charging device is configured to perform a method in which a time-dependent charging parameter is detected during a charging process, and if a disturbance of the charging process is inferred based on the detected charging parameter, an emergency measure is implemented to protect the power supply device and / or the energy storage device from damage. A further method is disclosed in DE 10 2022 123 557 A1.

[0006] The invention is therefore based on the objective of creating a method for operating an electrical power supply device, a shutdown control device and a power supply device, wherein the aforementioned disadvantages are at least reduced, preferably avoided.

[0007] The problem is solved by providing a method according to claim 1 for operating an electrical power supply device, in particular a charging station, for unidirectional or bidirectional charging of an energy storage device, in particular an electric vehicle, and in particular a battery storage unit of an electric vehicle. Further embodiments are described in the dependent claims.

[0008] The procedure involves recording a time-dependent charging parameter gradient of a characteristic charging parameter during a charging process. If a fault in the charging process is inferred from the recorded charging parameter gradient, an emergency measure is implemented to protect the power supply device and / or the energy storage device from damage.

[0009] Advantageously, the charging parameter gradient allows for earlier detection of a charging process disturbance than the associated charging parameter itself. In particular, the method's reaction time is in the microsecond range. Specifically, it is not necessary for a charging parameter itself to reach a charging parameter threshold before a charging process disturbance can be detected. It is sufficient if the rate of change of the charging parameter—the charging parameter gradient—is outside a predetermined range or above a threshold to detect a charging process disturbance. Therefore, it is advantageously unnecessary to know the tripping characteristics and / or the rated current of an electric vehicle fuse. In particular, fixed disconnection thresholds for the power supply device are not required.This method thus allows energy storage devices with fuses exhibiting different tripping characteristics and / or rated currents to be protected from damage, even if these tripping characteristics and / or rated currents are unknown to the power supply device. Advantageously, this makes it possible to interrupt the power circuit of the electrical power supply device in the event of a malfunction before the energy storage device registers the malfunction and, in particular, before a fuse in the energy storage device trips.

[0010] In the context of this technical teaching, the term "charging" refers to both charging and discharging. During a charging process, the energy storage device is charged by the power supply device. During a discharging process, the energy storage device is discharged, and the energy is transferred to the power supply device. The transferred energy can be fed into a power grid to which the power supply device is connected in order to stabilize or temporarily support it. The power supply device thus serves as an access point to the power grid. Alternatively or additionally, an energy storage device of the power supply device can be charged with the transferred energy. Unidirectional charging typically includes only charging processes, while bidirectional charging includes both charging and discharging processes.In the context of this technical teaching, a charging parameter is therefore understood to be, in particular, a charging parameter and a discharging parameter.

[0011] In the context of this technical teaching, a positive charging current is an energy transfer from the power supply device to the energy storage device – i.e., charging. Furthermore, in the context of this technical teaching, a negative charging current is an energy transfer from the energy storage device to the power supply device – i.e., discharging.

[0012] In one embodiment of the method, a bidirectional charging current is monitored. This advantageously also allows monitoring of the charging current from the energy storage device to the electrical power supply device. Furthermore, in the event of a malfunction of the power supply device during bidirectional charging, it is advantageous to prevent the energy storage device's fuse from tripping and, for example, rendering an electric vehicle inoperable. Instead, it prevents the electric vehicle's fuse from being exposed to operation with charging parameters that deviate from normal operation. This proves particularly advantageous for batteries with an integrated fuse. Because the fuse does not trip, these batteries no longer need to be replaced at considerable expense. Ultimately, towing and repairing the electric vehicle is advantageously avoided.

[0013] In electrical engineering, a power supply device, especially a charging station, refers to any device or electrical system, particularly stationary or mobile, that serves to supply energy to mobile battery-powered devices, machines, or motor vehicles simply by placing them on the charging station or plugging them in, without necessarily having to remove the energy storage device—for example, the traction battery of an electric car. Charging stations for electric cars are sometimes also called "electric vehicle charging stations" and can include multiple charging points. Particularly well-known are direct current fast charging systems (high-performance charging systems or high-power charging systems, HPC systems), such as the combined charging system (CCS), which is widespread in Europe.In conventional DC charging, direct current from the charging station is fed directly into the vehicle's battery. This is achieved by a high-performance rectifier, preferably located in the charging station, supplied by the grid or by large buffer batteries at, for example, solar charging stations. The vehicle contains a battery management system that communicates directly or indirectly with the charging station to adjust the current and voltage or to terminate the charging process when a predetermined capacity limit is reached. The power electronics for the charging circuit are typically located in the charging station. Because the DC connections of the charging station are directly connected to the corresponding terminals of the traction battery—without the need for an AC / DC converter in the vehicle—high charging currents can be transmitted with minimal loss, resulting in short charging times.

[0014] In one embodiment, the power supply device, in particular the charging station, is designed as a charging column. In particular, the charging station has at least one charging point, in particular exactly one charging point or exactly two charging points.

[0015] In particular, the charging station is designed as a fast charging station. In one embodiment, the charging station is designed as a battery-supported charging station, especially as a battery-supported fast charging station, and thus has a device-integrated energy storage system.

[0016] According to a further development of the invention, the charging parameter gradient is directly detected and compared to a predetermined gradient threshold. A disturbance in the charging process is inferred if the detected charging parameter gradient exceeds the predetermined gradient threshold. Alternatively, the charging parameter gradient is indirectly detected by measuring a characteristic parameter and comparing it to a predetermined threshold. A disturbance in the charging process is inferred if the measured parameter exceeds the predetermined threshold.

[0017] In one embodiment, the charging parameter gradient and / or the measurement parameter is recorded without a sign, in particular as a magnitude, squared magnitude, or squared magnitude. Accordingly, the gradient threshold and / or the measurement parameter threshold is preferably a sign-free quantity, in particular a magnitude. The fact that the charging parameter gradient or the characteristic measurement parameter exceeds the assigned threshold thus means, in particular, that its magnitude is greater—and therefore, in particular, "steeper"—than the threshold, regardless of the sign of the charging parameter gradient or the characteristic measurement parameter.

[0018] In the context of this technical teaching, the direct measurement of the charging parameter gradient means, in particular, that a physical quantity of the charging parameter gradient is directly measured and derived over time. Specifically, charging power, charging current, or charging voltage is directly measured.

[0019] In the context of this technical teaching, the fact that the charging parameter gradient is indirectly measured means, in particular, that a physical quantity dependent on the charging parameter gradient is directly measured, namely the measurement parameter characteristic of the charging parameter gradient. Specifically, a temporal gradient of the charging power, a charging current, or a charging voltage is indirectly measured by measuring the measurement parameter characteristic of the charging parameter gradient.

[0020] According to a further development of the invention, it is provided that, as an emergency measure, a power circuit of a power electronics, in particular the power supply device or the energy storage device, is interrupted, in particular in such a way that the charging process is interrupted.

[0021] In one embodiment, the power circuit is interrupted by means of a disconnection device. The disconnection device is specifically designed to interrupt the power circuit.

[0022] According to a further development of the invention, it is provided that at least one charging current parameter is used as the charging parameter, which is selected from a group consisting of: a charging power, a charging current, a charging voltage and a combination of at least two of the aforementioned charging current parameters.

[0023] In one embodiment – ​​where the charging parameter gradient is detected indirectly – the measured parameter is a voltage drop across a measuring section – through which the charging current or a partial current dependent on the charging current flows – due to an inductance, particularly of electronic components of the power supply device, especially a shutdown control device of the power supply device. The voltage drop u(t) across the measuring section, which has the inductance L, is directly dependent on – in particular according to the equation u(t) = L-dI(t) / dt – the time gradient of the charging current or partial current I(t) and thus on the charging parameter gradient. In one embodiment, the measured parameter is a voltage drop across a coil through which the charging current or partial current flows. Alternatively, the measuring section has the inductance as a parasitic inductance.In this context, "parasitic" means in particular that a section of the conductor or several indeterminate, not clearly defined components and / or conductor sections of the power supply device and / or the energy storage device are the cause of the inductance.

[0024] According to a further development of the invention, it is provided that at least one threshold value, selected from the gradient threshold value and the measurement parameter threshold value, is set depending on a limit charging parameter, which is selected from a group consisting of: a permissible power gradient limit, a permissible power limit, a permissible current gradient limit, a permissible current limit, a permissible voltage gradient limit, a permissible voltage limit and a combination of at least two of the aforementioned limits.

[0025] In one embodiment, the limiting charging parameter is detected by receiving data transmitted between the power supply device and the energy storage device during a charging process. This data includes at least one limiting charging parameter characteristic of the charging process. Depending on this at least one limiting charging parameter, the gradient threshold of the power supply device for the charging parameter gradient is set. If the charging parameter gradient exceeds the gradient threshold, an emergency measure is implemented, particularly to protect the power supply device and / or the energy storage device from damage.

[0026] In one embodiment, the gradient threshold is set by determining a target gradient threshold for the power supply device for the charging parameter, depending on the at least one limit charging parameter. It is checked whether the current actual value of the gradient threshold of the power supply device is equal to, and in particular, has the same value as, the target gradient threshold. If the current actual value is not equal to, and in particular does not have the same value as, the gradient threshold is adjusted so that a new actual value of the gradient threshold is equal to, and in particular has the same value as, the target value.

[0027] In one embodiment, data from a data transmission using an electrical line in a low-voltage network (Powerline Communication (PLC)) and / or a serial bus system (Controller Area Network (CAN)) is acquired and / or received. Specifically, the acquiring device is configured to receive data from a data transmission using an electrical line in a low-voltage network (Powerline Communication (PLC)) and / or a serial bus system (Controller Area Network (CAN)). In particular, the electrical line runs from the power supply device to the energy storage device, especially within a charging cable. The electrical line is, in particular, a line within the charging cable that is distinct from the power circuit.

[0028] The data can be acquired directly or indirectly: Data can be acquired directly by setting up a data acquisition device to communicate with the power supply device via a communication interface, preferably a serial bus system or a network interface. Preferably, the data acquisition device communicates directly with the control device and / or the power electronics. Data can be acquired indirectly by setting up the data acquisition device to capture the data transmission along a data transmission path, particularly without communicating directly with the control device. In this case, the data transmission path can be opened, particularly by interrupting it, with the data acquisition device being placed between the two paths, and the data transmission path then being closed again.Alternatively, the detection device can capture the data transmission without an electrical connection to the data transmission path itself – essentially eavesdropping on the data transmission, particularly without electrical contact, especially galvanically decoupled, especially inductively. This is preferably done at the line or charging cable.

[0029] Advantageously, at least one gradient threshold can be flexibly adapted to different energy storage devices. For example, the gradient threshold can be set lower – i.e., less steep – for a small electric vehicle with a maximum charging current of 125 A (at a charging voltage of 400 V, this results in a charging power of 50 kW) than for an electric commercial vehicle with a maximum charging current of 625 A (at a charging voltage of 400 V, this results in a charging power of 250 kW), where the gradient threshold is set higher – i.e., steeper. This allows different electric vehicles to be protected from damage.

[0030] In a preferred embodiment, the gradient threshold is set depending on a permissible current gradient limit. In a preferred embodiment, the measurement parameter threshold is set depending on a permissible voltage limit.

[0031] In one embodiment, at least one threshold value, selected from the gradient threshold value and the measurement parameter threshold value, is set depending on a temporal fluctuation of the charging parameter and / or the charging parameter gradient and / or the measurement parameter.

[0032] In one embodiment, the current gradient of a power supply device operating with a fault-free charging process ranges from 20 A / s to 100 A / s. However, in a power supply device operated with a short-circuited energy storage device, the current gradient can be greater than 1.5 A / µs. Previous measurements have shown a current gradient of up to 340 A / µs in the case of a short circuit. The charging current ripple can exhibit a gradient of up to 20 A / µs. After smoothing by means of a capacitor, the ripple current gradient can be as low as 1 A / µs.The maximum permissible ripple current gradient according to standard IEC 61851-23 in its version valid on the date relevant for the priority date of the present application can be 2.7 A / µs, in particular standardized to a charging current of 9 A with a ripple current frequency of up to 150 kHz. The ripple current is, in particular, an alternating current of any frequency and waveform superimposed on a direct current, in particular the charging current. In particular, the charging current is superimposed with a ripple current having a frequency of 80 kHz to 120 kHz, in particular 100 kHz.

[0033] In a preferred embodiment, the gradient threshold is set depending on a permissible current gradient limit of a charging current during the charging process, wherein the current gradient limit is up to 100 A / s, particularly 100 A / s. In particular, in this embodiment, the ripple current is smoothed so that the ripple current gradient is up to 1 A / µs. Advantageously, this allows for a particularly rapid detection of a charging process disturbance and the implementation of emergency measures, in particular the interruption of the power circuit.

[0034] In yet another preferred embodiment, the gradient threshold is set depending on a permissible current gradient limit of the ripple current and a permissible current gradient limit of the charging current. In particular, the gradient threshold is set such that it lies within an interval between the permissible current gradient limit of the ripple current and the current gradient limit of the charging current. In one embodiment, the gradient threshold is set to a value between 1 A / µs and 1.5 A / µs, particularly 1.3 A / µs.

[0035] According to a further development of the invention, it is provided that the charging parameter gradient and / or the measurement parameter is detected at a line, a charging cable that connects the power supply device to the energy storage device, a power electronics, an electrical interface and / or at a control device of the power supply device.

[0036] Advantageously, the charging parameter gradient and / or the measurement parameter can be easily acquired. It is possible for the charging parameter gradient and / or the measurement parameter to be redundantly acquired at different locations, in particular at least two locations, of the power supply device. Specifically, each location has at least two measurement points. These measurement points can, in particular, define the measurement path, with the voltage between the measurement points being measured as the measurement parameter.

[0037] In one embodiment, the method is carried out repeatedly, particularly after a predetermined time interval, and especially cyclically. In particular, the method is carried out at a frequency of 10 kHz to 50 kHz.

[0038] The problem is also solved by providing a shutdown control device according to claim 7 for a power supply device for unidirectional or bidirectional charging of an energy storage device, in particular an electric vehicle, especially a battery storage unit of an electric vehicle. Further embodiments are described in the dependent claims.

[0039] The shutdown control device is configured to carry out a method according to the invention or a method according to one or more of the embodiments described above. The advantages of the shutdown control device are particularly evident in connection with the method itself.

[0040] According to a further development of the invention, the shutdown control device is designed to be operatively connected to a power circuit of the power supply device and to interrupt the power circuit.

[0041] In one embodiment, the shutdown control device is configured to be interconnected with a shutdown arrangement of the power supply device for control purposes.

[0042] According to a further development of the invention, it is provided that the shutdown control device is formed by a control device of the power supply device.

[0043] In particular, the control device is designed to be interconnected with the shutdown arrangement for control purposes.

[0044] In one embodiment, the shutdown control device is integrated into a control device of the power supply device. In another embodiment, the shutdown control device is designed as a control device of the power supply device.

[0045] The problem is also solved by providing a power supply device according to claim 10 for unidirectional or bidirectional charging of an energy storage device, in particular an electric vehicle, and especially a battery storage unit of an electric vehicle. Further embodiments are described in the dependent claims.

[0046] The power supply device comprises power electronics, a shutdown control device according to the invention or a shutdown control device according to one or more of the embodiments described above, and an electrical interface. The power electronics are configured to selectively close or open a power circuit for charging the energy storage device. The electrical interface is configured to connect to the energy storage device for charging.

[0047] In one embodiment, the power supply device includes a shutdown arrangement. In particular, the shutdown control device is functionally connected to the shutdown arrangement. Specifically, the shutdown arrangement is configured to receive an interruption signal from the shutdown control device and subsequently interrupt the power circuit.

[0048] In the context of this technical teaching, an interrupt signal is understood to be, in particular, an electrical signal. This electrical signal can be a control voltage at a gate terminal of a power semiconductor device.

[0049] According to a further development of the invention, it is provided that the shutdown control device is integrated into a control device of the power supply device or is designed as a control device of the power supply device.

[0050] In particular, the control device is interconnected with the shutdown arrangement. Specifically, the shutdown arrangement is configured to receive the interruption signal from the control device and subsequently interrupt the power circuit.

[0051] In one embodiment, the shutdown arrangement comprises a first controllable power semiconductor component and a second controllable power semiconductor component. The first power semiconductor component and the second power semiconductor component are arranged in anti-series. The first power semiconductor component and the second power semiconductor component are configured to conduct the charging current of the power supply device when switched on. The shutdown control device is operatively connected to the first power semiconductor component and the second power semiconductor component and configured to control them respectively.Furthermore, the shutdown control device is designed to detect the value of at least one charging parameter characteristic of the charging current, and, depending on the detected value, to switch off the first power semiconductor component and / or the second power semiconductor component, thereby interrupting the charging current, in particular the power circuit.

[0052] Optionally, the shutdown arrangement includes a diode, wherein the diode, the first power semiconductor component and the second power semiconductor component are arranged as a T-circuit.

[0053] In the context of this technical teaching, a T-circuit, in particular, connects three electrical components at a single connection point. Specifically, the first terminal of the first component, in particular the first power semiconductor component, and the first terminal of the second component, in particular the second power semiconductor component, are electrically connected via this connection point. Additionally, the first terminal of the first component and the first terminal of the third component, in particular the diode, are electrically connected via this connection point. Furthermore, the first terminal of the second component and the first terminal of the third component are electrically connected via this connection point.Furthermore, a second terminal of the first component and a second terminal of the third component are connected or connectable to a voltage or current source, in particular the power supply device or the energy storage device. In addition, a second terminal of the second component and the second terminal of the third component are connected or connectable to a load, in particular the energy storage device, wherein the voltage or current source and the load are configured differently.

[0054] In particular, after the interruption, the diode takes over the charging current, which is then slowly dissipated across the diode. Advantageously, the diode allows energy from the inductance of the charging current to be dissipated. When the charging current flows through the diode, it exhibits a high current and a low voltage of less than 2 V. Furthermore, the disconnection time is also reduced.

[0055] In one embodiment, the disconnection arrangement is configured such that a positive charging current is always conducted from the second power semiconductor component. Additionally, the disconnection arrangement is configured such that a positive charging current from the first power semiconductor component is interrupted depending on the detected value of at least one characteristic charging parameter. Furthermore, the disconnection arrangement is configured such that a negative charging current is always conducted from the first power semiconductor component. Additionally, the disconnection arrangement is configured such that a negative charging current from the second power semiconductor component is interrupted depending on the detected value of at least one characteristic charging parameter. This is also referred to here as an antiparallel arrangement, in particular as "antiparallel".

[0056] In the context of the present technical teaching, a power semiconductor component has at least one positive terminal and at least one negative terminal. Preferably, a power semiconductor component additionally has a control terminal, wherein the shutdown control device is electrically connected to the control terminal.

[0057] It is particularly preferred that the first power semiconductor component and / or the second power semiconductor component be designed to be unidirectionally blocking.

[0058] In one embodiment, the shutdown control device is configured to compare the detected value with a threshold value selected from the gradient threshold and the measurement parameter threshold, and, depending on the comparison, to switch off the first power semiconductor component and / or the second power semiconductor component, thereby interrupting the charging current. Advantageously, this makes it possible to decide on switching off the first power semiconductor component and / or the second power semiconductor component in a simple and quick manner.

[0059] In one embodiment, the shutdown control device is set up to determine a difference between the detected value and the threshold value, and depending on the difference, to switch off the first power semiconductor component and / or the second power semiconductor component and thereby interrupt the charging current.

[0060] In one embodiment, the first power semiconductor component comprises a first semiconductor switch and a first component diode, wherein the first semiconductor switch and the first component diode are arranged antiparallel. Additionally, the second power semiconductor component comprises a second semiconductor switch and a second component diode, wherein the second semiconductor switch and the second component diode are arranged antiparallel.

[0061] This ensures that an electric current flowing from the positive terminal of the power semiconductor component to the negative terminal is conducted through the semiconductor switch, since the component's diode is reverse-biased. Furthermore, an electric current flowing from the negative terminal of the power semiconductor component to the positive terminal is also conducted through the component's diode, since the component's diode is forward-biased. In addition, due to the anti-series arrangement of the first and second power semiconductor components, the first and second semiconductor switches are also arranged anti-series within the switching device. Advantageously, the first and second semiconductor switches thus form a bidirectional semiconductor switch.Furthermore, the semiconductor switches allow the charging current to be quickly interrupted by means of a corresponding gate signal. Additionally, due to the anti-series arrangement of the first and second power semiconductor components, the first and second component diodes are also arranged anti-series in the shutdown configuration.

[0062] In one embodiment, the first semiconductor switch and / or the second semiconductor switch is configured as a field-effect transistor, in particular as a metal-oxide-semiconductor field-effect transistor (MOSFET). Specifically, the metal-oxide-semiconductor field-effect transistor has a silicon carbide material. If an n-channel field-effect transistor is used, a drain terminal of the field-effect transistor is connected to the positive terminal of the power semiconductor component, and a source terminal of the field-effect transistor is connected to the negative terminal of the power semiconductor component. Alternatively, if a p-channel field-effect transistor is used, the source terminal of the field-effect transistor is connected to the positive terminal of the power semiconductor component, and the drain terminal of the field-effect transistor is connected to the negative terminal of the power semiconductor component.The shutdown control device is particularly preferably configured to detect the semiconductor forward voltage, in particular a gate-source voltage of the field-effect transistor, and to determine a current and / or a voltage as the at least one charging parameter.

[0063] In a further embodiment, the first semiconductor switch and / or the second semiconductor switch is configured as a bipolar transistor with an insulated gate electrode. If an n-channel bipolar transistor is used, one collector terminal of the bipolar transistor is connected to the positive terminal of the power semiconductor component, and one emitter terminal of the bipolar transistor is connected to the negative terminal of the power semiconductor component. Alternatively, if a p-channel bipolar transistor is used, the emitter terminal of the bipolar transistor is connected to the positive terminal of the power semiconductor component, and the collector terminal of the bipolar transistor is connected to the negative terminal of the power semiconductor component. The switch-off control device is particularly preferably configured to detect the semiconductor forward voltage, especially a base-emitter voltage of the bipolar transistor, and to determine a current and / or a voltage from this as the at least one charging parameter.

[0064] In one embodiment, the first semiconductor switch and / or the second semiconductor switch is an insulated-gate bipolar transistor (IGBT). In particular, this transistor is made of silicon. This makes it possible to interrupt the charging current so quickly that any short-circuit current occurring during a malfunction does not exceed I = 1 kA.

[0065] In one embodiment, a cathode of the component diode of the power semiconductor component is assigned to the positive terminal of the power semiconductor component, and an anode of the component diode of the power semiconductor component is assigned to the negative terminal of the power semiconductor component.

[0066] In a particularly preferred embodiment, the first and second components of the power semiconductor are identical.

[0067] In one embodiment, the shutdown control device is designed to switch off the first power semiconductor component and / or the second power semiconductor component by means of the control voltage.

[0068] In particular, the control voltage for switching off the first power semiconductor component and / or the second power semiconductor component is preferably at most 0 V. Specifically, the first power semiconductor component is switched off and thus the charging current is interrupted when a control voltage of at most 0 V is applied to the first power semiconductor component, especially to a gate terminal of the first power semiconductor component. Furthermore, the second power semiconductor component is switched off and thus the charging current is interrupted when a control voltage of at most 0 V is applied to the second power semiconductor component, especially to a gate terminal of the second power semiconductor component.In particular, the first power semiconductor component and the second power semiconductor component are switched on and thus the charging current is not interrupted when a control voltage of 15 V to 20 V is applied to the first power semiconductor component and the second power semiconductor component, especially to the respective gate terminals.

[0069] In one embodiment, the shutdown arrangement, in particular the first power semiconductor component and the second power semiconductor component, is electrically connected in series with an energy storage device that can be connected to the power supply device in a power circuit of the power supply device.

[0070] The invention will be explained in more detail below with reference to the drawing. The drawing shows: Fig. 1 a schematic representation of an exemplary embodiment of a power supply device, Fig. 2 a schematic representation of a process flow diagram of a method for operating the electrical power supply device 1 according to Fig. 1, Fig. 3 a schematic representation of a charging current curve of a trouble-free charging process, Fig. 4 a schematic representation of a charging current curve of a disturbed charging process, whereby the disturbance is inferred by directly detecting the charging parameter gradient and Fig. 5 a schematic representation of the charging current curve according to Fig. 4, whereby the disturbance is inferred by indirectly detecting the charging parameter gradient.

[0071] Fig. Figure 1 shows a schematic representation of an embodiment of a power supply device 1 for unidirectional or bidirectional charging of an energy storage device 2, in particular a battery storage unit of an electric vehicle.

[0072] The power supply device 1 comprises power electronics 3, a shutdown control device 5, and an electrical interface 7. The power electronics 3 are configured to selectively close or open a power circuit 9 for charging the energy storage device 2. The electrical interface 7 is configured to be connected to the energy storage device 2 for charging. In this case, the electrical interface 7 is connected to the energy storage device 2 by means of a charging cable 14.

[0073] The power supply device 1 further comprises a shutdown arrangement 11. The shutdown control device 5 is configured to be operatively connected to the power circuit 9 of the power supply device 1 – via the shutdown arrangement 11 – and to interrupt the power circuit 9. For this purpose, the shutdown control device 5 is operatively connected to the shutdown arrangement 11. The shutdown arrangement 11 is in turn configured to receive an interruption signal from the shutdown control device 5 and subsequently interrupt the power circuit 9.

[0074] The shutdown control device 5 is integrated into a control device 13 of the power supply device 1. In one embodiment (not shown), the shutdown control device 5 is configured as the control device 13 of the power supply device 1. In yet another embodiment (not shown), the shutdown control device 5 is provided separately and additionally to the control device 13 of the power supply device 1 and is preferably operatively connected to it.

[0075] The power supply device 1 and the shutdown control device 5 are specifically designed to carry out a procedure for operating the electrical power supply device 1, which is described in more detail below.

[0076] Fig. Figure 2 shows a schematic representation of a process flow diagram of a first embodiment of a method for operating the electrical power supply device 1 according to Fig. 1 for uni- or bi-directional charging of the energy storage device 2.

[0077] Identical and functionally equivalent elements are provided with the same reference symbols in all figures, so that reference is made to the preceding description in each case.

[0078] In the procedure, in a first step S1, a temporal charging parameter gradient of a charging parameter characteristic of the charging process is recorded during a charging process.

[0079] The charging parameter used is at least one charging current parameter selected from a group consisting of: a charging power, a charging current, a charging voltage, and a combination of at least two of the aforementioned charging current parameters. A charging current can be monitored from the power supply device 1 to the energy storage device 2, as well as vice versa, a process known as bidirectional charging.

[0080] The charging parameter gradient can be detected directly or indirectly: In a second embodiment, not shown in this figure, the charging parameter gradient is detected directly. When the charging parameter gradient is detected directly, it is compared with a predetermined gradient threshold. A fault in the charging process is inferred if the detected charging parameter gradient exceeds the gradient threshold.

[0081] As an alternative to direct measurement, the charging parameter gradient is indirectly measured by measuring a characteristic parameter. In a first step (S2.1) of a second step (S2), this parameter is compared to a predetermined threshold value. In a second step (S2.2) of the second step (S2), if the measured parameter exceeds the threshold value, a disturbance in the charging process is inferred.

[0082] In this embodiment, the measurement parameter is a voltage drop across a measuring section—through which the charging current or a partial current dependent on the charging current flows—due to an inductance, particularly of electronic components of the power supply device 1, especially a shutdown control device 5 of the power supply device 1. The voltage drop u(t) across the measuring section, which has the inductance L, is directly dependent on—in particular, according to the equation u(t) = L-dI(t) / dt, proportional to—the time gradient of the charging current or partial current I(t) and thus on the charging parameter gradient. In one embodiment, the measurement parameter is a voltage drop across a coil through which the charging current or partial current flows. Alternatively, the measuring section has the inductance as a parasitic inductance.In this context, "parasitic" means in particular that a line section or several indeterminate, not clearly defined components and / or line sections of the power supply device 1 and / or the energy storage device 2 are the cause of the inductance.

[0083] The charging parameter gradient and / or the measurement parameter is detected at a line, the charging cable 14, which connects the power supply device 1 to the energy storage device 2, the power electronics 3, the electrical interface 7 and / or at the control device 13 of the power supply device 1.

[0084] At least one threshold value, selected from the gradient threshold and the measurement parameter threshold, is set depending on a limit charge parameter selected from a group consisting of: a permissible power gradient limit, a permissible power limit, a permissible current gradient limit, a permissible current limit, a permissible voltage gradient limit, a permissible voltage limit, and a combination of at least two of the aforementioned limits.

[0085] If, based on the charging parameter gradient indirectly detected via the measurement parameter in the second step S2, a fault in the charging process is inferred, an emergency measure is carried out in a third step S3 to protect the power supply device 1 and / or the energy storage device 2 from damage. As an emergency measure, the power circuit 9 of the power electronics 3 is interrupted, in particular in such a way that the charging process is interrupted.

[0086] Fig. Figure 3 shows a schematic representation of the charging current curve of a trouble-free charging process.

[0087] During the charging process described here, a second embodiment of a method for operating the electrical power supply device 1 is used in accordance with Fig. 1 carried out.

[0088] In this second embodiment of the method, in contrast to the first embodiment of the method, Fig. 2 - The charging parameter gradient – ​​here the charging current gradient – ​​is directly measured. If the charging parameter gradient is measured directly, a fault in the charging process is inferred if the measured charging parameter gradient exceeds a predetermined gradient threshold.

[0089] Diagram a) shows a charging current profile of a fault-free charging process in which the power supply device 1 is charged by the energy storage device 2. Alternatively, the energy storage device 2 can also support or stabilize a power grid, for example, via the power supply device 1.

[0090] Diagram a) shows a charging current I in amperes (A) plotted against time t in seconds (s). The charging process begins at a starting time t0, and the charging current – ​​as a charging parameter – is increased linearly from 0 A (example shown here) until a predetermined charging current I is reached at a first time t1. L This is achieved. Between times t0 and t1, the charging current gradient dI / dt is correspondingly constant and has a positive value (see diagram b)). It is also conceivable that the charging current I is increased non-linearly, for example progressively.

[0091] Diagram b) shows a first derivative of the charging current from diagram a), namely the charging current gradient dI / dt in A / s plotted against time t in s. The charging current gradient represents the time course of the rate of change of the charging current. The gradient threshold value (dI / dt) is also shown. maxThe charging current gradient dI / dt is smaller than the gradient threshold value (dI / dt) during a fault-free charging process. max .

[0092] Diagram a) shows that between the first time t1 and a second time t2, the power supply device 1 with the constant charging current I LThe charging process begins; therefore, the current gradient is zero (see diagram b)). From the second time point t2, the charging current I is again reduced linearly, as an example, until the charging process is complete at a third time point t3. Between times t2 and t3, the charging current gradient dI / dt is therefore constant again, but has a negative value (see diagram b)). It is also conceivable that the charging current I is reduced non-linearly, for example, regressively. The charging process between times t1 and t2 usually takes significantly longer – several minutes to hours – than the increase and decrease of the charging current, which usually takes a few seconds to a minute.

[0093] The upper current limit I is also shown. max , which are above the constant charging current I L lies. The upper current limit I maxThe current limit of the energy storage device 2 is present. If this limit is exceeded, the fuse of the energy storage device 2 is triggered. For example, an electric vehicle would then no longer be drivable.

[0094] At the measurement time tM considered here - as well as at all other times of this charging process - the charging current gradient dI / dt is smaller than the gradient threshold value (dI / dt) max As long as the charging current gradient dI / dt is smaller than the gradient threshold (dI / dt) max This does not indicate a disturbance in the charging process; in particular, the charging process proceeds without disturbance – provided no other disturbances are present. The charging current gradient dI / dt during a disturbance-free charging process preferably ranges from 20 A / s to 100 A / s. The gradient threshold (dI / dt) maxpreferably lies just above 1.0 A / µs, preferably the gradient threshold (dI / dt) max 1.3 A / µs.

[0095] Fig. Figure 4 shows a schematic representation of the charging current profile of a disturbed charging process, where the disturbance is inferred by directly measuring the charging parameter gradient. The charging parameter gradient is measured as the charging current gradient dI / dt.

[0096] The in Fig. Diagrams a) and b) shown in Figure 4 illustrate the charging process of Fig. 3, wherein also the second embodiment of the method for operating the electrical power supply device 1 according to Fig. 1 is carried out.

[0097] The two diagrams of Fig. 4 correspond to the two diagrams of Fig. 3, with the difference that the charging process here is not trouble-free. At a fault time tS, the power supply device 1 is short-circuited due to a fault. The charging current I then rises sharply. Measurements have shown that the charging current gradient dI / dt during a short circuit is greater than 1.5 A / µs and is therefore significantly higher than the charging current gradient dI / dt during a trouble-free charging process, which is preferably from 20 A / s to 100 A / s.

[0098] When using a prior art power supply device 1, the disturbance would cause the charging current I to rise for so long and to such an extent that at a fault time tF the current limit I maxThe safety limit of the energy storage device 2 is exceeded. If the energy storage device 2 is a battery of an electric vehicle, the electric vehicle would no longer be functional from the time of the fault tF.

[0099] This can be prevented by carrying out the present procedure. Diagram b) shows that the charging current gradient dI / dt between times t0 and t1 – as in Fig. 3 - initially smaller than the gradient threshold (dI / dt) max From the first time t1, the charging current gradient dI / dt is initially zero because the power supply device 1 operates with a constant charging current I. L is loading.

[0100] At the time of the disturbance tS, the charging current gradient dI / dt increases abruptly and almost vertically, and usually exceeds the gradient threshold (dI / dt) within a few microseconds. maxThis clearly indicates a charging process malfunction. The emergency measure is implemented by interrupting the power circuit 9 of the power electronics 3 of the power supply device 1. The interruption of power circuit 9 of the power electronics 3 is so rapid that the fuse of the energy storage device 2 is not exposed to the charging process malfunction; in particular, the fuse is not tripped. If the energy storage device 2 is an electric vehicle battery, the electric vehicle would remain functional.

[0101] Fig. Figure 5 shows a schematic representation of the charging current curve according to Fig. 4, whereby the disturbance is inferred by indirectly detecting the charging parameter gradient.

[0102] In contrast to the one in the Fig. 3 and Fig. 4. The second embodiment of the method – in which the charging parameter gradient is directly recorded – is described in Fig. 5 that in Fig. The first embodiment of the method mentioned in section 2 is carried out, in which the charging parameter gradient is detected indirectly. The charging parameter gradient – ​​i.e., the charging current gradient dI / dt – is detected indirectly by measuring a measurement parameter characteristic of the charging parameter gradient. The measurement parameter is compared with a measurement parameter threshold value, and a disturbance of the charging process is inferred if the measurement parameter exceeds the measurement parameter threshold value.

[0103] The measured parameter here is the voltage drop U in volts (V) due to an inductance. The measurement parameter threshold is a voltage limit U. max Used in volts (V).

[0104] Diagram a) of Fig. 5 is identical to diagram a) of Fig. 4. Here too, at the fault time tS, a short circuit occurs in the power supply device 1 and the charging current I rises sharply.

[0105] Diagram b) shows the time course of the decreasing voltage U in volts (V) over time t in seconds. It can be seen that the decreasing voltage U between times t0 and t1 is initially smaller than the measurement parameter threshold U. max From time t1 onwards, the falling voltage U is initially zero because the power supply device 1 is charged with a constant charging current I and the induced voltage U is also zero when the charging current gradient dI / dt is zero.

[0106] At the time of the disturbance tS, the falling voltage U rises abruptly and almost vertically, and usually exceeds the measurement parameter threshold U within a few microseconds. max, which suggests a problem with the charging process. This is also done as in Fig. 4. The emergency measure is carried out by interrupting the power circuit 9 of the power electronics 3 of the power supply device 1. Even with indirect detection, the power circuit 9 of the power electronics 3 can be interrupted so quickly that the fuse of the energy storage device 2 is not exposed to the disturbance of the charging process, and in particular, the fuse is not tripped. If the energy storage device 2 is a battery of an electric vehicle, the electric vehicle would also remain functional.

Claims

[1] Method for operating an electrical power supply device (1) for unidirectional or bidirectional charging of an energy storage device (2), wherein - during a charging process, a temporal charging parameter gradient of a charging parameter characteristic of the charging process is recorded, wherein, - if a disturbance in the charging process is inferred from the detected charging parameter gradient, an emergency measure is taken to protect the power supply device (1) and / or the energy storage device (2) from damage. [2] Method according to claim (1), wherein the charging parameter gradient - is directly detected, whereby the charging parameter gradient is compared with a predetermined gradient threshold, whereby a disturbance of the charging process is inferred if the detected charging parameter gradient exceeds the predetermined gradient threshold, or - is indirectly detected by measuring a measurement parameter characteristic of the charging parameter gradient, and comparing the measurement parameter with a predetermined measurement parameter threshold, concluding that a disturbance of the charging process exists if the measurement parameter exceeds the predetermined measurement parameter threshold. [3] Method according to one of the preceding claims, wherein as an emergency measure a power circuit (9) of a power electronics (3), in particular the power supply device (1) or the energy storage device (2), is interrupted. [4] Method according to one of the preceding claims, wherein the charging parameter is at least one charging current quantity selected from a group consisting of: a charging power, a charging current, a charging voltage and a combination of at least two of the aforementioned parameters, wherein optionally a voltage drop across a measuring path due to an inductance is recorded as a measuring parameter. [5] Method according to one of the preceding claims, wherein at least one threshold value, selected from the gradient threshold value and the measurement parameter threshold value, is set depending on a limit charging parameter selected from a group consisting of: a permissible power gradient limit, a permissible power limit, a permissible current gradient limit, a permissible current limit, a permissible voltage gradient limit, a permissible voltage limit and a combination of at least two of the aforementioned limits. [6] Method according to any one of the preceding claims, wherein - the charging parameter gradient and / or the measurement parameter is detected at a line, a charging cable (14) connecting the power supply device (1) to the energy storage device (2), a power electronics (3), an electrical interface (7) and / or at a control device (13) of the power supply device (1). [7] Shutdown control device (5) for a power supply device (1) for unidirectional or bidirectional charging of an energy storage device (2), wherein the shutdown control device (5) is configured to perform a method according to any of the preceding claims. [8] Shutdown control device (5) according to claim 7, wherein - the shutdown control device (5) is configured to be operatively connected to a power circuit (9) of the power supply device (1) and to interrupt the power circuit (9). [9] Shutdown control device (5) according to claim 7 or 8, wherein - the shutdown control device (5) is formed by a control device (13) of the power supply device (1). [10] Power supply device (1) for unidirectional or bidirectional charging of an energy storage device (2), comprising: - a power electronics unit (3) configured to selectively close or open a power circuit (9) for charging the energy storage device (2); - a shutdown control device (5) according to one of claims 7 to 9, and - an electrical interface (7) which is set up to be connected to the energy storage device (2) for charging the energy storage device (2). [11] Power supply device (1) according to claim 10, wherein - the shutdown control device (5) is integrated into a control device (13) of the power supply device (1) or is designed as a control device (13) of the power supply device (1).

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