EP3787922A1

EP3787922A1 - High-speed discharge system for a high-voltage energy store

Info

Publication number: EP3787922A1
Application number: EP19720532.1A
Authority: EP
Inventors: Sebastian UTZ
Original assignee: Innofas GmbH
Current assignee: Innofas GmbH
Priority date: 2018-05-03
Filing date: 2019-04-25
Publication date: 2021-03-10
Also published as: WO2019211172A1; DE102018110621A1

Abstract

The invention relates to a high-speed discharge system (1) for discharging a high-voltage energy store (10) via a grid connection (N) into a power grid as far as a certain residual charge (SOC) of the charging capacity, comprising an alternator (20) which is connected on the grid side and can be connected or is connected via a connection line (2) to a junction box (61) which is arranged on or in the high-voltage energy store (10), and while the high-voltage discharge system (1) is operating an intermediate circuit voltage U_ZK is present between the alternator (20) and the high-voltage energy store (10), wherein in addition a control device (30) is provided which during the discharge process ensures that the intermediate circuit voltage U_ZK is higher than the peak value of the power grid alternating voltage U_grid of the power grid.

Description

High-speed discharge system for one

High-voltage energy storage

Description:

The invention relates to a discharge system for a high voltage source.

This disclosure relates to electrically powered vehicles, and more particularly, but not exclusively, to a discharge device for a high voltage power storage device for selectively discharging energy stored in a high voltage power source of an electrically operated vehicle. Hybrid electric vehicles (HEVs), plug-in hybrid electric vehicles (PHEVs), battery electric vehicles (BEVs), fuel cell vehicles, and other well-known electric vehicles from conventional motor vehicles in that they are powered by one or more electric machines (ie, electric motors and generators) instead of or in addition to an internal combustion engine. The supply of high voltage power for powering these types of electric machines is typically accomplished by a traction battery system having one or more battery cells that store energy. Increasingly, so-called high-voltage memory cells are used whose operating voltage is well above 48V, eg at 650 V.

In the development of electric vehicles not only the range plays an important role, but also the charging equipment. Today's electric and hybrid vehicles have a charging cable as standard, which supplies the vehicle's own charger with electrical energy. In the future, inductive charging will be increasingly used via a base plate with a primary coil and a secondary coil installed in the vehicle. In order to be able to apply these technologies at a mature level, numerous charging tests are necessary during the development. Since the capacity of the batteries is limited, attempts must be regularly interrupted to time-consuming to discharge the high-voltage memory.

As a result, in electrical and other tests on test benches and for other examinations, it is always necessary to discharge the high-voltage source in a targeted and rapid manner.

The discharge of a high-voltage battery can, for. B. by activating all electrical consumers, such as interior heating, air conditioning ge, heated rear window, headlights and heated seats. Here, power of a few kilowatts flow. For hybrid vehicles with low battery capacity, the unloading process takes about three hours. Pure electric vehicles with energy contents of up to 100 kWh would take about a day to complete.

In practice, for. B. vehicles to be tested or test drive vehicles operated by a driver as long as on the road or on a test track d. H. driven until the desired discharge state has occurred. In such test vehicles, which may be moved open on the road, the Messverkabe must be removed at each discharge and reconnected after returning. Vehicles that have an inductive charging system must be repositioned in the test bench at the previous position with millimeter precision in order to obtain the same test conditions. The disadvantage is not only the fact that this process is zeitaufwen dig and expensive, but also each of the energy stored in the battery cell must be wasted useless.

In the prior art discharge devices for batteries are known to discharge batteries. From DE 10 2014 224 779 A1 is z. B. a solution is known in which a sensor is provided which is designed so that it detects egg nen parameter of a high voltage source and a controller in communication with the sensor and a discharge circuit, which energy stored in the high voltage source, in response to a command signal from the controller discharges. For this purpose, the discharge circuit comprises a plurality of resistors which are connected in parallel with one another. Such and similar known solutions are, but not suitable, a vehicle battery with a charging capacity between 20 KW and 50KW or greater (at a typical operating voltage between 300V and 450V to partly 1000V). sufficiently fast to discharge. So that at a battery voltage of z. B. 300 V still a desired power of 50 kW can be achieved should a high-voltage discharge component with currents of up to about 175 A can discharge. The invention is therefore an object of the invention overcome above-mentioned disadvantages and to propose a solution for a test stand for cost-effective, fast and efficient unloading of a high voltage energy storage, the

This object is achieved by the feature combination according to claim 1.

According to the invention, a high-speed discharge system is proposed for discharging a high-voltage energy store via a grid connection into a conventional power grid up to a certain residual charge (SOC) of the charging capacity, comprising a grid-side connected inverter which is connected via a connecting line to a junction box arranged on or in the high-voltage energy store can be connected or connected and during operation of the high-speed discharge between the inverter and the high-voltage energy storage an intermediate circuit voltage U _Z K is applied, further comprising a control device is provided, which ensures during the discharge that the intermediate circuit voltage U _{ZK is} greater than the peak value of the network change - Voltage U _Ne tz of the power grid. Such a solution can be integrated with advantage in a control cabinet having a test stand or be connected to it. In an advantageous embodiment of the invention it is provided that the

Control device comprises a transformer which is netzspannungssei tig between the inverter and the power supply, said transformer having a transmission ratio to the output voltage U _Ne tz_neu at the inverter to at least the mains voltage U _Ne tz raise, in the event that the voltage U _{Netz-neu is} lower than that of the mains voltage U _Ne tz ·

In the discharge mode, the inverter works unloading by not drawing the energy from the mains, but taking it from the high-voltage battery and feeding it into the grid. Due to the high battery capacity of a high voltage energy storage device, the battery voltage remains almost stable throughout the discharge until the SOC of the battery, which could increase the current flow to values higher than 100A, but this is prevented by current limiting.

The minimum possible intermediate circuit voltage must be above the peak value of the mains voltage. Since the vehicle test stand must be able to discharge the vehicle battery to a customer SOC of 0%, achieving a minimum DC link voltage is absolutely necessary. The term SOC stands for "State of charge" and describes the state of charge of the vehicle battery in percent. Due to the prevailing mains voltage, which is currently typically above the minimum DC link voltage, the aforementioned transformer is required.

In an alternative embodiment, it may also be provided that a DC / AC feed is not performed, but specifically a DC / DC feed via a converter unit in order to store the electrical energy in a buffer memory. It is further preferred to provide a device with a switching branch in order to be able to use both discharge options and preferably to switch the discharge path to the buffer reservoir and / or the mains connection by means of a controller. In a particularly advantageous embodiment of the invention it is provided that a zero-current control is realized. In this case, the control is designed in such a way that, as far as possible, no feedback, ie "zero" current, flows into the network, but rather the power supply. as long as self-consumption is possible, fed into the "own" network to the consumers, or preferred for charging reserves

Discharge process is used to load the DC buffer. For this purpose, the controller can make a targeted current flow regulation by the user in accordance with an individually selectable prioritization, which further adapts itself dynamically, depending on time variant sizes. For example, the discharge behavior at night tariff times can be controlled differently than at the time of day tariffs, whereby in each case preferably the zero-current control is superimposed as a control loop. In an advantageous embodiment of the invention, it is provided that fer ner mains voltage side in the connection between the inverter and the power connection, a combination filter and preferably still a line filter are arranged for filtering high-frequency voltage disturbances, the combined filter further preferably comprises a throttle. Another aspect of the present invention relates to the fact that the high-voltage energy storage is installed in a vehicle at its intended in accordance installation location.

The cables of the PTC interior heating and of the electric air conditioning compressor (EKK) are too weakly dimensioned for connection. No energy can be drawn from the AC charging socket (LD), as the on-board charger (OBC) can supply power to the high-voltage battery but can not operate any consumers via the charging socket. Since a standardized DC charging socket is currently not available on many vehicles, the use of this cable would definitely restrict the compatibility of the high-speed discharge system. The

Traction cables between power electronics (LE) are subjected to AC voltage, so that here too no suitable connection to the high-voltage battery can be created. According to the invention thus comprises the high-speed discharge system in a preferred embodiment, a cable set comprising the connec tion line and two breakout boxes. The first breakout box is provided with a connector for connecting the connection cable to the vehicle's junction box. Furthermore, the connection line of the first breakout box extends into the second breakout box, from where a detachable connection line leads as part of the cable set to the control cabinet or inverter.

In a particularly advantageous embodiment, it is provided that in the second breakout box three cable pairs of the cable set from each of a high-voltage lines (HV +) and a high-voltage lines (HV) run, in each case the high-voltage lines (HV +) and the high-voltage lines (HV-) via a common Busbar (71 and 72) are electrically connected to each other. A line pair leads (out of the breakout box) to egg nem attached to the breakout box connector (housing connector), which provides the interface for connecting the circuit to the inverter with the inverter.

Another line pair (HV +, HV-) is led out through cable bushings from the second breakout box for connection to the power electronics (LE) of the vehicle. By a previously described (partly separable as intended via connectors) cable set of connecting lines and the two breakout boxes, a United bond and thus releasable connection line between the inverter and the built-in vehicle high-voltage energy storage can be realized.

In a further advantageous embodiment of the invention, it is provided that the first and second breakout boxes each have a metallic in particular shielded housing, which are connected to a common equipotential bonding line (PE), which leads to the connector for connecting the inverter to the connection of a connection line to the inverter at the same time establish a connection to an external equipotential bonding.

In order to further ensure safe operation during the discharge process, it must be ensured that no unintentional disconnection of the detachable connection to the inverter is possible while z. B. an arc could be ignited.

According to the invention, it is proposed in an advantageous embodiment for this purpose that a mechanical unlocking and locking device is provided on the second breakout box, which is designed such that a locking bracket (for locking the plug connection) is provided which is in a position when the plug connection is locked With an inserted mating connector, a position switch in the breakout box is operated directly or indirectly. An actuating tappet for the position switch can be arranged in the direction of actuation behind the locking bracket, so that it is actuated when the shutter is opened. The position switch is used to realize a break contact with double break, which safely disconnects the emergency stop circuit.

The vehicle test bench is advantageously implemented in such a way that a control cabinet is provided in which the inverter is accommodated and leads a line to the mains connection of a three-phase network (L1, L2, L3).

Another aspect of the present invention relates to a method of discharging a high voltage energy storage in a vehicle having a high speed discharge system as described above. In an advantageous embodiment of the invention, it is provided that after connecting the high-voltage energy storage device to the inverter (or the vehicle test bench) via the pluggable connection line the driving readiness of the vehicle is produced directly or via a manipulation of the vehicle control unit and then the unloading process is started.

The preparation of the driving readiness is necessary insofar as a discharge is even permitted by the on-board electronics of a vehicle. An initially obvious possibility for producing the unloading readiness is to activate the ignition of the vehicle by means of the start / stop button. The signal from the on-board power supply control unit is read in, which closes the corresponding relay. If the gateway is supplied with power, the HVK causes the high-voltage contactors to close. However, in order to save the 12 V starter battery, the terminal is automatically deactivated again after a few minutes. This has the consequence that the contactors open and the unloading process is interrupted. Thus, this variant is unsuitable for discharging a high-voltage battery.

According to the idea of the present invention, this works

High-speed discharge system after closing the corresponding contactors by not only pressing the Start / Stop button, but also the brake is applied by a PLC. Furthermore, by targeted manipulation of the vehicle control unit, the state "driving readiness" can be prepared or simulated accordingly

When unloading a high-voltage battery, on the one hand, the actual voltage is read out and displayed on the display of the test stand. On the other hand, the SOC is monitored. When unloading the unloading process must be finished at 0% at the latest, whereby

Energy is stored in the battery. Furthermore, the battery current is monitored. Here, a parameter determines the amount of current that may flow permanently, without the battery management system having a Reduction of the current flow causes.

Since when discharging a high-voltage battery, the energy does not flow through the power electronics and thus on the vehicle side can not be controlled by the Leistungselekt ronik, this task must by the

High-speed discharge system or the test stand taken over who. To stay within the limits, the actual discharge current should never be higher than the maximum setpoint.

The limit and measured values of the battery management system are communicated via a CAN bus and thus made available to all bus users. So that no further line from the test bed to the vehicle to be unloaded must be performed, the CAN communication should be carried out in an advantageous manner by radio transmission. For this purpose, a transmitter and a receiver module are used, wherein the transmitter is connected to the vehicle and supplied from the 12 V starter battery. The receiver is connected to the PLC via CAN cables at the test bench.

Other advantageous developments of the invention are characterized in the Unteransprü Chen or will be described in more detail below together with the description of the preferred embodiment of the invention with reference to FIGS. Show it:

1 is a schematic representation of an embodiment egg nes high-speed discharge system,

Fig. 2 is an illustration of the voltage level between the high

voltage energy storage according to Figure 1 and the Netzan- conclusion;

3 shows a cable set for connecting the high-voltage energy supply chers with the inverter and the power electronics;

4 shows a schematic partial view of a vehicle with a part of the components of the fluid speed ignition system;

5 is a schematic view of components for Fiersteilung the vehicle operational readiness for a discharge;

6 shows a schematic view of a wiring of the inverter in the control cabinet;

Fig. 7 is a flowchart for explaining the unloading process; 8 shows an exemplary voltage profile during the discharge process and

9 shows an exemplary current profile during the discharge process.

In the following, the invention will be explained in more detail with reference to FIGS. 1 to 9 on the basis of exemplary embodiments, wherein the same reference numbers refer to the same structural and / or functional features.

FIG. 1 shows a schematic representation of an embodiment of a high-speed discharge system 1

High-speed discharge system 1 is designed for discharging a floating-voltage energy storage device 10 via a network connection N into a public or private power grid up to a specific residual charge SOC of the charging capacity. The SOC is a value specified by the manufacturer up to which a battery cell or energy cell should be discharged to the maximum in order to ensure a long service life.

The high-speed discharge system 1 comprises an inverter 20 which is connected to the grid and which can be connected or connected via a connecting line 2 to a junction box 61 (as shown by way of example in FIG. 4) arranged on or in the high-voltage energy store 10. Furthermore, mains voltage side in the connection between the inverter 20 and the power connection N, a combi filter 40, a mains filter 50, a choke 51 and a transformer 30 are arranged. The filters and the choke are used to filter out high-frequency voltage fluctuations and current peaks.

During operation of the high-speed discharge system 1, an intermediate circuit voltage UZK is applied between the inverter 20 and the high-voltage energy store 10, wherein a control device 30 is also provided which ensures during the discharging process that the intermediate circuit voltage UZK is greater than the peak value of the network change voltage U. _{Network of} the electricity network is.

Flierzu is, as shown in the figure 2, the transformer 30 is provided, the mains voltage side between the inverter 20 and a Netzan circuit N is arranged, the transformer 30 has a gear ratio to the output voltage U _Ne t _z _neu at the inverter 20th to at least the mains voltage U _Ne t _z , in the event that the voltage U _Ne tz_ _n eu is lower than that of the mains voltage U _Ne tz ·

In the present example, this is as follows. Since the test stand must be able to discharge the vehicle battery to a customer SOC of 0%, it is necessary to achieve a minimum DC link voltage of 300V. The output voltage at the inverter of 180 V on the AC side is as follows. Due to a mains voltage of 400 V, the minimum intermediate circuit voltage must be higher than the peak value of the mains voltage. In addition, a five percent control reserve and possible voltage fluctuations on the grid of 10% are to be taken into account with advantage. This results in:

UZK min - U network new V2 1, 15 Resolved according to U _Ne tz_neu, the maximum possible mains voltage and thus the transformation ratio ü of the transformer can be determined.

ÜNetz_neu ^- 184 V

In order to reach the secondary voltage of 400 V required by the mains side at a primary voltage of 184 V, a gear ratio of 0.46 is necessary. In order to be able to do without a custom-made product, a commercially available transformer with a nearby ratio of = = 0.45 is procured.

ÜNetz_neu ⁼ ÜNetz Ü = 400 V 0.45 = 180 V This results in an output voltage at the inverter of 180 V.

The output currents to the inverter in the present case in the game 155 A, while the transformer 31 feeds through the transmission ratio 70 A in the network N. Thus, the high voltage energy storage 10 is discharged with a power of up to 48 kW. With reference to FIGS. 3 and 4, it is shown how the cable set according to the invention is designed to connect the high-voltage energy store 10 to the inverter 20 and the power electronics LE.

The cable set comprises a first and a second breakout box 60, 70 respectively connected to the connection line 2. The breakout box 60 is equipped with a connection 63 for connecting the connection line 2 to the junction box 61. The first breakout box 60 is connected to the second breakout box 70 via the lines 2 of the line pair HV + and HV-.

In the second breakout box 70, three pairs of lines each consisting of a high-voltage line HV + and a high-voltage line HV- are provided, wherein on the one hand the three high-voltage lines HV + and on the other hand the three high-voltage lines HV- via a common busbar 71 and 72 with each other are electrically connected. Each busbar 71, 72 is electrically isolated from the other busbar and from the housing.

A line pair HV +, HV- leads to a connector 73 attached to the breakout box 70, which establishes the interface for connecting the connection line 2 to the inverter 20.

Another line pair HV +, HV- leads out through cable bushings from the second breakout box 70 and indeed for connection to the power electronics LE of the vehicle, as is shown schematically in FIG. The first and second breakout boxes 60, 70 each have a metallic, in particular shielded housing 65, 75, which are connected to a common equipotential bonding PE, which leads to the connector 73 and from there to the not shown in detail control cabinet of the vehicle. When connecting the connection line to the inverter 20 so that at the same time a connection to an external equipotential bonding is established.

FIG. 3 also shows a mechanical unlocking and locking device 80, namely at the second breakout box 70. The latter is designed such that a locking bow 73a of the plug connector 73 is in a position for locking the plug connection with an inserted mating plug 74 (FIG. which is connected to the connecting line to the inverter or control cabinet), a position switch 81 in Breakoutbox indirectly or directly operated. This makes it possible to ensure that an unlocking lock can be realized in a simple and cost-effective manner. If an operator would like to release the mating connector 74 from the plug-in connector 73 under load, this would already occur when opening the connector. locking bracket 73a of the position switch 81 is actuated and the load path un interrupted. A plunger of the position switch 81 is for this purpose outside of the breakout box 70 in order to interact with the bracket in the direction of actuation co. FIG. 5 shows a schematic view of components for establishing a possibility of vehicle operational readiness for a discharge process. The preparation of the unloading readiness is to activate the ignition of the vehicle. The signal of the start / stop button is read in by the onboard supply control unit, which closes the relay at terminal 15. If the gateway is supplied with voltage, closing of the high-voltage contactors is initiated. However, not only is the actuation of the start / stop button initiated, but also the actuation of the brake is controlled by a PLC. In the general part of the description of the invention, another way is explained to prepare the vehicle operational readiness for a discharge.

FIG. 5 schematically shows the course of the load path in the control cabinet of the vehicle test stand. In this a switch-disconnector is installed, which is operated by a built-in lever in the door.

In addition to the fuses designated F1 to F5, contactors are connected in the load path. After the 100 A fuses F1 is the

Main contactor. Then follow the line filter, transformer and the combi filter. At the input of the mains choke, the tap is taken to the pre-charging contactor, which is protected by a 25 A fuse. From there, the terminals L1, L2 and L3 of the inverter are contacted. This contactor only serves to pre-charge the inverter-side DC link. As soon as the set intermediate circuit voltage is reached, the pre-charging contactor is opened and the line contactor is closed. Thus, the inverter is ready for operation. The output of the line choke is via the line contactor with the terminals U, V and W. connected to the inverter. When a high-voltage battery 10 is discharged, the entire current flows from the DC inputs DC +, DV- via the HV lines 2 of the inverter via the terminals U, V and W into the power grid. The DC lines between the inverter 20 and the high-voltage battery 10 are protected against overcurrents by the two 160 A low-voltage high-performance fuses F4 and F5 and can be reliably interrupted by means of the contactors indicated directly above them. The fact that here two contactors are installed, serves the security.

FIG. 7 shows a flow chart of a software support

Unloading process. First of all, however, a parameterization of the

Inverter in a certain operating mode in order not to operate the inverter in the usual basic setting for operation under high overload. Since during dynamic discharging of a high-voltage battery no dynamic changes in the current characteristic are to be expected, the rated current may be increased to the maximum value. In addition, the desired intermediate circuit voltage can be adjusted by setting a parameter.

The DC contactors within the test stand are initially open and the regenerative current limit is set to the minimum achievable value of 3%. This variable controls the discharge capacity. The current battery voltage U _{Batt is} transmitted via the CAN bus and the switching state is set by means of z. B. a Discharge button read via a touch display.

After activation, the preparations for closing the DC contactors are made first. For this, the setpoint DC link voltage is raised to the battery voltage plus 15 V and the inverter is given the controller enable so that it can set the DC link voltage to the desired value. After a waiting period of two seconds, closed the DC contactors. At this point, a timer is necessary because changing the intermediate circuit voltage takes several hundred milliseconds in entitlement. Thereafter, another time delay of two seconds takes place. This prevents the power from being raised while the contactors are closing.

In the next step, the unloading process takes place. The set DC link voltage is set to 280 V. This voltage is chosen because it is above the minimum DC link voltage of 243V but less than the minimum required battery voltage of 300V. It must be ensured that the set DC link voltage is always below the battery voltage so that the inverter can reach the specified current limit. As long as the inverter is operated in its current limit, the intermediate circuit voltage can no longer be acted upon. Permanently queried are several parameters. The state of the Discharge button is required in order to be able to terminate the unloading process manually. The target SOC and the current SOC must be permanently compared therewith, so that the discharge process when reaching the ge desired state of charge of the high-voltage battery 10 is terminated. For the calculation of the discharge power, the battery voltage and the

Discharge current needed. In addition, an operator can choose to unload at maximum power or at lower power. This selection is made via a controller on the touch display and is stored in the variable P_soii_Regier. The variable P_ _e ntiade_berechnet serves as an auxiliary variable. Before the calculated value can be assigned to the parameter regenerative current limit, it must first be checked for plausibility. For a calculated power, which is greater than the maximum allowed 48 kW, the value 100% is stored in the generator current limit parameter. Since values smaller than 3% lead to a malfunction of the inverter, they must never be transmitted. Values between 3% and 100% are unchanged in the parameter for the genera- toric current limit stored.

If the Discharge button is pressed again, or if the current SOC corresponds to the target SOC, the program proceeds to the next step. The

Discharge power is reduced to the minimum value of 3% and the DC link voltage is increased to the current battery voltage plus 15 V. Thus, the inverter operates as a generator and due to the permanently set motor current limit of 0%, the current flow can be reduced to a minimum. After the timer has expired, the DC contactors are opened, the inverter is de-energized and the program can start again from the beginning.

FIG. 8 shows the profile of the mains voltage, the intermediate circuit voltage and the SOC as a function of time. On the course of the DC link voltage, the program flow is particularly easy to recognize. At the time t = 0 s, d. H. When the DC contactors are open, the DC link voltage corresponds to the minimum voltage of 243 V. When the Discharge button is activated, the DC link voltage is increased to 436 V. This value corresponds to the battery voltage plus 15 V. In the next step, the DC contactors are closed. Since the motor current limit is 0% and thus no current flow is permitted, the target DC link voltage of 436 V can not be maintained. The DC link voltage is drawn from the high-voltage battery to its current voltage level. In the next step, the setpoint DC bus voltage is reduced and the regenerative current limit is set to the value of 100%. Due to the high current flow and the internal resistance of the high-voltage battery, the intermediate circuit voltage drops to 408 V. During the

Discharging process decreases the battery voltage in addition to the SOC, until it has reached its minimum voltage of 360 V.

The mains voltage during idle is 403 V and is during the feed-in solution is raised to 405 V in order to be able to achieve a current flow in the line direction.

With renewed activation of the Discharge-buttons, or as in this case, on reaching the target ^SOC's of 0%, the current limit is set to 3%, and raised again the intermediate circuit voltage to 15 V. After a waiting time of 2 s, the DC contactors are opened. After that, the inverter-side intermediate circuit voltage drops back to its minimum value of 243 V.

FIG. 9 shows the discharge currents and the discharge capacities as a function of time. It can be seen here that, despite a constant DC link current l _z, the current on the 400 V mains side l _Ne tz decreases slowly. This is the effect of decreasing battery voltage. With constant mains voltage and decreasing discharge power, the level of current I _Net2 must therefore decrease. As soon as the discharge current is limited by the battery management system, a clear decrease of the discharge power PZK and consequently also P _Ne tz can be seen.

The invention is not limited in its execution to the above-mentioned preferred embodiments. Rather, a number of variants is conceivable, which makes use of the illustrated solution even with fundamentally different types of use.

Claims

claims

A high-speed discharge system (1) for discharging a high-voltage energy storage device (10) via a network connection (N) into a power grid up to a certain residual charge (SOC) of the charging capacity, including a grid-side connected inverter

(20), which is connectable or connected via a connecting line (2) to a high-voltage energy store (10) or junction box (61) and in the operation of the

High-speed discharge system (1) between the inverter (20) and the high-voltage energy storage (10) an intermediate circuit voltage UZK is applied, further comprising a control device

(30) is provided, which ensures during the discharge process, that the intermediate circuit voltage U _Z K is greater than the peak value of the AC line voltage U _Ne tz of the power grid. 2. High-speed discharge system (1) according to claim 1, characterized in that the control device is a transformer

(31), the mains voltage side between the inverter (20) and a network connection (N) is arranged, wherein the transformer (31) has a transmission ratio to the output voltage Ü _{net new} at the inverter (20) to at least the network - Voltage U ^ _{tz increase} , in case the voltage Ü _{Netz-neu is} lower than the mains voltage Ü _Netz -

3. high-speed discharge system (1) according to claim 1 or 2, characterized in that further on the line voltage side in the connection between the inverter (20) and the mains connection (N) a combination filter (40) and preferably still a net filter (50) are, to filter out high-frequency voltage disturbances.

4. High-speed discharge system (1) according to claim 3, characterized in that the combined filter (50) comprises a throttle (51).

5. High-speed discharge system (1) according to one of the preceding claims, characterized in that the high-voltage energy storage device (10) is installed in a vehicle (F) at its intended installation location.

6. High-speed discharge system (1) according to one of the preceding claims, characterized in that the connection line (2) is provided with a first breakout box (60) with a connection for connecting the connection line (2) to the junction

Box (61) and the connecting line (2) of the first breakout box (60) in a second breakout box (70).

7. high-speed discharge system (1) according to claim 6, characterized in that in the second breakout box (70) three line pairs each consisting of a high-voltage lines (HV +) and a high-voltage lines (HV-) run, in each case the high-voltage lines (HV +) and the High-voltage lines (HV-) via a common busbar (71 or 72) are electrically connected to each other, wherein a Lei line pair to a on the Breakoutbox (70) mounted connector (73) leads, which is the interface for connecting the connecting cable with the Inverter (20) manufactures.

8. high-speed discharge system (1) according to claim 6 or 7, characterized in that a line pair (HV +, FIV-) by Ka bushings from the second breakout box (70) are led out for connection to the power electronics (LE) of the vehicle.

9. high-speed discharge system (1) according to claim 7 or 8, characterized in that the first and second breakout boxes (60, 70) each have a metallic, in particular shielded housing (65, 75), which are connected to a common equipotential bonding line (PE), which leads to the plug connector (73), at the same time a connection when connecting a connecting line to the inverter (20) to produce an external equipotential bonding.

10. High-speed discharge system (1) according to claim 7, 8 or 9, characterized in that a mechanical unlocking and locking device (80) is provided on the second breakout box, which is formed so that a locking bracket (73 a) in a

Position when locking the connector (73) with a plugged mating connector (74), a position switch (81) in breakout box indirectly or directly operated.

11. High-speed discharge system (1) according to one of the preceding claims, characterized in that a control cabinet

(100) is provided, in which the inverter (20) is housed and a line path (101) to the mains connection (N) of a three-phase network (L1, L2, L3) leads.

12. Fast discharge method for discharging a high voltage energy storage (10) in a vehicle with a

High-speed discharge system (1) according to one of the preceding claims.

13. The method of claim 12, wherein after connecting the high voltage energy storage device (10) to the inverter (20) via a ne equipped with a connector connecting line (2)

Vehicle readiness of the vehicle is made directly or via a Manipula tion of the vehicle control unit and then the

Unloading is started.

14. The method according to claim 12 or 13, characterized in that the discharging process is stopped as soon as a certain desired residual charge (SOC) of the high-voltage energy storage device (10) is reached.