Power electronic system

Abstract

Power electronic system (10), characterized by the following features: - the system (10) comprises a coolant distributor (11), a coolant connection (12), electrically active parts (13, 14), namely power electronics (13) and a terminal box (14), a subrack manufactured in accordance with the standard for 19" components EIA 310-D, IEC 60297 and DIN 41494 SC48D, which supports the active parts (13, 14) and at least one sensor (15) attached to the subrack and arranged below the power electronics (13) and the terminal box for measuring a water level within the system (10), - the coolant connection (12) connects the coolant distributor (11) fluidically to the power electronics (13) and - the system (10) is configured such that the system (10) automatically shuts down and informs a backend of a possible flood when the sensor (15) detects the water level.

Description

[0001] The present invention relates to a power electronic system. State of the art

[0002] In electrical engineering, a charging station is any stationary device or electrical system 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 having to remove the energy storage device—such as 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.

[0003] Particularly well-known here are high-performance DC fast charging (HPC) systems according to IEC 61851-23, such as the combined charging system (CCS) widely used in Europe. In standard DC charging, direct current from the charging station is fed directly into the vehicle. This is supplied by a high-performance rectifier from the power grid or by large buffer batteries at solar charging stations. Buffer batteries can also be connected locally to the grid operator's power grid to stabilize the electricity supply. The vehicle typically has an on-board charger (OBC) control unit. This communicates with the charging station and the battery management system.

[0004] Since the DC connections of the charging station are directly connected to the corresponding connections of the traction battery, high charging currents can be transmitted with minimal loss, enabling short charging times. However, this also requires considerable power output from the electronics. Therefore, a circuit breaker is typically triggered as a flood protection measure; the system then shuts down.

[0005] DE 10 2012 224 457 A1 discloses a battery pack arrangement with a water accumulation detection device within an installation area and a waterproof housing, which is installed on the bottom surface of the device and arranged with the battery pack therein, wherein the device comprises a base part with a water inlet opening through which water that has accumulated in the installation area flows in, a float which is set afloat by the buoyancy of the water flowing into the base part, a switching unit which creates an electrical connection when the float rises to or below a predetermined height, and an elastic link which connects the float and the bottom surface of the base part, so that the float is in a predetermined position when the buoyancy of the water does not affect the float.

[0006] Document CN 2 06 250 801 U discloses an electric vehicle charging station with a flood protection safety mechanism. The core of the disclosure is an integrated water level sensor that detects when water enters the housing. If a critical level is exceeded, a control unit automatically interrupts the power supply to prevent electric shocks to users and passersby.

[0007] WO 2013 / 158 463 A1, US 9 363 103 B2 and US 2011 / 0 127 945 A1 represent further state of the art. Disclosure of the invention

[0008] The invention provides a power electronic system according to claim 1.

[0009] The proposed approach recognizes the need for flood detection, enabling, for example, the shutdown of the system or feedback to the backend of the appropriately equipped charging station. Service personnel can thus be informed of the water level in advance, and the system can be safely shut down. This proposed fault detection therefore opens up a wide range of preventative measures.

[0010] The advantage of such an early safety shutdown lies in the improved prevention with regard to flooding, in order to prevent damage or even defect of individual subcomponents, as well as to inform service employees and charging park operators about the condition of the affected charging point.

[0011] Further advantageous embodiments of the invention are specified in the dependent patent claims. Brief description of the drawings

[0012] An embodiment of the invention is shown in the drawings and is described in more detail below. Fig. Figure 1 shows a power electronic system according to the invention. Fig. 2 and Fig. Figure 3 shows an exemplary embodiment of a float switch as a changeover switch. Embodiments of the invention

[0013] Fig. Figure 1 illustrates a system (10) whose rack, in accordance with the so-called 19-inch rack standardized in EIA 310-D, IEC 60297 and DIN 41494 SC48D, has a width of 48.26 cm. This frame, in turn, supports four power electronic modules (13) and a terminal box (14). A coolant distributor (11) of the system (10) is fluidly connected to the power electronics (13) via corresponding coolant connections (12) to prevent overheating.

[0014] It is understood that the subrack may contain other electrically active parts (13, 14) instead or additionally, without departing from the scope of the invention. In the present context, an active part is understood to be any electrically conductive part that is intended to be live during normal operation, in accordance with VDE 0140-1:2007-03. This includes, in particular, "dangerous live parts (13, 14)" within the meaning of the aforementioned standard, from which there is a risk of electric shock.

[0015] However, one or more measuring sensors (15) arranged below the power electronics (13) and the terminal box (14) prove to be essential to the invention, and these sensors are shown here as having an exemplary form as described in Fig. The system assumes the presence of the float switch (15) shown in the diagram. As soon as the sensors (15) detect a dangerous water level within the system (10), the potential rise of which could lead to the immersion of the active parts (13, 14), the system (10) automatically shuts down and informs the backend of the possible flood.

[0016] The float switches or other changeover switches (15) use the following method: Fig. The operating principle is illustrated in section 3: When an electrical voltage is applied to the first pole (BK), a test current flows, depending on the water level, either via the second pole (BN) or via the third pole (BU). In this embodiment, the voltage is dimensioned such that the resulting test current is 20 mA, taking into account the characteristics of the changeover switch (15) and its internal resistances. The test current can, for example, also be lower.

[0017] In an alternative embodiment, for example, a broken finger level switch can be used; measurement by ultrasound is also conceivable. Furthermore, it should be noted that the color coding chosen here according to IEC 757 is merely an example.

Claims

[1] Power electronic system (10), characterized by the following characteristics: - the system (10) comprises a coolant distributor (11), a coolant connection (12), electrically active parts (13, 14), namely power electronics (13) and a terminal box (14), a subrack manufactured in accordance with the standard for 19" components EIA 310-D, IEC 60297 and DIN 41494 SC48D, which supports the active parts (13, 14) and at least one sensor (15) attached to the subrack and arranged below the power electronics (13) and the terminal box for measuring a water level within the system (10), - the coolant connection (12) connects the coolant distributor (11) fluidically to the power electronics (13) and - the system (10) is configured such that the system (10) automatically shuts down and informs a backend of a possible flood when the sensor (15) detects the water level. [2] Power electronic system (10) according to claim 1, characterized by the following characteristic: - the sensor (15) includes a changeover switch (15). [3] Power electronic system (10) according to claim 2, characterized by the following characteristic: - the changeover switch (15) is a float switch (15). [4] Power electronic system (10) according to claim 2 or 3, characterized by the following characteristics: - the changeover switch (15) has a first pole (BK), a second pole (BN) and a third pole (BU) and - the changeover switch (15) is configured such that when an electrical voltage is applied to the first pole (BK), a test current flows either via the second pole (BN) or via the third pole (BU), depending on the water level. [5] Power electronic system (10) according to claim 4, characterized by the following characteristic: - the voltage is dimensioned according to the changeover switch (15) such that the test current has a magnitude of 20 mA. [6] Power electronic system (10) according to any one of claims 1 to 5, characterized by the following characteristic: - the measuring sensor (15) is an ultrasonic sensor.

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