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CN-121986424-A - Apparatus and method for protecting an LVDC network connected to a device powered by an HVDC network

CN121986424ACN 121986424 ACN121986424 ACN 121986424ACN-121986424-A

Abstract

The invention relates to a protection device (1) for protecting a hybrid electrical apparatus (M) configured to be electrically connected to a LVDC network and to a HVDC network, the protection device (1) comprising a first connector (C1) configured to be connected to the LVDC network, a second connector (C2) configured to be connected to the hybrid electrical apparatus (M), the second connector (C2) being connected to the first connector (C1) by a power line, a third ground connector (C3) connected to the power line at a connection point (CX) by a ground line, the protection device further comprising at least one first diode (D1) mounted in reverse on the ground line between the connection point (CX) and the third ground connector (C3), and at least one first fuse (F1) mounted on the power line between the connection point (CX) and the second connector (C2).

Inventors

  • Fan Shang Sha Peilong
  • Eric Jiyar
  • Let Luc Sozier
  • Guillaume Potter

Assignees

  • 赛峰电气与电源公司

Dates

Publication Date
20260505
Application Date
20241003
Priority Date
20231010

Claims (11)

  1. 1. An electrical architecture comprising a first low voltage direct current network, called LVDC network, and a second high voltage direct current network, called HVDC network, the electrical architecture further comprising at least one electrical device, called hybrid electrical device (M), connected on the one hand to the HVDC network and on the other hand to the LVDC network via a protection device (1), the protection device (1) comprising: -a first connector (C1), the first connector (C1) being connected to the LVDC network; -a second connector (C2), the second connector C2) being connected to the hybrid electrical device (M), the second connector (C2) being connected to the first connector (C1) by a power cord; -a third ground connector (C3), the third ground connector (C3) being connected to the power line at a connection point (CX) by a ground line, the HVDC network having a maximum allowed voltage, the power line and the ground line of the protection device (1) being configured to withstand the maximum voltage of the HVDC network; -at least one first diode (D1), said at least one first diode (D1) being inversely mounted on said ground line between said connection point (CX) and said third ground connector (C3), and -At least one first fuse (F1), said at least one first fuse (F1) being mounted on said power line between said connection point (CX) and said second connector (C2).
  2. 2. The electrical architecture according to claim 1, wherein the protection device (1) comprises a second diode (D2), the second diode (D2) being mounted on the power line between the second connector (C2) and the connection point (CX).
  3. 3. The electrical architecture of claim 2, wherein the HVDC network has a maximum allowed voltage and the second diode (D2) has a threshold voltage greater than the maximum allowed voltage.
  4. 4. An electrical architecture according to any one of claims 1 to 3, wherein the protection device (1) comprises a second fuse (F2), the second fuse (F2) being mounted on the power line between the first connector (C1) and the connection point (CX).
  5. 5. The electrical architecture according to any one of claims 1 to 4, wherein the protection device (1) comprises an electronic switch (11), the electronic switch (11) being located on the power line between the first connector (C1) and the connection point (CX).
  6. 6. The electrical architecture according to claim 6, wherein the electronic switch (11) is a semiconductor of the MOSFET type.
  7. 7. The electrical architecture of any of claims 6 to 7, wherein the electronic switch (11) is controlled by a control unit (12), the control unit (12) being configured to detect a current on the ground line.
  8. 8. An aircraft comprising at least one electrical architecture according to any one of claims 1 to 7.
  9. 9. A method for protecting an electrical architecture according to any one of claims 1 to 7, the protection device (1) comprising an electronic switch (11), the electronic switch (11) being located on the power line between the first connector (C1) and the connection point (CX), there being an electrical fault (A1) caused by the HVDC network between the second connector (C2) and the third ground connector (C3), and the electrical fault injecting a fault current (I1) to the third ground connector (C3), the method comprising the steps of: -detecting said fault current (I1) in said ground line, and -Controlling the opening of the electronic switch (11).
  10. 10. Method for protecting an electrical architecture according to any one of claims 1 to 7, there being an electrical fault (A1) caused by the HVDC network between the second connector (C2) and the third ground connector (C3), and the electrical fault injecting a fault current (I1) to the third ground connector (C3), the method comprising the steps of: -passing said fault current (I1) through said first diode (D1) and said first fuse (F1) in sequence, so as to form a current loop, and subsequently -Opening the first fuse (F1) under the effect of the fault current (I1).
  11. 11. The method for protecting an electrical architecture according to any one of claims 1 to 7, the protection device (1) comprising a second diode (D2), the second diode (D2) being mounted on the power line between the second connector (C2) and the connection point (CX), there being an electrical fault (A2) caused by the HVDC network between the third ground connector (C3) and the second connector (C2), and the electrical fault (A2) applying an interference voltage (v+) to the second connector (C2), the method comprising the step of blocking the power line by the second diode (D2) as long as the electrical fault (A2) is present.

Description

Apparatus and method for protecting an LVDC network connected to a device powered by an HVDC network Technical Field The present invention relates to the field of electrical architecture for electric or hybrid propulsion aircraft. The electric motors and electrical devices contributing to the electric propulsion function (requiring significant electric power of the order of one hundred kilowatts to one megawatt) are powered by a high voltage direct current grid called HVDC (high voltage direct current) dedicated to the power supply. Furthermore, electrical devices often need to be powered by a Low Voltage Direct Current (LVDC) grid. The invention relates more particularly to the electrical protection of LVDC networks with respect to HVDC networks. Climate change is a major concern for many legislation and regulatory authorities worldwide. Indeed, various restrictions have been, are being or are about to be taken for carbon emissions. In particular, a stringent standard is applicable both to new aircraft and to active aircraft, requiring implementation of technical solutions that make them compliant with current regulations. For many years, the civil aviation field has been working on climate change. Technological research work has led to very significant improvements in the environmental performance of aircraft. The applicant has considered the influencing factors of all design and development phases in order to obtain aeronautical elements and products with lower energy consumption, more environmental friendliness and moderate environmental impact in terms of integration and use in the civil aviation field, aimed at improving the energy efficiency of the aircraft. Accordingly, registrants are continually striving to minimize greenhouse gas emissions by employing benign development and manufacturing methods and processes, thereby reducing their adverse effects on climate and reducing their business' environmental footprint. This ongoing research and development effort has been directed to new generation aircraft engines, device weight reduction (in particular, by the materials used and lighter onboard devices), development of propulsion power technology, and aviation biofuels as an essential supplement to technological advances. Referring to fig. 1, an aircraft is known in the prior art, which comprises an LVDC network (e.g. 28 Vdc) allowing to power several devices E1 to E4, such as electric actuators, flight controls, radio and navigation computers, etc. The LVDC network comprises at least a first S BT source, in particular a low-voltage source, which supplies the BUS voltage BUS in order to supply several devices E1 to E4. A main switch 2 is provided between the devices E1 to E4 and the voltage BUS in order to isolate the devices E1 to E4 in case of a short circuit. Still referring to fig. 1, the aircraft includes at least one HVDC network (e.g., between 800Vdc and 1500 Vdc) that allows for powering several high voltage devices. The HVDC network comprises at least one second source S HT, in particular a generator. In a known manner, the aircraft comprises so-called "hybrid" electrical devices, such as electric propulsion engines M, which are connected on the one hand to the LVDC network, for example, in order to receive control instructions, and on the other hand to the HVDC network, in order to receive the electric power required for propulsion. For example, see fig. 2, in a known manner, the propulsion motor M comprises a power section 90 connected to the HVDC network for the purpose of modulating the electric power by means of a power converter, a control inverter or the like. The propulsion motor M further comprises a control portion 91 configured to exchange electrical signals (MLI, etc.) with the power portion 90. In a known manner, the propulsion motor M comprises one or two electrical isolation barriers 92 between two networks LVDC, HVDC. Referring to fig. 3, if a short circuit fault occurs within the power section 90, an arc a may occur. It is instantaneously supplied with electrical energy from E HVDC from the HVDC network for several milliseconds to several hundred milliseconds. This time period allows HVDC network protection to alleviate faults by short circuit or overload protection. The arc a may also be powered by rotational kinetic energy E CIN or wind effects. The magnitude of the fault current and voltage may be thousands of amperes and up to thousands of volts, respectively. Under these conditions, the arc a will produce a very broad plasma, which may extend for tens of centimeters. Thus, all portions 90, 91 of motor M are immersed in arc a. In particular, see [ fig. 4], the HVDC network is then connected to the LVDC network by means of an arc a. If arc a is considered to be the sum of the fundamental voltages, a potential difference may occur between the two rails of the LVDC network. In the example of [ FIG. 4], arc A is in contact with the 0Vdc rail and the 28Vdc rail. Thus, a large