Device and method for detecting an electrical load
A device for detecting an electrical load connected to an electric power supply network. The device comprises means for injecting a test signal into the electrical network and means for identifying the presence and the nature of an electrical load connected to the electrical network on the basis of the test signal.
1. A device for detecting an electrical load connected to an electric power supply network, comprising:
means for injecting a test signal into the electrical network and means for identifying the presence and the nature of an electrical load connected to the electrical network on the basis of the test signal, characterized in that the means for injecting a test signal comprise a current source or a first switch commanded by a processing unit and a very low-voltage source, wherein a nature of the electrical load is detected depending on a waveform of a return signal obtained by the processing unit;
a resistor electrically connected to the first switch at one node and to a diode at another node; and
a differentiator (DIFF) configured in parallel with the resistor, wherein the DIFF is configured to measure:
current I 1 into the resistor at one node by a positive terminal of the DIFF, and
current I 2 into the diode at another node by a negative terminal of the DIFF.
2. The device according to claim 1 , comprising a second switch commanded by the processing unit, said first and second switches being commanded alternately during operation.
3. The device according to claim 2 , wherein the first switch is driven by a pulse width modulated (PWM) signal, and wherein the second switch is driven by inverting the PWM signal.
4. The device according to claim 1 , wherein the means for identifying the presence and the nature of the electrical load comprise an anti-aliasing filter connected to a processing unit.
5. A controller for managing the supply of electric power to an electrical load for an aircraft, comprising an electric power supply line and a load detection device linked to said power supply line and comprising means for injecting a test signal into the electrical network and means for identifying the presence and the nature of the electrical load connected to the electrical network on the basis of the test signal, characterized in that the means for injecting a test signal comprise a current source or a first switch commanded by a processing unit and a very low-voltage source, and characterized in that a nature of the electrical load is detected depending on a waveform of a return signal obtained by the processing unit;
wherein the controller further comprises:
a resistor electrically connected to the first switch at one node and to a diode at another node; and
a differentiator (DIFF) configured in parallel with the resistor, wherein the DIFF is configured to measure:
current I 1 into the resistor at one node by a positive terminal of the DIFF, and
current I 2 into the diode at another node by a negative terminal of the DIFF.
6. The controller according to claim 5 , wherein the load detection device is connected in parallel across the electric power supply line.
7. The controller according to claim 5 , wherein the power supply line comprises a fuse connected in series across the power supply line, the detection device being connected across the power supply line in parallel with the fuse.
8. A method for detecting an electrical load supplied with power by an electric power supply controller comprising an electric power supply line and a device for detecting an electrical load linked to said power supply line, characterized in that the method includes:
at least one step during which the detection device injects a test signal into the line supplying power to the load, the main power supply of the power supply line being cut, wherein means for injecting the test signal comprise a current source or a first switch commanded by a processing unit and a very low-voltage source; and
at least one step during which the detection device detects a nature of the electrical load depending on a waveform of a return signal obtained by the device for detecting the electrical load,
wherein the device for detecting the electrical load comprises:
a resistor electrically connected to the first switch at one node and to a diode at another node; and
a differentiator (DIFF) configured in parallel with the resistor, wherein the DIFF is configured to measure:
current I 1 into the resistor at one node by a positive terminal of the DIFF, and
current I 2 into the diode at another node by a negative terminal of the DIFF.
9. The method according to claim 8 , wherein the detection device compares a value of the impedance of the load with a predetermined value.