Electrical supply system
An electrical supply system including a voltage converter including having an input electrically coupled to a supply for receiving a supply signal and an output for supplying an output signal having a output voltage different to a supply voltage of the supply signal. The system includes a diode including a diode input electrically coupled to the voltage converter output, a bus electrically coupled to a diode output and at least one of a load and a store, a voltage sensor for detecting the output voltage, a current sensor for detecting a diode input current and an electronic processing device coupled to the sensors for monitoring the diode input current and the output voltage and detecting a fault in the electrical supply system based on at least the diode input current and output voltage.
1. An electrical isolator for isolating a power supply of an electrical supply system, the isolator including a voltage converter having:
a) a voltage converter input electrically coupled to a supply for receiving a supply signal; and
b) a voltage converter output for supplying an output signal, the output signal having a output voltage different to a supply voltage of the supply signal;
c) a transformer;
d) a switching circuit coupled to the voltage converter input and the transformer; and
e) a controller configured to:
i) detect an electrical fault in the electrical supply system; and,
ii) control the switching circuit to thereby selectively apply the supply signal to a transformer input to thereby at least one of:
(1) generate the output signal if no fault is detected; and,
(2) electrically isolate the voltage converter input from the voltage converter output if a fault is detected.
2. The electrical isolator according to claim 1 , wherein the switching circuit includes a plurality of switches.
3. The electrical isolator according to claim 2 , wherein the switches include transistors.
4. The electrical isolator according to claim 2 , wherein the controller causes the switches to toggle to thereby periodically reverse the polarity of the supply signal applied to the transformer input.
5. The electrical isolator according to claim 4 , wherein the frequency of switching is used to control the output voltage of the voltage converter.
6. The electrical isolator according to claim 5 , wherein the output voltage of the voltage converter is controlled in order to regulate voltage changes in the system caused by one or more of the supply and a load or battery electrically coupled to the supply.
7. The electrical isolator according to claim 6 , wherein the supply is a photovoltaic (PV) cell and the output voltage of the voltage converter is controlled in order to achieve maximum power point tracking (MPPT).
8. The electrical isolator according to claim 2 , wherein the switches are metal oxide semiconductor field effect transistors.
9. The electrical isolator according to claim 2 , wherein the voltage converter includes a rectifier for coupling the transformer to the voltage converter output.
10. The electrical isolator according claim 1 , wherein the voltage converter includes galvanic isolation in which functional sections of the voltage converter are electrically isolated.
11. The electrical isolator according to claim 1 , wherein the controller at least in part detects a fault in the electrical supply system using a diode input current of a diode electrically coupled to the voltage converter output.