Power supply for powering a load, method for powering the load

1 . A power supply for powering a load, the power supply comprising:

an input terminal configured to be connected to an external power supply having a mains voltage,

an output terminal configured to be connected to the load,

a power converter configured to convert a supply power, received from the external power supply, to a load power,

a measurement circuit configured to provide a signal representative of the mains voltage, and

a control unit configured to:

determine a voltage and a current on a load side of the power converter, and

receive the signal from the measurement circuit and to determine the mains voltage based on the signal, and

determine the load power supplied on the load side of the power converter, based on the determined voltage and current on the load side of the power converter, and

determine a loss power representing the power loss from the external power supply to the load side of the power converter, based on a loss model as a function of the determined voltage and current on the load side of the power converter and the determined mains voltage, and

determine the supply power, received from the external power supply, based on the determined load power and the determined loss power.

2 . The power supply according to claim 1 , wherein the power converter comprises an isolation transformer, the isolation transformer having a primary circuit connected to the input terminal and a secondary circuit connected to the output terminal, the secondary circuit being electrically isolated from the primary circuit and magnetically coupled to the primary circuit.

3 . The power supply according to claim 2 , wherein the measurement circuit is configured to measure the voltage and current on the secondary circuit of the isolation transformer.

4 . The power supply according to claim 2 , wherein the measurement circuit is configured to measure the voltage and current on the primary circuit of the isolation transformer.

5 . The power supply according to claim 1 , wherein the measurement circuit is configured to generate the signal representative of the mains voltage on the load side of the power converter.

6 . The power supply according to claim 5 , wherein the signal is based on a conduction period of current flowing through the secondary circuit when the power converter is switched from a first state to a second state.

7 . The power supply according to claim 1 , wherein the measurement circuit is configured to generate the signal representative of the mains voltage on a mains side of the power converter.

8 . The power supply according to claim 1 , wherein the loss model is an empirical loss model.

9 . The power supply according to claim 1 , wherein the external power supply is an AC power supply.

10 . The power supply according to claim 9 , wherein the power supply comprises a rectifier for rectifying the AC power supply.

11 . The power supply according to claim 10 , wherein the power converter comprises an EMI filter arranged downstream of the rectifier.

12 . The power supply according to claim 1 , wherein the power converter comprises a flyback converter.

13 . The power supply according to claim 1 , wherein the power converter comprises a buck or boost converter arranged downstream of the flyback or resonant converter.

14 . The power supply according to claim 1 , wherein the power converter comprises a resonant converter.

15 . The power supply according to claim 14 , wherein the power converter comprises a PFC-boost circuit arranged upstream of the resonant converter.

16 . The power supply according to claim 1 , wherein the measurement circuit is configured to determine an internal current associated with the resonant converter.

17 . The power supply according to claim 1 , wherein the measurement circuit is configured to determine an internal current associated with the PFC-boost circuit.

18 . The power supply according to claim 1 , wherein the external power supply is a DC power supply.

19 . The power supply for powering a load, the power supply comprising:

an input terminal configured to be connected to an external power supply having a mains voltage,

an output terminal configured to be connected to the load,

a power converter configured to convert a supply power, received from the external power supply, to a load power, the power converter having an isolation transformer having a primary circuit connected to the input terminal and a secondary circuit connected to the output terminal, the secondary circuit being electrically isolated from the primary circuit and magnetically coupled to the primary circuit,

a measurement circuit configured to provide a signal representative of an internal current associated with the power converter, and

a control unit configured to:

determine one or more electrical characteristics on the primary circuit of the isolation transformer, and

receive the signal from the measurement circuit,

determine the load power supplied on the primary circuit of the isolation transformer, based on the determined one or more electrical characteristics and the internal current associated with the power converter, and

determine a loss power representing the power loss from the external power supply to a mains side of the power converter, based on a loss model as a function of the determined one or more electrical characteristics and the internal current associated with the power converter, and

determine the supply power, received from the external power supply, based on the determined load power and the determined loss power.

20 . The power supply according to claim 19 , wherein the one or more electrical characteristics comprise a voltage on the primary circuit of the isolation transformer.

21 . The power supply according to claim 19 , wherein the loss model is an empirical loss model.

22 . The power supply according to claim 19 , wherein the external power supply is an AC power supply.

23 . The power supply according to claim 22 , wherein the power supply comprises a rectifier for rectifying the AC power supply.

24 . The power supply according to claim 23 , wherein the power converter comprises an EMI filter arranged downstream of the rectifier.

25 . The power supply according to claim 19 , wherein the power converter comprises a flyback converter.

26 . The power supply according to claim 25 , wherein the power converter comprises a buck or boost converter arranged downstream of the flyback or resonant converter.

27 . The power supply according to claim 19 , wherein the power converter comprises a resonant converter.

28 . The power supply according to claim 27 , wherein the power converter comprises a PFC-boost circuit arranged upstream of the resonant converter.

29 . The power supply according to claim 27 , wherein the measurement circuit is configured to determine an internal current associated with the resonant converter.

30 . The power supply according to claim 28 , wherein the measurement circuit is configured to determine an internal current associated with the PFC-boost circuit.

31 . The power supply according to claim 19 , wherein the external power supply is a DC power supply.

32 . The power supply according to claim 19 , wherein the measurement circuit is configured to provide a further signal representative of the mains frequency or a quality characteristic of the external power supply to the control unit.

33 . The power supply according to claim 32 , wherein the control unit is configured to log and report the further signal.

34 . A method for powering a load, the method comprising the steps of:

connecting an input terminal to an external power supply having a mains voltage,

connecting an output terminal to the load,

converting a supply power, received from the external power supply, by a power converter to a load power,

determining a voltage and a current on a load side of the power converter,

providing a signal representative of the mains voltage,

receiving the signal to determine the mains voltage,

determining the load power supplied on the load side of the power converter, based on the determined voltage and current on the load side of the power converter,

determining a loss power representing the power loss from the external power supply to the load side of the power converter, based on a loss model as a function of the determined voltage and current on the load side of the power converter and the determined mains voltage, and

determining the supply power, received from the external power supply, based on the determined load power and the determined loss power.

35 . The method according to claim 34 , further comprising the steps of:

connecting a primary circuit to the input terminal and

connecting a secondary circuit to the output terminal, the secondary circuit being electrically isolated from the primary circuit and magnetically coupled to the primary circuit.

36 . The method according to claim 35 , wherein the step of determining the voltage and the current on the load side of the power converter comprises determining the voltage and the current on the secondary circuit.

37 . The method according to claim 35 , wherein the step of determining the voltage and the current on the load side of the power converter comprises determining the voltage and the current on the primary circuit.

38 . The method according to claim 36 , wherein the step of providing the signal comprises the measuring of a conduction period of current flowing through the secondary circuit when the power converter is switched from a first state to a second state.

39 . The method according to claim 34 , wherein the step of providing the signal comprises the providing of the signal representative of the mains voltage on the load side of the power converter.

40 . The method according to claim 34 , wherein the step of providing the signal comprises the providing of the signal representative of the mains voltage on a mains side of the power converter.

41 . The method according to claim 34 , further comprising the step of rectifying the external power supply.

42 . Method The method according to claim 34 , further comprising the step of determining an internal current associated with the power converter.

43 . A method for powering a load, the method comprising the steps of:

connecting an input terminal to an external power supply having a mains voltage,

connecting an output terminal to the load,

converting a supply power, received from the external power supply, by a power converter to a load power, the power converter having a primary circuit connected to the input terminal and a secondary circuit connected to the output terminal, the secondary circuit being electrically isolated from the primary circuit and magnetically coupled to the primary circuit,

determining one or more electrical characteristics on the primary circuit,

providing a signal representative of an internal current associated with the power converter,

receiving the signal,

determining the load power supplied on the primary circuit, based on the determined one or more electrical characteristics and the internal current associated with the power converter,

determining a loss power representing the power loss from the external power supply to a mains side of the power converter, based on a loss model as a function of the determined one or more electrical characteristics and the internal current associated with the power converter, and

determining the supply power, received from the external power supply, based on the determined load power and the determined loss power.

44 . The method according to claim 43 , further comprising the step of rectifying the external power supply.

45 . The method according to claim 43 , further comprising the step of determining an internal current associated with the power converter.