Method and circuit for complying with maximum values for output parameters of a power supply unit

Patent metadata

Field	Value
Publication number	US-11070050-B2
Application number	US-201816116167-A
Country	US
Kind code	B2
Filing date	Aug 29, 2018
Priority date	Aug 29, 2017
Publication date	Jul 20, 2021
Grant date	Jul 20, 2021

Abstract

A method and a circuit for complying with specified maximum values for output parameters a power supply unit includes at least a non-floating switch converter, an output voltage control unit, a current limiter and a switch element, wherein actual values of the current and voltage outputs of the power supply unit are measured continuously, where an evaluation unit calculates actual output power values of the power supply unit from the actual measured values of the output current and voltages, and subsequently compares at least the respective actually measured values of the output current and the respective actually calculated output power values with specified maximum values such that if at least one of the specified maximum values is exceeded by an actually measured value of the output current and/or by an actually calculated output power value, a current flow in the power supply unit is then interrupted by the evaluation unit.

First claim

What is claimed is:

1. A method for complying with specified maximum values for output parameters of at least one power supply unit comprising at least a non-floating switch converter, a switch element, an output voltage control unit and an internal current limiter, the method comprising:
measuring actual values of an output current of the at least one power supply unit and actual values of an output voltage of the at least one power supply unit continuously;
calculating, by an evaluation unit, actual output power values of the at least one power supply unit from the actually measured values of the output current and the output voltage;
comparing respective actually measured values of the output current and respective actually calculated output power values with corresponding specified maximum values by the evaluation unit; and
interrupting a current flow of the at least one power supply unit by the evaluation unit if at least one of the specified maximum values is exceeded by an actually measured value of at least one of (i) the output current and (ii) an actually calculated output power value.

2. The method as claimed in claim 1 , wherein actual values of an input current of the at least one power supply unit and actual values of an input voltage of the at least one power supply unit are measured continuously;
wherein respective actual input power values for the at least one power supply unit are calculated by the evaluation unit from the respective actually measured values of input current and input voltage;
wherein a difference between respective actually calculated output power values and respective actually calculated input power values is determined by the evaluation unit and compared with a specified maximum permitted power difference; and
wherein the current flow of the at least one power supply unit is interrupted by the evaluation unit if the maximum permitted power difference is exceeded.

3. The method as claimed in claim 1 , wherein a trigger signal is sent at regular intervals from the evaluation unit to a monitoring unit; and wherein if the trigger signal is absent, a reset signal is sent from the monitoring unit to the evaluation unit and the current flow of the at least one power supply unit is interrupted.

4. The method as claimed in claim 2 , wherein a trigger signal is sent at regular intervals from the evaluation unit to a monitoring unit; and wherein if the trigger signal is absent, a reset signal is sent from the monitoring unit to the evaluation unit and the current flow of the at least one power supply unit is interrupted.

5. The method as claimed in claim 1 , wherein any operation of the switch converter of the at least one power supply unit outside of a voltage-controlled range and a current-controlled range is detected by the evaluation unit based on the actually measured values of the output current and the output voltage; and wherein the current flow of the at least one power supply unit is interrupted by the evaluation unit.

6. The method as claimed in claim 2 , wherein any operation of the switch converter of the at least one power supply unit outside of a voltage-controlled range and a current-controlled range is detected by the evaluation unit based on the actually measured values of the output current and the output voltage; and wherein the current flow of the at least one power supply unit is interrupted by the evaluation unit.

7. The method as claimed in claim 3 , wherein any operation of the switch converter of the at least one power supply unit outside of a voltage-controlled range and a current-controlled range is detected by the evaluation unit based on the actually measured values of the output current and the output voltage; and wherein the current flow of the at least one power supply unit is interrupted by the evaluation unit.

8. The method as claimed in claim 1 , further comprising:
measuring a supply voltage of the evaluation unit and comparing said measured supply voltage with a specified permitted value range for the supply voltage by the evaluation unit, and
interrupting the current flow of the at least one power supply unit by the evaluation unit if the measured supply voltage deviates from the specified permitted value range.

9. The method as claimed in claim 1 , wherein the switch element of the at least one power supply unit is activatable by the evaluation unit to interrupt the current flow of the at least one power supply unit.

10. The method as claimed in claim 1 , wherein one of (i) an activatable switch element which is additionally mounted on an input side of the at least one power supply unit is utilized to interrupt the current flow and (ii) a switch converter which is arranged upstream or downstream of the at least one power supply unit is utilized to interrupt the current flow.

11. The method as claimed in claim 1 , wherein the output parameters the at least one power supply unit comprise at least one of (i) an output current and (ii) an output power.

12. A circuit for complying with specified maximum values for output parameters of at least one power supply unit, the circuit comprising:
at least one power supply unit including at least a non-floating switch converter, a switch element, an output voltage control unit, and an internal current limiter;
measuring units for measuring actual values of an output current and an output voltage of the at least one power supply unit; and
an evaluation unit which is configured to calculate actual output power values from actually measured values of the output current and the output voltage of the at least one power supply unit, configured to compare respective actually measured values of the output current and respective actually calculated output power values with specified maximum values, and configured to interrupt a current flow of the at least one power supply unit if at least one specified maximum value is exceeded.

13. The circuit as claimed in claim 12 , further comprising:
additional measuring units for measuring actual values of an input current and an input voltage of the at least one power supply unit;
wherein the evaluation unit is further configured to calculate actual input power values from the actually measured values of the input voltage and the input current, further configured to determine a difference between respective actually calculated output power values and respective actually calculated input power values, further configured to compare said difference with a maximum permitted power difference, and further configured to interrupt the current flow of the at least one power supply unit if the maximum permitted power difference is exceeded.

14. The circuit as claimed in claim 12 , further comprising:
a monitoring unit for receiving a trigger signal from the evaluation unit and sending a reset signal if the trigger signal is absent.

15. The circuit as claimed in claim 13 , further comprising:
a monitoring unit for receiving a trigger signal from the evaluation unit and sending a reset signal if the trigger signal is absent.

16. The circuit as claimed in claim 12 , wherein the switch element of the at least one power supply unit is activatable by the evaluation unit to interrupt the current flow of the at least one power supply unit.

17. The circuit as claimed in claim 12 , wherein one of (i) an additional switch element is mounted on an input side of the at least one power supply unit to interrupt the current flow of the at least one power supply unit and (ii) a switch converter is arranged upstream or downstream of the at least one power supp

Assignees

• Siemens Ag

Inventors

• Benesch Karl
• Paul Wolfgang

Classifications

• H02M7/1555

  with control circuit · CPC title

• H02H7/1227

  responsive to abnormalities in the output circuit, e.g. short circuit · CPC title

• H02H3/42

  responsive to product of voltage and current · CPC title

• H02M3/156 Primary

  with automatic control of output voltage or current, e.g. switching regulators · CPC title

• H02H3/087

  for DC applications · CPC title