Isolated measurement system with power transmitter disabling

• US 9,184,588 B2
• Filed: 11/06/2012
• Issued: 11/10/2015
• Est. Priority Date: 04/23/2012
• Status: Active Grant

• Current Assignee: Analog Devices, Inc.
• Original Assignee: Analog Devices, Inc.
• Inventors: Mueck, Michael
• Primary Examiner(s): Lee, Thomas
• Assistant Examiner(s): Chan, Danny
• Application Number:
  US13/670,315
• Publication Number:
  US 20130278077A1
• Time in Patent Office: 1,099 Days
• US Class Current: 1/1
• CPC Class Codes: G06F 1/26 Power supply means, e.g. regulation thereof for memories G11C
• CPC Class Codes: H02J 1/02 Arrangements for reducing harmonics or ripples
• CPC Class Codes: H04Q 2209/883 where the sensing device enters an active or inactive mode
• CPC Class Codes: H04Q 9/00 Arrangements in telecontrol or telemetry systems for selectively calling a substation from a main station, in which substation desired apparatus is selected for applying a control signal thereto or for obtaining measured values therefrom

Abstract

A power delivery system is disclosed for an isolated measurement system in which a power transmitter and power receiver are provided at powered and unpowered sides of an isolation barrier, respectively. The power transmitter and power receiver may be coupled by an isolator. The power transmitter may deliver power to the power receiver to power components on the unpowered side of the isolation barrier. The system may include a controller provided in the powered side to generate a clock signal defining timing of a predetermined operation of the measurement system and to generate a disabling signal to the power transmitter controller synchronously with the timing of the predetermined operation.

Claims

1. A system for performing isolated measurement, comprising:

a power transmitter provided on a first side of an isolation barrier,

a power receiver provided on a second side of the isolation barrier,

a first isolator coupling the power transmitter to the power receiver, and

a control system, provided in the first side, to provide a clock signal defining timing of a predetermined input sampling operation of a measurement system in the second side and to generate a disabling signal to the power transmitter synchronously with the timing of the predetermined input sampling operation,

a second isolator for transmission of data between the first side and the second side,

wherein the power transmitter is disabled from transmitting power for the timing of the predetermined input sampling operation based on the disabling signal.

2. The system of claim 1, wherein

the second side to receive the clock signal from the first side and produce an isolated clock signal for the measurement system provided on the second side.

3. The system of claim 2, wherein the measurement system comprises an analog to digital converter.

4. The system of claim 3, wherein the measurement system comprises a sigma delta analog to digital converter.

5. The system of claim 3, wherein the measurement system comprises a multi-bit analog to digital converter.

6. The system of claim 2, wherein the control system and power transmitter are provided in a package separate from a package in which the power receiver and measurement system are provided.

7. The system of claim 2, wherein the control system, power transmitter, power receiver and measurement system are provided in a common package.

8. The system of claim 2, further comprising a monitor provided in the second side to measure at least one of a voltage and current to obtain an indication of power received by the power receiver.

9. The system of claim 1, further comprising a power control system, provided in the first side, to modulate the disabling signal according to power feedback signals received from the second side.

10. The system of claim 9, wherein the disabling signal has an activation period that varies from a minimum duration to a maximum duration according to the power feedback signals.

11. The system of claim 9, wherein the disabling signal has an activation period that toggles between a minimum duration and a maximum duration according to the power feedback signals.

12. The system of claim 1, wherein the predetermined input sampling operation is sampling an input voltage by the measurement system.

13. The system of claim 1, wherein the predetermined input sampling operation is settling of voltages stored on or removed from capacitors within an analog to digital converter of the measurement system.

14. The system of claim 1, wherein the predetermined input sampling operation is comparison operations of a comparator within an analog to digital converter of the measurement system.

15. A method of controlling an isolated measurement system, comprising:

delivering power via a first isolator from the first side of an isolation barrier to a second side of an isolation barrier by an isolator driving signal,

generating, on a first side of the isolation barrier, a clock signal defining timing of a predetermined input sampling operation of a measurement system on a second side of the isolation barrier,

transmitting the clock signal to the second side via a second isolator,

receiving measurement data from the second side, wherein the measurement data is not received via the first isolator, and

disabling the isolator driving signal synchronously with the predetermined input sampling operation.

16. The method of claim 15, wherein the predetermined input sampling operation is a sampling of a voltage at an input of the measurement system.

17. The method of claim 15, wherein the predetermined input sampling operation is a sampling of a voltage by an analog-to-digital converter of the measurement system.

18. The method of claim 17, wherein the isolator driving signal resumes during a conversion operation of the analog-to-digital converter.

19. The method of claim 15, wherein the predetermined input sampling operation is sampling an input voltage by the measurement system.

20. The method of claim 15, wherein the predetermined input sampling operation is settling of voltages stored on or removed from capacitors within an analog to digital converter of the measurement system.

21. The method of claim 15, wherein the predetermined input sampling operation is comparison operations of a comparator within an analog to digital converter of the measurement system.

22. The method of claim 15, further comprising:

measuring at least one of a voltage and current to obtain an indication of power received at the second side based on the power delivery, and

generating a power control signal representing the measured power, and

transmitting data representing the power control signal from the second side to the first side.

23. The method of claim 22, wherein the power control signal is transmitted synchronously with the clock signal.

24. The method of claim 22, wherein the power control signal is multiplexed with measurement data of the measurement system prior to transmission.

25. The method of claim 22, further comprising varying, in response to the power control signals, a duration of times at which the isolator driving signal is disabled.

26. A system, comprising:

a power transmitter provided on a first side of an isolation barrier,

a power receiver provided on a second side of the isolation barrier,

a measurement system provided on the second side of the isolation barrier to generate measurement data,

a power monitor provided on the second side of the isolation barrier to measure power received by the power receiver and to generate power measurement signals;

a first isolator coupling the power transmitter to the power receiver,

a second isolator to carry the power measurement signals from the second side to the first side,

and a power controller to modulate a control signal to the power transmitter, the control signal defining a duty cycle of activation of the power transmitter, wherein the control signal deactivates the power transmitter at times when the measurement system performs input sampling operations.

27. The system of claim 26, further comprising a clock generator in the first side, an output of the clock generator defining timing of the input sampling operations of the measurement system.

28. The system of claim 26, wherein the power measurement signals are merged with the measurement data from the measurement system and transmitted across the second isolator.

29. The system of claim 26, wherein the power controller generates a pulse width modulated control signal to the power transmitter.

30. The system of claim 26, wherein the power controller generates a control signal to the power transmitter whose pulse duration toggles between a first and second duration.

31. A system for controlling isolated measurements, comprising:

a power transmitter provided on a first side of an isolation barrier, having an output coupled to a first isolator, to provide power to a second side of the isolation barrier,

a control system provided on the first side having;

a first output, coupled to a second isolator, for a clock signal defining timing of a predetermined input sampling operation of a measurement system on the second side of the isolation barrier, and

a second output, coupled to the power transmitter, for a disabling signal that disables the power transmitter synchronously with the timing of the predetermined input sampling operation.