Back to results
US 9,461,320 B2Granted
Structure and method for fuel cell system where multiple fuel cells and power electronics feed loads in parallel allowing for integrated electrochemical impedance spectroscopy (EIS)
AssigneeBloom Energy Corporation
InventorsArne Ballantine, Ranganathan Gurunathan, Prasad Pmsvvsv, Anilkumar Vishnuvarjula
Life of this patent
Estimating the term…
Abstract
Systems, methods, and devices of the various embodiments enable electrochemical impedance spectroscopy (“EIS”) to be performed on electrochemical devices, such as fuel cell stack segments, by power electronics connecting the electrochemical devices in parallel to a common load and/or bus. In an embodiment, the power electronics may compensate for any ripple generated during EIS such that no ripple is realized at the common load and/or bus.
Claims32
A system, comprising:
- a direct current (“DC”) bus;
- a first electrochemical device electrically connected via a first input connection to a first DC converter, wherein the first DC converter is connected via a first output connection to the DC bus;
- at least one second electrochemical device electrically connected via at least one second input connection to at least one second DC converter, wherein the at least one second DC converter is connected via the at least one second output connection to the DC bus and wherein the first output connection and the at least one second output connection connect the first DC converter and the at least one second DC converter to the DC bus in parallel;
- and
- a processor connected to the first DC converter and the at least one second DC converter, wherein the processor is configured with processor-executable instructions to perform operations comprising:
- selecting a test waveform to inject onto the first input connection from the first DC converter to the first electrochemical device;
- determining a first resulting ripple on the first output connection that will be generated in response to injecting the test waveform onto the first input connection;
- determining at least one offset waveform to inject onto the at least one second input connection from the at least one second DC converter to the at least one second electrochemical device such that one or more second ripples which will be provided to the at least one second output connection cancel the first resulting ripple;
- controlling the first DC converter to inject the test waveform onto the first input connection;
- and
- controlling the at least one second DC converter to inject the at least one offset waveform onto the at least one second input connection.
8 more elements
A method, comprising:
- selecting a test waveform to inject onto a first input connection from a first DC converter to a first electrochemical device;
- determining a first resulting ripple on a first output connection of the first DC converter that will be generated in response to injecting the test waveform onto the first input connection;
- determining at least one offset waveform to inject onto at least one second input connection from at least one second DC converter to at least one second electrochemical device such that one or more second ripples which will be provided to at least one second output connection of the at least one second DC converter cancel the first resulting ripple;
- injecting the test waveform onto the first input connection;
- and
- injecting the at least one offset waveform onto the at least one second input connection,
- wherein the first output connection and at least one second output connection connect the first DC converter and the at least one second DC converter to a DC bus in parallel.
4 more elements
A system, comprising:
- a direct current (“DC”) bus;
- a first fuel cell segment electrically connected via a first input connection to a first DC converter, wherein the first DC converter is connected via a first output connection to the DC bus;
- at least one second device connected via at least one second output connection to the DC bus;
- and
- a processor connected to the first DC converter and the at least one second device, wherein the processor is configured with processor-executable instructions to perform operations comprising:
- injecting an electrochemical impedance spectroscopy test waveform into the first fuel cell segment to generate a first resulting ripple to the DC bus;
- and
- injecting at least one second offset ripple to the DC bus from the at least one second device, wherein the at least one second offset ripple at least partially offsets the first resulting ripple on the DC bus.
5 more elements
A method of operating a fuel cell system, comprising:
- injecting an electrochemical impedance spectroscopy test waveform into a first fuel cell segment to generate a first resulting ripple to an output bus of the fuel cell system;
- and
- injecting at least one second offset ripple to the output bus,
- wherein the at least one second offset ripple at least partially offsets the first resulting ripple on the output bus.
1 more element
Dependencies are inferred from the claim text.