ELECTRICALLY ENHANCED COMBUSTION CONTROL SYSTEM WITH MULTIPLE POWER SOURCES AND METHOD OF OPERATION

Abstract

A combustion system is provided that includes a fuel nozzle configured to support a combustion reaction, and an electrode positioned to apply an electrical charge to the combustion reaction. A power converter is positioned to receive heat produced by the combustion reaction and to convert a portion of the received heat to electrical energy. A combustion system controller is configured to provide the electrical charge to the electrode, using energy drawn either from the power converter or from a power storage element, depending on an amount of power being produced by the power converter and on a state-of-charge of the power storage element. The controller is further configured to use surplus energy generated by the power converter to recharge the power storage element.

Description

CROSS REFERENCE TO RELATED APPLICATION

The present application claims priority benefit from U.S. Provisional Patent Application No. 61/822,538, entitled “ELECTRICALLY ENHANCED COMBUSTION CONTROL SYSTEM WITH MULTIPLE POWER SOURCES AND METHOD OF OPERATION”, filed May 13, 2013; which, to the extent not inconsistent with the disclosure herein, is incorporated by reference.

SUMMARY

According to an embodiment, a combustion system is provided that includes a fuel nozzle configured to support a combustion reaction, and an electrode positioned to apply an electrical charge to the combustion reaction. A power converter is positioned to receive heat produced by the combustion reaction and to convert a portion of the received heat to electrical energy. A combustion system controller is configured to provide the electrical charge to the electrode, using energy drawn either from the power converter or from a power storage element, depending on an amount of power being produced by the power converter and on a state-of-charge of the power storage element. The controller is further configured to use surplus energy generated by the power converter to recharge the power storage element.

According to an embodiment, the combustion system controller is configured to draw power from an external power source if the power converter is not producing sufficient power to provide the electrical charge to the electrode and the power storage element is depleted.

According to an embodiment, the combustion system controller is configured to transmit power to the external power source if the power converter is producing more power than is necessary to provide the electrical charge to the electrode and the power storage element is fully charged.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a diagrammatic representation of a combustion system, according to an embodiment.

FIG. 2 is a view of a portion of the combustion system of FIG. 1, showing in more detail, in particular, a power converter of the combustion system of FIG. 1, according to an embodiment.

FIG. 3 is a diagrammatic representation of a combustion system, according to another embodiment.

FIG. 4 is a flow chart illustrating elements of a method of operation of a combustion system, according to an embodiment.

FIG. 5 is a flow chart illustrating elements of a method of operation of a combustion system, according to another embodiment.

DETAILED DESCRIPTION

In the following detailed description, reference is made to the accompanying drawings, which form a part hereof. In the drawings, similar symbols typically identify similar components, unless context dictates otherwise. Other embodiments may be used and/or other changes may be made without departing from the spirit or scope of the disclosure.

Electrically enhanced combustion systems (EEC), are combustion systems that include a structure configured to apply electrical energy to a combustion reaction. Application of electrical energy to a combustion reaction is described in a number of recent patent applications, including the following, all of which are incorporated herein by reference, in their entireties: “SYSTEM AND APPARATUS FOR APPLYING AN ELECTRIC FIELD TO A COMBUSTION VOLUME”, U.S. Non-Provisional patent application Ser. No. 12/753,047, filed Apr. 1, 2010; “METHOD AND APPARATUS FOR ELECTRICAL CONTROL OF HEAT TRANSFER”, U.S. Non-Provisional patent application Ser. No. 13/006,344, filed Jan. 13, 2011; and “MULTIPLE FUEL COMBUSTION SYSTEM AND METHOD”, U.S. Non-Provisional patent application Ser. No. 13/731,109, filed Dec. 30, 2012.

As explained in detail in the patent applications referenced above, application of electrical energy, such as a charge or electrical potential to a combustion reaction typically involves generation of a high-voltage signal that can reach values of greater than 100 kV, and applying that signal to the combustion reaction or supporting fuel jet via an electrode positioned adjacent to, or in contact with the combustion reaction and/or fuel jet. The signal can be a constant value signal, or can vary over time, can include a wide range of waveforms, and can alternate polarity. Depending on the purpose and configuration of a particular system, application of a charge to the combustion reaction can produce a number of significant benefits, again, as outlined in the referenced applications.

The inventor has recognized a number of concerns that might be associated with combustion systems that include the application of a charge to a combustion reaction. For example, there is a widely perceived danger of injury anytime a high-voltage potential is present, even when as in the present case, the very low current involved reduces the actual danger. Nevertheless, it is desirable to take steps to ensure that, in case of a malfunction or fault in the electrical circuitry, a high-voltage charge cannot be applied to portions of the system that are normally operated at relatively low voltages, or that are electrically neutral. Not only does this help protect users from painful and potentially harmful shocks, but it also helps protect low-voltage circuits and equipment from damage resulting from exposure to high-voltage potentials.

The inventor has also recognized that in some applications, a source of electrical power may be unavailable, or require significant expense to access.

For example, in a petroleum refinery, thermal energy is used in many parts of the processes employed to separate specific compounds from crude oil, and to generate reactions for forming other compounds. Given the size of many refineries, many of the burner systems employed may be in locations that are far removed from available sources of electricity. Additionally, routing power to those locations may be difficult or impossible to accomplish without running power lines through areas where the presence of such power lines is prohibited because of the danger posed by the potential for generation of electric sparks.

FIG. 1 is a simplified diagrammatic representation of a combustion system 100, according to an embodiment. The system 100 includes a burner assembly 110, a power converter 120, and a system controller 130.

The burner assembly 110 includes a burner nozzle 112 configured to emit a fuel jet 114 configured to support a combustion reaction 116. An electrode 118 is positioned and configured to apply a charge to the combustion reaction 116. The power converter 120 is configured to receive thermal energy from the combustion reaction 116, and to convert a portion of the received thermal energy into electrical energy. An output power level sensor that is incorporated into or coupled to the power converter 120 provides a signal corresponding to the power output of the device. Elements of the power converter 120, according to an embodiment, will be described below in more detail with reference to FIG. 2.

The system controller 130 includes a combustion control module 132, a power storage module 134, a controller module 136, and a switch module 138. The combustion control module 132 includes an input terminal at which it receives a low-voltage supply of power, and an output terminal coupled to the electrode 118 of the burner assembly 110. The combustion control module 132 is configured to convert the low-voltage power at the input terminal to a high-voltage signal to be applied to the combustion reaction 116. There are a number of known methods for producing a high-voltage signal, including, for example, charge pump, boost converter, and voltage multiplier, any of which can be employed, according to the particular application. The power storage module 134 is configured to receive and store electrical energy for later use. The power storage module 134 preferably includes at least one storage battery, and may, according to various embodiments, include a plurality of storage batteries arranged in series or parallel, or configured to be independently charged and discharged. Alternatively, the power storage module 134 may employ other devices for storing electrical power, such as, for example, high-efficiency capacitors. A power storage level sensor that is incorporated into or coupled to the power storage module 134 provides a signal corresponding to the amount of available stored energy—often referred to as the state-of-charge (SOC) of the device. The switch module 138 is coupled to the power converter 120, the combustion control module 132, and the power storage module 134 via power transmission line 144. Additionally, according to an embodiment, the switch module 138 includes an input terminal coupled to an external power supply 150, such as a local or municipal power grid, etc.

In the embodiment of FIG. 1, the switch module 138 includes first and second switches 140, 142. The first switch 140 is an SPTT (single-pole triple throw) switch having a common node coupled to the power converter 120, a first position switch node coupled to the external power supply 150, a second position switch node coupled to the power storage module 134, and a center off position. The second switch 142 is an SPTT switch having a common node coupled to the combustion control module 132, a first position switch node coupled to the power converter 120, a second position switch node coupled to the external power supply 150 and a third position switch node coupled to the power storage module 134.

The first switch 140 controls transmission of power from the power converter 120, to the external power supply 150 (in the first position), the power storage module 134 (in the second position), or neither (in the center off position). The second switch 142 controls the source from which power for operation of the combustion control module 132 is drawn. While the second switch 142 is in the first position, the combustion control module 132 is powered by the power converter 120; while in the second position, by the external power supply 150; and in the third position, by the power storage module 134.

The controller module 136 is configured to receive data signals from the output power level sensor of the power converter 120 and the power storage level sensor of the power storage module 134 via data input lines 146, and to provide control signals to the switch module 138 via control lines 148. The controller module 136 is configured to control distribution of power from the power converter 120, determine the source of power for the combustion control module 132, and regulate the charge condition of the power storage module 134. The control module 136 can be implemented in any appropriate form, according to the intended use and operation of the particular application. Examples of various forms that may be employed to control monitoring and switching include hardware circuits, with logic gates or feedback circuits, etc.; processors configured to execute software-based instructions; and circuits employing combinations of hardware, software, firmware, etc. In operation, the controller module 136 compares the power output of the power converter 120 with first and second output thresholds. The first output threshold corresponds to a minimum level of power necessary to power the combustion control module 132, and the second output threshold corresponds to a surplus threshold of power. The controller module 136 is also configured to compare the SOC of the power storage module 134 with first and second storage thresholds. The first storage threshold corresponds to a minimum SOC at which the power storage module 134 is sufficiently charged to reliably power the combustion control module 132, and the second storage threshold corresponds to an SOC at which the power storage module is nominally fully charged. While the power output of the power converter 120 is below the first output threshold—such as when the burner assembly 110 has been recently ignited and has not yet reached operating temperature—the output power is not reliably sufficient to power the combustion control module 132. Accordingly, the controller module 136 controls the first switch 140 to move to its off position, and, if the SOC of the power storage module 134 is above the first storage threshold, the second switch 142 to move to its third position. In this configuration, the combustion control module 132 is powered by the power storage module 134. If the SOC is below the first storage threshold, the controller module 136 controls the second switch 142 to move to its second position, in which case the combustion control module 132 is powered by the external power supply 150.

While the power output of the power converter 120 is above the first output threshold but below the second threshold, the output power is sufficient to power the combustion control module 132, but may not produce power beyond that required by the combustion control module. In this condition, the controller module 136 controls the first switch 140 to move to or remain in its off position and the second switch 142 to move to its first position. In this configuration, the combustion control module 132 is powered by the power converter 120.

Finally, while the power output of the power converter 120 is above second threshold, the output of the power converter 120 is more than sufficient to power the combustion control module 132, so a portion of that power can be drawn off as surplus power. Accordingly, the controller module 136 controls the second switch 142 to move to or remain in its first position, in which case the combustion control module 132 is powered by the power converter 120. Additionally, if the SOC of the power storage module 134 is below the second storage threshold, the controller module 136 controls the first switch 142 to move to its third position, so that a portion of the power from the power converter 120 is sent to charge the power storage module 134. On the other hand, if the SOC of the power storage module 134 is above the second storage threshold (indicating that the storage module is fully charged), the controller module 136 controls the first switch 142 to move to its third position, so that a portion of the power from the power converter 120 is sent to the external power supply 150.

Power sent to the external power supply 150 may be used in a number of different ways, depending, in part, on the particular power configuration, and on the application. For example, if the combustion system 100 is a subsystem of an HVAC system, and the external power supply 150 is a municipal power supply, power from the power converter 120 may be used to offset a portion of the power drawn from the external power supply 150 by other subsystems, thereby reducing the power costs incurred by the overall system. If, in another example, the combustion system 100 is a subsystem of a refinery, and there is no local access to a municipal power grid, the external power supply 150 can include storage batteries used to power other local systems such as sensor suites, computers, wireless transmitters, etc. In such a case, power from the power converter 120 may be used to charge those external storage batteries.

Of course, in some cases, there will be no external power supply 150. For example, according to an embodiment, the combustion system 100 is a subsystem of an isolated system that has no access to an external power grid, and for which the power storage module 134 is a unified energy source, configured to provide power for all subsystems. In such an embodiment, the power converter 120 and the power storage module 134 are configured to have the capacity to meet the increased power generation and storage requirements. According to another embodiment, it is simply more economical to draw the minimal energy necessary to power the combustion control module 132 from the combustion reaction 116 than to provide the necessary connections and draw power from the local grid.

According to an embodiment, where no external power supply 150 is available or required, the first switch 140 is a single pole, double throw (SPDT) switch that is movable between the off position and the second position switch node coupled to the power storage module 134. According to another embodiment, the power storage module includes first and second electric batteries, each of which is capable of powering the combustion control module 132, and which are separately monitored by the control module 136. Additionally, the switch module 138 is configured to separately couple the first and second batteries to the power converter 120 for recharging, as controlled by the control module 136. U.S. Provisional patent application Ser. No. 61/806,357, filed Mar. 28, 2013, entitled “BATTERY-POWERED HIGH-VOLTAGE CONVERTER CIRCUIT WITH ELECTRICAL ISOLATION AND MECHANISM FOR CHARGING THE BATTERY”, teaches a system that includes first and second batteries in an arrangement similar to that described here, and which is incorporated herein in its entirety.

Many elements that are known or understood in the art but are not necessary for an understanding of the principles of the invention are omitted from the drawings and description to avoid unnecessary complexity and reduce the likelihood of confusion. Such omitted elements may include, for example, voltage regulators rectifiers, logic control of applied charge, etc.

FIG. 2 is a view of a portion of the combustion system of FIG. 1, showing in more detail, in particular, the power converter 120 of FIG. 1, according to an embodiment. The power converter 120 is shown coupled to a wall 200 of an enclosure in which the combustion reaction 116 occurs, and includes a block 202 of thermally conductive material, such as, e.g., copper or aluminum, coupled to the wall 200 of the enclosure. A thermoelectric panel 204 is positioned with a first face in thermal contact with the side of the block 202 opposite the wall 200, and a heat sink 206 coupled to a second face. The block 202 acts to provide a rigid, planar surface to which the thermoelectric panel 204 can be coupled, while the heat sink 206 dissipates heat from the thermoelectric panel 204 in order to cool the second face. Electricity generated by the thermoelectric panel 204 is transmitted to the system controller 130 via power transmission line 144. A voltage level sensor 208 is configured to detect a voltage level at the output of the thermoelectric panel 204 and to transmit this information to the system controller 130 via data transmission line 146.

The voltage level sensor 208 can include, for example, a comparator configured to compare a voltage level at an output of the power converter 120 with a reference voltage, and to provide a binary signal indicating whether the voltage at the output is above or below the reference voltage.

Thermoelectric devices are well known, and are commonly used to perform various functions, according to specific thermoelectric principles. For example, the Peltier effect refers to a phenomenon that occurs when an electrical potential is applied across a junction of two different conductive materials, in which heat is absorbed at one part of the circuit and released at another. This effect is often employed to cool microprocessors within a computer cabinet, by affixing a thermoelectric panel similar to the thermoelectric panel 204 of FIG. 2 to the outer surface of a microprocessor, and coupling a heat sink 206 to the opposite side of the panel, also as shown in FIG. 2. When a potential of the correct polarity is applied to the thermoelectric panel 204, it draws heat from the side in contact with the microprocessor, and releases the heat on the side with the heat sink 206, which in turn carries the heat out to radiator fins where it can be dissipated by convection. According to another thermoelectric principle, if separate junctions of the circuit are placed at different temperatures, an electric current is generated, according to the Seebeck effect. The greater the temperature differential between the junctions, the stronger the electrical current.

In the present embodiment, the thermoelectric panel 204 is positioned on the wall 200 of the enclosure opposite the combustion reaction 116. The thermoelectric panel 204 is operated as a Seebeck device, to generate electricity to power the combustion control module 132 using a very small portion of the heat produced by the combustion reaction 116. Because Seebeck operation relies on a temperature differential, the heat sink 206 is configured to efficiently dissipate heat, so that the second face of the thermoelectric panel 204 is cooler than the first face, in thermal contact with the wall 200 via the block 202. Cooling of the heat sink 206 is generally greatly enhanced by positioning the power converter 120 in a location where cooler air can circulate and move across the radiator fins of the heat sink 206.

The power converter 120 of FIG. 2 is provided as one example a device that can be used to convert thermal energy to electrical energy to power the combustion controller 132. However, any type of converter that is capable of producing sufficient power without interfering with the primary function of the combustion reaction 116 can be used.

FIG. 3 is a simplified diagram showing a combustion system 300 according to another embodiment. The combustion system 300 differs from the combustion system 100 of FIG. 1 primarily in the structure and operation of the switch module 302, which will be described below. Because the remaining elements are substantially similar to corresponding elements described with reference to FIG. 1, they will not be described in detail here.

The switch module 302 includes a first switch 304 configured to control a source of power for the combustion controller 132, and a second switch 306 configured to control a source of power for charging the power storage module 134. The first switch 304 is a SPDT-type switch with a common node electrically coupled to the input terminal of the combustion controller 132, a first position switch node electrically coupled to the power converter 120, and a second position switch node electrically coupled to the power storage module 134. The second switch 306 is a SPTT-type switch with a common node electrically coupled to the power storage module 134, a first position switch node electrically coupled to the external power supply 150, a second position switch node electrically coupled to the power converter 120, and an off position. The first and second switches 304, 306 are configured so that while the second switch is in its first position, the first switch cannot move to its second position.

The switch module 302 is functionally very similar to the switch module 138 of FIG. 1, in that it is controlled by the control module 136 to select the source of power for the combustion controller 132 on the basis of the output level of the power converter 120 and the SOC of the power storage module 134. However, one significant difference is that the switch module 302 effectively isolates the combustion controller 132 from any direct electrical connection with the external power supply 150. Thus, even in the event of a malfunction, the danger of high voltage being transmitted from the combustion controller 132 to another subsystem is significantly reduced.

See U.S. patent application Ser. No. 61/806,357, referenced above, for a more detailed disclosure related to high-voltage isolation.

In the embodiments of FIGS. 1 and 3, the respective switch modules are each shown as including a pair of mechanical switches 140, 142, and 304, 306. These examples are provided to illustrate some of the many appropriate switching arrangements that can be used to perform the disclosed functions. However, it is well understood in the art that many different combinations of switches can be arranged in configurations that are functionally identical. Furthermore, other types of switches are well known in the art, in addition to mechanical switches, including semiconductor-based switches and optical switches, etc. Accordingly, the claims are not limited by the types or configurations of switches disclosed herein.

FIG. 4 is a flow chart illustrating elements of a method 400 for operating a combustion system, according to an embodiment. For the purposes of the present disclosure, the method 400 will be described with reference to the combustion system of FIG. 1. The first step following the start of the process at step 402 is the initiation of the combustion reaction at step 404. At step 406, the output of the power converter is compared to a first power threshold value. If the output does not exceed the first power threshold (NO path), the combustion controller is powered by energy from the power storage module (step 408), and the process returns to step 406 to repeat the comparison. Typically, when the burner assembly is first ignited, the power converter will not immediately generate much power as the system begins to heat up. Thus, the process cycles through steps 406 and 408 until, as the heat received by the power converter increases, the output rises above the first power threshold.

If the comparison at step 406 shows that the output of the power converter exceeds the first power threshold, the process proceeds to step 410, in which the control module controls the switch module to decouple the power storage module from the combustion control module, and in its place, couple the power converter to the combustion control module. The process then moves to step 412, in which the output of the power converter is compared to a higher, second power threshold value. If the output does not exceed the second power threshold, the process returns to the first comparison step at 406, and cycles through steps 406-412 until the output rises above the second power threshold (or drops below the first threshold). Of course, once the switch module has been moved to a particular switch configuration, such as in the first iteration of step 410, it is not necessary to change the configuration when that same step is repeated during a repeating cycle of steps.

If the output of the power converter exceeds the second power threshold at step 412, the process proceeds to step 414, in which the state-of-charge (SOC), i.e., the available stored energy in the power storage module is compared to a storage threshold to determine whether the power storage module is fully charged. If the available stored energy exceeds the storage threshold, the process again returns to step 406, and cycles through steps 406-414 until some condition changes.

Typically, immediately following a start up of the combustion system, the power storage module will have been drawn down, somewhat, inasmuch as power for operating the combustion control module was drawn therefrom while the system initially warmed. If the available stored energy does not exceed the storage threshold, the process proceeds to step 416, in which the control module controls the switch module to couple the power converter to the power storage module for charging—without decoupling the power converter from the combustion control module. In this configuration, the power converter provides power to operate the combustion control module while simultaneously charging the power storage module.

From step 416, the process returns to the first comparison step at 406 and cycles through steps 406-416 until the power storage module is fully charged. When the power storage module is charged to the point that the available stored energy exceeds the storage threshold at step 414, the control module controls the switch module to decouple the power converter from the power storage module, and the process again returns to step 406 and repeatedly cycles through steps 406-414.

FIG. 5 is a flow chart illustrating elements of a method of operation 500 according to another embodiment. The method 500 is similar in most respects to the method 400 of FIG. 4, except that it is directed to operation of a combustion system that includes a connection to an external power supply, such as, for example, the systems of FIGS. 1 and 3. Only the process steps that are new, relative to the steps described with reference to FIG. 4, will be described in detail. Those that are substantially similar to the steps of FIG. 4, and bear the same reference numbers, will not be described again.

In the process 500, if the comparison at step 406 shows that the output of the power converter does not exceed the first power threshold, the process proceeds to step 507, in which the available stored energy in the power storage module is compared to a first storage threshold. The first storage threshold corresponds to a minimum level of stored energy that is considered to be sufficient to reliably power the combustion control module. If the available stored energy exceeds the first storage threshold, the process proceeds to step 408. If not, the process proceeds to step 509, in which the control module controls the switch module to couple the external power supply with the combustion control module. The process then returns to step 406, and cycles through steps 406-509 until some condition changes.

At step 414, the available stored energy in the power storage module is compared to a second storage threshold. The second storage threshold corresponds to the storage threshold described with reference to step 414 of FIG. 4, and corresponds to a fully charged condition of the power storage module. If the available stored energy does not exceed the second storage threshold, the process proceeds to step 416, as previously described. If the available stored energy does exceed the second storage threshold, the process proceeds to step 517, the control module controls the switch module to decouple the power storage module from the power storage module and to couple the power converter to the external power supply. Surplus power is thus transmitted from the power converter to the external power supply, where it may be used to charge external power storage units, to offset power draw from a municipal grid, etc.

Various embodiments are described in modular form, i.e., as including a number of modules, each having a specific function, such as, a control module, a switch module, etc. This is done in order to provide a clear and simple description of the disclosed embodiments. However, according to various embodiments, the functions of two or more modules can be performed by a single structure, the functions of a module can be distributed among a number of modules, or some or all of the modules can be integrated so as to be inseparably combined. Furthermore, it is not essential that all the disclosed components of a system be collected together in a single enclosure or unit. Instead, elements may be located some distance apart. Claims that recite a number of modules configured to perform specific functions are not limited to structures in which corresponding modules can be separately identified. Instead, such claims read also on devices that are configured to perform the functions of each of the recited modules, without regard for the physical arrangement of the devices or whether the devices include individual modules corresponding to the recited modules.

Ordinal numbers, e.g., first, second, third, etc., are used in the claims according to conventional claim practice, i.e., for the purpose of clearly distinguishing between claimed elements or features thereof. The use of such numbers does not suggest any other relationship, e.g., order of operation or relative position of such elements. Furthermore, ordinal numbers used in the claims have no specific correspondence to those used in the specification to refer to elements of disclosed embodiments on which those claims read, nor to numbers used in unrelated claims to designate similar elements or features.

The abstract of the present disclosure is provided as a brief outline of some of the principles of the invention according to one embodiment, and is not intended as a complete or definitive description of any embodiment thereof, nor should it be relied upon to define terms used in the specification or claims. The abstract does not limit the scope of the claims.

While various aspects and embodiments have been disclosed herein, other aspects and embodiments are contemplated. The various aspects and embodiments disclosed herein are for purposes of illustration and are not intended to be limiting, with the true scope and spirit being indicated by the following claims.

Claims

1. A system, comprising:

a switch module;

a combustion control module having a power input terminal operatively coupled to the switch module and configured to control an electrical charge applied to a combustion reaction of a burner assembly;

a power converter having a power output terminal operatively coupled to the switch module and configured to convert thermal energy to electrical energy;

a power storage module operatively coupled to the switch module and configured to store electrical energy; and

a switch control module operatively coupled to the switch module and configured to:

monitor a power output level of the power converter,

monitor a state-of-charge level of the power storage module,

control the switch module to electrically couple the power output terminal of the power converter with the power input terminal of the combustion control module while the power output level of the power converter is above a first power threshold,

control the switch module to electrically couple the power storage module to the power input terminal of the combustion control module while the power output level of the power converter is below the first power threshold, and control the switch module to electrically couple the power output terminal of the power converter to the power input terminal of the combustion control module and to the power storage module while the power output level of the power converter is above a second power threshold, higher than the first power threshold, and the state-of-charge level of the power storage module is below a first storage threshold.

2. The system of claim 1, wherein the first power threshold corresponds to a minimum power level for powering the combustion control module.

3. The system of claim 1, wherein:

the switch module includes an input terminal configured to be coupled to an external power source; and

the switch control module is configured to control the switch module to electrically couple the input terminal of the switch module to the power input terminal of the combustion control module while the power output level of the power converter is below the first power threshold and the state-of-charge level of the power storage module is below a second storage threshold.

4. The system of claim 3, wherein the second storage threshold is lower than the first storage threshold.

5. The system of claim 3, wherein the switch control module is configured to control the switch module to electrically couple the power output terminal of the power converter to the power input terminal of the combustion control module and to the input terminal of the switch module while the power output level of the power converter is above the second power threshold and the state-of-charge level of the power storage module is above the first storage threshold.

6. The system of claim 5, wherein the first storage threshold corresponds to a fully charged condition of the power storage module.

7. The system of claim 3, wherein the input terminal of the switch module is configured to receive power from a local area power grid.

8. The system of claim 1, wherein the power converter is positioned to receive thermal energy from the combustion reaction.

9. The system of claim 1, wherein the power converter includes a thermoelectric element.

10. A method, comprising:

receiving thermal energy from a combustion reaction and converting a portion of the received thermal energy to electrical energy;

if a level of the converted electrical energy is above a first threshold, applying a first portion of the converted electrical energy to the combustion reaction;

if the level of the converted electrical energy is above a second threshold, greater than the first threshold, and if an amount of stored electrical energy in a storage device is below a first storage threshold, increasing the amount of stored electrical energy in the storage device by applying a second portion of the converted electrical energy to the storage device; and

if the level of the converted electrical energy is below the first threshold, applying a portion of the stored electrical energy to the combustion reaction.

11. The method of claim 10, comprising, if the level of the converted electrical energy is below the first threshold and the amount of stored electrical energy in the storage device is below a second storage threshold, lower than the first storage threshold, applying electrical energy from an external power source to the combustion reaction.

12. The method of claim 11, comprising, if the level of the converted electrical energy is above the second threshold and if the amount of stored electrical energy in the storage device is above the first storage threshold, applying the second portion of the converted electrical energy to the external power source.

13. A method, comprising:

receiving thermal energy from a combustion reaction;

converting the received thermal energy to locally generated electrical energy;

detecting a level of the locally generated electrical energy;

if the detected level of the locally generated electrical energy is below a first threshold, applying, to the combustion reaction, stored electrical energy from an energy storage device; and

if the detected level of the locally generated electrical energy is above the first threshold, applying only locally generated electrical energy to the combustion reaction.

14. The method of claim 13, comprising detecting a state-of-charge of the energy storage device, and wherein, if the detected state-of-charge of the energy storage device is below a first storage threshold and the detected level of the locally generated electrical energy is above a second threshold, greater than the first threshold, applying only locally generated electrical energy to the combustion reaction, and storing a portion of the locally generated electrical energy as stored electrical energy.

15. The method of claim 14, comprising, if the detected level of the locally generated electrical energy is below the first threshold and the detected state-of-charge of the energy storage device is below the first storage threshold, applying, to the combustion reaction, electrical energy from an external energy source.

16. The method of claim 15, wherein the applying electrical energy from an external energy source comprises applying electrical energy from a municipal power grid.

17. The method of claim 15, wherein applying electrical energy from an external energy source comprises applying electrical energy from a remotely-located energy storage device.

18. The method of claim 15, comprising, if the detected level of the locally generated electrical energy is above the second threshold and the detected state-of-charge of the energy storage device is above a second storage threshold, greater than the first storage threshold, transmitting a portion of the locally generated electrical energy to the external energy source.

19. The method of claim 13, wherein the detecting a level of the locally generated electrical energy comprises comparing a potential at an output of a power converter with a reference potential.