Patent Application
20230420950
The present disclosure relates a generator system and, more particularly, relates to a backup power system configured to change an operating frequency of a natural gas generator to a driven frequency that is different from a grid frequency to aid in providing power to one or more loads.
This section provides background information related to the present disclosure which is not necessarily prior art. This section provides a general summary of the disclosure and is not a comprehensive disclosure of its full scope or all of its features.
A power outage can severely impact your productivity or disrupt critical operations. In some businesses, this can mean substantial financial losses, for example in data centers, manufacturers, agricultural, or scientific research. In some businesses, power loss can even endanger people's lives, for example in hospitals, mining companies, and construction companies. Data centers are an example of a business where uninterrupted power continuity is particularly important because computers may not withstand even a sub-second power interruption. Data centers are typically a building, a group of buildings, or other dedicated space that is used to house and functionally support computer systems and associated components for telecommunications, internet technologies, and/or data-storage systems. Although the term “data center” was originally used to denote spaces set aside to house or accommodate racks or trays of computer systems and servers, it has more recently been used to denote entire facilities that also house systems for Internet connectivity and, even more recently, cloud-based data storage.
Data centers can be disposed in one room of a building, on one or more floors of a building, or can encompass a plurality of buildings throughout a large complex or campus. Due to the varying configurations, power, cooling, and associated costs of operation may vary depending on the necessary infrastructure and backup systems. In some configurations, various mechanical infrastructure is necessary to provide heating, ventilation, and air conditioning (HVAC); humidification and dehumidification equipment; and other systems. Likewise, in some configurations, electrical infrastructure is typically necessary to support the operations of the data center and may include utility grid systems; electrical distribution, switching, and bypass systems from power sources; uninterruptible power supply (UPS) systems; power-backup systems; and other systems.
The drawings described herein are for illustrative purposes only of selected embodiments and not all possible implementations, and are not intended to limit the scope of the present disclosure.
Corresponding reference numerals indicate corresponding parts throughout the several views of the drawings.
Example embodiments will now be described more fully with reference to the accompanying drawings and appended claims. Numerous specific details are set forth such as examples of specific components, devices, and methods, to provide a thorough understanding of embodiments of the present disclosure. It will be apparent to those skilled in the art that specific details need not be employed, that example embodiments may be embodied in many different forms and that neither should be construed to limit the scope of the disclosure. In some example embodiments, well-known processes, well-known device structures, and well-known technologies are not described in detail.
The terminology used herein is for the purpose of describing particular example embodiments only and is not intended to be limiting. As used herein, the singular forms “a,” “an,” and “the” may be intended to include the plural forms as well, unless the context clearly indicates otherwise. The terms “comprises,” “comprising,” “including,” and “having,” are inclusive and therefore specify the presence of stated features, integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and/or groups thereof. The method steps, processes, and operations described herein are not to be construed as necessarily requiring their performance in the particular order discussed or illustrated, unless specifically identified as an order of performance. It is also to be understood that additional or alternative steps may be employed.
When an element or layer is referred to as being “on,” “engaged to,” “connected to,” or “coupled to” another element or layer, it may be directly on, engaged, connected or coupled to the other element or layer, or intervening elements or layers may be present. In contrast, when an element is referred to as being “directly on,” “directly engaged to,” “directly connected to,” or “directly coupled to” another element or layer, there may be no intervening elements or layers present. Other words used to describe the relationship between elements should be interpreted in a like fashion (e.g., “between” versus “directly between,” “adjacent” versus “directly adjacent,” etc.). As used herein, the term “and/or” includes any and all combinations of one or more of the associated listed items.
Although the terms first, second, third, etc. may be used herein to describe various elements, components, regions, layers and/or sections, these elements, components, regions, layers and/or sections should not be limited by these terms. These terms may be only used to distinguish one element, component, region, layer or section from another region, layer or section. Terms such as “first,” “second,” and other numerical terms when used herein do not imply a sequence or order unless clearly indicated by the context. Thus, a first element, component, region, layer or section discussed below could be termed a second element, component, region, layer or section without departing from the teachings of the example embodiments.
Spatially relative terms, such as “inner,” “outer,” “beneath,” “below,” “lower,” “above,” “upper,” and the like, may be used herein for ease of description to describe one element or feature's relationship to another element(s) or feature(s) as illustrated in the figures. Spatially relative terms may be intended to encompass different orientations of the device in use or operation in addition to the orientation depicted in the figures. For example, if the device in the figures is turned over, elements described as “below” or “beneath” other elements or features would then be oriented “above” the other elements or features. Thus, the example term “below” can encompass both an orientation of above and below. The device may be otherwise oriented (rotated 90 degrees or at other orientations) and the spatially relative descriptors used herein interpreted accordingly.
Overview
With particular reference to power sources and backup systems, it should be recognized that power is one of the largest recurring costs to the user of a data center and represents, in most cases, the single most important input to maintain operation. For example, power is required to run computing systems, servers, data storage, etc. as well as systems cooling the data center. As can be appreciated, continual and reliable operation of data centers are crucial for community and utility services, business services, government support and services, and other services, and such operation is typically predicated on supplying sufficient and reliable power.
Traditionally, data centers get primary electrical power from the wider municipal electric grid. The data center may further employ various transformers and/or electrical componentry to ensure that the incoming grid power maintains the proper voltage and/or frequency. Data centers may supplement and/or replace grid power using on-site electrical generation equipment, such as stand-alone generators. These generators can form a part of a UPS system.
UPS systems also serve as an initial backup, in case of a power outage or similar issue. A typical UPS system can provide power to critical components for up to about five minutes to provide sufficient time to bring backup power generation systems online following an outage or similar issue with the wider electric grid power source.
In order to ensure continuous uptime and minimize outages as much as possible, most data centers have a backup power source on site or nearby. More often than not, backup power supply comes from a fuel generator, itself powered by gasoline or diesel, which typically output about 600 kW of power. However, natural gas systems are particularly desirable due to operational concerns (e.g., availability of fuel), reduced emissions, and cost reduction considerations.
However, it has been found that such large natural gas generators (e.g., larger than 1500 kW) and/or combined generator and UPS systems do not meet the required needs during a power ramp-up cycle as power is switched from grid power to natural gas generators. That is, as illustrated in
Accordingly, there exists a need for a power backup system that is configured to provide backup power to meet the power demands of a data center in the event of loss of a primary power source. Additionally, there exists a need to provide a power backup system that is operable using natural gas to address operational concerns, reduce emissions, and reduce operational costs. A natural gas power backup system may produce power at a lower rate and/or with lower emissions than grid power and thus may also enable significant financial gains through load curtailment and/or to sell excess power to the grid, which data centers with conventional power backup systems cannot benefit from.
Therefore, according to the principles of the present teachings, a backup power system is provided having advantageous construction for supplying power to at least one load. The load is normally connected to grid power at a grid frequency. The backup power system includes a generator powered by a fuel in gas phase, such as natural gas; a power controller operably coupled to the generator configured to control an operating frequency of the generator; the power controller is configured to be coupled to the load, wherein the power controller is configured to output a generator control signal to the generator upon loss of the grid power to change an operating frequency of the generator to a predetermined driven frequency greater than the grid frequency, and wherein the power controller is configured to selectively couple the at least one load to the generator at the predetermined driven frequency.
Additionally, according to the principles of the present teachings, a method of providing a backup power system is provided to supply power to at least one load. The load is normally connected to grid power at a grid frequency. The method includes providing a generator powered by a fuel in gas phase, such as natural gas; detecting loss of grid power to the load; driving the generator to an operating frequency equal to a predetermined driven frequency that is greater than the grid frequency; and selectively coupling the at least one load to the generator via a power controller while the generator is at the predetermined driven frequency.
Backup Power System
In accordance with the teachings of the present disclosure, and with reference to
As illustrated in
With continued reference to
With particular reference to
In some embodiments, the power controller 14 is operably coupled to the generator 12 and configured to control one or more operating parameters of the generator 12. In some embodiments, the power controller 14 can initiate a start-up cycle in the generator 12, can terminate operation of the generator 12, can vary one or more operational settings of the generator 12 (e.g., a power output, a running frequency and thus geared output frequency, and the like), or otherwise sense, detect, and/or monitor one or more conditions of the generator 12. In some embodiments, the power controller 14 is configured to output a generator control signal to the generator 12 to control an operation of the generator 12. In some embodiments, the power controller 14 is configured to receive a generator response signal from the generator 12 indicative of a parameter of the generator 12, such as, for example, an operating frequency of the generator 12. In some embodiments, the power controller 14 can comprise an integrated grid sensor 22 operably coupled directly and/or indirectly to grid power 200 to sense, detect, or otherwise determine status and/or loss of grid power 200. A grid sensor 22 can output a grid signal to the power controller 14 in response to or indicative of loss of grid power 200. It should be understood that in some embodiments the grid sensor 22 can be incorporated in and made a part of the power controller 14 (illustrated generally as the combined box having reference number 14a in
In some embodiments, the power controller 14 is operably coupled to the load controller bus 16. In some embodiments, a load controller bus 16 is provided and operably coupled between the generator 12, grid relay 18, and UPS to receive electrical power from at least one of the generator 12, grid power 200, and UPS 20 for distribution to one or more loads 100 (100a, 100b, 100c, . . . , 100n). In some embodiments, the grid and generator may be connected to a generator utility bus 24 ahead of the load controller bus 16. The power controller 14, in some embodiments, is configured to communicate with the load controller bus 16 to selectively control coupling and decoupling of each of the individual loads 100 from electrical power supplied by the generator 12, grid power 200, and/or UPS 20. For example, during a failure of grid power 200 the essential data center load 100a may be coupled to the electrical power supplied by the UPS 20, while the HVAC load 100c may be decoupled from the electrical power supplied by the UPS 20. Other examples exist.
In some embodiments, a grid relay 18 is operably coupled between the grid power 200 and the generator utility bus 24. The grid relay 18 is configured to selectively control coupling and decoupling of the generator utility bus 24 and grid power 200. In some embodiments, the grid relay 18 is configured to receive a relay signal from the power controller 14 to selectively open the grid relay 18 upon detection of failure of grid power 200 and/or selectively close the grid relay 18 upon detection of presence of grid power 200. In this way, the grid relay 18, responsive to the power controller 14, can selectively provide grid power 200 to the load controller bus 16, and/or loads 100.
In some embodiments, the UPS 20 is operably coupled between the power controller 14 and the load controller bus 16. The UPS 20 is configured to automatically provide stored electrical power to the load controller bus 16 in response to loss of grid power 200. In some embodiments, the UPS 20 comprises a battery system configured to provide temporary power to the load controller bus 16 at a frequency generally equal to grid frequency. In some embodiments, the UPS 20 is responsive to a UPS control signal from the power controller 14 and can output a UPS status signal to the power controller 14 indicative of an operational status, such as ON/OFF, power delivery, power output, output frequency, temperature, and the like.
At Step 310 a loss of grid power 200 is detected, sensed, and/or otherwise determined. In some examples, the one or more grid sensors 22 can detect, sense, and/or determine when disruption, cessation, or partial loss of grid power 200 from primary power source 210 occurs, and transmit an indication of the status of grid power 200 to the power controller 14. The indication may be, for example, transmitted to the power controller 14 via a dedicated control wire or bus connecting the one or more grid sensors 22 to the power controller 14. In some examples, once the loss of grid power 200 is determined, an indication of the loss of grid power 200 is transmitted from the power controller 14 to the mechanical controller 15 to initiate a mechanical procedure for power failure (described in more detail below with reference to
At Step 312, the power controller 14 can initiate a switchover process with the generator 12. In one example, the power controller 14 can output a relay signal to the grid relay 18 to disconnect (e.g., open the grid relay 18) the load controller bus 16 (and/or one or more loads 100a, 100b, 100c, . . . , 100n) from grid power 200. Additionally, the power controller 14 can transmit a generator control signal to the generator 12 to initiate a generator startup sequence. It should be understood that the generator 12 may require non-zero time to achieve one or more proper operating parameters, including but not limited to temperature, pressure, output frequency, output voltage, operating speed (rpm), and the like, prior to connecting the generator 12 to the load controller bus 16 (and/or one or more loads 100a, 100b, 100c, . . . , 100n).
At Step 314, the power controller 14 can output a generator control signal to the generator 12 to drive the generator 12 to an intermediate output frequency. The generator control signal may be, for example, transmitted to the generator 12 via a dedicated control wire or bus connecting the generator 12 to the power controller 14. In one example, the power controller 14 can output a generator control signal to the generator 12 to drive the generator 12 to a driven frequency above the nominal operating frequency of grid power 200. For example, for applications in the United States with a nominal operating frequency of 60 Hz, the driven frequency can be approximately 61.5 Hz, or within a range of approximately 61 Hz to 62 Hz. In another example, for applications outside of the United States with a nominal operating frequency of 50 Hz the driven frequency can be approximately 51.5 Hz, or within a range of approximately 51 Hz to 52 Hz. In this way, it should be understood that the power controller 14 is outputting a generator control signal to the generator 12 to drive the generator 12 to a driven frequency that is different from the grid operating frequency of the associated grid power 200. Thus, in some embodiments, the power controller 14 can output a generator control signal to the generator 12 to drive the generator 12 to a driven frequency that is greater than the grid operating frequency. In some examples, the power controller 14 controls a generator governor that controls a rotational speed of the generator 12, such as to a speed of about 1537 rpm, for example, which results in a frequency of about 61.5 Hz. In some embodiments, the generator 12 can output a generator signal to the power controller 14 indicative of the actual or current operating frequency of the generator 12 to provide feedback control of the generator 12 by the power controller 14. Upon determination that actual operating frequency of the generator 12 sufficiently meets a predetermined frequency, the power controller 14 can cause a generator breaker to close (not shown) to operably couple the generator 12 to the load controller bus 16.
At Step 316, the power controller 14 can notify the UPS 20 of loss of grid power 200. The UPS 20 can supply power from its battery system or other power storage system to the load controller bus 16 to provide power to loads 100 via power controller 14. UPS 20 can continue to supply power to load controller bus 16 until the generator 12 and/or main power is restored. Operation of the UPS 20 may be time limited (e.g., 5 minutes) due to heat, capacity, and/or other operational limits.
At Step 318, the power controller 14 can further receive a UPS status signal indicating the operating status of UPS 20 (i.e., that the UPS has finished loading). In response to generator signal, UPS status signal, and/or a predetermined time delay, power controller 14 can begin a modified ramp transition process of transitioning loads 100a, 100b, 100c, and/or 100n to be driven by generator 12 at the driven frequency. This modified ramp transition process continues until load is moved from UPS 20 to generator 12. While maintaining the driven frequency during this modified ramp transition, conventional UPS frequency of a lower frequency (e.g., 55 Hz) is avoided thereby preventing a trip condition of generator 12 and enabling continued operation of generator 12. In some embodiments, UPS 20 and/or power controller 14 can monitor frequency and if the frequency is below a predetermined frequency, such as 61.0 Hz, can pause offload from UPS 20 to generator 12 until frequency increases above 61.0 Hz. In some embodiments, cooling fluid or water can be opened. Upon detection of completion of modified ramp transition from UPS 20 to generator 12 (such that a load on UPS 20 is zero), which can be indicated by the opening of relays or contacts or output of the UPS status signal, ancillary loads (e.g., load not typically carried or powered by UPS 20) can be brought online and carried by generator 12. These ancillary loads can include various HVAC loads 100c or other loads 100n. Once generator 12 is fully loaded, additional systems, such as chillers, can be activated, including switching valves to flow water from chillers direct to data hall, maintaining cooling to data hall computer room air handlers (CRAHs) until a temperature difference (13° F.) is achieved, and then modulating valves between mixing stored water back into return to be chilled until tank water and supply water are within 2° F.
In Step 320, power controller 14 drives the frequency of generator 12 back to the grid frequency (e.g., 60 Hz) and outputs the UPS control signal to indicate generator 12 is fully operational and UPS 20 is deactivated. In some embodiments, UPS 20 can again set an acceptable frequency band (e.g., 55-60 Hz).
At Step 322, grid sensor 22 and/or power controller 14 can monitor grid power 200 to determine if grid power 200 has returned and/or is stable. If grid power 200 has not returned or does not have the required output, voltage, frequency, and/or stability, grid sensor 22 and/or power controller 14 can continue to monitor grid power 200 until otherwise. If grid power 200 has returned and provides the required output, voltage, frequency, and/or stability, then a soft load back to grid power 200 can be initiated.
In Steps 324 and 326, power controller 14 can begin a soft load back to grid power 200 by discontinuing a UPS control signal (e.g., “loss of utility/on generator”). In some embodiments, power controller 14 can bring loads 100a, 100b, 100c, . . . , 100n on grid power 200 by actuating grid relay 18 through a conventional process. It should be recognized that the frequency of generator 12, during the soft load process, is generally equal to the frequency of grid power 200. Once complete, power controller 14 can return to a monitoring condition for further detection of loss of grid power.
In block 508, the mechanical controller 15 receives an indication of loss of grid power from the power controller 14. The indication may be, for example, transmitted to the mechanical controller 15 via a dedicated control wire or bus connecting the mechanical controller 15 to the power controller 14. In some examples the mechanical controller 15 is the same controller as the power controller 14. As mentioned above with reference to
In one example, with reference to the mechanical system 400 of
In block 510, the mechanical controller 15 may cause the valves to the chillers 420 to be opened to allow coolant to flow through all of the chillers even though the chillers are not receiving electrical power. With reference to the mechanical system 400 of
In block 512, the mechanical controller 15 determines if the generator is fully online (see, for example, block 322 of
In block 514, the mechanical controller 15 may cause the chillers to be started sequentially to avoid overloading the system. With reference to
In block 516, the mechanical controller 15 determines if the coolant temperature has reached a threshold indicating the mechanical system 400 is effectively cooling the CRAHs. This can be determined, for example, by comparing the measured temperature by temperature sensor T1 with a temperature threshold value.
In block 518, once the temperature has reached a threshold, the system transitions coolant back to the storage tanks. With reference to
The foregoing description of the embodiments has been provided for purposes of illustration and description. It is not intended to be exhaustive or to limit the disclosure. Individual elements or features of a particular embodiment are generally not limited to that particular embodiment, but, where applicable, are interchangeable and can be used in a selected embodiment, even if not specifically shown or described. The same may also be varied in many ways. Such variations are not to be regarded as a departure from the disclosure, and all such modifications are intended to be included within the scope of the disclosure.
