Simplified topology power converter for self-powered air conditioning system

Abstract

The invention relates to a simplified topological power converter for a self-powered air conditioning system. A power converter configured to supply power to an air conditioning system from one of an AC grid or an energy storage device, the power converter comprising: a positive DC line and a negative DC line; a first branch extending between the positive DC line and the negative DC line, the first branch including a first switch and a second switch; a second branch extending between the positive DC line and the negative DC line, the second branch including a third switch and a fourth switch; a third branch extending between the positive DC line and the negative DC line, the third branch including a fifth switch and a sixth switch; wherein the first branch circuit, the second branch circuit and the third branch circuit are one part of a three-phase inverter package; the AC power grid is connected to a junction point between the third switch and the fourth switch; and a controller.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application claims the benefit of U.S. Provisional Patent Application No. 63 / 627,707, filed on January 31, 2024, which is incorporated herein by reference in its entirety, and claims the benefit of U.S. Provisional Patent Application No. 63 / 688,593, filed on August 29, 2024, which is incorporated herein by reference in its entirety. Background Art

[0002] The embodiments described herein relate to air conditioning systems.

[0003] Electric energy drives a large number of devices and equipment in commercial, industrial, residential applications and data centers. For example, electric energy drives lights, motors, household appliances, medical equipment, computers, air conditioning systems, electric vehicle charging stations, data center processing and cooling needs, and many other electrical devices. In most areas, power utilities generate and distribute electricity (via the AC grid). Shortages and / or increased costs associated with factors such as the use of fossil fuels, the intermittent nature of renewable resources, power demand and supply variability, and increased energy demand significantly affect the cost and continuous availability of power to consumers and businesses. Generally speaking, shortages and / or increased costs often occur during times of peak demand. Peak demand can occur based on the time of day, such as in the morning or in the evening. On a more random basis, peak demand (or demand greater than the available supply) may occur due to natural disasters, or during long periods of time such as cloudy weather (if the power from the grid comes from solar energy) or wind variability (if the power from the grid comes from wind turbines). For example, a hurricane or earthquake may damage the generators and / or the power grid of a power utility, resulting in a significant loss of electrical power to commercial, industrial, and residential applications. Repairs to these damaged lines and generators may take hours, days, or weeks. Various sites may also lose power from the grid for other reasons, including maintenance. During these periods of power loss, the site may be unable to continue operating. In addition, the increasing number of data centers has significantly increased the demand for energy from the grid.

[0004] Often, electricity from the grid is more expensive during times of peak demand. For example, a utility may employ low-cost generators during periods of minimal demand, while further employing higher-cost generators during periods of peak demand. Unfortunately, existing infrastructure does not adequately address these different costs associated with peak and minimum demand. As a result, commercial, industrial, data center, and residential applications typically draw power from the grid during times of peak demand, regardless of the higher costs associated with generating it.

[0005] Some energy consumers, such as commercial, industrial, data center, and residential users, may be driven by factors other than cost, such as the desire to support sustainable energy options (as further described below). SUMMARY OF THE INVENTION

[0006] According to an embodiment, a power converter is configured to supply power from one of an AC grid or an energy storage device to an air conditioning system. The power converter includes: a positive DC line and a negative DC line; a first branch extending between the positive DC line and the negative DC line, the first branch including a first switch and a second switch; a second branch extending between the positive DC line and the negative DC line, the second branch including a third switch and a fourth switch; a third branch extending between the positive DC line and the negative DC line, the third branch including a fifth switch and a sixth switch; wherein the first branch, the second branch, and the third branch are part of a three-phase inverter package; a capacitor in parallel with the first branch, the second branch, and the third branch; the AC grid connected to a junction between the first switch and the second switch; the AC grid connected to a junction between the third switch and the fourth switch; a controller configured to control one or more of the first switch, the second switch, the third switch, the fourth switch, the fifth switch, and the sixth switch to supply power from one of the AC grid or the energy storage device to the air conditioning system.

[0007] In addition to, or as an alternative to, one or more of the features described herein, further embodiments may include: wherein the AC grid is connected to the junction between the first switch and the second switch via a reactor.

[0008] In addition to, or as an alternative to, one or more of the features described herein, further embodiments may include: wherein a positive terminal of the energy storage device is connected to a junction between the fifth switch and the sixth switch; and a negative terminal of the energy storage device is connected to the negative DC line.

[0009] In addition to, or as an alternative to, one or more of the features described herein, further embodiments may include: wherein the positive terminal of the energy storage device is connected to the junction between the fifth switch and the sixth switch via an inductor.

[0010] In addition to, or as an alternative to, one or more of the features described herein, further embodiments may include: wherein the controller operates the power converter in an AC-DC mode, in which power from the AC grid is used to charge the energy storage device.

[0011] In addition to one or more features described herein, or alternatively, further embodiments may include: wherein, the controller operates the power converter in a DC-AC mode, in which power from the energy storage device is supplied to the AC grid.

[0012] In addition to one or more features described herein, or alternatively, further embodiments may include: wherein, the positive terminal of the energy storage device is connected to the positive DC line; and the negative terminal of the energy storage device is connected to the negative DC line.

[0013] In addition to one or more features described herein, or alternatively, further embodiments may include: an air conditioning load connected to the junction point between the third switch and the fourth switch, and the air conditioning load connected to the junction point between the fifth switch and the sixth switch.

[0014] In addition to one or more features described herein, or alternatively, further embodiments may include: wherein, the air conditioning load is connected through a low-pass filter.

[0015] In addition to one or more features described herein, or alternatively, further embodiments may include: wherein, the controller operates the power converter in an AC-AC mode, in which power from the AC grid is used to power the air conditioning load.

[0016] In addition to one or more features described herein, or alternatively, further embodiments may include: wherein, the controller operates the power converter in a DC-AC mode, in which power from the energy storage device is supplied to the air conditioning load.

[0017] The foregoing features and elements may be combined in various combinations without exclusivity, unless otherwise expressly indicated. Given the following description and drawings, these features and elements and their operation will become more apparent. However, it should be understood that the following description and drawings are intended to be illustrative and explanatory in nature and non-limiting. Description of the Drawings

[0018] The present disclosure is illustrated by way of example and is not limited to the drawings, in which like reference numerals indicate similar elements.

[0019] Figure 1 A system in an exemplary embodiment is depicted.

[0020] Figure 2 Depicts the controller in an exemplary embodiment.

[0021] Figure 3A Depicts the electrical architecture in an exemplary embodiment.

[0022] Figure 3B Depicts the electrical architecture in an exemplary embodiment.

[0023] Figure 4A Depicts the electrical architecture in an exemplary embodiment.

[0024] Figure 4B Depicts the electrical architecture in an exemplary embodiment.

[0025] Figure 5A Depicts the electrical architecture of a constant speed compressor with a DC architecture in an exemplary embodiment.

[0026] Figure 5B Depicts the electrical architecture of a constant speed compressor with an AC architecture in an exemplary embodiment.

[0027] Figure 5C Depicts the electrical architecture of a variable speed compressor with a DC architecture in an exemplary embodiment.

[0028] Figure 5D Depicts the electrical architecture of a variable speed compressor with an AC architecture in an exemplary embodiment.

[0029] Figure 6 Depicts the electrical architecture of a compressor powered by a multilevel inverter in an exemplary embodiment.

[0030] Figure 7 Depicts a phase branch of a five-level multiphase inverter in an exemplary embodiment.

[0031] Figure 8 Depicts the communication between the controller, thermostat, and remote system in an exemplary embodiment.

[0032] Figure 9 Depicts the control process in an exemplary embodiment.

[0033] Figure 10 Depicts a power converter with a simplified topology in an exemplary embodiment.

[0034] Figure 11 Depicts a power converter with a simplified topology in an exemplary embodiment. Detailed Description

[0035] For current global electrification and decarbonization efforts, there is an encouragement to use efficient, optimized all-electric air conditioning systems that provide comfort while being dispatchable (on-off, adjustable, or variable) under different pricing conditions or after receiving a utility signal. By way of example, the utility signal can be received from the electrical AC grid and can include an Independent System Operator (ISO), which can include an independent, federally regulated entity established to coordinate regional transmission in a non-discriminatory manner and ensure the reliability and security of the power system; or a Regional Transmission Organization (RTO), which can operate most of the large electric power systems across a geographical area and is generally an independent, membership-based non-profit organization that ensures reliability and optimizes supply and demand bids for wholesale electric power or from a virtual power plant, which is generally considered to include the connected aggregation of integrated distributed energy (DER) technologies that provide demand flexibility and renewable energy. References to utilities refer to one or more entities involved in power generation, transmission, and / or distribution.

[0036] The embodiments described herein relate to an air conditioning system that includes an electrical energy storage system (e.g., a battery, a supercapacitor) to provide the level of dispatchability required for grid interconnection.

[0037] Figure 1 System 100 in an example embodiment is depicted. System 100 includes components of an air conditioning system. The phrase "air conditioning" is intended to include one or more of heating, cooling, ventilation, humidification, dehumidification, refrigeration, hot water heating, chilled water or fluid, air filtration, and other known air handling operations, or any combination of the operations above. The air conditioning system can include known types of systems such as heat pumps, ground source heat pumps, chillers, split systems, packaged systems, single package systems, etc. Air conditioning system 100 includes a first unit 200 and one or more second units 250. Depending on the nature of the air conditioning system, the first unit 200 and the (one or more) second units 250 can be located separately (indoors or outdoors) or co-located (indoors or outdoors). For example, in a split system, the first unit 200 is an outdoor unit (e.g., a compressor and a heat exchanger), and the (one or more) second units 250 are indoor units (e.g., an expansion mechanism, a heat exchanger). In a packaged system (e.g., rooftop or ground-mounted), the first unit 200 and the second unit 250 are co-located within a single footprint outside the building. In a chiller, the first unit 200 and the second unit 250 can be co-located (indoors or outdoors) or located separately. Some single package systems can have the first unit 200 and the second unit 250 co-located inside the building.

[0038] In Figure 1In the example shown, the first unit 200 can be an outdoor unit of a split system located on the ground plane next to the building 102, on the roof of the building 102, or any other location. The (one or more) second units 250 can be located inside the building 102 (as is common for split systems). It should be understood that Figure 1 is an example, and the embodiments are not limited to split systems.

[0039] System 100 includes a controller 220, a power converter 230, and an energy storage device (ESD) 240. Figure 1 are example embodiments, and the locations of the components are not limited to Figure 1 the locations shown. For example, the power converter 230, the energy storage device 240, and the controller 220 can be separate from the first unit 200 that houses the compressor 242, the drive 244, the fan 246, and the (one or more) loads 248. The first unit 200 can include a control unit (not shown) for controlling the operation of the first unit 200. This allows the components of the described embodiments to be retrofitted into an existing first unit 200 of an air conditioning system and / or an existing second unit 250 of an air conditioning system. One or more of the power converter 230, the energy storage device 240, and the controller 220 can be located in the first unit 200. One or more of the power converter 230, the energy storage device 240, and the controller 220 can be located outside the first unit 200 or adjacent to the first unit 200. One or more of the power converter 230, the energy storage device 240, and the controller 220 can be located in the building 102.

[0040] The first unit 200 can include a heat exchanger (not shown) that serves as a condenser / gas cooler and / or serves as an evaporator as part of a vapor compression refrigeration cycle.

[0041] In the figures, the locations of all components in the drawings are examples, and the embodiments include modifications to the locations of the components shown in the drawings. For example, a component shown as being connected to the first unit 200 can be a retrofit component added to an existing first unit 200. Although shown as separate boxes, elements can be incorporated into sub-assemblies and assemblies anywhere in the system (indoors or outdoors) without departing from the embodiments of the present disclosure.

[0042] The controller 220 can communicate with an air conditioning controller system controller and / or an energy storage device controller. In some embodiments, a single controller can implement all the functions of the controller 220, the air conditioning controller, and the energy storage device controller. The controller 220 communicates with the components of the described system using wired and / or wireless connections that are not shown in the drawings.

[0043] Figure 1 The system and its embodiments described herein allow one or more components of the air conditioning system and other loads not associated with the air conditioning system to be powered solely by the AC grid, solely by the energy storage device 240, and by a combination of the AC grid and the energy storage device 240. The one or more components of the air conditioning system include the components in the first unit 200 and the components in the second unit 250.

[0044] Figure 2 FIG. depicts a controller 220 according to an embodiment. The controller 220 includes a sensor interface 222 that can obtain operating parameters of the air conditioning system, such as pressure, temperature, etc. As is known in the art, the controller 220 can adjust the operation of the air conditioning system based on the sensed operating parameters. The controller 220 includes a processor 224 that controls the operation of the system 100. The processor 224 can be implemented using a general-purpose microprocessor that executes a computer program stored on a storage medium to perform the operations described herein. Alternatively, the processor 224 can be implemented in hardware (e.g., ASIC, FPGA) or in a combination of hardware / software. The processor 224 allows the controller 220 to perform local calculations, also known as edge computing. The processor 224 can send commands to other components of the air conditioning system 100 based on the results of the local calculations.

[0045] The controller 220 includes a memory 226 that can store computer programs, reference data, sensor data, etc. that can be executed by the processor 224. The memory 226 can be implemented using known devices, such as random access memory. The controller 220 includes a communication unit 228 that allows the controller 220 to communicate with other components of the system 100, such as the first unit 200, the second unit 250, and the thermostat 260. The communication unit 228 can be implemented using a wired connection (e.g., LAN, Ethernet, twisted pair, etc.) and / or a wireless connection (e.g., Wi-Fi, near field communication (“NFC”), Bluetooth, etc.).

[0046] In some embodiments, the communication unit 228 may provide high-speed data communication via an existing wiring system and / or provide communication with newer devices having high-speed buses while maintaining communication with existing devices (e.g., having an RS-485 communication bus). In some embodiments, the HVAC device may include four lines for data communication: power supply, ground, data +, and data -. Among these lines, data + and data - are used to carry low-speed standard RS-485 data. The power supply line is used to power the wall control and is from the second unit 250. This same power supply line is carried to the first unit 200, although it is generally not used. The ability to use the power supply line and the ground line of the four-wire system (referred to as "power line communication" (PLC) technology) allows digital / data signals to be sent through the power supply line. In some embodiments, PLC technology may allow data transfer at gigabit rates or near gigabit rates using standard two-wire cabling. This includes the two lines represented by the power supply and ground of the HVAC device. It should be appreciated that other data transfer speeds are possible. In some embodiments, the communication unit 228 of the present disclosure may be configured such that when PLC high-speed communication is occurring through the power supply line and the ground line of the four-wire system, low-speed RS-485 communication may also be occurring on the data + line and the data - line. In some embodiments, the ability to use high-speed communication or a combination of high-speed and low-speed communication enables the controller 220 to utilize machine learning (ML) or artificial intelligence (AI)-based algorithms. In some embodiments, high-speed and low-speed communication may occur approximately simultaneously (e.g., within a few milliseconds of each other). This may allow the standard HVAC line to communicate with both RS-485 controlled devices and HVAC devices containing additional PLC transceivers. This may be advantageous because both new high-speed HVAC devices and existing RS-485 HVAC devices can coexist on the existing wiring of a building.

[0047] Reference Figure 1 , the power converter 230 is used to perform any necessary power conversion, including one or more of AC-AC, AC-DC, DC-AC, and DC-DC. The power converter 230 may include several power converters at different locations in the system 100. The (one or more) power converters 230 may operate in a bidirectional manner such that one or more power conversions are bidirectional. As Figure 1As shown, power converter 230 is connected to an AC and / or DC power source and / or load. Power converter 230 can also supply power to loads in building 102, including second unit 250 (if in building 102), thermostat 260, and load 270. In a conventional mode, the loads in building 102 would receive AC power directly from the AC grid. Controller 220 can select whether the power will come from the AC grid or from power converter 230. Example embodiments of power converter 230 are described herein.

[0048] Energy storage device 240 is configured to provide at least a portion of the power to operate one or more of the components of the air conditioning system, such as first unit 200, (one or more) second units 250, along with (one or more) indoor loads 270 and any other loads, under certain circumstances. Energy storage device 240 can be implemented using devices for storing electrical energy, including, for example, one or more of batteries, battery modules, battery cells, supercapacitors, etc. Battery 240 can include several cells in a modular form or as a stand-alone multi-cell array. Battery 240 can be made up of a single or multiple self-contained systems, battery modules, or individual cells. Battery 240 (such as a complete plug and play battery) can include a case, wires, cells, and modules. For example, battery 240 can include a group of cells configured as a self-contained mechanical and electrical unit. Energy storage device 240 can include other components (e.g., ESD management system (ESDMS)), which is electrically coupled to energy storage device 240 and can be adapted to communicate with controller 220 directly or through the ESDMS.

[0049] First unit 200 also includes components that serve as part of the air conditioning system, and includes compressor 242, one or more drives 244, fan 246, and other loads 248, as well as a control unit (not shown). The heat exchanger (not shown) in first unit 200 can act as an evaporator or a condenser / gas cooler. These components are described in more detail herein when relevant to the embodiments.

[0050] In a split system, inside building 102, one or more second units 250 are positioned to condition one or more zones of building 102. A variety of known second units can be used to implement second unit 250, including variable air volume (VAV) units, liquid-cooled second units, fan coil units, furnaces, (one or more) air handlers, etc., which typically include a heat exchanger. In other types of systems (e.g., packaged systems or chiller systems), (one or more) second units 250 can be located outdoors and include any form of heat exchanger, such as a cooling tower, etc.

[0051] An optional thermostat 260 provides a user interface for the air conditioning system 100 and allows a user to input the operating mode of the air conditioning system 100, input set points for various zones of the system 100, etc. The indoor load 270 may be supplied with electrical power by the first unit 200. The indoor load 270 includes various loads such as appliances, lighting, electric vehicle chargers, etc. The thermostat 260 is not required, and other techniques may be used for controlling the air conditioning system.

[0052] Figure 3A An electrical architecture in an example embodiment is depicted. Figure 3A The positions of the components in are an example, and any of the components may be positioned as part of the first unit 200, part of the second unit(s) 250, or positioned separately from the first unit 200 or the second unit(s) 250. This allows components to be retrofitted into existing air conditioning systems. Although shown as separate boxes, elements may be incorporated into sub-assemblies and assemblies anywhere in the system (indoors or outdoors) without departing from the embodiments of the present disclosure.

[0053] As Figure 3A shown, the AC grid 302 is connected to the first unit 200 via a grid disconnect device 304 under the control of the controller 220. This allows the first unit 200 to be powered by the energy storage device 240 independently of the AC grid 302. The first unit 200 may also be powered by both the AC grid 302 and the energy storage device 240 in combination. The disconnect device 304 may also be implemented as a mechanical switch (e.g., controlled by the controller 220) or implemented using software (by the controller 220 by controlling one or more power converters).

[0054] The AC grid 302 is connected to indoor AC loads 308 (such as air handlers, or any fixtures in a residential, commercial, industrial building, or data center). The AC grid 302 is also provided to an AC / AC converter 310, which supplies regulated AC power to the compressor drive 244A of the compressor 242 and the fan 246. The AC / AC converter 310 may control the amplitude, frequency, and phase of the AC power supplied to the compressor drive 244A of the compressor 242 and the fan 246.

[0055] The AC power grid 302 can also be connected to one of the unidirectional or bidirectional AC / DC converters 312 that interface the AC power bus 305 with the DC power bus 313. The DC power bus 313 supplies power to the DC load 248, which may be located in the first unit 200. Under certain conditions, the DC power bus 313 supplies power to one or more components in the components of the air conditioning system (e.g., the compressor 242 and the fan 246) through the bidirectional AC / DC converter 312 and the AC / AC converter 310. This allows one or more components in the components of the air conditioning system to operate independently of or in combination with the AC power grid 302. The bidirectional AC / DC converter 312 also allows the power from the DC bus 313 to be directed to the AC power grid 302.

[0056] The DC power bus 313 can be powered by the energy storage device 240. In the charging mode, the DC power bus 313 is used to charge the energy storage device 240 (the charger is not shown). The DC power bus 313 can also be powered by one or more auxiliary DC sources 314, such as solar DC power, wind DC power, geothermal DC power, fuel cells, etc. The DC / DC converter 316 can be used to couple the auxiliary DC source 314 to the DC power bus 313. The DC power bus 313 can supply power to the indoor DC load 318. The DC / DC converter 320 can be used to couple the indoor DC load 318 to the DC power bus 313. The DC / AC converter 347 can be used to couple the DC power bus 313 to the indoor AC load 308 (through the disconnecting device 348). In some operating modes, the energy storage device 240 is used to supply power to the indoor AC load 308. The AC / AC converter 310, the AC / DC converter 312, the DC / DC converter 320, the DC / DC converter 316, and the DC / AC converter 347 can be Figure 1 implementations of the medium power converter 230. In some embodiments, the one or more auxiliary DC sources 314 are connected to the AC power bus 305 through a DC / AC converter (not shown). In other embodiments, the one or more auxiliary power sources provide AC power, which is connected to the AC bus 305 and / or the DC bus 313 through an appropriate AC / AC converter or AC / DC converter.

[0057] The compressor drive 244A can be implemented in various ways. In one embodiment, the compressor drive 244A is a switch, such as a contactor or a relay, that connects the compressor 242 to the output of the AC / AC converter 310. In other embodiments, the compressor drive 244A can be a power converter, such as an AC / AC converter or an AC / DC converter.

[0058] An optional DC / DC converter 241 can provide power conversion between the energy storage device 240 and the DC power bus 313. The DC / DC converter 241 can be a bidirectional converter for boosting or reducing the DC voltage, such that the energy storage device 240 can power the DC power bus 313 and the DC power bus 313 can charge the energy storage device 240. The DC / DC converter 241 can be part of the energy storage device 240 or can be a component separate from the energy storage device 240.

[0059] Figure 3A The electrical architecture of allows one or more components of the air conditioning system (the first unit 200 and / or one or more second units 250) to be powered only by the AC grid 302, only by the energy storage device 240, or by a combination of the energy storage device 240 and the AC grid 302. The power supplied by the AC grid 302 can be limited by a controller 220 that controls various power converters. Other loads such as the indoor DC load 318 and the indoor AC load 308 can be powered only by the AC grid 302, only by the energy storage device 240, or by both the energy storage device 240 and the AC grid 302. The one or more auxiliary DC sources 314 can also power one or more components of the air conditioning system (the first unit 200 and / or one or more second units 250) and / or other loads alone or in combination with the AC grid 302 and / or the energy storage device 240. Whether power is supplied from the AC grid 302, the energy storage device 240, the one or more auxiliary DC sources 314, or a combination thereof is based on various factors such as utility status, utility electricity rates, the state of the energy storage device 240, consumer preferences, etc. Example conditions are discussed below with reference to Figure 9 discusses example conditions.

[0060] Figure 3B depicts the electrical architecture in an example embodiment. Figure 3B The location of the components in is an example, and any of the components can be positioned as part of the first unit 200, part of one or more second units 250, or positioned separately from the first unit 200 or one or more second units 250. This allows components to be retrofitted to an existing air conditioning system. Although shown as separate boxes, elements can be incorporated into sub-assemblies and assemblies anywhere in the system (indoors or outdoors) without departing from the embodiments of the present disclosure.

[0061] Figure 3B Similar to Figure 3A, except that the AC / AC converter 310 is eliminated. The compressor 242 is supplied with power from the compressor drive 244A. The compressor drive 244A can be a switch, such as a contactor or a relay, that connects the compressor 242 to the AC power bus 305. In other embodiments, the compressor drive 244A can be a power converter, such as an AC / AC converter or an AC / DC converter. The compressor drive 244A can be controlled by the controller 220.

[0062] The fan 246 is supplied with power from the fan drive 244B. The fan drive 244B can be a switch, such as a contactor or a relay, that connects the fan 246 to the AC power bus 305. In other embodiments, the fan drive 244B can be a power converter, such as an AC / AC converter or an AC / DC converter. The fan drive 244B can be controlled by the controller 220.

[0063] Figure 3B The electrical architecture allows one or more components of the air conditioning system (the first unit 200 and / or the (one or more) second units 250) to be powered only by the AC grid 302, only by the energy storage device 240, or by a combination of the energy storage device 240 and the AC grid 302. The power supplied by the AC grid 302 can be limited by the controller 220 that controls various power converters. Other loads, such as the indoor DC load 318 and the indoor AC load 308, can be powered only by the AC grid 302, only by the energy storage device 240, or by both the energy storage device 240 and the AC grid 302. The one or more auxiliary DC sources 314 can also power one or more components of the air conditioning system (the first unit 200 and / or the (one or more) second units 250) and / or other loads alone or in combination with the AC grid 302 and / or the energy storage device 240. Whether power is supplied from the AC grid 302, the energy storage device 240, the one or more auxiliary DC sources 314, or a combination thereof is based on various factors, such as the utility status, the utility electricity price, the status of the energy storage device 240, the consumer preference, etc. Example conditions are discussed below with reference to Figure 9 Example conditions are discussed.

[0064] Figure 4A depicts the electrical architecture in another example embodiment. Figure 4AThe position of the components in the figure is an example, and any of the components can be positioned as part of the first unit 200, part of the second unit(s) 250, or positioned separately from the first unit 200 or the second unit(s) 250. This allows for retrofitting of components to an existing air conditioning system. Although shown as separate boxes, elements can be incorporated into sub-assemblies and assemblies anywhere in the system (indoors or outdoors) without departing from embodiments of the present disclosure.

[0065] In Figure 4A this, the compressor drive 244A and the fan 246 are DC powered and thus there is no need for an AC / AC converter 310. The bidirectional AC / DC converter 312 allows the energy storage device 240 to supply power to one or more components of the air conditioning system and / or feed power from the DC bus 313 to the AC grid 302 (under certain conditions). The bidirectional AC / DC converter 312 connects the AC power bus 305 to the DC power bus 313 through an interface.

[0066] The compressor drive 244A can be a switch, such as a contactor or a relay, that connects the compressor 242 to the DC power bus 313. In other embodiments, the compressor drive 244A can be a power converter, such as a DC / AC converter or a DC / DC converter. The compressor drive 244A can be controlled by the controller 220.

[0067] Figure 4A The electrical architecture allows one or more components of the air conditioning system (the first unit 200 and / or the second unit(s) 250) to be powered only by the AC grid 302, only by the energy storage device 240, or by a combination of the energy storage device 240 and the AC grid 302. The power supplied by the AC grid 302 can be limited by the controller 220 that controls various power converters. Other loads, such as the indoor DC load 318 and the indoor AC load 308, can be powered only by the AC grid 302, only by the energy storage device 240, or by a combination of the energy storage device 240 and the AC grid 302. The one or more auxiliary DC sources 314 can also supply power, alone or in combination with the AC grid 302 and / or the energy storage device 240, to one or more components of the air conditioning system (the first unit 200 and / or the second unit(s) 250) and / or other loads. Whether power is supplied from the AC grid 302, the energy storage device 240, the one or more auxiliary DC sources 314, or a combination thereof is based on various factors, such as utility status, utility electricity rates, the state of the energy storage device 240, consumer preferences, etc. Example conditions are discussed below with reference to Figure 9 are discussed.

[0068] Figure 4B depicts an electrical architecture in another exemplary embodiment. Figure 4B The location of the components in [description of the figure] is an example, and any of the components can be positioned as part of the first unit 200, part of the second unit(s) 250, or positioned separately from the first unit 200 or the second unit(s) 250. This allows for retrofitting of components to an existing air conditioning system. Although shown as separate boxes, elements can be incorporated into sub-assemblies and assemblies anywhere in the system (indoors or outdoors) without departing from the embodiments of the present disclosure.

[0069] Figure 4B Similar to Figure 4A , except that the fan 246 includes a fan drive 244B. The fan drive 244B can be a switch, such as a contactor or relay, that connects the fan 246 to the DC power bus 313. In other embodiments, the fan drive 244B can be a power converter, such as a DC / AC converter or a DC / DC converter. The fan drive 244B can be controlled by the controller 220.

[0070] Figure 4B The electrical architecture of [description of the figure] allows one or more components of the air conditioning system (the first unit 200 and / or the second unit(s) 250) to be powered only by the AC grid 302, only by the energy storage device 240, or by a combination of the energy storage device 240 and the AC grid 302. The power supplied by the AC grid 302 can be limited by the controller 220 that controls various power converters. Other loads, such as the indoor DC load 318 and the indoor AC load 308, can be powered only by the AC grid 302, only by the energy storage device 240, or by a combination of the energy storage device 240 and the AC grid 302. The one or more auxiliary DC sources 314 can also supply power, either alone or in combination with the AC grid 302 and / or the energy storage device 240, to one or more components of the air conditioning system (the first unit 200 and / or the second unit(s) 250) and / or other loads. Whether power is supplied from the AC grid 302, the energy storage device 240, the one or more auxiliary DC sources 314, or a combination thereof is based on various factors, such as utility status, utility electricity rates, the state of the energy storage device 240, consumer preferences, etc. Example conditions are discussed below with reference to Figure 9 discusses example conditions.

[0071] Figure 5A depicts the DC electrical architecture of the constant speed first unit 200 in an exemplary embodiment. Figure 5AThe location of the components in the middle is an example, and any of the components can be positioned as part of the first unit 200, part of the second unit(s) 250, or positioned separately from the first unit 200 or the second unit(s) 250. This allows the components to be retrofitted to an existing air conditioning system. Although shown as separate boxes, the elements can be added to sub-assemblies and assemblies anywhere in the system (indoors or outdoors) without departing from the embodiments of the present disclosure.

[0072] For ease of illustration and explanation, not all components of the first unit 200 are shown. The power converter 230 can be used in conjunction with the embodiments described above or other embodiments. For example, one or more auxiliary DC sources 314 can be connected (via a DC bus) to the energy storage device 240 to supplement the power from the energy storage device 240. As Figure 5A shown, AC power from the AC grid 302 is supplied to the power converter 230 through the grid disconnect device 304. The power converter 230 includes an AC / DC converter 370 and a DC / AC converter 372. The output of the DC / AC converter 372 is provided to the compressor 242 through the compressor drive 244A. Since the compressor 242 is a constant speed compressor, the compressor drive 244A can be a switch, such as a contactor or a relay.

[0073] Both the AC / DC converter 370 and the DC / AC converter 372 operate under the control of the controller 220. Between the AC / DC converter 370 and the DC / AC converter 372 is a DC link 371, which is optionally connected to the energy storage device 240 through a DC / DC converter 241. Under this arrangement, the energy storage device 240 can be charged by the power converter 230. Alternatively, the energy storage device 240 can supply DC power to the DC link 371 to power the DC / AC converter 372 and the compressor 242. This allows the first unit 200 to operate independently of the AC grid 302 or in combination with the AC grid 302. The AC / DC converter 370 can be bidirectional to allow the energy storage device 240 to supply power to the AC grid 302 and charge from the AC grid 302.

[0074] The controller 220, the power converter 230, the energy storage device 240, the DC / DC converters 320 and 316, and the DC / AC converter 347 and the DC / DC converter 241 can be retrofitted to the existing first unit 200. This allows the energy storage device 240 to be added to an existing air conditioning system to enable the first unit 200 to operate independently of the AC grid 302 or operate under the power from both the AC grid 302 and the energy storage device 240. It also allows auxiliary power sources to be added in a modular manner.

[0075] Figure 5A The electrical architecture allows one or more components of the air conditioning system (the first unit 200 and / or one or more second units 250) to be powered only by the AC grid 302, only by the energy storage device 240, or by a combination of the energy storage device 240 and the AC grid 302. The power supplied by the AC grid 302 can be limited by the controller 220 that controls various power converters. Other loads such as the indoor DC load 318 and the indoor AC load 308 can be powered only by the AC grid 302, only by the energy storage device 240, or by both the energy storage device 240 and the AC grid 302. The one or more auxiliary DC sources 314 can also power one or more components of the air conditioning system (the first unit 200 and / or one or more second units 250) and / or other loads alone or in combination with the AC grid 302 and / or the energy storage device 240. Whether the power is supplied from the AC grid 302, the energy storage device 240, the one or more auxiliary DC sources 314, or a combination thereof is based on various factors such as the utility status, the utility electricity price, the status of the energy storage device 240, the consumer preference, etc. Example conditions are discussed below with reference to Figure 9 discusses example conditions.

[0076] Figure 5B depicts the AC electrical architecture of the constant speed first unit 200 in an example embodiment. Figure 5B The location of the components in is an example, and any of the components can be positioned as part of the first unit 200, part of one or more second units 250, or positioned separately from the first unit 200 or one or more second units 250. This allows for retrofitting of components to an existing air conditioning system. Although shown as separate boxes, the elements can be incorporated into sub-assemblies and assemblies anywhere in the system (indoors or outdoors) without departing from the embodiments of the present disclosure.

[0077] For ease of illustration and explanation, not all components of the first unit 200 are shown. The power converter 230 can be used in combination with the embodiments described above or other embodiments. For example, one or more auxiliary DC sources 314 can be connected (via a DC bus) to the energy storage device 240 to supplement the power from the energy storage device 240.

[0078] In Figure 5BIn [the system], the power converter 230 includes a DC / DC converter 241 coupled to an energy storage device 240 and an AC / DC converter 370. The AC / DC converter 370 can be bidirectional to allow the energy storage device 240 to supply power to the AC grid 302 and to be charged from the AC grid 302. Since the compressor 242 is a constant speed compressor, the compressor drive 244A can be a switch, such as a contactor or a relay.

[0079] The controller 220, the power converter 230, and the energy storage device 240 can be retrofitted to the existing first unit 200. This allows the energy storage device 240 to be added to an existing air conditioning system to enable the first unit 200 to operate independently of the AC grid 302 or to operate under power from both the AC grid 302 and the energy storage device 240.

[0080] Figure 5B The electrical architecture [of the system] allows one or more components of the air conditioning system (the first unit 200 and / or one or more second units 250) to be powered only by the AC grid 302, only by the energy storage device 240, or by both the energy storage device 240 and the AC grid 302 in combination. The power supplied by the AC grid 302 can be limited by the controller 220 that controls the various power converters. Other loads, such as the indoor DC load 318 and the indoor AC load 308, can be powered only by the AC grid 302, only by the energy storage device 240, or by both the energy storage device 240 and the AC grid 302. The one or more auxiliary DC sources 314 can also power one or more components of the air conditioning system (the first unit 200 and / or one or more second units 250) and / or other loads alone or in combination with the AC grid 302 and / or the energy storage device 240. Whether power is supplied from the AC grid 302, the energy storage device 240, the one or more auxiliary DC sources 314, or a combination thereof is based on various factors, such as utility status, utility electricity rates, the state of the energy storage device 240, consumer preferences, etc. Example conditions are discussed below with reference to Figure 9 Example conditions are discussed below with reference to

[0081] Figure 5C depicts the DC electrical architecture of a variable speed first unit 200 in an example embodiment. Figure 5C The location of the components in [the figure] is an example, and any of the components can be positioned as part of the first unit 200, part of one or more second units 250, or positioned separately from the first unit 200 or one or more second units 250. This allows the components to be retrofitted to an existing air conditioning system. Although shown as separate boxes, the elements can be incorporated into sub-assemblies and assemblies anywhere in the system (indoors or outdoors) without departing from the embodiments of the present disclosure.

[0082] Figure 5C Similar to Figure 5A , except that the compressor drive 244A provides variable speed operation of the compressor 242. Other loads 248 of the first unit 200 may be powered from the output of the DC / AC converter 372.

[0083] The controller 220, the power converter 230, the energy storage device 240, and the DC / DC converter 241 may be retrofitted to an existing first unit 200. This allows the energy storage device 240 to be added to an existing air conditioning system to enable the first unit 200 to operate independently of the AC grid 302 or to operate under power from both the AC grid 302 and the energy storage device 240.

[0084] For purposes of illustration and explanation, not all components of the first unit 200 are shown. The power converter 230 may be used in combination with the embodiments described above or other embodiments. For example, one or more auxiliary DC sources 314 may be connected (via a DC bus) to the energy storage device 240 to supplement the power from the energy storage device 240.

[0085] Figure 5C The electrical architecture of allows one or more components of the air conditioning system (the first unit 200 and / or one or more second units 250) to be powered only by the AC grid 302, only by the energy storage device 240, or by a combination of the energy storage device 240 and the AC grid 302. The power supplied by the AC grid 302 may be limited by the controller 220 that controls the various power converters. Other loads such as the indoor DC load 318 and the indoor AC load 308 may be powered only by the AC grid 302, only by the energy storage device 240, or by both the energy storage device 240 and the AC grid 302. The one or more auxiliary DC sources 314 may also power, alone or in combination with the AC grid 302 and / or the energy storage device 240, one or more components of the air conditioning system (the first unit 200 and / or one or more second units 250) and / or other loads. Whether power is supplied from the AC grid 302, the energy storage device 240, the one or more auxiliary DC sources 314, or a combination thereof is based on various factors such as utility status, utility electricity rates, the state of the energy storage device 240, consumer preferences, etc. Example conditions are discussed below with reference to Figure 9 are discussed.

[0086] Figure 5D Depicts the DC electrical architecture of the variable speed first unit 200 in an example embodiment. Figure 5DThe position of the components in the middle is an example, and any of the components can be positioned as part of the first unit 200, part of the second unit(s) 250, or positioned separately from the first unit 200 or the second unit(s) 250. This allows the components to be retrofitted into an existing air conditioning system. Although shown as separate boxes, the elements can be incorporated into sub-assemblies and assemblies anywhere in the system (indoors or outdoors) without departing from the embodiments of the present disclosure.

[0087] Figure 5D Similar to Figure 5B , except that the compressor drive 244A provides variable speed operation of the compressor 242. Other loads 248 of the first unit 200 can be powered from the AC power bus 305.

[0088] For ease of illustration and explanation, not all components of the first unit 200 are shown. The power converter 230 can be used in combination with the embodiments described above or other embodiments. For example, one or more auxiliary DC sources 314 can be connected (via a DC bus) to the energy storage device 240 to supplement the power from the energy storage device 240.

[0089] The controller 220, the power converter 230, and the energy storage device 240 can be retrofitted into the existing first unit 200. This allows the energy storage device 240 to be added to an existing air conditioning system to enable the first unit 200 to operate independently of the AC grid 302 or operate under power from both the AC grid and the energy storage device 240.

[0090] Figure 5DThe electrical architecture allows one or more components of the air conditioning system (first unit 200 and / or one or more second units 250) to be powered only by the AC grid 302, only by the energy storage device 240, or by both the energy storage device 240 and the AC grid 302 in combination. The power supplied by the AC grid 302 can be limited by the controller 220 that controls various power converters. Other loads such as the indoor DC load 318 and the indoor AC load 308 can be powered only by the AC grid 302, only by the energy storage device 240, or by both the energy storage device 240 and the AC grid 302. The one or more auxiliary DC sources 314 can also power one or more components of the air conditioning system (first unit 200 and / or one or more second units 250) and / or other loads alone or in combination with the AC grid 302 and / or the energy storage device 240. Whether power is supplied from the AC grid 302, the energy storage device 240, the one or more auxiliary DC sources 314, or a combination thereof is based on various factors such as utility status, utility electricity price, the state of the energy storage device 240, consumer preferences, etc. Example conditions are discussed below with reference to Figure 9 Example conditions are discussed.

[0091] Figure 6 Depicts an electrical architecture with a variable speed compressor drive in an example embodiment, which includes a multilevel inverter. For ease of illustration and explanation, not all components of the first unit 200 are shown. Figure 6 The location of the components in is an example, and any of the components can be positioned as part of the first unit 200, part of the one or more second units 250, or positioned separately from the first unit 200 or the one or more second units 250. This allows components to be retrofitted into existing air conditioning systems. Although shown as separate boxes, elements can be incorporated into sub-assemblies and assemblies anywhere in the system (indoors or outdoors) without departing from the embodiments of the present disclosure.

[0092] As Figure 6 As shown in, AC power from the AC grid 302 is supplied to the power converter 230 through the grid disconnect device 304. The power converter 230 includes an AC / DC converter 380 and a multilevel inverter 382. The output of the multilevel inverter 382 is provided to the compressor 242. The output of the multilevel inverter 382 can be a multi-phase multilevel waveform configured to drive the multi-phase motor of the compressor 242. In an example embodiment, the multilevel inverter 382 is a five-level three-phase inverter. In another example embodiment, the multilevel inverter 382 is a three-level three-phase inverter.

[0093] The multilevel inverter 382 synthesizes a sinusoidal current waveform to operate and control the compressor 242. Traditionally, this has been accomplished by a two-level inverter. Integration with the energy storage device 240 allows for a natural progression to higher-order inverters. Three-level and five-level inverters require independent power supplies to set the voltage levels. In Figure 6 the embodiment of, the energy storage device 240 can set the voltage levels. The energy storage device 240 can include internally connected battery modules in series. The multilevel inverter 382 directly uses the battery modules for each required voltage level, thereby enabling the benefits of a multilevel inverter. The multilevel inverter 382 benefits from lower harmonic output and lower dv / dt device stress. The multilevel inverter 382 increases reliability through its ability to reconfigure to a lower number of levels (by integrating relays or back-to-back switches to connect or disconnect the battery modules) after a fault has occurred.

[0094] Figure 7 One phase leg of a five-level multiphase inverter in an embodiment of the multilevel inverter 382 is shown. The energy storage device 240 includes at least four battery modules 240A, 240B, 240C, and 240D connected in series. The combination of the battery modules 240A, 240B, 240C, and 240D and the neutral point n provides five voltage levels for creating a sinusoidal output waveform on one phase. Generally, using N battery modules provides an N + 1 level output waveform for each phase. The switches S1 - S4 and S1' - S4' are controlled by the controller 220 to generate a sine wave as known in the art. By integrating relays or back-to-back switches to connect or disconnect the battery modules, the multilevel inverter 382 can be reconfigured to fewer levels.

[0095] The voltage levels used in the multilevel inverter 382 do not need to be supplied by separate battery modules. The voltage levels for creating the sinusoidal output waveform can be created using one battery module (by splitting the battery voltage with a capacitor, for example).

[0096] Refer to Figure 6, both the AC / DC converter 380 and the multilevel inverter 382 operate under the control of the controller 220. Between the AC / DC converter 380 and the multilevel inverter 382 is a DC link 381, which is connected to the energy storage device 240. Under this arrangement, the energy storage device 240 can be charged by the power converter 230. Alternatively, the energy storage device 240 can supply DC power to the DC link 381 to power the multilevel inverter 382 and the compressor 242. This allows the first unit 200 to operate independently of the AC grid 302 or under power from both the AC grid 302 and the energy storage device 240. The AC / DC converter 380 can be bidirectional to allow the energy storage device 240 to supply power to the AC grid and charge from the AC grid.

[0097] Figure 6 The electrical architecture allows one or more components of the air conditioning system (the first unit 200 and / or one or more second units 250) to be powered only by the AC grid 302, only by the energy storage device 240, or by both the energy storage device 240 and the AC grid 302 in combination. The power supplied by the AC grid 302 can be limited by the controller 220 that controls the various power converters. Other loads such as the indoor DC load 318 and the indoor AC load 308 can be powered only by the AC grid 302, only by the energy storage device 240, or by both the energy storage device 240 and the AC grid 302. The one or more auxiliary DC sources 314 can also supply power to one or more components of the air conditioning system (the first unit 200 and / or one or more second units 250) and / or other loads alone or in combination with the AC grid 302 and / or the energy storage device 240. Whether the power is supplied from the AC grid 302, the energy storage device 240, the one or more auxiliary DC sources 314, or a combination thereof is based on various factors such as the utility status, the utility electricity price, the status of the energy storage device 240, consumer preferences, etc. Example conditions are discussed below with reference to Figure 9 discussed.

[0098] In the above embodiments, one or more auxiliary DC sources 314 can be used to provide DC power. The one or more auxiliary DC sources 314 can include sources such as solar DC power, wind DC power, geothermal DC power, fuel cells, etc.

[0099] Figure 8Depicts the communication between the controller 220, the thermostat 260, and the remote system 410 in an example embodiment. As pointed out above, the controller 220 can be integrated as part of an air conditioning controller and / or a battery controller, or be standalone and communicate with an air conditioning controller and / or an energy storage controller. The controller 220 communicates with the thermostat 260 via a local link 400. The local link 400 can be a wired connection (e.g., twisted pair, four-wire, power line communication, Modbus, CAN bus, etc.) and / or a wireless connection (e.g., WiFi, radio, or Bluetooth, NFC, etc.). The thermostat 260 can also be implemented using a software application operating on a user device (e.g., a mobile phone, a tablet computer, a laptop computer). The thermostat 260 can also provide occupancy, past performance, and weather information to the controller 220.

[0100] One or both of the controller 220 and the thermostat 260 can communicate with the remote system 410 via a network 406. The network 406 can be a long-distance network and can be implemented via various communication protocols. The network 406 can be implemented via one or more networks, such as but not limited to one or more of the following networks: WiMax, local area network (LAN), wireless local area network (WLAN), personal area network (PAN), campus area network (CAN), metropolitan area network (MAN), wide area network (WAN), wireless wide area network (WWAN), or any broadband network, and is further capable of implementing the following technologies, such as (by way of example): Global System for Mobile Communications (GSM), Personal Communication Service (PCS), Bluetooth, Wi-Fi, Matter, fixed wireless data, 2G, 2.5G, 3G (e.g., 3G network based on UMTS / WCDMA), 4G, IMT-Advanced, pre-4G, LTE-Advanced, 5G, 6G, Mobile WiMax, WiMax2, Wireless MAN Advanced network, Enhanced Data Rates for GSM Evolution (EDGE), General Packet Radio Service (GPRS), Enhanced GPRS, iBurst, UMTS, HSPDA, HSUPA, HSPA, HSPA+, UMTS-TDD, 1xRTT, EV-DO, messaging protocols, such as TCP / IP, SMS, MMS, Extensible Messaging and Presence Protocol (XMPP), Real-Time Messaging Protocol (RTMP), etc., Instant Messaging and Presence Protocol (IMPP), instant messaging, USSD, IRC, or any other wireless data network, broadband network, or messaging protocol.

[0101] The remote system 410 can be embodied as any type of processor-based computing or computer device capable of performing the functions described herein, including but not limited to computers, servers, workstations, desktop computers, laptop computers, notebook computers, tablet computers, mobile computing devices, wearable computing devices, network devices, web devices, distributed computing systems (such as cloud computing), processor-based systems, and / or consumer electronic devices. The remote system 410 provides information used by the controller 220 and / or the thermostat 260 to implement energy management routines that control how the one or more components of the air conditioning system and the load 270 consume power. The information provided by the remote system 410 can include utility pricing (which indicates the cost of electricity on the AC grid 302) and weather information (which can be used to predict future utility pricing and the use of the one or more components of the air conditioning system). Utility pricing and weather can be pushed to or pulled by the remote system 410 using known networking techniques. Utility pricing and / or weather can be determined in real time or be a forecast of future conditions.

[0102] In the embodiments described above, the controller 220 communicates with the components of the described system using wired and / or wireless connections (which are not illustrated in the figures). Depending on the power source used in the operating mode (e.g., one or more of AC grid power, energy storage device power, auxiliary power source, etc.), the controller 220 sends command signals to various system components (e.g., AC / DC converters 310, 312, DC / AC converter 347, DC / DC converters 320, 316, 241, AC / DC converter 370, DC / AC converter 372, AC / DC converter 380, and / or multilevel inverter 382, AC disconnect device 304, etc.) to route power to one or more components of the air conditioning system, such as the first unit 200, the (one or more) second units 250, along with the (one or more) indoor loads 270 and any other loads.

[0103] Figure 9Illustrates the energy management process in an exemplary embodiment. This process can be performed by the controller 220 and / or by the thermostat 260. At 600, the controller 220 determines whether there is a request to reduce energy usage, or whether there are any other communication signals, such as a change in energy pricing, or an incentive. A utility provider may request a reduction in energy usage during a specific time period to avoid service disruptions (e.g., brownouts) or other penalties or incentives, such as a change in pricing. A request to reduce energy usage may be accompanied by an incentive (e.g., a $5 credit on the next energy bill). A request for reduction may also originate from an energy consumer, such as a data center, where the data center needs to maintain its processing and / or cooling load and encourages other users to reduce their consumption to ensure energy availability.

[0104] If there is a request to reduce energy usage, the process proceeds to 602, where the user (e.g., a customer of the utility) can approve or reject the request to reduce energy usage. The approval or rejection determination can be pre-established by the user and pre-programmed into the controller 220 and / or the thermostat 260. For example, the user may wish to always reduce energy consumption regardless of the terms. The user may wish to never reduce energy consumption regardless of the terms. The user may wish to reduce energy consumption only when the utility offers an incentive. The approval or rejection determination at 602 can also be real-time, where the user inputs approval or rejection of the reduction in energy consumption through the thermostat 260 or through a mobile device.

[0105] If the user approves in 602 to reduce energy usage, the process proceeds to 604, where one or more components of the air conditioning system (if needed) and / or other loads are at least partially powered by the energy storage device 240. This may involve turning on the AC disconnect device 304 (e.g., the power from the AC grid 302 is zero), and only using the energy storage device 240 to power one or more components of the air conditioning system and / or other loads. Operating one or more components of the air conditioning system and / or other loads may also include using both the AC grid 302 and the energy storage device 240 in combination to power the one or more components of the air conditioning system and / or other loads. The controller 220 can limit the amount of power drawn from the AC grid 302 by controlling various power converters 230 in the system (e.g., AC / AC converter 310, AC / DC converter 312, DC / AC converter 347, DC / DC converter 320, DC / DC converter 316, DC / DC converter 241, AC / DC converter 370, DC / DC converter 372, AC / DC converter 380, and / or multilevel inverter 382) to reduce the amount of AC power drawn from the AC grid. The energy storage device 240 and the AC grid 302 are used in combination to power one or more components of the air conditioning system and / or one or more loads.

[0106] Using the energy storage device 240 to operate the one or more components of the air conditioning system may also include limiting the amount of power used from the AC grid 302 to a power limit (e.g., 1 kW over a 2-hour period). The controller 220 can limit the amount of power drawn from the AC grid 302 by controlling various power converters 230 in the system (e.g., AC / AC converter 310, AC / DC converter 312, DC / DC converter 320, DC / DC converter 316, DC / DC converter 241, AC / DC converter 370, DC / DC converter 372, AC / DC converter 380, and / or multilevel inverter 382) to reduce the amount of AC power drawn from the AC grid 302. At 604, other loads can be powered by the energy storage device 240, and the other loads include (one or more) indoor loads 270, which may include (one or more) indoor DC loads 318 and / or (one or more) indoor AC loads 308. The process returns to 600.

[0107] At some point, the energy storage device 240 will lack sufficient charge such that one or more components of the air conditioning system will need to be powered solely by the AC grid 302. The controller 220 can detect when the state of the energy storage device 240 (such as state of charge (SOC), state of health (SoH), voltage, temperature, etc.) is not within acceptable limits for powering one or more components of the air conditioning system or other loads. If the state of the energy storage device 240 is not within acceptable limits, then one or more components of the air conditioning system and / or other loads need to be powered by the AC grid 302. This results in interrupting the discharge of the energy storage device 240 and / or initiating charging of the energy storage device 240.

[0108] If the utility or some other source has not requested a reduction in energy usage at 600, the process proceeds to 606 where the controller 220 determines whether the system 100 should use power from the energy storage device 240. An example of a situation where the system 100 should use power from the energy storage device 240 occurs when the utility power is at peak price, near grid capacity, or at least one of in grid capacity. This determination can be made in real time or can be made in advance using a forecast and communicated from the utility to the air conditioning system. Peak price does not necessarily require the price of electricity to be at a maximum, but is generally known in the art as a period with a higher than average energy cost. Whether the utility is at peak price can be determined by utility pricing obtained from the remote system 410 or current or future weather information obtained from the remote system 410. This information can also be stored locally in the controller 220. If the utility is at peak price, near grid capacity, or at least one of in grid capacity, the process proceeds to 604 where one or more components of the air conditioning system and the load 270 (including the indoor AC load 308 and / or other loads) are powered by the energy storage device 240 alone or in combination with the AC grid 302. As noted above, the controller 220 can limit the amount of power drawn from the AC grid 302 by controlling various power converters 230 in the system. When determining that the system should use power from the energy storage device 240, peak price and grid capacity of the utility power are not the only factors that can be relied upon.

[0109] Regarding grid capacity, information about grid capacity and current grid load can be obtained from a remote system such as a source of utility pricing. If the AC grid 302 is at grid capacity or near grid capacity (e.g., within a threshold range of grid capacity and optionally increasing), it may be prudent to use power from the energy storage device 240 to avoid a power outage.

[0110] Another example of a situation where the system should use power from the energy storage device 240 occurs when the user requests a reduction in energy usage. The user can use the thermostat 260 to place the system 100 in a reduced energy usage mode (e.g., an eco-friendly mode), which causes the system to use power from the energy storage device 240 to power one or more components of the air conditioning system.

[0111] In another example, based on data from block 602 (e.g., user consent) or based on data from block 600 (e.g., a request to reduce energy usage), the system can use power from the energy storage device 240 based on machine learning (ML) and / or artificial intelligence (AI) control algorithms implemented by the controller 220.

[0112] If, at 606, the system should not use power from the energy storage device 240, the process proceeds to 608, where the energy storage device 240 uses the AC grid 302 to charge. At 610, the controller 220 determines whether the battery state is within acceptable limits, including the state of charge (SOC), state of health (SoH), temperature, voltage, or a state that exceeds safety and / or operating limits. If so, the process returns to 600. At 610, the controller 220 can detect parameters of the energy storage device 240 to confirm that parameters such as the health state of the battery, operating range, temperature range, voltage, capacity, etc. are within valid limits.

[0113] It should be noted that the energy storage device 240 can be charged even if the utility power is at peak price. This may include fault modes, test modes, etc. Therefore, charging the energy storage device 240 is not limited to off-peak utility power price times.

[0114] If, at 610, the energy storage device has a state that is not within acceptable limits, the process proceeds to 612, where the energy storage device 240 can be charged (if the SoC is low) or can be completely disconnected (if the energy storage device 240 is not operating within safety and / or operating limits).

[0115] Although Figure 9 involves operating one or more components of the air conditioning system and / or other loads to reduce power consumption, other techniques can also be used to reduce power consumption, such as using a variable speed drive to reduce the compressor speed, changing the thermostat set point, etc. In other embodiments, the utility can request an increase in energy usage. The request can be a real-time request or a future request based on predicted conditions. Increasing energy usage can include charging the energy storage device 240.

[0116] If the thermostat 260 is equipped with a processor 261, then Figure 9One or more operations of the process may be performed by thermostat 260. Processor 261 may be implemented using a general-purpose microprocessor that executes a computer program stored on a storage medium to perform the operations described herein. Alternatively, processor 261 may be implemented in hardware (e.g., ASIC, FPGA) or in a combination of hardware / software. Controller 220 and the thermostat may perform all or some of the operations in Figure 9 the operation.

[0117] In other embodiments, controller 220 and / or thermostat 260 perform system enhancement routines to improve the performance of the overall air conditioning system based on optimization (including model predictive control) or machine learning techniques, considering carbon impact, energy performance, energy cost, life cycle cost, impact on the life of the equipment, reliability. The system enhancement routines may operate with or without information about weather, occupancy, historical usage, customer preferences, equipment performance maps (HVAC, battery), likelihood of energy outages, etc. Machine learning techniques regarding customer preferences, usage, resilience of temperature decisions, cost, environmental issues, etc. may be used to improve control logic and optimization. Other control strategies with advantages regarding cost, performance, efficiency, environment, comfort, reliability (such as precooling and preheating) may be implemented by controller 220 and / or thermostat 260.

[0118] As described above, the embodiments employ various power converters, including DC-AC converters, AC-DC converters, AC-AC converters, and DC-DC converters, such as AC / AC converter 310, AC / DC converter 312, DC / AC converter 347, DC / DC converter 320, DC / DC converter 316.

[0119] Figure 10 Power converter 800 with a simplified topology is depicted in an example embodiment. Power converter 800 is a bidirectional AC-DC converter that connects AC grid 302 and energy storage device 240.

[0120] Power converter 800 includes three parallel branches 802, 804, and 806. Each branch 802, 804, and 806 extends between positive DC line 810 and negative DC line 812. Capacitor 814 extends between positive DC line 810 and negative DC line 812 and is parallel to each branch 802, 804, and 806.

[0121] Each of the branches 802, 804, and 806 includes a pair of switches connected in series and extending between a positive DC line 810 and a negative DC line 812. Branch 802 includes a first switch 822 and a second switch 832. Branch 804 includes a third switch 824 and a fourth switch 834. Branch 806 includes a fifth switch 826 and a sixth switch 836. The switches can be transistors, such as MOSFET devices, turned on and off by a controller 880. Branches 802, 804, and 806 can be implemented using off-the-shelf circuits, thus simplifying and streamlining the topology of the bidirectional AC-DC converter 800. In one embodiment, branches 802, 804, and 806 are implemented using a standard three-phase inverter package.

[0122] The AC grid 302 is connected to the first branch 802 at the junction of the first switch 822 and the second switch 832 through a reactor 840. The AC grid 302 is also connected to the second branch 804 at the junction of the third switch 824 and the fourth switch 834.

[0123] The positive DC terminal of the energy storage device 240 is connected to the third branch 806 at the junction of the fifth switch 826 and the sixth switch 836 through an inductor 842. The negative DC terminal of the energy storage device 240 is connected to the negative DC line 812.

[0124] The controller 880 is individually connected to each of the first switch 822, the second switch 832, the third switch 824, the fourth switch 834, the fifth switch 826, and the sixth switch 836 through control lines (not shown). The controller 880 can be implemented using a controller 220, a thermostat 260, or a similar processor-based control device that executes a computer program to perform the operations described herein.

[0125] In operation, the controller 880 sends control signals to one or more of the first switch 822, the second switch 832, the third switch 824, the fourth switch 834, the fifth switch 826, and the sixth switch 836 to control the power flow between the AC grid 302 and the energy storage device 240. In the AC-DC mode, the AC grid 302 is used to charge the energy storage device 240. In the AC-DC mode, the controller 880 controls one or more of the first switch 822, the second switch 832, the third switch 824, the fourth switch 834, the fifth switch 826, and the sixth switch 836 to operate the power converter 800 as an AC-DC converter to charge the energy storage device 240. In the DC-AC mode, the energy storage device 240 supplies power to the AC grid 302 (which can be directed to an air conditioning system). In the DC-AC mode, the controller 880 controls one or more of the first switch 822, the second switch 832, the third switch 824, the fourth switch 834, the fifth switch 826, and the sixth switch 836 to operate the power converter 800 as a DC-AC converter. In either mode, the control signals from the controller 880 can be pulse width modulation (PWM) signals.

[0126] Figure 10 Embodiments may use off-the-shelf circuitry (e.g., a three-phase inverter package) for branches 802, 804, and 806 such that the topology of the bidirectional AC-DC converter 800 is simplified and made easier.

[0127] Figure 11 Illustrates a power converter 900 with a simplified topology in an example embodiment. The power converter 900 operates both as an AC-AC converter and as a DC-AC converter to power an air conditioning load 901.

[0128] The power converter 900 includes three parallel branches 902, 904, and 906. Each branch 902, 904, and 906 extends between a positive DC line 910 and a negative DC line 912. A capacitor 914 extends between the positive DC line 910 and the negative DC line 912 and is in parallel with each branch 902, 904, and 906.

[0129] Each of the branches 902, 904, and 906 includes a pair of series-connected switches that extend between the positive DC line 910 and the negative DC line 912. Branch 902 includes a first switch 922 and a second switch 932. Branch 904 includes a third switch 924 and a fourth switch 934. Branch 906 includes a fifth switch 926 and a sixth switch 936. The switches can be transistors, such as MOSFET devices, that are turned on and off by a controller 980. Branches 902, 904, and 906 can be implemented using off-the-shelf circuitry, such that the topology of the power converter 900 is simplified and streamlined. In one embodiment, branches 902, 904, and 906 are implemented using a standard three-phase inverter package.

[0130] The AC grid 302 is connected to the first branch 902 at the junction of the first switch 922 and the second switch 932 through a reactor 940. The AC grid 302 is also connected to the second branch 904 at the junction of the third switch 924 and the fourth switch 934.

[0131] The positive DC terminal of the energy storage device 240 is connected to the positive DC line 910, and the negative DC terminal of the energy storage device 240 is connected to the negative DC line 912.

[0132] The air conditioning load 901 (e.g., an air conditioning compressor) is also connected to the second branch 904 at the junction of the third switch 924 and the fourth switch 934, and is connected to the third branch 906 at the junction of the fifth switch 926 and the sixth switch 936. A low-pass filter 903 can be placed between the air conditioning load 901 and the power converter 900.

[0133] The controller 980 is individually connected to each of the first switch 922, the second switch 932, the third switch 924, the fourth switch 934, the fifth switch 926, and the sixth switch 936 through control lines (not shown). The controller 980 can be implemented using a controller 220, a thermostat 260, or a similar processor-based control device that executes a computer program to perform the operations described herein.

[0134] In operation, the controller 980 sends control signals to one or more of the first switch 922, the second switch 932, the third switch 924, the fourth switch 934, the fifth switch 926, and the sixth switch 936 to control the power flow between the AC grid 302 and the air conditioning load 901 or between the energy storage device 240 and the air conditioning load 901. In the AC-AC mode, the AC grid 302 is used to power the air conditioning load 901. In the AC-AC mode, the controller 980 controls one or more of the first switch 922, the second switch 932, the third switch 924, the fourth switch 934, the fifth switch 926, and the sixth switch 936 to operate the power converter 900 as an AC-AC converter. In the DC-AC mode, the energy storage device 240 supplies power to the air conditioning load 901 (e.g., the air conditioning system compressor). In the DC-AC mode, the controller 980 controls one or more of the first switch 922, the second switch 932, the third switch 924, the fourth switch 934, the fifth switch 926, and the sixth switch 936 to operate the power converter 900 as a DC-AC converter. The control signal from the controller 980 can be a pulse width modulation (PWM) signal.

[0135] The second branch 904 is a shared branch for both AC-AC conversion and DC-AC conversion. The power converter 900 also provides a bi-directional power flow between the energy storage device 240 and the AC grid 302, enabling the energy storage device 240 to charge and discharge. The air conditioning load 901 is a load output that can incorporate a low-pass filter 903, which can directly power, for example, a motor.

[0136] Figure 11 Embodiments can use off-the-shelf circuits (e.g., three-phase inverter packages) for the branches 902, 904, and 906, such that the topology of the power converter 900 is simplified and made easier.

[0137] As described above, embodiments may take the form of processor-implemented processes and apparatus for practicing those processes (such as controller 220, controller 880, controller 908, and / or thermostat 260). Embodiments may also take the form of computer program code containing instructions embodied in a tangible medium, such as a network cloud storage device, an SD card, a flash drive, a floppy disk, a CD ROM, a hard drive, or any other computer-readable storage medium, wherein, when the computer program code is loaded into and executed by a computer, the computer becomes an apparatus for practicing the embodiments. Embodiments may also take the form of computer program code that is stored, loaded, and / or executed by a computer, or is transmitted through some transmission medium (such as through a wire or cable, through fiber optics, or via electromagnetic radiation), and when the computer program code is loaded into and executed by a computer, the computer becomes an apparatus for practicing the embodiments. When implemented on a general-purpose microprocessor, the computer program code segments configure the microprocessor to create specific logic circuits.

[0138] The terms used herein are for the purpose of describing particular embodiments only and are not intended to limit the disclosure. As used herein, the singular forms "a," "an," and "the" are also intended to include the plural forms unless the context clearly dictates otherwise. It will be further understood that the terms "comprises" and / or "comprising," when used in this specification, specify the presence of the 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.

[0139] Those skilled in the art will appreciate that various example embodiments are shown and described herein, each having certain features in a particular embodiment, but the disclosure is not limited thereby. Instead, the disclosure can be modified to incorporate any number of variations, alterations, substitutions, combinations, sub-combinations, or equivalent arrangements that have not been previously described but are commensurate with the scope of the disclosure. Additionally, while various embodiments of the disclosure have been described, it is to be understood that aspects of the disclosure may only include some of the described embodiments. Accordingly, the disclosure should not be regarded as limited by the foregoing description, but only by the scope of the appended claims.

Claims

1. A power converter configured to supply power from one of an AC grid or an energy storage device to an air conditioning system, the power converter comprising: A positive DC line and a negative DC line; A first branch extending between the positive DC line and the negative DC line, the first branch including a first switch and a second switch; A second branch extending between the positive DC line and the negative DC line, the second branch including a third switch and a fourth switch; A third branch extending between the positive DC line and the negative DC line, the third branch including a fifth switch and a sixth switch; Wherein the first branch, the second branch and the third branch are part of a three-phase inverter package; A capacitor in parallel with the first branch, the second branch and the third branch; The AC grid is connected to the junction between the first switch and the second switch; The AC grid is connected to the junction between the third switch and the fourth switch; A controller configured to control one or more of the first switch, the second switch, the third switch, the fourth switch, the fifth switch and the sixth switch to supply power from one of the AC grid or the energy storage device to the air conditioning system.

2. The power converter according to claim 1, wherein: The AC grid is connected to the junction between the first switch and the second switch through a reactor.

3. The power converter according to claim 1, wherein: The positive terminal of the energy storage device is connected to the junction between the fifth switch and the sixth switch; and The negative terminal of the energy storage device is connected to the negative DC line.

4. The power converter according to claim 3, wherein, The positive terminal of the energy storage device is connected to the junction between the fifth switch and the sixth switch through an inductor.

5. The power converter according to claim 3, wherein, The controller operates the power converter in an AC-DC mode, in which power from the AC grid is used to charge the energy storage device.

6. The power converter according to claim 3, wherein, The controller operates the power converter in a DC-AC mode, in which power from the energy storage device is supplied to the AC grid.

7. The power converter according to claim 1, wherein: The positive terminal of the energy storage device is connected to the positive DC line; And The negative terminal of the energy storage device is connected to the negative DC line.

8. The power converter according to claim 1, further comprising an air conditioning load connected to the junction between the third switch and the fourth switch, and the air conditioning load connected to the junction between the fifth switch and the sixth switch.

9. The power converter according to claim 8, wherein, The air conditioning load is connected through a low-pass filter.

10. The power converter according to claim 8, wherein, The controller operates the power converter in an AC-AC mode, in which power from the AC grid is used to power the air conditioning load.

11. The power converter according to claim 8, wherein, The controller operates the power converter in a DC-AC mode in which power from the energy storage device is supplied to the air conditioning load.

Images