WO2024221036A1

WO2024221036A1 - A system for inverter air conditioner power consumption reduction

Info

Publication number: WO2024221036A1
Application number: PCT/AU2024/050360
Authority: WO
Inventors: Christopher Rogerson
Original assignee: Christopher Rogerson
Priority date: 2023-04-25
Filing date: 2024-04-16
Publication date: 2024-10-31

Abstract

The present disclosure describes a system that lowers the energy use of inverter air conditioners using a controller with an input/output (I/O) interface that connects to the air conditioner's control terminals, such as Demand Response Enabling Device (DRED) terminals. The controller incorporates a processor to manage an operational controller and a memory device to store control parameters that direct the operational controller's actions in adjusting the air conditioner's functions. These parameters correspond to specific temperature and power demand categories and align with phases like start-up and ongoing operations. The operational controller determines the right categories using readings from temperature and current sensors, then modulates the air conditioner's settings by applying these parameters and manipulating the I/O interface to control the compressor's activity. This method enhances energy efficiency by adapting the air conditioner's operations to various environmental and power conditions.

Description

A system for inverter air conditioner power consumption reduction

Field of the Invention

[0001 ] This invention relates generally to system designed to reduce energy consumption of an inverter air conditioner.

Background

[0002] Inverter air conditioners represent a significant advancement in climate control technology, primarily distinguished by their ability to regulate the speed of the compressor motor to continuously adjust the temperature. Unlike traditional air conditioners that operate with a fixed speed compressor, which repeatedly turns on and off to maintain the desired temperature, inverter air conditioners vary the compressor speed without the need for complete shutdowns. This continuous operation mode not only ensures a more stable room temperature but also enhances energy efficiency as the compressor consumes power proportional to the actual cooling demand.

[0003] The ability to modulate compressor speed allows inverter air conditioners to significantly reduce energy consumption compared to conventional units. This reduced energy consumption is crucial in the context of global energy efficiency efforts and greenhouse gas reduction.

[0004] This makes inverter air conditioners an essential component of modern efforts to combat climate change by improving the energy efficiency of building heating, ventilation, and air conditioning (HVAC) systems. Thus, optimising the performance of inverter air conditioners to further reduce their energy consumption is a critical area of focus in environmental sustainability strategies.

Summary of the Disclosure

[0005] There is provided herein a system configured to reduce energy consumption of inverter air conditioners. The system has a controller having an I/O interface interfacing control terminals (preferably Demand Response Enabling Device (DRED) or Demand control terminals for some types of air conditioners) of an inverter air conditioner. In some countries such as Australia and New Zealand, DREDs allow regulating authorities to limit the power that an air conditioner can consume on demand.

[0006] The controller comprises a processor executing an operational controller and has a memory device storing control parameters. The control parameters are used by the operational controller to control operation of the air conditioner to reduce energy consumption.

[0007] The control parameters are stored in relation to temperature categories (such as high and low temperature categories) and power demand categories (such as high, intermediate and low-power demand categories).

[0008] In embodiments, the control parameters may be further stored in relation to cycles (such as a start-up cycle and a continual operational cycle).

[0009] The operational controller is configured to determine a temperature category (such as by taking a temperature reading from a temperature sensor operably coupled to the I/O interface) and determine a power demand category (such as by taking a current draw reading of the air conditioner from a current sensor operably coupled to the I/O interface).

[0010] The operational controller is configured to load control parameters according to the temperature and power demand categories, and to control operation of the air conditioner by controlling the I/O interface to inhibit a compressor of the air conditioner according to the control parameters.

[001 1 ] In this way, the operational controller reduces power consumption of the air conditioner.

[0012] Furthermore, timing for the control parameters may be configured according to the temperature and power demand categories and, in embodiments, the cycle.

[0013] For example, timing for the low temperature category and continual operational cycle may be less than that of the high-temperature category. Furthermore, timing for the continual operational cycle may be greater than that of the start-up cycle for both low and high temperature categories.

[0014] Other aspects of the invention are also disclosed. Brief Description of the Drawings

[0015] Notwithstanding any other forms which may fall within the scope of the present invention, preferred embodiments of the disclosure will now be described, by way of example only, with reference to the accompanying drawings in which:

[0016] Figure 1 shows a system for inverter air conditioner power consumption reduction; and

[0017] Figure 2 shows a control algorithm executed by an operational controller of the system of Figure 1 .

Description of Embodiments

[0018] Figure 1 shows a system 100 configured for inverter air conditioner power consumption reduction. The system 100 comprises a controller 101 having an I/O interface 110 interfacing control terminals 114 (preferably Demand Response Enabling Device (DRED) or Demand control terminals for some types of air conditioners) of an inverter air conditioner 113.

[0019] The controller 101 comprises a processor 102 for processing digital data. The controller 101 further comprises a memory device 103 in operable communication with the processor 102 via a system bus. In use, the processor 102 is configured to fetch, decode and execute computer program code instructions and associated data 105 from the memory device 103.

[0020] The memory device 103 is configured to store control parameters 106. These control parameters 106 are stored in relation to temperature categories 107 and power demand categories 108. Preferably, these control parameters 106 may further be stored in relation to cycles 109.

[0021 ] The computer program code instructions may be logically divided into a plurality of computer program code instruction controllers executed by the processor 102. One such controller may be an operational controller 104 configured to control the operation of the air conditioner 113 via the I/O interface 110 in the manner described herein to reduce power consumption of the air conditioner 113.

[0022] The controller 101 may further interface a temperature sensor 11 1 via the I/O interface 110 to monitor outside air temperature. [0023] The controller 101 may further interface a current sensor 1 12 via the I/O interface 1 10 to monitor power consumption of the air conditioner 1 13. As shown, the current sensor 112 may measure current between an AC power source 116 and the compressor 115 of the air conditioner 1 13.

[0024] Figure 2 shows a control algorithm 200 implemented by the operational controller 104 in accordance with an exemplary embodiment.

[0025] At step 201 , the operational controller 104 may detect operation of the air conditioner 1 13. The operational controller 104 may detect operation of the air conditioner 114 by detecting a current draw of more than 1 amp for more than 15 minutes using the current sensor 112.

[0026] At step 202, the operational controller 104 may determine a temperature category 202.

[0027] In embodiments, the temperature category comprises a low temperature category (i.e., when external temperature is low so that the air conditioner 1 13 is heating) and a high temperature category (i.e., when external temperature is high so that the air conditioner 113 is cooling). In embodiments, the low temperature category may be for outside air temperatures of less than 15°C.

[0028] At step 203, the operational controller 104 is configured to determine a power demand category 203. The power demand category 203 represents the power demand of the compressor 1 15 of the air conditioner 113. For example, in extreme temperatures, the air conditioner 113 will draw more current as opposed to in moderate temperatures.

[0029] As alluded to above, the controller 101 may be configured to determine the power demand category by taking a current reading using the current sensor 112.

[0030] During initial setup, the controller 101 may be configured with a maximum current draw specific to the air conditioner.

[0031 ] The power demand category may comprise a high-power demand category wherein the air conditioner 1 13 draws more than 75% of the maximum current draw. The power demand category may further comprise an intermediate-power demand category wherein the air conditioner draws between approximately 50% and 75% of the maximum current draw. The power demand category may further comprise a low- power demand category wherein the air conditioner 1 13 draws less than approximately 50% of the maximum current draw.

[0032] In embodiments, at step 204, the operational controller 104 may determine an operational cycle 109.

[0033] The operational cycles 109 may comprise a start-up cycle which commences first after detecting operation at step 201 and which is followed by a continual operational cycle 109.

[0034] The controller 101 may be configured to operate the start-up cycle 109 for a set period, such as 30 minutes.

[0035] At step 205, the operational controller 104 is configured to load control parameters 106 according to the power demand and temperature categories and the cycle determined at steps 202 - 204.

[0036] At step 206, the operational controller 104 is configured to control operation of the air conditioner 1 13 by controlling the I/O interface 1 10 to inhibit the compressor 1 15 of the air conditioner 1 13 according to the control parameters 106.

[0037] The control parameters 106 may either cease operation of the compressor 1 15 for a time period or alternatively limit the maximum power consumption thereof.

[0038] Generally, the control parameters 106 would be configured to limit the maximum power consumption of the compressor 1 15 for the high-power demand category 108 and to cease operation of the compressor 1 15 for a time period for the intermediate and low-power demand categories 108. The time period may be shorter for the low-power demand category as compared to the intermediate-power demand category.

[0039] For example, for the low temperature category 107 (wherein the air conditioner 1 13 is in heating mode), during the start-up cycle 109, the operational controller 104 may be configured to limit the maximum power consumption (i.e., limit the current draw) of the compressor 1 15 for approximately six minutes for the high-power demand category 108. [0040] The operational controller 104 may be configured to cease operation of the compressor 1 15 for approximately four minutes for the intermediate-power demand category 108 and to cease operation of the compressor 115 for approximately five minutes for the low-power demand category 108.

[0041 ] During the subsequent operational cycle 109, these time periods may be increased. Specifically, during the continual operational cycle 109, the operational controller 104 may limit the maximum power consumption of the compressor 1 15 for approximately seven minutes and cease operation of the compressor 115 for approximately five minutes and six minutes for the intermediate and low-power demand categories 108 respectively.

[0042] Following inhibition at step 206, the operational controller 104 may allow the compressor 115 to run for the remainder of the duration of the start-up cycle 109 which, as alluded to above, may be approximately 30 minutes.

[0043] Depending on the power demand category 108, the operational controller 104 may be configured to return the compressor 1 15 to normal operation by limiting the maximum current draw of the compressor 1 15 at step 207. Such control may employ ramp control wherein the maximum current draw is allowed to ramp up.

[0044] The algorithm 200 may then step to the continual operational cycle via branch 208. Each continual operational cycle may further be executed for a time period, such as 30 minutes. As alluded to above, the operational controller 104 may determine the power demand category at step 203 but wherein respective control parameters 106 for the continual cycle 109 would be employed as opposed to those for the start-up cycle 109. As also alluded to above, the control parameters for the continual cycle 109 may inhibit operation of the compressor 115 for greater time periods.

[0045] Should the temperature increase above 15°C, the algorithm 200 may proceed at branch 209 to the high temperature category 107. The control algorithm 200 for the high temperature category 107 would be generally the same as described above although the timing of the control parameters would differ according to the power demand category 108. [0046] For example, during the start-up cycle, for the high-power demand category 108, the operational controller 104 may be configured to limit the maximum current of the compressor for six minutes and cease operation of the compressor 1 15 for four minutes and five minutes for the intermediate and low-power demand categories 108 respectively.

[0047] Thereafter, for the continual operation cycle 109, the timing for the control parameters may also be increased for the high temperature category.

[0048] For example, during the continual operation cycle 109, for the high-power demand category 108, the operational controller 104 may be configured to limit the maximum current of the compressor for nine minutes and cease operation of the compressor 1 15 for seven minutes and eight minutes for the intermediate and low- power demand categories 108 respectively.

[0049] In embodiments, the system 100 may be configurable depending on the control capabilities of the air-conditioner 1 13. For example, the system 100 may comprise two operational control selection switches configurable in a first configuration (such as where both switches are off) for where the controller 101 interfaces an inverter airconditioner 1 13 having full DRED functionality which would be operated according to the aforedescribed functionality.

[0050] The operational control selection switches may be further configurable in a second configuration (such as where one switch is on and one switch is off) for airconditioners 1 13 that do not have full DRED functionality but rather only demand control functionality. The controller 101 may store a second set of control parameters 106 for this second configuration.

[0051 ] The operational control selection switches may be further configurable in third configuration (such as where both switches are on) for certain types of airconditioners 1 13 having a modified form of demand control functionality wherein the air-conditioner 1 13 comprises DIP switch settings for thermal percentage operation modes (as opposed to thermal on or off operation modes). The controller 101 may store a third set of control parameters 106 for this third configuration. [0052] The foregoing description, for purposes of explanation, used specific nomenclature to provide a thorough understanding of the invention. However, it will be apparent to one skilled in the art that specific details are not required in order to practise the invention. Thus, the foregoing descriptions of specific embodiments of the invention are presented for purposes of illustration and description. They are not intended to be exhaustive or to limit the invention to the precise forms disclosed as obviously many modifications and variations are possible in view of the above teachings. The embodiments were chosen and described in order to best explain the principles of the invention and its practical applications, thereby enabling others skilled in the art to best utilize the invention and various embodiments with various modifications as are suited to the particular use contemplated. It is intended that the following claims and their equivalents define the scope of the invention.

Claims

1 . A system for inverter air conditioner power consumption reduction, the system comprising: a controller having: an I/O interface interfacing control terminals of an inverter air conditioner; a processor executing an operational controller; and a memory device storing control parameters in relation to: temperature categories; and power demand categories, wherein the operational controller is configured to: determine a temperature category; determine a power demand category; load control parameters according to the temperature and power demand categories, and to control operation of the air conditioner by controlling the I/O interface to inhibit a compressor of the air conditioner according to the control parameters.

2. The system as claimed in claim 1 , wherein inhibition of the compressor is by way of ceasing operation of the compressor for a time period.

3. The system as claimed in claim 1 , wherein inhibition of the compressor is by way of limiting a maximum current draw of the compressor for a time period.

4. The system as claimed in claim 1 , wherein, following inhibition of the compressor, the operational controller is configured to limit the maximum power draw of the compressor.

5. The system as claimed in claim 4, wherein limiting the maximum power draw comprises ramp control wherein the maximum power draw is gradually increased.

6. The system as claimed in claim 4, wherein the operational controller is configured to limit the maximum power draw of the compressor depending on the power demand category.

7. The system as claimed in claim 6, wherein the power demand category is not a high-power demand category.

8. The system as claimed in claim 1 , wherein the memory device further stores the control parameters in relation to operational cycles and wherein the operational controller is further configured to determine a cycle and to load control parameters further according to the cycle.

9. The system as claimed in claim 8, wherein the cycles comprise a start-up cycle and a continual operational cycle and wherein the operational controller is configured to enter the start-up cycle at start-up and then repeatedly implement the continual operational cycle.

10. The system as claimed in claim 1 , wherein the operational controller is configured to detect operation of the air conditioner.

1 1 . The system as claimed in claim 10, wherein the operational controller is configured to detect operation of the air conditioner by measuring a current draw greater than a threshold for more than a time period.

12. The system as claimed in claim 1 , wherein the I/O interface interfaces a temperature sensor and wherein the operational controller is configured to determine the temperature category according to a temperature reading from the temperature sensor.

13. The system as claimed in claim 1 , wherein the I/O interface interfaces a current sensor facing a power source and the compressor and wherein the operational controller is configured to determine the power demand category according to a current reading from the current sensor.

14. The system as claimed in claim 1 , wherein the temperature category comprises a low temperature category and a high temperature category.

15. The system as claimed in claim 14, wherein the low temperature category is less than approximately 15°.

16. The system as claimed in claim 1 , wherein timing of the control parameters differ according to the temperature category.

17. The system as claimed in claim 16, wherein, during a start-up operational cycle, the timing is the same for the low and high temperature categories.

18. The system as claimed in claim 16, wherein, during a continual operational cycle, the timing is greater for the high temperature category.

19. The system as claimed in claim 1 , wherein the power demand category comprises at least two categories.

20. The system as claimed in claim 19, wherein the at least two categories includes a higher power demand category wherein the compressor draws more than 75% of a maximum current threshold.

21 . The system as claimed in claim 19, wherein the power category comprises an intermediate-power demand category wherein the compressor draws between approximately 50 and 75% of the maximum current threshold.

22. The system as claimed in claim 29, wherein the power category comprises a low-power demand category wherein the compressor draws less than approximately 50% of the maximum current threshold.

23. The system as claimed in claims 20 - 22, wherein the controller is configurable with the maximum current threshold.

24. The system as claimed in claim 1 , wherein timing of the control parameters differ according to the power demand category.

25. The system as claimed in claim 24, wherein the timing is greatest for a high- power demand category.

26. The system as claimed in claim 24, wherein the timing is lowest for an intermediate-power demand category.

27. The system as claimed in claim 1 , wherein timing of the control parameters differ according to the cycle.

28. The system as claimed in claim 27, wherein timing in relation to a continual operational cycle is greater than that for a start-up cycle.

29. The system as claimed in claim 1 , wherein the system is configurable depending on the control capabilities of the air-conditioner.

30. The system as claimed in claim 29, wherein the system is configurable in a first configuration for an inverter air-conditioner having first control functionality and a second configuration for air-conditioners that have second control functionality and wherein the controller uses first and second set of control parameters for the first and second configurations accordingly.

31 . The system as claimed in claim 1 , wherein the control terminals are Demand Response Enabling Device (DRED) control terminals.