Refrigerator with DC board

Abstract

Described is, among other things, a refrigerator (10) comprising a DC power limiter (43). The DC power limiter is configured to only provide power to some DC components at the time based on a priority list of DC powered devices in order not to exceed to power output limitations of a DC power board (50).

Description

[0001] Refrigerator with DC board

[0002] TECHNICAL FIELD

[0003] The present disclosure relates to a refrigerator and the control thereof. In particular the present disclosure relates to a refrigerator comprising a DC power board for powering DC powered devices of the refrigerator.

[0004] BACKGROUND

[0005] Refrigerators are used to keep food and other goods at a cooled temperature inside a cooled compartment of the refrigerator. When the cooled compartment is set to a temperature below the freezing point, the refrigerator can be referred to as a freezer.

[0006] Regardless of the type of refrigerator, modern refrigerators are typically provided with a plurality of electrically powered devices connected to a DC power board that provides a DC power output.

[0007] There is a constant desire to improve refrigerators. Hence, there is a need for an improved refrigerator.

[0008] SUMMARY

[0009] It is an object of the present invention to provide an improved refrigerator.

[0010] This object and / or others are obtained by the refrigerator as set out in the appended claims. As has been realized by the inventors, the configuration of DC powered devices in a refrigerator can vary widely. At the same time the DC power supply, typically implemented as a DC power board, has a maximum DC power output. Further, it is not desirable to overdimension the DC power board due to cost reasons. Also, it is not known today what the configuration will be in future refrigerator models in terms of number of DC powered devices, since there is tendency to convert AC electrical loads into DC ones, that offer typically increased efficiency. So, what potentially can happen is that the maximum power is exceeded in some scenarios. This is not desired since the life time of different components can be reduced and the operation of the refrigerator can become unpredictable since some DC powered devices will not receive a correct power when the maximum power is exceeded. In order to address this problem, a DC power limiter is provided. The DC power limiter is configured to only provide power to some DC components at the same time based on a priority list of DC powered devices.

[0011] In accordance with the invention, a refrigerator is provided. The refrigerator comprises a plurality of DC powered devices, and a controller for controlling DC powered devices of the refrigerator. The refrigerator further comprises a DC power board for providing DC power to the plurality of DC powered devices. In the refrigerator, a DC power limiter is provided. The DC power limiter is configured to obtain a maximum DC power output of the DC power board, obtain a priority list of all DC powered devices or groups thereof and obtain control signals from the controller relating to DC powered devices currently activated. The DC power limiter is further configured to limit provision of DC power via the DC power board to activated DC powered devices to only a subset of the activated DC powered devices based on the priority list at the time such that the output power from the DC power board does not exceed the maximum DC power output of the DC power board. Hereby, the power board can have a cost-efficient configuration and at the same time ensure that the maximum power of the DC power board is not exceeded. The refrigerator can be reconfigured to add new DC power devices without having to upgrade the DC power board. Prioritized DC components will always be possible to be activated. In accordance with one embodiment, the DC powered devices are divided into at least two groups, wherein the at least two groups are mutually prioritized and wherein the DC power limiter is configured to only activate a sub-set of the at least two mutually prioritized groups at the time based on the priority of each of said at least two groups of DC powered devices. Hereby an easy to implement procedure for activating / deactivating DC powered devices can be obtained in that groups of DC powered devices can be prioritized instead of having to provide a prioritization for each single DC powered device.

[0012] In accordance with one embodiment the top prioritized group comprises all DC powered user interface devices. Hereby in is ensured that the functionality interacting with a user is always available when a user interacts with the refrigerator. The DC powered user interface devices can comprise one or many of the following types of devices: compartment lights, indicator LEDs, displays, audio generators and vibration generators.

[0013] In accordance with one embodiment, the DC power limiter is configured to provide DC power to only one group of at least two groups of DC powered devices at the time. Hereby an easy to implement procedure for limiting the DC power supply is obtained that does not require specific knowledge of the DC power consumption of different DC powered devices. The groups of DC powered devices can comprise one or many of valves, baffles, and fans.

[0014] When a fan is provided, the DC power limiter can be configured to accelerate a fan in accordance with a pre-set acceleration scheme. Hereby additional power limitations can be provided. Also, when a plurality of fans is provided in the refrigerator wherein the DC power limiter can be configured to limit power to the plurality of fans individually for each fan. Hereby another power limiting procedure can be achieved.

[0015] In accordance with some embodiments, the power limiter is further configured to obtain door information of door open status for all or some doors of the refrigerator, and to further control the power limitation based on the door information. For example lamps can be switched off when the door is open for more than a pre-set time of priority for different groups can be altered to take into account that the door is open.

[0016] BRIEF DESCRIPTION OF THE DRAWINGS

[0017] The present invention will now be described in more detail by way of non-limiting examples and with reference to the accompanying drawings, in which:

[0018] - Fig. 1 illustrates a refrigerator,

[0019] - Figs. 2a and 2b are flow charts illustrating some steps performed when controlling a refrigerator,

[0020] - Fig. 3 illustrates a controller, and

[0021] - Fig. 4 illustrates a refrigerator in an alternative embodiment.

[0022] DETAILED DESCRIPTION

[0023] In FIG. 1, a schematic view of a typical household refrigerator 10 comprising a cooled compartment 12 is shown. The exemplary refrigerator 10 in Fig. 1 is only shown with a single cooled compartment 12. However, the refrigerator can be any type of refrigerator such as a combined refrigerator / freezer or any other type of refrigerator comprising one or more cooled compartment. The refrigerator 10 is shown in a schematic way and some components are omitted and some components are shown in a simplified manner for better understanding of how the invention can be implemented. To cool the refrigerator a cooling system is provided.

[0024] The cooling system comprises at least one compressor 32, at least one condenser 34 and at least one evaporator 36. The cooling system is controlled by a controller 42 of the refrigerator 10. The cooling system also comprises at least one capillary tube or a similar device such as an expansion valve 38. The cooling system can also comprise other components not shown in Fig. 1. The compressor 32 drives a refrigerant in a cycle whereby the condenser 34 becomes hot and the evaporator 36 becomes cold. Depending on the type of compressor, different control schemes can be applied. The controller 42 can, based on some input signals, determine how the compressor 32 is to be run. The input signal typically comprises a temperature sensor signal from a temperature sensor 44 indicative of the temperature in the refrigerator 10. The controller 42 can additionally be configured to control other components of the refrigerator 10. Such other components can for example be DC powered devices.

[0025] DC power devices can be powered via a DC power board 50 providing a DC power supply to various devices provided in the refrigerator 10. The DC powered devices can be many different types of electrical devices such as lamps, displays, dampers, fans, valves etc. Such DC devices are exemplified in Fig. 1 by a lamp 52 and a valve 53.

[0026] The controller 42 can be configured to control all electrical devices of the refrigerator 10. The control can be executed based on a number of different input signals such as the signal from the temperature sensor, and a door opening sensor. Also, the control can be executed based on user settings such as set temperature for the refrigerator. In case there is a plurality of cooled compartments of the refrigerator such as a combined refrigerator / freezer, temperature sensor signals from a plurality of cooled compartments can be used as input signals and a plurality of user settings can be applied. Also, other user commands can be input that can be used as input signals to the controller 42.

[0027] Based on the input signals, the controller 42 issues command signals to activate / deactivate different electrically powered devices of the refrigerator such as the compressor 32 and the various DC powered devices 52, 53. However, as has been realized, depending on the maximum output power of the DC power board, the maximum requested DC power when activating a set of DC powered devices 52, 53 could potentially exceed the maximum output power of the DC power board in some scenarios. In order to ensure that the maximum power from the DC power board is not exceeded a DC power limiter 43 can be provided.

[0028] The DC power limiter 43 can be implemented as a separate device located between the controller 42 and the DC power board 50 or the DC power limiter 43 can be implemented as an add-on software or hard ware module to the controller 42. The function of the DC power limiter 43 is to obtain a maximum DC power output of the DC power board thereby gaining knowledge of the constraints of the DC power board. The DC power limiter can obtain knowledge about the power constraints of the DC power board in different manners, both directly and indirectly. For example, the knowledge can be directly provided by entering the power constrains s as an input parameter. The maximum power output can also be obtained indirectly by limiting the maximum power output to a power that all potentially used power boards can output. For example, the power limiter can be configured to allow for a maximum pre-set power output where this maximum pre-set power output is known to be available for a selected DC power board.

[0029] The DC power limiter 43 can be further configured to obtain a priority list of all DC powered devices or groups of DC powered devices. For example, the DC powered devices can be divided into groups of different types of components such that one group comprises all lamps another group comprises fans, a third group comprises valves a fourth group baffles etc. When the controller 42 emits control signals such signals relating to DC powered devices currently activated, the DC power limiter 43 can act to not activate some of the DC powered devices. In other words, the DC power limiter can cancel some activation signals to the DC powered devices in order not to exceed the maximum output power from the DC power board 50.

[0030] Thus, the DC power limiter can act to limit provision of DC power via the DC power board 50 to activated DC powered devices 52, 53 to only a subset of the activated DC powered devices based on the priority list at the time, such that the output power from the DC power board 50 does not exceed the maximum DC power output of the DC power board 50.

[0031] In accordance with another embodiment shown in Fig. 4, a power supply 50 is embedded in the controller 42. So, in this case there is one single board hosting both the controller 42 and the DC power supply 50.

[0032] Different control procedures can be applied. In Fig. 2a some steps performed by the controller 42 in accordance with an exemplary control procedure are depicted. The control procedure starts in a step 200. First in a step 201 data relating to the operation of the refrigerator 10 are obtained. In response to the operation data obtained in step 201, the controller 42 generates a set of control signals in a step 203. The control signal can typically comprise activation / deactivation of one or many DC powered devices 52, 53.

[0033] Activation signals to the DC powered devices can be limited (filtered) by the DC power limiter 43. The limitation procedure applied by the DC power limiter 43 can be based on a priority order for the DC powered devices. In accordance with one exemplary embodiment, the DC-load priority follows the following order:

[0034] - Lamps or LEDs associated to door opening for illuminating compartment have the highest priority and can prevent all the other DC powered devices to operate or can change their status.

[0035] - Valves are assigned the second priority and can prevent damper and fans to operate or can change their status,

[0036] - Dampers are assigned the third priority and can prevent fans to operate or can change their status.

[0037] - All the fans can turn-off or decelerate at any time t, even if the valves or the dampers changed position at time t or other fans are switched-on or accelerated at the same time. An exemplary procedure for limiting the activation signals to the DC powered devices are described in conjunction with Fig 2b.

[0038] First in a step 211 it is checked if any DC powered user interface devices are activated. For example, lamps or displays or audio generator. If user interface devices are activated, all or some other DC powered devices belonging to lower priority groups than lamps can be deactivated or power limited by the DC power limiter in a step 212. For example, activation signals to other DC powered devices can be cancelled by overriding the signal from the controller 42. If no DC powered user interface device is activated in step 211, it is checked if any valves are activated in a step 213. If valves are activated, all or some other DC powered devices belonging to lower priority groups than valves can be deactivated or power limited by the DC power limiter in a step 214. If no valve is activated in step 213, it is checked if any dampers are activated in a step 215. If dampers are activated, all or some other DC powered devices belonging to lower priority groups than dampers can be deactivated or power limited by the DC power limiter in a step 216. If no damper is activated in step 215, it is checked if any fans are activated in a step 217. If fans are activated, all or some other DC powered devices belonging to lower priority groups than fans can be deactivated or power limited by the DC power limiter in a step 218. Further, when a fan is activated, the DC power limiter can be configured to accelerate the fan in accordance with a pre-set acceleration scheme. Hereby additional power limitations can be provided in that the fan is not accelerated in full power. Also, when a plurality of fans is provided in the refrigerator, the DC power limiter can be configured to limit power to the plurality of fans individually for each fan. Hereby another power limiting procedure can be achieved.

[0039] The procedure of Fig. 2b is the repeated and when a higher prioritized group of DC powered components is activated, lower prioritized groups of components can be deactivated or power limited. In accordance with some embodiments, if the door is open for more than a preset timeout period (typically a few minutes such as 3 minutes), then the lamps are switched off and the deactivation of other DC powered components can then be removed so that DC powered components such as fans, valves and dampers are not power limited for more than a preset time period.

[0040] In the exemplary procedures above the controller 42 is configured as a single controller. However, the functions of the controller 42 can be distributed to a plurality of control units. Further, the controller 42 can be implemented using suitable hardware and or software. An exemplary controller 42 is depicted in Fig. 3. The hardware can comprise one or many processors 301 that can be arranged to execute software stored in a readable storage media 302. The processor(s) can be implemented by a single dedicated processor, by a single shared processor, or by a plurality of individual processors, some of which may be shared or distributed. Moreover, a processor may include, without limitation, digital signal processor (DSP) hardware, ASIC hardware, read only memory (ROM), random access memory (RAM), and / or other storage media. The processor 42 is adapted to send and receive signals from other entities such as the temperature sensor 44. the compressor 32, a door switch and potentially different external sensors or other units using an interface 303. Further, as is set out above, the DC power limiter 43 can be implemented in various manners. Here an implementation where the DC power limiter is implemented as a software module of the controller 42 is envisaged. However, the DC power limiter can also be implemented in other ways such as a hardware module of the controller 42 or as a separate device. The controller 42 provided with the DC power limiter 43 can in particular be configured to implement the control procedures as described herein.

[0041] By providing a refrigerator as set out herein, a more efficient refrigerator that can handle different configurations of DC powered devices can be obtained. Different types of loads can be considered such as DC variable speed fans, DC stepper valves, DC dampers (also known as motorized baffles), DC lamps or LEDs for illumination, etc. By enabling synchronization of the switch-on, switch-off and potentially also modulation of the various electrical loads of a refrigerator by a prioritized synchronization algorithm implemented by a DC power limiter the overall peak-power constraint of the DC-power supply is never violated. The DC power limiter is advantageously based on a prioritization logic that permits to respect the peak-power constraint while having limited impact on the thermodynamic performance of the refrigerator.

Claims

CLAIMS1. A refrigerator (10) comprising:- a plurality of DC powered devices (52, 53),- a controller (42) for controlling DC powered devices of the refrigerator,- a DC power board (50) for providing DC power to the plurality of DC powered devices,- a DC power limiter (43) configured to:- obtain a maximum DC power output of the DC power board,- obtain a priority list of all DC powered devices or groups thereof,- obtain control signals from the controller (42) relating to DC powered devices currently activated,- limit provision of DC power via the DC power board to activated DC powered devices to only a subset of the activated DC powered devices based on the priority list at the time such that the output power from the DC power board does not exceed the maximum DC power output of the DC power board.

2. The refrigerator according to claim 1, wherein the DC powered devices are divided into at least two groups, wherein the at least two groups are mutually prioritized and wherein the DC power limiter is configured to only activate a sub-set of the at least two mutually prioritized groups at the time based on the priority of each of said at least two groups of DC powered devices.

3. The refrigerator according to claim 2, wherein the top prioritized group comprises all DC powered user interface devices.

4. The refrigerator according to claim 3, the DC powered user interface devices comprise one or many of the following types of devices: lamps, displays, audio generators and vibration generators.

5. The refrigerator according to any one of claims 2 - 4, wherein the DC power limiter is configured to provide DC power to only one group of said at least two groups at the time.

6. The refrigerator according to any one of claims 2 - 5, wherein one group of said at least two groups comprises valves.

7. The refrigerator according to any one of claims 2 - 6, wherein one group of said at least two groups comprises baffles.

8. The refrigerator according to any one of claims 2 - 7, wherein one group of said at least two groups comprises fans.

9. The refrigerator according to claim 8, wherein the DC power limiter is configured to accelerate a fan in accordance with a pre-set acceleration scheme.

10. The refrigerator according to claim 8 or 9, when a plurality of fans is provided in the refrigerator wherein the DC power limiter is configured to limit power to the plurality of fans individually for each fan.

11. The refrigerator according to any one of claims 1 - 10, wherein the power limiter is further configured to obtain door information of door open status for all or some doors of the refrigerator, and to further control the power limitation based on the door information.

12. The refrigerator according to claim 11, wherein the DC power limiter is configured to switch off the lamps when a door is open for more than a pre-set time.

13. The refrigerator according to any of the claims 11-12, wherein the DC power limiter is configured to move a group comprising the DC powered user interface devices from a top to a bottom priority when a door is open for more than a pre-set time.

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