Power Management System

Abstract

An example of an apparatus is provided. The apparatus includes a power supply connected to a power source. The power supply is to receive and distribute total power from the power source. The apparatus further includes a first device for receiving a first portion of the total power from the power supply. The apparatus further includes a second device for receiving a second portion of the total power from the power supply. The sum of the first portion and the second portion is the total power. In addition, the apparatus includes a controller for controlling the second device, wherein the controller is to determine the total power required by the first device and the second device. The controller is to reduce the second portion of the total power and restore the second portion of the total power.

Description

Background Art

[0001] A power supply is used to provide power (such as electrical power) to components of a system (such as a computer system). In particular, a power supply can be used to convert power from a power source (such as an electrical outlet), such as in the form of direct current, to power for a component. Thus, a power supply can be used in a variety of computer systems because a computer system includes several different components.

[0002] The components powered by a power supply may vary during normal operation. For example, an internal hard disk may not draw much power when at rest, but when data is requested, additional power may be used to drive the motor to spin the disk. For this reason, the power supply may also be rated for a maximum power. If a component demands more power than the maximum rating, damage to the power supply due to overheating may occur. BRIEF DESCRIPTION OF THE DRAWINGS

[0003] Reference will now be made, by way of example only, to the accompanying drawings in which:

[0004] Figure 1 is a block diagram of an example apparatus for managing power between multiple devices;

[0005] Figure 2 is a flow chart of an example of a method of managing power among multiple devices;

[0006] Figure 3 is a block diagram of another example apparatus for managing power among multiple devices; and

[0007] Figure 4 is a flow chart of another example of a method of managing power among multiple devices. DETAILED DESCRIPTION

[0008] Power supplies are generally used to provide power to a computer system and peripheral devices of the computer system. For example, each device of a typical computer system may have a separate power supply that plugs into a standard wall power outlet. In particular, a computer processing unit may plug into a wall outlet. A monitor may also plug into a wall outlet. Other peripherals that may have their own power supplies may include additional monitors, printers, scanners, docking stations, and / or external memory storage units.

[0009] In this example, each device may include a separate power supply having a power rating suitable for the device. For example, a computer processing unit may have a power rating of about 100W to support components if each of them draws a large amount of power. Some printers may have a power rating of about 50W to support components because the additional mechanical components of the printer are used to move paper and / or printheads. A display unit may have a power rating of about 70W to support components. Because each device may not be running at peak power consumption most of the time, the actual power required is generally lower than the sum of the power ratings of each device of the computer system. Therefore, using a separate power supply for each device will generally result in a waste of power capacity because each device rarely runs at full capacity. In addition, separate power supplies generally use separate cables, which may cause confusion around the computer system.

[0010] A device is provided for managing power between multiple devices using a single power supply. In particular, the rated power of the power supply in the device is lower than the sum of the peak power requirements of all devices to which the power supply is to supply power. The device further includes a controller that can be used to transmit a control signal or message to one of the devices to which the device supplies power. Therefore, when the total power demand from the power supply approaches an upper threshold, the controller can direct the device to self-limit the power demand. When the total power required by the power supply decreases, the controller can send further control signals to the device to remove any power restrictions. Therefore, by using a single power supply, the average excess capacity can be designed to be less than the case where a separate power supply is used for each device. In particular, the power usage between the average devices provides a more efficient use of the power capacity of the single power supply. In addition, by using a single power supply, the number of cables for powering a computer system can be reduced.

[0011] refer to Figure 1 , an apparatus for managing power between multiple devices is generally shown at 10. The apparatus 10 may include additional components, such as various additional interfaces, indicators and / or displays, to interact with a user or operator of the apparatus. For example, such additional interfaces may provide information about the amount of power supplied to each device or the actions taken by the controller to manage power, as discussed in more detail below. In addition, the apparatus 10 may include a user input device, such as a touch screen or a plurality of buttons, to allow a user to provide input to the controller or override the controller. In this example, the apparatus 10 includes a power supply 15, a first device 20, a second device 25, and a controller 30.

[0012] In this example, the power supply 15 is to be connected to a power source, such as an external wall socket. Thus, the power supply 15 is to receive an amount of power from the power source and then subsequently distribute the power to the first device 20 and the second device 25.

[0013] In this example, the manner in which the power supply 15 distributes the power received from the power source is not particularly limited. For example, the power supply 15 may provide the power used by the electrical load depending on the operating state of each component forming the electrical load. In such an example, if the amount of power requested by the electrical load is higher than the amount of power that the power supply 15 may be able to physically supply, the power supply 15 may be easily damaged. By providing power higher than the intended limit, the power supply 15 may overheat and cause damage to itself and nearby components. For the purpose of discussion, it can be assumed that in this example, the power supply 15 has an operating upper limit of providing 120W.

[0014] In other examples, the power supply 15 may only provide power to a threshold amount. In such examples, the power supply 15 may be protected by a fuse or circuit breaker. Therefore, if the electrical load requests power above the threshold amount, the power supply 15 may be disabled by disconnecting the fuse or circuit breaker to protect itself and components near the power supply 15 from damage. In such examples, the power supply 15 may be reset by the user, such as by replacing a fuse or manually resetting the circuit breaker. In a further example, the power supply 15 may include a system that can reduce or stop the power output from the power supply without disabling the power supply 15. In this example, the power supply 15 may be restarted after a fixed period of time or when the electrical load is reduced.

[0015] The first device 20 is to receive a portion of the power distributed by the power supply 15. The exact amount of power received by the first device 20 is not particularly limited and depends on the operating state of the first device 20. In this example, the first device 20 may be a display system. Therefore, the first device 20 may include a processor for rendering images, a memory storage unit for storing image files and rendered images, a light source, and a modulator for the light source to generate images on the screen. It should be appreciated that each of these components operates using electrical power from the power supply 15. In addition, the amount of power drawn by each of these components will vary depending on the state of the display system as a whole. For example, if it is complex to receive a source file at the first device 20, and a large amount of processing is used to generate a rendered image, the processor may draw a relatively large amount of power. Similarly, if the image changes quickly, the modulator may use a relatively large amount of power. In contrast, if the first device 20 is not receiving data, then in this example, the first device 20 may be in a sleep mode or a screen saver mode and draw a very small amount of power. For the purpose of discussion, it is assumed that if all components are to operate at full capacity, the first device 20 in this example can draw up to about 70W of power. However, the first device 20 rarely operates in this state, and may instead operate by drawing approximately 40 W of combined power during normal use, and approximately 10 W of combined power when idle.

[0016] The second device 25 is to receive another portion of the power distributed by the power supply 15. The exact amount of power received by the second device 25 is not particularly limited and depends on the operating state of the second device 25. In this example, the second device 25 can be a computer module or a desktop unit. Therefore, the second device 25 can include a central processing unit, various communication interfaces such as a graphics interface and / or a network interface, a memory storage unit such as a hard disk drive, a fan unit for cooling various components within the computer module, and other components that can be used during the operation of the computer module. It should be understood that each of these components ultimately uses power from the power supply 15 to operate. In addition, the amount of power drawn by each component will vary depending on the state of the computer module as a whole. For example, if the second device 25 is charging a battery, the charging capacity may be suspended or reduced. In addition, if the second device 25 is performing complex calculations, the central processing unit will draw a large amount of power to perform the calculations. Similarly, if the second device 25 is receiving data from a network via a network interface card, the network interface card can draw a relatively large amount of power when receiving a data packet from the network. In addition, if the memory storage unit may draw a relatively large amount of data when writing a received data packet to the memory. In contrast, if the second device 25 is not being used, then in this example, the second device 25 can enter a sleep mode and draw a very small amount of power. For the purposes of discussion, assume that if all components were to operate at full capacity, the second device 25 in this example could draw up to about 90 W of power. However, the second device 25 rarely operates in this state, but instead can operate by drawing a combined power of about 60 W during normal use and a combined power of about 10 W to 20 W when idle.

[0017] Continuing with this example, the apparatus 10 includes a first device 20 and a second device 25. In this particular example, there are no additional devices. Therefore, it can be assumed that the total power distributed by the power supply 15 is the sum of the power provided to the first device 20 and the second device 25. Therefore, if both the first device 20 and the second device 25 are operating at full capacity, the total electrical power drawn from the power supply 15 will be 160W, which is above the upper limit of operation of the power supply 15. However, if both the first device 20 and the second device 25 are operating at an average state, the total draw of electrical power from the power supply 15 will be approximately 100W, which is within the upper limit of operation of the power supply 15.

[0018] Furthermore, in this example, the second device 25 may be an intelligent device capable of regulating its own power requirements. For example, the second device 25 may be capable of reducing the power consumption of the central processing unit at the expense of reduced processing power. Similarly, the second device 25 may be capable of slowing down the read and write speeds of the memory storage unit or the communication interface. Furthermore, the second device 25 may temporarily shut down unnecessary components, such as a fan unit or processor that is not in use.

[0019] The controller 30 is to control the amount of power drawn by the second device 25. In this example, the controller 30 determines the power drawn by the first device 20 and the second device 25. The manner in which the controller determines the power drawn by the first device 20 and the second device 25 is not particularly limited, and may involve measuring the current provided to each of the first device 20 and the second device 25. Thus, in some examples, the controller 30 may respond to an instantaneous change based on a single measurement.

[0020] In other examples, the controller 30 may take multiple measurements before taking any action to limit the power of the second device 25. Because the power drawn by the first device 20 and the second device 25 may fluctuate over time due to changes in the operating states of the first device 20 and the second device 25, the power drawn by the two devices may be measured over a period of time. Therefore, periodic data points may be measured to determine the average power draw of the first device 20 and the second device 25. For example, in some examples, the average power may be determined over a period of about 60s using a sampling rate of about 300ms. In other examples, the average power drawn by the first device 20 and the second device 25 may be determined over a shorter period of time (such as about 10s), or over a longer period of about 5 minutes or 10 minutes to maintain a longer or larger power spike. In other examples, the sampling rate may also be slower or faster. For example, in some examples, the sampling rate may be about 10ms or 100ms, while in other examples, the sampling rate may be slowed down to every 500ms or 1000ms.

[0021] In the case where the total power required by the first device 20 and the second device 25 is higher than the threshold, the controller 30 is to reduce the amount of power drawn by the second device 25. It should be appreciated that setting the threshold is not limited. For example, the threshold limit may be close to the upper limit of the operation of the power supply 15, or it may be lower to provide a buffer. In other examples, the threshold limit may be greater than the upper limit of the operation of the power supply 15 to allow the device to temporarily operate above the recommended upper limit of the operation. The manner in which the controller 30 reduces the amount of power drawn by the second device 25 is not particularly limited. For example, the controller 30 may transmit a command to the second device 25 via a message to reduce the amount of power drawn by the second device 25. It should be appreciated that in this example, the controller 30 does not limit the amount of power distributed to the second device 25 or cut off the power provided to the second device 25. Instead, the controller 30 provides a command to the second device 25, and the second device 25 is to take local actions and determine how to meet the power restrictions imposed by the controller 30. It should be appreciated that this allows the second device 25 to check the processes allowed within it and determine which components are to be limited in power. Thus, rather than reducing power from the power source 15 to the second device 25 , the second device 25 can determine the most efficient way to achieve the power reduction with minimal impact on processes that may be running.

[0022] The message sent from the controller 30 to the second device 25 may be any type of control signal. For example, the message may be a power data object as defined in the Universal Serial Bus Power Delivery Specification (USB PD Specification). In this example, once the second device 25 receives the power data object, a system management interrupt is generated and handled by the BIOS (Basic Input / Output System) of the second device 25 to control the power to be delivered to various components within the second device 25.

[0023] The amount by which the controller 30 limits the power of the second device 25 is not fixed. In one example, the controller 30 may send a command to the second device 25 to reduce the power demand by a fixed amount. Continuing with the above example of the power supply 15 having an operating upper limit of approximately 120 W, the controller 30 may direct the second device 25 to reduce the power by approximately 10 W. The controller 30 may then repeat the measurement to determine whether the power demand has been sufficiently reduced to below a predetermined threshold.

[0024] In another example, the controller 30 can also measure the power drawn by the first device 20, the second device 25, or both the first device 20 and the second device 25. The manner in which the controller 30 determines the individual power requirements of the first device 20 and the second device 25 can be implemented as described above for measuring the total power. For example, the controller 30 can make a determination on a single measurement, or the controller 30 can make multiple measurements over a period of time and use the average power requirements of the first device 20 and / or the second device 25.

[0025] In this example, once the power demand of the second device 25 is determined, the controller 30 can determine the amount by which the total power drawn by both the first device 20 and the second device 25 exceeds the upper threshold of the power source 15. The controller 30 can then direct the second device 25 to reduce the power drawn by the amount determined to be above the upper threshold. In other examples, the controller 30 can also control the first device 20 and divide the power reduction between the first device 20 and the second device 25 via commands to the two devices.

[0026] In the case where the total power required by the first device 20 and the second device 25 is lower than another threshold, the controller 30 will reduce or remove the restriction on the amount of power to be drawn by the second device 25. It should be appreciated that there is no restriction on setting the threshold. In particular, the threshold can be set to be lower than the upper threshold described above. For example, the lower threshold may be approximately 10W less than the upper threshold. In other examples, the lower threshold may be set to be closer to the upper threshold, such as approximately 5W or less lower than the upper threshold. Further examples can be seen that the lower threshold is set to be approximately 15W or more lower than the upper threshold. By setting the lower threshold to be less than the upper threshold, the power consumption fluctuations of the first device 20 and the second device 25 will not cause the controller 30 to continuously switch between reducing the amount of power drawn by the second device 25 and restoring the amount of power drawn by the second device 25.

[0027] The amount by which the controller 30 reduces the limit set on the second device 25 to restore the second device 25 to freely draw power from the power source 15 is not fixed. In one example, the controller 30 may send a command (such as a power data object) to the second device 25 to remove all limits on power demand so that the second device 25 can draw the power to be used based on the operating state of the second device 25. In another example, the controller 30 may send a command (such as a power data object) to the second device 25 to reduce the limit on power demand by a fixed amount. Assuming that the second device 25 operates under the limit that its power draw is to be 60W, and the power drawn by the first device 20 and the second device 25 reaches a combined threshold of 110W, the controller may restore the power draw of the second device 25 to 70W. The controller 30 may then repeat the measurement to determine whether the power demand is still below the predetermined lower threshold.

[0028] In another example, the controller 30 may also measure the power drawn by the first device 20 and the second device 25. Once the total power demand of the first device 20 and the second device 25 is determined, the controller 30 may determine the amount of power that may be lifted from the reduction limit set on the first device 20 and / or the second device 25. The controller 30 may then direct the second device 25 to restore the power drawn by the amount determined to be below the lower threshold limit. It should be appreciated that once the limit on the power drawn by the second device 25 is approximately zero, all limits will have been effectively removed, and the power draw of the second device 25 is restored back to being unlimited. In the event that a limit has not been set on the first device 20 or the second device 25, the total power drawn by both the first device 20 and the second device 25 may continue without limit until the total power exceeds the upper threshold limit of the power source 15.

[0029] In other examples, the controller 30 can also limit the power draw of the first device 20. In these examples, the controller can divide the power recovery between the first device 20 and the second device 25 via commands to the two devices.

[0030] refer to Figure 2 , a flow chart of a method of operating an apparatus to manage power between multiple devices is shown at 200. To help explain the method 200, it will be assumed that the method 200 can be performed with the apparatus 10. In fact, the method 200 can be a way in which the apparatus 10 can be operated. In addition, the following discussion of the method 200 can lead to a further understanding of the apparatus 10 and its various components. It should be emphasized that the method 200 does not need to be performed in the exact order as shown, and the various blocks can be performed in parallel rather than sequentially, or in a different order altogether.

[0031] Beginning at block 210, the power supply 15 receives electrical power from an external power source. The received power is the total amount of power supplied to the device 10. It should be appreciated that the exact amount of power received at the power supply 15 is generally not constant. Instead, the amount of power received at the power supply 15 depends on the electrical load of the first device 20, the second device 25, and the controller 30. Therefore, the sum of the power requirements from all parts of the device 10 determines the total power to be received from the external power source.

[0032] In this example, the power supply 15 can be protected by a fuse or circuit breaker to protect the power supply 15 from drawing too much power from the external power source. Therefore, if the electrical load requests power above the upper power threshold, the power supply 15 can be disabled by disconnecting the fuse or circuit breaker to protect from damage.

[0033] In block 220, the power supply 15 provides a portion of the total power to the first device 20. The proportion of the total power that forms the first power is determined by the electrical load or demand of the first device 20 relative to other devices being powered by the power supply 15. The power drawn by the first device 20 is a portion of the total power drawn from the external power source by the power supply 15. Because the power supply 15 does not operate above an upper power threshold due to a safety mechanism in this example, the first device 20 is to draw an amount of power that is less than the upper power threshold of the power supply 15.

[0034] In this example, the controller 30 can be used to measure the amount of power drawn by the first device 20. In this example, the controller 30 can take multiple measurements to determine the average power draw of the first device 20 over a period of time. Because the power drawn by the first device 20 may fluctuate over time due to changes in the operating state of the first device 20, the drawn power can be averaged to avoid reducing the impact of temporary spikes or troughs in power demand. Therefore, periodic data points can be measured to determine the average power draw of the first device 20.

[0035] In block 230, the power supply 15 provides a portion of the total power to the second device 25. The proportion of the total power that forms the second power is determined by the electrical load or demand of the second device 25 relative to the other devices being powered by the power supply 15. The power drawn by the second device 25 is a portion of the total power drawn by the power supply 15 from the external power source. Because the power supply 15 does not operate above the upper power threshold due to a safety mechanism in this example, the second device 25 draws an amount of power that is less than the upper power threshold of the power supply 15. However, under some operating conditions, the sum of the power drawn at block 220 and the power drawn at block 230 may exceed the upper power threshold, as discussed below.

[0036] In this example, the second device 25 can be used to measure the amount of power drawn by the second device 25. In this example, the controller 30 can make multiple measurements to determine the average power draw of the second device 25 over a period of time. Because the power drawn by the second device 25 may fluctuate over time due to changes in the operating state of the second device 25, the drawn power can be averaged to reduce the impact of temporary spikes or troughs in power demand. Therefore, periodic data points can be measured to determine the average power draw of the second device 25.

[0037] Next, block 240 involves calculating an average power sum that approximates the total power drawn from the power source 15. In this example, the average power sum is obtained by adding the average power drawn by the first device 20 and the second device 25.

[0038] Box 250 includes determining whether the average power and calculated at box 240 are greater than the upper power threshold of the power supply 15. In the event that the average power and are higher than the upper power threshold, the method 200 proceeds to box 260. In box 260, the controller 30 is to transmit a restriction message to the second device 25. In this example, the restriction message is to guide the second device 25 to set a limit on the power consumption of its components. The way in which the second device 25 limits its power can involve checking the process running therein and determining which components are to be limited in power. Therefore, the second device 25 can determine the most effective way to achieve power reduction, while having the least impact on the process that may be running, rather than reducing the power from the power supply 15 to the second device 25 as a whole.

[0039] In some examples, the controller 30 may further determine the average power and the amount above the upper power threshold. In such examples, the limit message provided by the controller 30 may also include the average power and the amount above the upper power threshold. The second device 25 may then be instructed to reduce power consumption by this amount or a slightly larger amount to avoid triggering another limit message due to a smaller power fluctuation.

[0040] In the event that the average power and is not higher than the upper power threshold, the method 200 proceeds to box 270. Box 270 includes determining whether the average power and calculated at box 240 are lower than the lower power threshold. In the event that the average power and is lower than the lower power threshold, the method 200 proceeds to box 280. In box 280, the controller 30 is to transmit a recovery message to the second device 25. In this example, the recovery message is to guide the second device 25 to remove or reduce the restrictions on the power consumption of its components. The way in which the second device 25 removes the restrictions on its power can completely remove all restrictions. In another example, the restrictions on power consumption at the second device 25 can be gradually relaxed until they are completely removed. It should be appreciated that in some iterations of the method 200, the second device 25 may not be limited by the amount of power it may consume. Therefore, if the method reaches box 280, then the second device 25 does not take action when receiving the recovery message. In the event that the average power and is not lower than the lower power threshold, the method 200 simply ends because no action is taken to manage the power supply 15.

[0041] refer to Figure 3 , another example of an apparatus for managing power between multiple devices is shown at 10a. Similar components of the apparatus 10a have similar references to their counterparts in the apparatus 10, except followed by the suffix "a". The apparatus 10a includes a power supply 15a, a first device 20a, a second device 25a, a controller 30a, and a memory storage unit 35a.

[0042] In this example, the first device 20a includes a power supply 15a, a controller 30a, and a memory storage unit 35a. Therefore, the first device 20a can be a display system that can be inserted into a power source such as a wall socket. The first device 20a can then have an additional device, such as a second device 25a, or other peripheral components connected to it via a connector. The connector is not particularly limited, and can be any connector that can provide data connection and provide power to additional devices such as the second device 25a or other peripheral components from the first device 20a. In this example, the connector is a USB-C interface that can provide power from the power supply 15a in the first device 20a to the second device 25a. In addition, the USB-C interface can also transmit messages to the second device 25a in the form of a power data object, such as the restriction message and the recovery message discussed above.

[0043] The apparatus 10a further includes a memory storage unit 35a within the first device 20a. The memory storage unit 35a is to store data received, generated and used by the first device 20a. The manner in which the memory storage unit 35a stores data is not particularly limited. In this example, the memory storage unit 35a may include a non-temporary machine-readable storage medium, which may be, for example, an electronic, magnetic, optical or other physical storage device. In addition, the memory storage unit 35a may store an operating system executable by the first device 20a to provide general functions. Continuing with this example in which the first device 20a is a display system, the operating system may provide various components with the function of rendering data. Examples of operating systems include Android™, Linux™, Unix™, macOS™, iOS™ and Windows™. The memory storage unit 35a may additionally store instructions to operate a processor (not shown) within the first device 20a to implement the various functions and method 200 described above.

[0044] refer to Figure 4 , a flow chart of another example method of operating an apparatus to manage power between multiple devices is generally shown at 200a. Similar blocks of method 200a have similar references to their corresponding components in method 200, except that they are followed by the suffix "a". To help explain method 200a, it will be assumed that method 200a can be implemented with apparatus 10a. In fact, method 200a can be another way that apparatus 10a can be configured. In addition, the following discussion of method 200a can lead to a further understanding of apparatus 10a and the various ways in which apparatus 10a can be configured. It should be appreciated that method 200a can also be applied to apparatus 10.

[0045] Beginning at block 210a, the power supply 15a receives electrical power from an external power source. In this example, the power supply 15 has an upper operating limit and is protected by a fuse or circuit breaker to prevent the power supply 15a from drawing too much power from the external power source.

[0046] In block 220a, the power supply 15a provides a first portion of the total power to the first device 20a. In this example, the first portion of the total power is to be distributed directly by the power supply 15a to the components of the first device 20a. Similarly, in block 230a, the power supply 15a provides a second portion of the total power to the second device 25a. Because the second device 25a is separated from the first device 20a, the power is transmitted to the second device 25a via a connector (such as a USB-C interface).

[0047] In this example, the controller 30a measures the amount of power drawn by the first device 20a and the second device 25a. In this example, the controller 30a may take multiple measurements to determine the average power draw of the first device 20a and the second device 25a over a period of time.

[0048] Next, block 240a involves calculating an average power sum, which involves adding the powers measured during the execution of blocks 220a and 230a.

[0049] Frame 250a comprises determining whether the average power sum calculated at frame 240a is greater than the upper power threshold of power supply 15a. The upper power threshold can be set relative to the upper limit of operation, such as 10W below the operation limit. In the event that the average power sum is above the upper power threshold, method 200a proceeds to frame 260a to transmit a restriction message to second device 25a. In this example, the restriction message is a command to guide second device 25a to limit the power demand of its components.

[0050] In the event that the average power and is not higher than the upper power threshold, the method 200a proceeds to frame 270a. Frame 270a includes determining whether the average power and calculated at frame 240a are lower than the lower power threshold. In the event that the average power and are lower than the lower power threshold, the method 200a proceeds to frame 280a. In frame 280a, the controller 30a will transmit a recovery message to the second device 25a. In this example, if there is a restriction, the recovery message is a command to guide the second device 25a to reduce the restriction of its components to the power demand.

[0051] In the event that the average power is not below the lower power threshold, the method 200a loops back to block 210a. It should be appreciated that the method 200a is an iterative loop that continues to repeat. In some examples, a delay may be added so that the loop is performed less frequently to reduce the demand on the resources of the controller 30a.

[0052] It should be appreciated that the features and aspects of the various examples provided above may be combined into further examples that also fall within the scope of the present disclosure.

Claims

1. A device comprising: a power supply connected to the power source, the power supply being configured to receive and distribute the total power from the power source; a first device for receiving a first portion of the total power from a power source; a second device for receiving a second portion of the total power from the power source, wherein a sum of the first portion and the second portion is the total power; as well as A controller for controlling a second device, wherein the controller determines the total power required by the first device and the second device based on calculating the average total power by measuring the total power over a time period, if the total power is above an upper threshold, the controller is used to reduce the second part of the total power, and if the total power is below a lower threshold, the controller is used to restore the second part of the total power.

2. The apparatus of claim 1, wherein the controller is to determine a second portion of the total power during the time period.

3. The apparatus of claim 2, wherein the controller determines an amount by which the total power exceeds an upper threshold.

4. The apparatus of claim 3, wherein the controller is to reduce the second portion by the amount.

5. The apparatus of claim 4, wherein the power supply and the controller are disposed within a first device.

6. The apparatus of claim 5, wherein the second device is to be connected to the first device via a USB-C interface, wherein the message from the controller and the second portion of the total power are to be transmitted via the USB-C interface.

7. A method comprising: receiving a total power at a power supply connected to an external power source, wherein the power supply has an upper power threshold; Providing a first power to a first device, wherein a first average value of the first power in a time period is less than an upper power threshold; Providing a second power to a second device, wherein a second average value of the second power in the time period is less than an upper power threshold; Calculate the average power sum of the first average value and the second average value; If the average power sum is above the upper power threshold, transmitting a limit message to the second device, the limit message being used to set a limit on power consumption from the second device; and If the average power sum is below the lower power threshold, a recovery message is transmitted to the second device, the recovery message being used to remove the restriction on the power consumption at the second device.

8. The method of claim 7, further comprising determining an average power and an amount by which an upper power threshold is exceeded.

9. The method of claim 8, wherein the limit message is to instruct the second device to reduce power consumption by the amount.

10. The method of claim 9, wherein the transmission restriction message sends the restriction message via a USB-C interface.

11. The method of claim 10, wherein providing the second power to the second device is performed via a USB-C interface.

12. A non-transitory machine-readable storage medium encoded with instructions executable by a processor, the instructions, when executed by the processor, performing the steps of the method according to any one of claims 7-11.

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