Abstract: An uninterruptible power supply system (UPS) includes an interconnect circuit configured to receive three-phase AC input power from an AC power source and a plurality of UPS subsystems each coupled to the interconnect circuit. A first UPS subsystem includes first and second single-phase AC-to-DC converters. At least one second UPS subsystem includes third and fourth single-phase AC-to-DC converters. In a first mode of operation, the interconnect circuit is configured to conduct at least one phase of the AC input power to the first UPS subsystem and at least one phase of the AC input power to the second UPS subsystem, and, in a second mode of operation, to disconnect the AC input power from the first UPS subsystem and to conduct at least one phase of the AC input power to the second UPS subsystem.

Abstract: According to one aspect, embodiments of the invention provide a method of operating a UPS system having a plurality of UPS's, the method comprising powering on the UPS system, assigning each one of the plurality of UPS's a unique identifier, calculating a master priority index for each one of the plurality of UPS's based on the unique identifier of each one of the plurality of UPS's, and based on the master priority index of each one of the plurality of UPS's, configuring each one of the plurality of UPS's to operate in one of a master mode of operation and a controlled mode of operation.

Abstract: A method for managing a number of power supply units (PSUs) of a power supply device is provided. A total operation time of each PSU is counted. A number of the PSUs to be assigned to work is determined according to a load value of a load connected to the power supply device. Which of the PSUs will be assigned to work and which of the PSUs will be assigned to idle are determined according to the total operation time of each PSU and the determined number of the PSUs to be assigned to work. The PSUs to be assigned to work are controlled to enter a work state, and the PSUs to be assigned to idle are controlled to enter a standby mode.

Abstract: A more efficient power supply unit and a method for supplying power using same are disclosed. The power supply unit comprises a relay for switching alternating current power supplied from a plurality of sources; a direct current power supply for converting the switched current power to direct current power; and a controller for generating a switch signal to control the relay to switch the sources on the basis of the result for monitoring the alternating current power supplied from the sources.

Abstract: A system includes a primary source of power, a main battery, a reserve battery, and a battery management system. A method for operating the system is also disclosed. The main battery of the system is electrically connected to the article, and the reserve battery is configured to back-up the main battery. The battery management system is electrically connected to the main battery. The battery management system maintains the reserve battery in a dormant state when the primary source of power is operational. The reserve battery is also maintained at a dormant state when the primary source of power is not operational; and the main battery is discharging and able to effectively back-up the primary source of power in supplying power to the article.

Abstract: Disclosed are various embodiments for a busbar connection assembly that may be used in, for example, a datacenter. The busbar connection assembly may have multiple conductive plates that are configured to insert between busbar plates of a power bus for the datacenter. The busbar connection assembly may further include multiple slots that are configured to receive the busbar plates of the power bus for the datacenter. The busbar connection assembly may serve as an electrical connection for various purposes.

Abstract: Systems and methods for supplying power to a load include a static switch between a primary power source and a power conditioner associated with a secondary power source, and maintenance switches between the primary and secondary power sources and a load. A controller is operable to actuate the switches. The static switch is operable to conduct power from the primary power source to a capacitor associated with the power conditioner. Current supplied from the primary power source includes portions at a fundamental frequency and a harmonic frequency. The secondary power source or the capacitor, or both, can be used to supply reactive power having a current equal and opposite that of the harmonic portion such that substantially all of the current provided to the load by the primary power source is at the fundamental frequency.

Abstract: A grid-connected power storage system for coupling a power generation system to a grid, including: a main battery for discharging stored power to the load system; at least one additional battery coupled to the main battery for discharging stored power to the load system; a bidirectional converter coupled to the main and additional batteries, and including a plurality of switches for performing a conversion between a DC link voltage, between the power generation system and the grid, and a battery voltage, a first switch of the plurality of switches corresponding to the main battery and a second switch of the plurality of switches corresponding to the additional battery, wherein the first and second switches are connected to each other in parallel; and an integrated controller for selectively controlling operations of the first switch and the second switch based on an amount of power used by the load system.

Abstract: Aspects of the present disclosure involve systems, methods, and the like, for an energy interface system for interfacing alternative energy sources with a utility power source on a premises. The energy interface system provides flexibility in the use and distribution of utility energy sources and alternative energy sources based on several measurements and criteria of the interface system. For example, the energy interface system may allow for the energy consumption to adapt to changing parameters, such as utility rate schedules, cost of alternative fuels and utility premiums for consumption or generation of energy at particular times. The energy interface system also allows for deferment of charging or other high-energy loads to be recognized by the system at otherwise low-energy times. In addition, the energy interface system allows for monitoring and communication with the system for ease of configuring the system based on one or more criteria or measurements.

Abstract: A power supply device (10) includes a plurality of constant current output circuits (14) that can supply power to a load (12). The constant current output circuit (14) includes a pulse generation unit (20) that generates a pulse voltage, and a communication unit (34) that transmits and receives drive information, between the constant current output circuit (14) and the other constant current output circuit (14). When an abnormality occurs in the constant current output circuit (14) supplying power to the load (12) and the constant current output circuit (14) supplying power to the load (12) is switched to the other constant current output circuit (14), the other constant current output circuit (14) drives the pulse generation unit (20) by using the drive information that has been received through the communication unit (34) from the power supply means having supplied power to the load.

Abstract: An uninterruptible power supply includes a first input to receive input power from an input power source, an output to provide output power, a switch, a first logic power supply coupled to the switch, a back-up power source, a charger, a main logic power supply and power converter circuitry. The switch is configured to close when a characteristic of the input power is within a selected range. The first logic power supply is coupled to the switch and configured to receive input power from the input power source when the switch is closed. The first logic power supply has a first DC output. The back-up power source has a second DC output and is coupled to the first DC output at a common node. The charger has a third DC output and is coupled to the common node. The main logic power supply is coupled to the common node and is configured to receive at least one of the first DC output, the second DC output and the third DC output.

Abstract: An electric power system includes: an uninterruptible power supply including an AC switch provided between a commercial power supply and an output part, a secondary battery, and an inverter provided between the AC switch and secondary battery; an important load connected to the output part; a distributed power supply connected to the output part; total load power consumption detection section detecting the power consumption of all loads including the important load; charge/discharge power detection section detecting charge/discharge power of the secondary battery; output power detection section detecting the output power of the distributed power supply; important load power consumption detection section detecting the power consumption of the important load; and a controller that inputs thereto detection values from the total load power consumption detection section, charge/discharge detection section, output power detection section, and important load power consumption detection section and outputs a control

Abstract: A system includes a solar power subsystem that receives power from one or more solar power arrays. A storage control subsystem is coupled to the solar power subsystem to charge a battery from the power received by the solar power subsystem. A grid power control subsystem having an AC to DC converter receives power from a power grid and provides DC voltage to the storage control subsystem. A balance of system control system controls the amount of power received from the power grid as a function of a load, battery charge and received power by the solar power subsystem. The solar array and battery may be sized to provide sufficient power under normal operating conditions, with power being drawn from the grid during abnormal operation conditions.

Abstract: A continuous power supply system suitable for input connection to N continuous power supply networks that are distinct and connected to a single ground potential, where N is an integer greater than or equal to 2. Said continuous power supply system comprises means for switching/selecting one of the power supply networks, means for regulating an output voltage established by the power supply system, and a control unit for the means for switching/selecting and for the means for regulating. The means for regulating the output voltage includes N distinct buck-boost converters with shared inductance. A given buck-boost converter is dedicated to each power supply network for regulating the voltage output of the power supply system on the basis of an input voltage established by the corresponding power supply network.

Abstract: An arrangement for a switching function unit for Ethernet having a number of active components of the Ethernet which are combined by a switching function unit to form a functional unit; and at least three mutually independent power supplies for supplying power to the active components, wherein a first of the at least three power supplies is a local power supply for the switching function unit, a second of the at least three power supplies is a first extraneous power supply via Ethernet for the switching function unit, and a third of the at least three power supplies is a second extraneous power supply via Ethernet for the switching function unit.

Abstract: A portable power supplying system includes an enclosure including at least one wheel mounted to a bottom portion of the enclosure, a battery secured within the enclosure, and a battery charger secured within the enclosure. The battery charger is electrically connected to the battery for charging the battery. The system further includes a DC/AC inverter secured within the enclosure. The DC/AC inverter is electrically connected to the battery, and is configured to convert a direct current supplied by the battery to an alternating current. The system further includes a power outlet including at least one female household electrical connection, and a transfer switch secured within the enclosure. The transfer switch is electrically connected to the DC/AC inverter, the battery charger, the power outlet and a power source input.

Abstract: To provide an electric power system capable of adequately controlling the power flow in an AC switch (120) constituting an interruptible power supply, an electric power system according to the present invention includes: an uninterruptible power supply (100) including an AC switch (120) provided between a commercial power supply (200) and an output part (102), a secondary battery (130), and an inverter (135) provided between the AC switch (120) and secondary battery (130); an important load (150) connected to the output part (102); a photovoltaic power supply (140) connected to the output part (102); an electric power detection section (181) that detects the power consumption of all loads including the important load (150); an electric power detection section (131) that detects charge/discharge power of the secondary battery (130); and a controller (110) that inputs thereto detection values from the electric power detection section (181) and electric power detection section (131) and outputs a control command

Abstract: Systems and methods for restoring service within electrical power systems are disclosed. The methods may include identifying a restoration path for an outage area within a power system, selecting a mobile energy resource connection site that is electrically connected to at least one of the restoration path and the outage area, sending power injection requests to a plurality of mobile energy resources, at least some of which may be proximate the connection site, receiving power injection acceptances from participating ones of the plurality of mobile energy resources, and implementing the restoration path. The systems may include a processor and a computer readable storage medium having a plurality of machine-readable instructions embodied thereon and con figured for execution by the processor to carryout the method.

Abstract: An apparatus comprises a transformer coupled to a mains power, a backup power source comprising a first battery, a first power supply line switch configured to switch the power source between the backup power source and the mains power, a connecting interface coupling the power source to an external electronic device comprising a second battery which is rechargeable and a second power supply line switch which is configured such that the external electronic device is able to be powered by either the power source or a second battery, and a charging detector configured to detect the availability of the mains power, wherein the first power supply line switch is further configured to couple the backup power source to the external electronic device via the connecting interface when the mains power is not available such that the first battery is able to deliver power to the external electronic device.

Abstract: A method, computer-readable medium, system, and apparatus for improving energy transfer with a vehicle are disclosed.

Abstract: This document discusses, among other things, systems and methods to provide an internal supply rail with over voltage protection using a host power source, an external power source, and a switch configured to receive indications of host and external power source validity. In an example, the switch can be configured to provide the internal supply rail using the host power source when the indication of host power source validity indicates a valid host power source and the external power source when the indication of host power source validity indicates an invalid host power source and the indication of external power source validity indicates a valid external power source.

Abstract: An energy storage device for a power compensator including a battery stack including a plurality of battery units connected in series, each of the battery units including one or more parallel-connected battery modules including a plurality of battery cells, where each battery unit further includes a bypass switch connected in parallel with the battery modules and the energy storage device comprises a control unit which is operatively connected to the bypass switches and adapted to receive information on a failure in any of the battery modules and to close the bypass switch in order to bypass the battery unit in case of a failure in any of the battery modules of the battery unit.

Abstract: A power supply system including: a power storage device which is connected to a system power supply and is chargeable and dischargeable; a second load which is connected in parallel to the power storage device; a power generation device which is connected to the second load, generates power, supplies the generated power to the second load, and performs a shutdown process for stopping power generation using power supplied from the power storage device; and a determination device which determines whether or not a remaining amount of power in the power storage device is greater than a shutdown power amount which is an amount of power necessary for the power generation device to perform the shutdown process, in which the power generation device performs, while in operation, the shutdown process or supplying of power to the power storage device according to the determination by the determination device.

Abstract: A power supply apparatus is disclosed. The power supply apparatus includes a rechargeable battery and a battery management system (BMS) for managing charging and discharging of the battery. The power supply apparatus is configured to supply an operating power to the BMS from an external power of an external power source when the external power source is in a normal state and is capable of supplying the external power to a load through the power supply apparatus. The power supply apparatus is further configured to supply the operating power to the BMS from electric energy stored in the battery when the external power source is in a state different from the normal state and not capable of supplying the external power to the load through the power supply apparatus.

Abstract: A power storage system and method of controlling the system is disclosed. The power storage system is connected to a power generation system and a grid. If a remaining amount of power of a battery is insufficient when the grid is in a quasi-normal state, the battery is charged by directly receiving electric power from the grid, and thus electric power is available for the if the grid subsequently goes back into the abnormal state.

Abstract: Computational enclosures may be designed to distribute power from power supplies to load units (e.g., processors, storage devices, or network routers). The architecture may affect the efficiency, cost, modularity, accessibility, and space utilization of the components within the enclosure. Presented herein are power distribution architectures involving a distribution board oriented along a first (e.g., vertical) axis within the enclosure, comprising a power interconnect configured to distribute power among a set of load boards oriented along a second (e.g., lateral) axis and respectively connecting with a set of load units oriented along a third (e.g., sagittal) axis, and a set of power supplies also oriented along the third axis. This orientation may compactly and proximately position the loads near the power supplies in the distribution system, and result in a comparatively low local current that enables the use of printed circuit boards for the distribution board and load boards.

Abstract: An uninterruptible power supply configured to automatically detect a load level and automatically power off and disable power supply or automatically power on and enable the power supply based on a detected load level, so that energy of a backup source of the uninterruptible power supply is not wasted and a life-cycle of the uninterruptible power supply is extended.

Abstract: This document discusses, among other things, systems and methods to provide an internal supply rail with over voltage protection using a host power source, an external power source, and a switch configured to receive indications of host and external power source validity. In an example, the switch can be configured to provide the internal supply rail using the host power source when the indication of host power source validity indicates a valid host power source and the external power source when the indication of host power source validity indicates an invalid host power source and the indication of external power source validity indicates a valid external power source.

Abstract: Presented is a system and method for providing reconfigurable AC interfaces for AC power systems. The method comprises embedding a reconfigurable AC interface for transferring power between power sources and loads, monitoring the voltage and current of the interfaces of the reconfigurable AC interface, and switching between power sources based on the monitoring. The system comprises a reconfigurable AC interface further comprising an inverter for converting DC power to AC, transfer switches with interfaces for connecting to the inverter, other transfer switches, and AC busses, and a controller that dynamically configures the transfer switches to transfer power between the inverter, and AC busses.

Abstract: A plurality of generators can be connected in parallel to a common electrical bus. Each generator has a controller that regulates the voltage and frequency of the electricity being produced. Before a given generator connects to the electrical bus, its controller senses whether electricity is present on the bus and if not, the connection is made. Otherwise, the controller synchronizes the electricity being produced to the electricity is present on the bus before the connection occurs. The controller in each generator may also implement a load sharing function which ensures that the plurality of generators equitably share in providing the total amount of power demanded by the loads. The load sharing can be accomplished by controlling the generators to operate a substantially identical percentages of their individual maximum power generation capacity.

Abstract: A bulk power assembly includes a bulk power distribution (BPD) subassembly and a bulk power controller and hub (BPCH) subassembly coupled to the BPD subassembly. The BPD assembly is configured to provide bulk DC power from both AC input power and DC input power. The BPD subassembly is configured to distribute the DC bulk power. The BPCH subassembly is configured to monitor and control the BPD assembly.

Abstract: A multiple UPS system includes a plurality of multi-module UPS subsystems coupled to a power tie cabinet, each multi-module UPS subsystem having a plurality of UPS modules. The power tie cabinet includes one or more controllers, collectively referred to as PTC (power tie cabinet) controls. The PTC controls periodically determine a power error message for each of the multi-module UPS subsystems and pass it to the respective multi-module UPS subsystem. A controller of the multi-module UPS subsystem uses the power error message to determine error data that is provided to a power average control loop used in control of power sharing among the UPS modules of the multi-module UPS subsystem.

Abstract: The invention discloses a computer and an expandable power supply system. The expandable power supply system includes N interface units, a determination unit, and a voltage converting unit. N is an integer equal to or more than two. The interface units are electrically connected with at least one power supplies and switching the levels of (N?1) control signals according to conductance of the power supplies. When the interface units are electrically connected with 1st to Mth power supplies, the determination unit outputs a start signal when the determination unit receives power reply signals provided by the 1st to Mth power supplies. M is an integer, and 1?M?N. The voltage converting unit is enabled according to the start signal to distribute operation voltages provided by the 1st to Mth power supplies by utilizing the control signals to generate a supply voltage.

Abstract: A method and system for limiting energy to a sensor and/or an environment in which the sensor is located. A high current sensor driver is powered through a resistance-capacitance (RC) circuit. In a failure mode, the RC circuit constrains output of a sensor driver to the sensor in order to limit average current applied to the sensor. In one embodiment, the capacitor is chosen so that it can provide adequate current to the sensor driver for a short period of time. The value of the resistor may be chosen to ensure that under short circuit conditions direct current (DC) is limited to a safe value. The combined values of the resistor and capacitor may be adjusted such that the capacitor can charge to a prescribed level during the interval between active pulses.

Abstract: A system, apparatus, method, and manufacture for generating backup power in a wireless communications system such as a wireless communications service base station. The system includes a communications interface, a primary power interface, a generator, rectifiers, and a battery circuit. During normal operation, the communications interface is powered from the primary power interface. During a power outage, the communications interface is powered from either the generator or the battery circuit. The generator is cycled on and off during power outages to charge the battery circuit while conserving fuel. To decrease rectification loss, rectifiers are run near full load while rectifying the generator output.

Abstract: Some embodiments include an electrical system. In many embodiments, the electrical system can comprise a system input configured to receive a first power signal from an external power source. In the same or different embodiments, the first power signal can comprise a first voltage. In the same or different embodiments, the electrical system can comprise a system output electrically coupled to the system input. In the same or different embodiments, the electrical system can comprise a charger module electrically coupled to the system input. In the same or different embodiments, the electrical system can comprise a resistive component coupled between the system input and the system output. In the same or different embodiments, the electrical system can comprise a power storage device electrically coupled to the system output and to the charger module.

Abstract: Disclosed is an uninterrupted power supply apparatus, comprising a rectifying unit outputs a positive half-cycle of voltage potential and a negative half-cycle of voltage potential; a backup battery outputs a backup voltage; a first boost unit receives the positive half-cycle of voltage potential or the backup voltage and outputs a first voltage; a second boost unit receives the negative half-cycle of voltage potential or the backup voltage and outputs a second voltage; a current shunt unit receives the first voltage and the second voltage and outputs an AC output voltage; a charge circuit, coupled to the rectifying unit, the backup battery, and the first and/or the second boost unit, for being capable of controlling the first and/or the second boost unit to either store a charging power or charge the backup battery by applying the stored charging power alternatively and successively.

Abstract: An uninterruptible power supply includes an AC-to-DC converting circuit, an energy storage unit, a first path-switching circuit, a second path-switching circuit, an integrated charge/discharge circuit and an operating control unit. If the input voltage is abnormal, the input terminal and the output terminal of the integrated charge/discharge circuit are respectively connected to the energy storage unit and the power supply output terminal, so that electric energy stored in the energy storage unit is transmitted to the power supply output terminal through the integrated charge/discharge circuit. Whereas, if the input voltage is normal, the input terminal and the output terminal of the integrated charge/discharge circuit are respectively connected to the power supply output terminal and the energy storage unit, so that the energy storage unit is charged by the integrated charge/discharge circuit.

Abstract: An energy storage system and a method of controlling the energy storage system, the energy storage system including a power converting unit for converting a voltage output from the power generating system into a direct current (DC) link voltage, a bidirectional converter enabled to perform mutual conversion between an output voltage of the battery and the DC link voltage, a DC link unit for constantly maintaining a level of the DC link voltage, a bidirectional inverter for converting the DC link voltage into an alternating current (AC) voltage appropriate for the grid, and for converting an AC voltage of the grid into the DC link voltage, and an integrated controller for controlling the power converting unit, the bidirectional converter, and the bidirectional inverter, and for controlling operation modes of the energy storage system. In particular, the integrated controller may control operation modes in accordance with the DC link voltage.

Abstract: This invention offers an battery system that reduces a conversion loss due to a charger to reduce power consumption. The battery system has a solar battery, a battery module, a bypass route to bypass a charger to charge the battery module with DC power generated by the solar battery, and a control unit to control so that the electric power generated by the solar battery is supplied to the battery module through the bypass route when an output voltage of the solar battery is equal to or higher than a first predetermined voltage, that is higher than a terminal voltage of the battery module, and equal to or lower than a second predetermined voltage.

Abstract: Methods and systems for controlling power conversion systems. In one aspect, a power management system includes a first power conversion system coupled to a first energy source and a second power conversion system coupled to a second energy source, and a control system. The control system causes, while the first power conversion system is operating in an active mode and the second power conversion system is operating in a standby mode, the second power conversion system to exit the standby mode, the second power conversion system providing a reactive power flow upon exiting the standby mode. The control system causes the first power conversion system to provide a compensatory reactive power flow to compensate for at least a portion of the reactive power flow from the second power conversion system.

Abstract: A multiple power supply device including a power consuming unit, a plurality of power supply units, and a plurality of switching units is provided. The power consuming unit receives a plurality of power good signals, and outputs a plurality of power control signals accordingly. The power supply units output a plurality of working voltages respectively, and meanwhile output the power good signals. When the power consuming unit is in a working state and one of the power good signals is enabled, the power consuming unit enables the corresponding power control signal. When the power consuming unit is in a working state and a part of the power good signals are enabled, the power consuming unit enables one of the power control signals corresponding to the enabled power good signals. The switching units transmit the corresponding working voltage to the power consuming unit according to the enabled power control signal.

Abstract: A VoIP switch includes a first input Ethernet port configured to receive electrical power from a first power sourcing equipment, and a second input Ethernet port configured to receive electrical power from a second power sourcing equipment. The VoIP switch may be configured such that the first input Ethernet port is powered by the first power sourcing equipment concurrently with the second input Ethernet port being powered by the second power sourcing equipment.

Abstract: An uninterruptible power supply system, including: a plurality of uninterruptible power supply devices which are connected in parallel with respect to a load, and switch between power supplies supplying power to the load depending on states of the power supplies; a control unit controlling an operation of switching between the power supplies by the uninterruptible power supply devices; and a storage battery connected to the plurality of uninterruptible power supply devices in common. The uninterruptible power supply device has a converter converting AC power of an AC power supply into DC power, a contactor switching between the DC power converted by the converter and DC power input from the storage battery, and an inverter inverting the DC power into AC power and supplying the power to the load. The control unit deactivates the converter which does not contribute to supplying a power amount required for the load, of a plurality of converters.

Abstract: A system and method of power distribution and backup is provided. The power backup system includes a first uninterruptible power supply and a second uninterruptible power supply configured to drive a load in parallel. The first uninterruptible power supply and the second uninterruptible power supply are both connected through a direct connection to at least two power sources.

Abstract: A system and method of power distribution and backup is provided. The power backup system includes a first uninterruptible power supply and a second uninterruptible power supply configured to drive a load in parallel. The first uninterruptible power supply and the second uninterruptible power supply are both connected through a direct connection or through at least two switches to at least two power sources.

Abstract: A UPS system includes a power distribution assembly having a plurality of side faces and comprising an AC input and an AC output and at least two UPS assemblies having respective side faces confronting respective ones of the side faces of the power distribution assembly, each of the at least two UPS assemblies comprising a plurality of converter modules and an interconnection module configured to switchably couple AC inputs and AC outputs of the converter modules to respective ones of the AC input and the AC output of the power distribution assembly through conductors passing through the confronting side faces. The conductors may couple the power distribution assembly to the at least two UPS modules without the use of conduit and/or cable trays.

Abstract: The embodiments shown and described herein relate to a portable clean power generation and aggregation system. The system comprises a plurality of power generation units operable to generate DC electrical power, a power storage device, an inverter unit, and a main controller. The plurality of power generation units may include a solar power generation unit, a wind power generation unit, a hydro power generation unit, and a fuel-based power generation unit. The main controller is electrically coupled to the plurality of power generation units, the inverter controller, and the power storage device, and monitors DC electrical power generation by the plurality of power generation units, monitors DC electrical power received by the inverter, measures charge of the power storage device, and directs DC electrical power from the power storage device to the inverter.

Abstract: An uninterruptible power supply and a method of power saving thereof the uninterruptible power supply includes a switch and a backup power generator. The switch is coupled to a public power and a load, and backup power generator is coupled to the switch, the public power, and the load. Furthermore, the backup power generator is for controlling the switch and providing backup power for the load when the public power fails. Additionally, the backup power generator stops working in response to a trigger signal outputted from the load while the load is disabled.

Abstract: A charging system for a mobile device such as a computer, and method of operating the same are disclosed. The computer is a system that includes: a system unit being provided with power output to an operation power supply terminal to carry out an operation; a battery unit outputting battery power to the operation power supply terminal; and a solar power unit being provided with feedback on a voltage of the operation power supply terminal and outputting solar power corresponding to a predetermined operational level of the system unit to the operation power supply terminal.