In some examples, an Emergency Power Off (EPO) device can be connected to a non-EPO port of a computing device, and the EPO device can provide an EPO signal via the non-EPO port to a manager connected to an energy storage device of the computing device, wherein the EPO signal comprises instructions to power off the energy storage device.

An electronic control unit includes a first controller, a second controller, and a determination portion. The first controller includes a first control portion that determines whether or not supply of power from a battery to the first controller is interruptible. The second controller includes a regulator that regulates power supplied from the battery to the first controller and a second control portion that controls the regulator. The determination portion determines whether or not the supply of power is forcibly interruptible even when the first control portion does not determine that the supply of power is interruptible. When the determination portion determines that the supply of power is forcibly interruptible, the second control portion controls the regulator to interrupt the supply of power from the battery to the first controller.

A power supply device includes a power output terminal, a power converter and an electronic circuit breaker. In view of operation of the electronic circuit breaker, when an electric appliance that acts as a load is connected between the power output terminal and a ground terminal, the electronic circuit breaker is activated to output voltage from the power converter to the power output terminal so as to charge the electric appliance. When the electric appliance is done with charging and is removed, the electronic circuit breaker is deactivated to prevent voltage of the power converter from being outputted to the power output terminal. Thus, even if the power output terminal is exposed, the power output terminal won't output power to result in electric shock because of users' inadvertent contact when no electric appliance is being charged, thereby enhancing operational safety.

An extended base of a mobile terminal and a power supply management method for the extended base is described herein. When a mobile terminal is inserted into an extended base, an enable circuit of the extended base is electrically connected to the mobile terminal and generates an enable signal, and a switch circuit outputs a voltage under control of the enable signal, so that a power supply of the extended base supplies power under control of the voltage. When the mobile terminal is removed from the extended base, the enable circuit stops generating the enable signal, and the switch circuit stops outputting the voltage, so that the power supply cannot supply power under the control of the voltage.

A system and method includes a power control circuit for controlling first power from a power supply provided to a first circuit includes a first stage and a second stage. The first stage includes a low power energy detector and a first power switch. The low power energy detector is configured to provide second power via the first switch in response to energy. The second stage includes a signal detector configured to detect a characteristic of a signal associated with the energy in response to the second power. The signal detector is configured have the first power provided to the first circuit in response to the characteristic being detected.

A working method of a modular uninterruptible power supply (UPS) includes: obtaining working parameters of the modular UPS, where the working parameters include an input voltage parameter, a load parameter, and a battery parameter; and adjusting a working mode of a power module in the modular UPS according to at least one of the working parameters of the modular UPS, so that not all power modules are in a same working mode, where the modular UPS includes K working modules, and 2K.

In some examples, an Emergency Power Off (EPO) device can be connected to a non-EPO port of a computing device, and the EPO device can provide an EPO signal via the non-EPO port to a manager connected to an energy storage device of the computing device, wherein the EPO signal comprises instructions to power off the energy storage device.

A power supply method includes the following steps: detecting whether a battery is installed in a system; delivering a control signal to a power conversion circuit by a controller when it is determined that the battery is not installed in the system; turning on part of a plurality of transistors and turning off the other part of the plurality of transistors by the power conversion circuit according to the control signal and a reference signal, so that an input voltage is delivered to a receiving terminal of the system from a sending terminal of the system through a current path.

A system and method includes a power control circuit for controlling first power from a power supply provided to a first circuit includes a first stage and a second stage. The first stage includes a low power energy detector and a first power switch. The low power energy detector is configured to provide second power via the first switch in response to energy. The second stage includes a signal detector configured to detect a characteristic of a signal associated with the energy in response to the second power. The signal detector is configured have the first power provided to the first circuit in response to the characteristic being detected.

In case the operational power production level of a multi-phase DC-AC power converter decreases, a controller may be configured to determine that a switching leg or switching legs of DC-AC power converter are to be disabled based on a power criterion to reduce losses incurred by the DC-AC power converter. The controller may be configured to select one of more of the switching legs, based on a selection criterion, and disable the selected switching leg or switching legs so as to reduce phase imbalance or degradation of the switching legs.