The present disclosure provides systems and methods for controlling an electrical system. The electrical system includes a plurality of backup power sources, such as an electric vehicle battery, a photovoltaic system, and an energy storage system. The electrical system includes a service panel electrically coupled to a plurality of electrical loads. The electrical system includes an energy control system electrically coupled to the plurality of backup power sources, the service panel, and a utility grid. The energy control system converts to a plurality of settings based on the number of available backup power sources. The energy control system determines the availability of the backup power sources according to a predetermined protocol such that one or more backup power sources are prioritized over other backup power sources.

System, methods, and other embodiments described herein relate to safely activating a fuel cell (FC) within a generator. In one embodiment, a method includes initiating a test for sensitive systems of a generator using backup power including a battery. The method also includes powering an FC and a direct current (DC) converter within the generator to an operational level using the battery, wherein the DC converter stabilizes a circuit fed by the FC. The method also includes, upon successfully completing the test and powering the FC and the DC converter, energizing a load inverter after completing a non-critical sequence that controls support systems of the generator, wherein the DC converter stabilizes energy between the FC, the battery, and the load inverter.

A backup power supply is provided. The backup power supply provides batteries electrically coupled to a power cord for receiving power for charging the batteries and a power outlet for transmitting power for powering electrical equipment coupled to the power outlet. An inverter generator is operatively associated with the power cord, the batteries, and the power outlet in such a way that when the power cord experiences an electrical short the batteries switch from a reserve mode receiving power to a backup mode for transmitting power to the power outlet. The invertor generator is also adapted to sense reception of power through the power cord so as to switch from the backup mode to the reserve mode. Visible and audible indicators are provided for indicating the switching between the reserve mode and the backup mode.

An uninterruptible power supply includes a plurality of uninterruptible power supply modules each including a power converter, an input/output module that outputs power converted by the power converter to an outside of the uninterruptible power supply, and a disconnection module including a housing that houses disconnection switches that electrically disconnect each of the plurality of uninterruptible power supply modules individually.

Methods and systems for managing energy consumption during a power-loss event provide a backup power unit that can notify electronic devices of a switch to backup power. The electronic devices can then automatically minimize power consumption upon receiving such notification. The notification can take the form of one or more signals indicative of a backup power operational state. The signals may be sent to the electronic devices over any suitable wired or wireless connection. Depending on the particular operational states, the electronic devices can take one or more predefined backup power handling actions, such as reducing device functionality, entering low-power mode, performing a controlled shutdown, and the like. The particular actions taken may depend on the type of devices, such that certain devices may have power consumption priority over other devices. The above arrangement provides an intelligent way to reduce overall energy consumption during a power-loss event.

According to at least one aspect of the disclosure, a bi-directional AC/DC converter is provided comprising a DC-power connection configured to be coupled to a DC-power source, an AC-power connection configured to be coupled to at least one of an AC-power source or a load, a multiplexer having a plurality of multiplexer switches, at least one interleaved bridge circuit having a plurality of bridge switches coupled to the multiplexer, and a positive DC node and a negative DC node coupled to the plurality of multiplexer switches, wherein the plurality of bridge switches includes at least two bridge switches coupled between the AC-power connection and at least one of the positive DC node or the negative DC node.

A power supply apparatus is coupled to an AC power source, a critical load, and a general load. The power supply apparatus includes a UPS, a generator system, a power conversion system, and a controller. The power conversion system includes a first power conversion path and a second power conversion path. The first power conversion path is connected to the critical load and an output side, and the second power conversion path is connected to the general load and an input side. The first power conversion path and the second power conversion path are jointly connected to a DC bus. When the controller determines that the AC power source is abnormal, the controller controls disconnecting the AC power source, and activates the UPS to supply power to the critical load so as to enable the first power conversion path and disable the second power conversion path.

Systems and methods for supplying power at a medium voltage from an uninterruptible power supply (UPS) to a load without using a transformer are disclosed. The UPS includes an energy storage device, a single stage DC-DC converter or a two-stage DC-DC converter, and a multi-level inverter, each of which are electrically coupled to a common negative bus. The DC-DC converter may include two stages in a unidirectional or bidirectional configuration. One stage of the DC-DC converter uses a flying capacitor topology. The voltages across the capacitors of the flying capacitor topology are balanced and switching losses are minimized by fixed duty cycle operation. The DC-DC converter generates a high DC voltage from a low or high voltage energy storage device such as batteries and/or ultra-capacitors. The multi-level, neutral point, diode-clamped inverter converts the high DC voltage into a medium AC voltage using a space vector pulse width modulation (SVPWM) technique. The UPS may also include a small filter to remove harmonics in the AC voltage output from the multi-level inverter.

An uninterruptible power supply (UPS) is provided that includes a split direct current (DC) link having a first capacitor coupled between a positive DC link terminal and a first node, and a second capacitor coupled between the first node and a negative DC link terminal. The UPS also includes a rectifier coupled to an input of the split DC link and a controller coupled to the rectifier. The rectifier includes first, second, and third legs, wherein each leg is configured to convert a first alternating current (AC) voltage received from an AC source into a DC voltage to be provided to the split DC link, and a fourth leg configured to balance DC link voltages of the first and second capacitors. The controller is configured to maintain functionality of the rectifier during at least one of a partial utility power outage, a full utility outage, and a failure of at least one of the first, second, third, and fourth legs.

An uninterruptible power supply system includes a plurality of uninterruptible power supplies, each of which includes a rectifier and an inverter and switches between a normal operation mode for normal operation and a load simulation mode for simulating a load.