Vehicle battery power supply monitoring and management systems and methods for use with replaceable and rechargeable batteries, which among other things is configured to facilitate the sequential usage of each battery from a plurality of batteries secured within a vehicle based on a measurement of the condition of the battery, and facilitate the speed, ease and convenience in the removal and replacement of secured batteries.

Provided is an energy storage system including: an external power input unit receiving uninterrupted external power; a battery storing electric power; a power adjustment device adjusting the uninterrupted external power and the power of the battery, the battery including a battery module with one or more battery cells; a battery management system; a main switch disposed on a power path between the battery module and the battery management system and a path between the battery module and the power adjustment device; and a wake-up relay receiving a wake-up signal from the power adjustment device and transmitting the wake-up signal to the battery management system.

A request is received for a higher torque from a torque controller than is possible from a power supply. The torque controller is coupled to a motor and the power supply, and the motor is coupled to an actuator. The actuator ultimately establishes resistance for a user in an exercise. An energy storage device is discharged to the motor in order to generate the higher torque, wherein the energy storage device is indirectly coupled to the torque controller.

A rechargeable battery jump starting device with a discharged battery pre-conditioning system to facilitate boosting the discharged battery to jump start a vehicle or equipment engine. The pre-conditioning increases the operating voltage to the discharged battery during the pre-conditioning phase.

A rechargeable battery jump starting device with a discharged battery pre-conditioning system to facilitate boosting the discharged battery to jump start a vehicle or equipment engine. The pre-conditioning increases the operating voltage to the discharged battery during the pre-conditioning phase.

Embodiments of systems and methods disclosed provide a hydraulic fracturing unit that includes a reciprocating plunger pump configured to pump a fracturing fluid and a powertrain configured to power the reciprocating plunger pump. The powertrain includes a prime mover and a drivetrain, the prime mover including a gas turbine engine. The hydraulic fracturing unit also includes auxiliary equipment configured to support operation of the hydraulic fracturing unit including the reciprocating plunger pump and the powertrain. A power system is configured to power the auxiliary equipment. The power system includes a power source and a power network. The power source is configured to generate power for the auxiliary equipment. The power network is coupled to the power source and the auxiliary equipment, and configured to deliver the power generated by the power source to the auxiliary equipment. Associated systems including a plurality of hydraulic fracturing units are also provided.

Embodiments of systems and methods disclosed provide a hydraulic fracturing unit that includes a reciprocating plunger pump configured to pump a fracturing fluid and a powertrain configured to power the reciprocating plunger pump. The powertrain includes a prime mover and a drivetrain, the prime mover including a gas turbine engine. The hydraulic fracturing unit also includes auxiliary equipment configured to support operation of the hydraulic fracturing unit including the reciprocating plunger pump and the powertrain. A power system is configured to power the auxiliary equipment. The power system includes a power source and a power network. The power source is configured to generate power for the auxiliary equipment. The power network is coupled to the power source and the auxiliary equipment, and configured to deliver the power generated by the power source to the auxiliary equipment. Associated systems including a plurality of hydraulic fracturing units are also provided.

A distributed power system including multiple (DC) batteries each DC battery with positive and negative poles. Multiple power converters are coupled respectively to the DC batteries. Each power converter includes a first terminal, a second terminal, a third terminal and a fourth terminal. The first terminal is adapted for coupling to the positive pole. The second terminal is adapted for coupling to the negative pole. The power converter includes: (i) a control loop adapted for setting the voltage between or current through the first and second terminals, and (ii) a power conversion portion adapted to selectively either: convert power from said first and second terminals to said third and fourth terminals to discharge the battery connected thereto, or to convert power from the third and fourth terminals to the first and second terminals to charge the battery connected thereto. Each of the power converters is adapted for serial connection to at least one other power converter by connecting respectively the third and fourth terminals, thereby forming a serial string. A power controller is adapted for coupling to the serial string. The power controller includes a control part adapted to maintain current through or voltage across the serial string at a predetermined value.

A distributed power system including multiple (DC) batteries each DC battery with positive and negative poles. Multiple power converters are coupled respectively to the DC batteries. Each power converter includes a first terminal, a second terminal, a third terminal and a fourth terminal. The first terminal is adapted for coupling to the positive pole. The second terminal is adapted for coupling to the negative pole. The power converter includes: (i) a control loop adapted for setting the voltage between or current through the first and second terminals, and (ii) a power conversion portion adapted to selectively either: convert power from said first and second terminals to said third and fourth terminals to discharge the battery connected thereto, or to convert power from the third and fourth terminals to the first and second terminals to charge the battery connected thereto. Each of the power converters is adapted for serial connection to at least one other power converter by connecting respectively the third and fourth terminals, thereby forming a serial string. A power controller is adapted for coupling to the serial string. The power controller includes a control part adapted to maintain current through or voltage across the serial string at a predetermined value.

A respiratory therapy device generates a flow of breathable gas for therapy. The apparatus may include a flow generator in a housing to generate the breathable gas flow. The flow generator may have an operating voltage for such operations. The device may include a battery pack that is engageable with the housing. The battery pack may be configured to power the flow generator and may include a stand-by circuit configured to switch between stand-by and operating modes. The stand-by circuit may be configured to provide a stand-by operations voltage while in the stand-by mode that is less than an operating voltage of the flow generator and may be configured to detect current demand of the flow generator with the stand-by operations voltage while in stand-by mode such as for enabling an increase voltage from the battery pack to produce the operating voltage in the operating mode for the flow generator.