A reverse polarity protection device includes a protection unit, a detection unit, and a control unit electrically connected between a power supply device and a load device. The detection unit is electrically connected to the power supply device for detecting the polarity of an output signal of the power supply device, and the control unit is electrically connected to the detection unit and the protection unit. The detection unit outputs a detection signal to the control unit according to a detection result of the polarity of the output signal. If the detection signal shows that the polarity of the output signal is reverse, the control unit will control the protection unit to form an open circuit between the power supply device and load device to stop transmitting the output signal of the power supply device to the load device and achieve a reverse polarity protection effect of the load device.

A voltage converting circuit and a control circuit thereof are provided. The control circuit includes a comparator, a clock generator, and a boost circuit. The comparator compares an input voltage with an output voltage to generate a comparison signal. The clock generator generates a clock signal according to the comparison signal to enable the clock signal to have a first frequency in a first time interval and to have a second frequency in a second time interval. The first frequency is higher than the second frequency. The first time interval occurs before the second time interval. The boost circuit receives the clock signal, pulls up a control signal of a driving switch in the first time interval according to a first driving capability, and generates the control signal in the second time interval according to a second driving capability. The first driving capability is greater than the second driving capability.

The ECU includes first and second power terminals, first and second voltage limiting elements, first and second diodes, and a power supply IC. A voltage is applied to the first power terminal from a battery, and a voltage is applied to the second power terminal from the battery via a start switch. The first voltage limiting element is provided between the first power terminal and an input terminal of the power supply IC. The cathode of the first diode is connected to the input terminal of the power supply IC. The second voltage limiting element is provided between the second power terminal and the anode of the first diode. The cathode of the second diode is connected to the anode of the first diode, and the anode is grounded. A limit voltage of the first voltage limiting element is greater than a limit voltage of the second voltage limiting element.

A load drive circuit includes a power source terminal (PST), a power source and a load terminal connecting a load to the power source. A semiconductor switch connects the PST to the load terminal. A control circuit includes an output terminal for opening/closing the semiconductor switch. A freewheeling circuit includes a freewheeling diode and a protection switch blocks a current from the power source to the semiconductor switch when the power source is connected in a reverse manner. A first terminal connects the control circuit to a first fixed potential and a second terminal connects an anode of the freewheeling diode to a second fixed potential. A connection circuit includes a connection switch connecting the output terminal and the first terminal. The connection circuit connects the output terminal to the first terminal when a rise in a potential difference between the first terminal and the second terminal is detected.

A network service and transformer safety protector on a secondary side of a network transformer tank system. The network service and transformer safety protector is positioned between the network transformer and a secondary network distribution system and is configured to connect and disconnect a transformer from the secondary network. The network service and transformer safety protector is attached to the outside of the transformer tank.

A reverse current protection circuit for a switch circuit includes a reverse current control circuit and an enable/disable circuit coupled to the reverse current control circuit. The reverse current control circuit is coupled to an input terminal and an output terminal of the switch circuit, and disconnects the output terminal of the switch circuit from the input terminal of the switch circuit when an output voltage of the switch circuit is higher than a first predetermined voltage. The enable/disable circuit disables the reverse current control circuit for a first predetermined time period when the output voltage of the switch circuit becomes lower than the first predetermined voltage after being higher than the first predetermined voltage, and enables the reverse current control circuit after the first predetermined time period.

The ECU includes first and second power terminals, first and second voltage limiting elements, first and second diodes, and a power supply IC. A voltage is applied to the first power terminal from a battery, and a voltage is applied to the second power terminal from the battery via a start switch. The first voltage limiting element is provided between the first power terminal and an input terminal of the power supply IC. The cathode of the first diode is connected to the input terminal of the power supply IC. The second voltage limiting element is provided between the second power terminal and the anode of the first diode. The cathode of the second diode is connected to the anode of the first diode, and the anode is grounded. A limit voltage of the first voltage limiting element is greater than a limit voltage of the second voltage limiting element.

A new infrastructure for mobile devices and electronic loose equipment, preferably an aircraft infrastructure, is designed to be deployed for both new production aircraft and the after-market installed base for all parts of the aircraft that have human interaction, such as the galley, cockpit or cabin. The architecture is designed around two main objectives: creating stylized and functional products with flexibility in design and providing reliability and maintainability for operators while integrating power and charging mediums to those devices. This architecture is composed of several elements that as a whole complete our new architecture for mobile devices and electronic loose equipment design.

Provided is an anti-islanding protection system. The system is applied to a low-voltage distributed generation resource (DGR) and includes a box, a reverse power protector, a protection module and an output controller. The reverse power protector has an end connected to a first current transformer and has another end connected to the output controller. The reverse power protector is configured to provide reverse power protection for the low-voltage DGR. The output controller has an end connected to the protection module and the reverse power protector and has another end connected to a grid-connection switch of the low-voltage DGR. The output controller is configured to control the grid-connection switch to turn off when reserve power is detected. The protection module has an end connected to a second current transformer and has another end connected to the output controller. The protection module is configured to provide low-frequency protection, over-frequency protection, over-voltage protection and low-voltage protection for the low-voltage DGR.

An electronic circuit for providing protection for an energy supply for a receiving device, includes: a supply path for connecting the receiving device to a voltage source, wherein the supply path has at least one first switching component in series with a second switching component, and also a measuring resistor, a functional assembly for providing protection against an overcurrent in the supply path, a functional assembly for detecting a connected receiving device, a functional assembly for providing protection against a polarity reversal for the voltage of the supply path, and a functional assembly for detecting a ground short for the supply path.