A power conversion circuit having a solid-state circuit breaker integrated therein is disclosed. With a disconnect switch between a utility source and the power conversion apparatus described for meeting UL489, the power conversion circuit includes an input connectable to an AC source, a rectifier circuit connected to the input to convert an AC power input to a DC power, and a DC link coupled to the rectifier circuit to receive the DC power therefrom. The rectifier circuit comprises a plurality of phase legs each including thereon an upper switching unit and a lower switching unit, wherein at least one of the upper and lower switching units on each phase leg comprises a bi-directional switching unit that selectively controls current and withstands voltage in both directions, so as to provide a circuit breaking capability that selectively interrupts current flow through the rectifier circuit, while maintaining original power conversion functionalities.

Embodiments herein describe a power converter in a wind turbine that includes a rectifier and an inverter. The rectifier includes a plurality of phase legs where each phase leg includes a plurality of full bridge cells configured to block fault current from flowing from a generator through the rectifier. Moreover, the wind turbine does not have any circuit breaker between the rectifier and the generator. The inverter also includes a plurality of phase legs where each phase leg includes a plurality of full bridge cells configured to block fault current from flowing from a transformer through the inverter. Moreover, the wind turbine does not have any circuit breaker between the inverter and the transformer.

Disclosed is a dynamic multi-functional power controller in collocation with a primary side coil, a switching unit, and a current sensing resistor, performing a power control process. An induced current is generated by a secondary side coil coupled with the primary side coil through electromagnetic interaction with a conduction current flowing through the primary side coil, and an output power is generated to supply an external load when the induced current flows through an output rectification unit and an output filter unit. The power control process includes detecting if any abnormal state occurs, stopping a driving signal, waiting for a period of time, and then re-sending the driving signal. Thus, the present invention provides protection for various kinds of peak loading, avoids high power state when an abnormal state is not resolved, and further reduces the average output power, thereby implementing power saving.

Apparatus and methods for supplying DC power to control circuitry of a matrix converter is provided. In certain embodiments, a matrix converter includes an array of switches having AC inputs for receiving a multi-phase AC input voltage and AC outputs for providing a multi-phase AC output voltage to a load, such as an electric motor. The matrix converter further includes control circuitry for opening or closing individual switches of the array, and a clamp circuit connected between the AC inputs and AC outputs of the array and operable to dissipate energy of the load in response to an overvoltage condition, such as an overvoltage condition arising during shutdown. The clamp circuit includes a switched mode power supply operable to generate a DC supply voltage for the control circuitry.

An AC-AC power converter, such as a motor soft starter, includes an input connectable to an AC source with a disconnect switch, an output connectable to an AC load, and phase lines connecting the input and output to transmit power. In-line solid-state switching blocks are connected between line terminals and load terminals of the AC source and AC load, respectively, such that each phase line includes a solid-state switching block connected thereto. Free-wheeling solid-state switching blocks are connected to the load terminals at one end and together at a common connection at another end, such that each phase line includes a free-wheeling solid-state switching block connected thereto. Each of the in-line and free-wheeling solid-state switching blocks comprises a bi-directional switching block that selectively controls current and withstands voltage in both directions. The switching blocks also provide soft-starter functions, variable speed control, and integrated circuit breaker protection capability.

Disclosed is a power conversion device having an AC conversion unit and a control unit that controls the AC conversion unit. The power conversion device also has: a temperature detection unit that outputs temperature data of the power conversion device; a current detection unit that outputs current data of an output of the AC conversion unit; a storage unit that stores specification data indicating a relationship between a rated current and a temperature specification and temperature data output by the detection unit; an overload protection unit that outputs a shutdown command to the control unit on the basis of the rated current and the current data output by the current detection unit; and a rating determination unit that acquires specification data and temperature data from the storage unit, determines a rated current corresponding to the acquired temperature data on the basis of the acquired specification data, and outputs the determined rated current to the overload protection unit.

A control unit of an electrical system is described. The control unit causes some of the switches in a power converter of the electrical system to not be shut down and not conducting upon detection of a fault current caused by a line-to-line fault. Instead, the control unit causes at least one of the switches to be switched-on and conducting to allow the some of the fault current to flow through the at least one switch, before activating a protection device that creates an open circuit and breaks the fault.

A system and method for mitigating overvoltage on a DC link of a power converter of an electrical power system connected to a power grid includes receiving a voltage feedback signal from the DC link for a predetermined time period. The method also includes determining a rate of change of the voltage feedback signal during the predetermined time period. Further, the method includes predicting a future voltage value on the DC link as a function of the voltage feedback signal and the rate of change of the voltage feedback signal. Moreover, the method includes controlling the electrical power system based on the future voltage value.

According to one aspect, an uninterruptible power supply system is provided including an input configured to receive input power, an interface configured to be coupled to a backup power supply and to receive backup power from the backup power supply, an output configured to provide output power derived from at least one of the input power and the backup power to a load, a power converter coupled to the input, a capacitor, and a shoot-through detector coupled to the capacitor. The shoot-through detector is configured to obtain a first voltage value indicative of a first voltage across the capacitor, obtain a second voltage value indicative of a second voltage across the capacitor, compare the first voltage value to the second voltage value, determine, based on the comparison, that the capacitor is experiencing a shoot-through condition, and provide an output signal indicative of the shoot-through condition.

Disclosed is a dynamic multi-functional power controller in collocation with a primary side coil, a switching unit, and a current sensing resistor, performing a power control process. An induced current is generated by a secondary side coil coupled with the primary side coil through electromagnetic interaction with a conduction current flowing through the primary side coil, and an output power is generated to supply an external load when the induced current flows through an output rectification unit and an output filter unit. The power control process includes detecting if any abnormal state occurs, sopping a driving signal, waiting for a period of time, and then re-sending the driving signal. Thus, the present invention provides protection for various kinds of peak loading, avoids high power state when abnormal state being not resolved, and further reduces the average output power, thereby implementing power saving.