The invention relates to a system 1 for controlling a voltage converter comprising a plurality of high-side switches forming a high group and a plurality of low-side switches forming a low group, the control system 1 comprising: a module 10 for measuring a voltage V of the DC voltage source B, a module 11 for comparing the measured voltage V with a first safety threshold OV1, a control module 12 for controlling a first group of switches so as to close chosen from the high group or the low group, if the comparison module 11 indicates that the measured voltage V is higher than the first safety threshold OV1.

A switching power converter is provided with an overvoltage protection circuit that monitors the differential data signal voltages in a data interface such as a USB data interface powering a load device to detect soft short conditions.

A microcontroller unit for controlling a three-level inverter including delayed fault protection is provided. The microcontroller unit includes an input port configured to receive a trip signal from a fault detection module, and a plurality of EPWM modules, each configured to control a power switch within the three-level inverter. The microcontroller unit includes an auxiliary EPWM module configured to receive the trip signal and produce a delayed trip signal, and processing circuitry coupled with the input port, the plurality of EPWM modules, and the auxiliary EPWM module. The processing circuitry is configured to, in response to activation of the trip signal, direct one of the plurality of EPWM modules to shut off its corresponding power switch upon activation of the trip signal, and to direct a different one of the plurality of EPWM modules to shut off its corresponding power switch upon activation of the delayed trip signal.

A rotating machine power conversion device is obtained which achieves operational continuation in a rotational speed range in which the operational continuation is enabled, even when a single phase of an electrical power conversion device made of switching devices causes a disconnection or turn-off failure. The rotating machine power conversion device comprises: a normality-case/abnormality-case current control device selection device for transferring between a normality-case current control device and an abnormality-case current control device in accordance with a determination result of an abnormality determination device; and an abnormality-case current control device/power conversion halt device selection device, using a rotational speed calculation device, for transferring between the abnormality-case current control device used when a rotational speed is lower than that being prespecified, and the power conversion halt device used when a rotational speed is higher than that being prespecified.

A short circuit protection apparatus for a power conversion apparatus supplying power to a load via a plurality of switches connected to each other in parallel includes Ma current detectors each configured to detect a sum of currents flowing through two or more switches among the plurality of switches so as to output a detection signal indicative of the sum that is detected, wherein Ma is 1 less than M, which is the number of the plurality of switches, and a short circuit determiner configured to determine, based on detection signals obtained from the respective Ma current detectors, occurrence of short circuit failure in the plurality of switches to output a cutoff instruction signal for stopping on-off drive of the plurality of switches.

A load abnormality detecting circuit for an inverter to detect abnormality of a load during an operation of the inverter which has a switching element and a phase synchronizing loop controlling an output frequency to be a resonance frequency of the load, the load abnormality detecting circuit includes a phase shift detection part that detects a phase shift between an output voltage and an output current which are applied from the inverter to the load and sends an abnormal load signal based on the detected phase shift. The switching element including a self-arc-extinguishing element and a reflux diode connected in reversely parallel to the self-arc-extinguishing element. The phase shift detection part detects advance and delay of a phase of the output current with respect to the output voltage.

One general aspect includes methods, systems, and apparatus, including computer programs encoded on a computer storage medium, for fault protection of a bidirectional wireless power transfer system. The method includes the actions of detecting, by control circuitry of a wireless power transfer device, a fault for the bidirectional wireless power transfer system. Identifying an operating personality of the wireless power transfer device and a hardware configuration of the wireless power transfer device. Identifying, in response to detecting the fault and based on the operating personality and the hardware configuration, protection operations for protecting the wireless power transfer device from the fault. Controlling operations of the wireless power transfer device according to the protection operations. Other implementations of this aspect include corresponding systems, circuitry, controllers, apparatus, and computer programs, configured to perform the actions of the methods, encoded on computer storage devices.

A method of operating a power conversion system including converting variable frequency AC voltage to constant frequency AC voltage by a power converter, setting a first peak current reset threshold above operating currents previously observed during steady state short circuit current regulation in by a controller of the power converter, setting a second peak current reset threshold at a current lower than the previously observed steady state short-circuit regulation point observed during previous operation during steady state short circuit current regulation by the controllers of the power converter, resetting inverter converter AC output regulating voltage to 0 volts, and ramping AC output regulating voltage back up into steady-state operation when the second a peak current reset threshold is exceeded.

A ground fault detection method for a power converter is provided, including: measuring, by a voltage sensor, a first voltage and a second voltage respectively, and converting the first voltage and the second voltage into a first digital voltage signal and a second digital voltage signal; receiving, by a controller, the first digital voltage signal and the second digital voltage signal, extracting a corresponding feature quantity of the first voltage and a corresponding feature quantity of the second voltage according to the first digital voltage signal and the second digital voltage signal; and further determining a type of the ground fault of the power converter and locating a ground fault; and when the power converter has a ground fault, shutting down the power converter.

The present invention discloses a self-test leakage protector with a timing function, comprising a leakage protection module, a timer module, a DC power supply module, and a DC power supply module control switch, wherein the DC power supply module control switch is connected between the DC power supply module and the leakage protection module, or between input AC power and the DC power supply module that supplies power to the leakage protection module, and is in an off state under a standby condition; according to a timing function requirement, the timer sends a signal of turning off or turning on the DC control switch; and when the turning-on signal is sent, the switch is closed, such that the leakage protection module is powered on for power-on reset, followed by a self-test of a leakage function, and if the self-test is passed, power is supplied to a load, and the self-test is carried out every time before power is supplied to the load. In the invention, the timing function of the timer is integrated in the self-test leakage protector capable of self testing, so the leakage protector is a separate product having a timing function with high safety, low standby power consumption and a low cost.