A control method is disclosed to prevent false triggering of over-current protection. A power converter comprises high-side and low-side switches connected in series between an input power line and a ground line, for driving a resonant circuit to resonate. The power converter includes a detector detecting the resonant circuit to provide a detection signal representing a magnitude of resonance in the resonant circuit. A duty cycle of one of the high-side and low-side switches is detected, and a threshold is determined in response to the duty cycle. An over-current protection is triggered based on the threshold and the detection signal. When the over-current protection is triggered, at least one of the high-side and low-side switches stops providing power to the resonant circuit, and the resonance subsides.

A power control device includes: an output voltage controller configured to control an output voltage based on a feedback voltage corresponding to the output voltage; and an overvoltage protector configured to continue or stop the operation of the output voltage controller based on a first detection result of whether the output voltage has exceeded an output voltage threshold value and a second detection result of whether the feedback voltage has fallen to or below a feedback voltage threshold value.

The invention relates to a device for operating a voltage converter (1), in particular a DC converter, of a motor vehicle, which voltage converter has at least two parallel-connected converter strands (4, 5) which are connected between a high-voltage side (2) and a low voltage side (3) of the voltage converter (1) for converting the voltage, having at least one cooling device (8) carrying a coolant (9) and assigned to the converter strands (4, 5), wherein each of the converter strands (4, 5) is assigned at least one temperature sensor (6, 7), comprising the following steps: a) detecting an input voltage, an output voltage and an operating current of each converter strand (4, 5), b) detecting a current converter strand temperature by means of the respective temperature sensor (6, 7), c) determining a respective coolant temperature as a function of the values detected in steps a) and b), d) comparing the two determined coolant temperatures (T_1, T_2) with each other and e) determining the serviceability of the temperature sensors (6, 7) on the basis of the result of the comparison.

A direct current (DC)/DC conversion circuit includes an input end, a power circuit, and an output end, a bypass circuit that is a unidirectional conduction circuit, and a switch disposed between the input end and the power circuit, where the input end is configured to be coupled to an external power supply to receive power to the DC/DC conversion circuit. The bypass circuit is coupled between the input end and the power circuit, the bypass circuit is disposed between the switch and the power circuit, and the bypass circuit is coupled to the power circuit in parallel. The switch is configured to be closed when the input end is reversely coupled to the external power supply to enable a current from a positive electrode of the external power supply to flow back to a negative electrode of the external power supply through the bypass circuit and the switch.

A power conversion circuit includes a first and a second power converters for generating a first and a second driving voltages respectively. The second power converter is a switching converter. In a short-circuit detection mode, the first driving voltage is regulated to the first driving level, and the second power converter is configured to operate in a pulse frequency modulation mode to regulate the second driving voltage to a short-circuit detection level, and when a switching frequency of the second power converter exceeds a threshold frequency, a short-circuit condition between the second driving voltage and the first driving voltage is determined.

In preferred embodiments, a short circuit protection system for a wide-band gap power electronics converter composed of multiple half-bridge legs is presented. The main approaches of the system are a single point of monitoring (SPM) for multiple switching legs, and non-invasive implementation and fast speed of the short circuit current detection. Ultra-high frequency (UHF) AC current, tens or hundreds of MHz, flowing through the DC-link capacitors represents the short circuit current occurred at the multiple switching legs. To capture the UHF AC current, a non-invasive MHz bandwidth magnetic current sensor is applied to the PCB conduction path of the converter. In this digest, simulation results of the short circuit current representation through the DC-link network and the magnetic field distribution in PCB layout for the selection of the proper location of the detection, and experimental results showing the UHF AC current sensing performance are presented.

Various implementations described herein are directed to a methods and apparatuses for disconnecting, by a device, elements at certain parts of an electrical system. The method may include measuring operational parameters at certain locations within the system and/or receiving messages from control devices indicating a potentially unsafe condition, disconnecting and/or short-circuiting system elements in response, and reconnection the system elements when it is safe to do so. Certain embodiments relate to methods and apparatuses for providing operational power to safety switches during different modes of system operation.

Gate Drive Apparatus and Control Method for Switched Capacitor Converter A power converter includes a plurality of power switches connected in series between a system ground and an input voltage bus, wherein an upper power switch located between the input voltage bus and an output terminal of the power converter, and immediately adjacent to the output terminal of the power converter is configured as an isolation switch including two back-to-back connected diodes and a bulk terminal, and wherein a connection of the bulk terminal is reconfigurable, and a driver configured to drive the upper power switch immediately adjacent to the output terminal of the power converter.

This disclosure describes a protection circuit configured to protect a power converter. The protection circuit may be configured to determine when the power converter is operating in a tristate mode, and upon determining that the power converter is operating in the tristate mode, to disable a supply to the power converter based on a comparison of a switch node voltage on a switch node of the power converter to a feedback node voltage on an output node of the power converter.

An apparatus includes a first gate drive transistor and a second gate drive transistor connected in series, a common node of the first gate drive transistor and the second gate drive transistor connected to a gate of a power switch, the second gate drive transistor configured as a bulk switch having a bulk terminal connected to a bulk terminal of the power switch, a first auxiliary transistor connected between the bulk terminal and a source of the power switch, a second auxiliary transistor coupled between the gate of the power switch and a system ground, and a third auxiliary transistor coupled between a logic control ground and the system ground, wherein the second auxiliary transistor and the third auxiliary transistor are configured to pull the gate of the power switch and the logic control ground down to the system ground in response to a turn off of the apparatus.