A circuit includes a high-side transistor pair and a low-side transistor pair having a common intermediate node. The high-side transistor pair includes a first transistor having a control node and a current flowpath therethrough configured to provide a current flow line between a supply voltage node and the intermediate node, and a second transistor having a current flowpath therethrough coupled to the control node of the first transistor. The low-side transistor pair includes a third transistor having a control node and a current flowpath therethrough configured to provide a current flow line between the intermediate node and the reference voltage node, and a fourth transistor having a current flowpath therethrough coupled to the control node of the third transistor. Testing circuitry is configured to be coupled to at least one of the second transistor and the fourth transistor to apply thereto a test-mode signal.

A control method includes sequentially updating a next cycle pulse width modulation command for each of an upper switch and lower switch of a phase leg of a power converter according to an order defined by timing of a rising edge of the next cycle pulse width command for one of the switches relative to a rising edge of a previous cycle pulse width command for the one of the switches.

A control method includes sequentially updating a next cycle pulse width modulation command for each of an upper switch and lower switch of a phase leg of a power converter according to an order defined by timing of a rising edge of the next cycle pulse width command for one of the switches relative to a rising edge of a previous cycle pulse width command for the one of the switches.

A load testing device includes a connection unit to which a power source being tested is connected, a hydrogen generating unit that performs electrolysis based on power supplied from the power source being tested to generate hydrogen, two or more supply units to which hydrogen obtained in the hydrogen generating unit passes and to which a portable tank is removably attached, and an operational unit that has a load amount adjustment switch and a display unit. The load amount of the hydrogen generating unit is switched depending on an operational state of the load amount adjustment switch. The display unit displays at least one of an attachment status of the portable tank and a filling status of hydrogen in the two or more supply units.

A load testing device includes a connection unit to which a power source being tested is connected, a hydrogen generating unit that performs electrolysis based on power supplied from the power source being tested to generate hydrogen, two or more supply units to which hydrogen obtained in the hydrogen generating unit passes and to which a portable tank is removably attached, and an operational unit that has a load amount adjustment switch and a display unit. The load amount of the hydrogen generating unit is switched depending on an operational state of the load amount adjustment switch. The display unit displays at least one of an attachment status of the portable tank and a filling status of hydrogen in the two or more supply units.

A power supply device includes a controller configured to output, to a power converter, a command value to control at least one of a voltage or a current of power output from the power converter, and acquire a measurement value measured by a measurement unit. The controller is configured to, while power conversion operation is being performed by the power converter, change the command value and determine a deterioration of the power converter based on a mode of a change in the measurement value measured by the measurement unit due to a change in the command value.

A power supply device includes a controller configured to output, to a power converter, a command value to control at least one of a voltage or a current of power output from the power converter, and acquire a measurement value measured by a measurement unit. The controller is configured to, while power conversion operation is being performed by the power converter, change the command value and determine a deterioration of the power converter based on a mode of a change in the measurement value measured by the measurement unit due to a change in the command value.

A ground-fault detecting device includes: a first detecting module, having a first input terminal, a second input terminal, and a third input terminal coupled to a first-phase electric power, a second-phase electric power, and a third-phase electric power on an AC side of a photovoltaic power generating system respectively, for sampling voltages of the first-phase electric power, the second-phase electric power, and the third-phase electric power to generate a first sampled voltage, a second sampled voltage, and a third sampled voltage respectively; and a controller, coupled to the first detecting module, for determining if a ground-fault occurs in the AC side before the photovoltaic power generating system is connected to a grid according to the first sampled voltage, the second sampled voltage, and the third sampled voltage; wherein the controller generates an alarm signal when the ground-fault occurs in the AC side.

A device for measuring a current of a three-phase inverter according to an embodiment of the present invention comprises: a current detection element connected to the lower end of one of three lower switches comprising an inverter; a current measurement unit for measuring a current by using the current detection element and the other two lower switches, to which the current detection element is not connected; and a current correction unit for correcting a second current value and a third current value measured using the two lower switches, on the basis of the relationship between a first current value measured using the current detection element and the second and third current values.

Provided are a method and device for testing an adaptor, and a storage medium. The method is applicable to the device. The method includes the following. A test signal is sent to the adaptor. Detect a first voltage, where the first voltage is outputted in a preset first duration by the adaptor according to the test signal. A working state of the adaptor is determined according to the first voltage.