A switching system is disclosed having a switching arm with a high-side switch and a low-side switch. A control system switches the switching arm alternately between a first configuration, in which the high-side switch is open and the low-side switch is closed, and a second configuration, in which the high-side switch is closed and the low-side switch is open. The control system commands, for each switching operation, the opening of the switch that is initially closed, and then, at the end of a dead time, commands the closure of the switch that is initially open. The system has device for measuring a switch voltage present between the terminals of one of the switches. For each switching operation, the control system, following the command to open the switch initially closed, monitors the measured switch voltage, and determine the dead time for the switching operation based on the monitored switch voltage.

Provided is a novel multi-level inverter with mixed device types and methods of controlling same. This novel multi-level inverter topology and control method allows the use of high frequency switching devices for controlled PWM switching, while also using lower frequency switching devices for directional switches. This combination of high frequency PWM switching devices with low frequency directional switching devices allows a cost reduction without a significant performance degradation.

Provided is a novel multi-level inverter with mixed device types and methods of controlling same. This novel multi-level inverter topology and control method allows the use of high frequency switching devices for controlled PWM switching, while also using lower frequency switching devices for directional switches. This combination of high frequency PWM switching devices with low frequency directional switching devices allows a cost reduction without a significant performance degradation.

A shoot-through protection circuit includes a current sensor providing a sensor signal connected to a comparator input via at least a burden resistor. A switch protection circuit including a protection input connected to an output of the comparator and a plurality of outputs. Each of the outputs is connected to a corresponding switch in a plurality of stacked switches. Wherein the switch protection circuit is configured to drive each switch of the plurality of stacked switches open in response to a positive output signal from the comparator.

A shoot-through protection circuit includes a current sensor providing a sensor signal connected to a comparator input via at least a burden resistor. A switch protection circuit including a protection input connected to an output of the comparator and a plurality of outputs. Each of the outputs is connected to a corresponding switch in a plurality of stacked switches. Wherein the switch protection circuit is configured to drive each switch of the plurality of stacked switches open in response to a positive output signal from the comparator.

A low EMI driver apparatus includes: a driver circuit configured to generate a driving signal according to a switch control signal, so as to drive at least one switch; and a driving strength control circuit configured to randomly control a driving strength of the driver circuit, thereby reducing an EMI generated when the at least one switch is driven according to the driving signal. In a specific form of the low EMI driver apparatus, the at least one switch includes plural switches, and the low EMI driver apparatus further includes: a dead time control circuit configured to randomly control a dead time between ON times of the plural switches, so as to reduce the EMI generated when the switches are driven according to the driving signal.

A low EMI driver apparatus includes: a driver circuit configured to generate a driving signal according to a switch control signal, so as to drive at least one switch; and a driving strength control circuit configured to randomly control a driving strength of the driver circuit, thereby reducing an EMI generated when the at least one switch is driven according to the driving signal. In a specific form of the low EMI driver apparatus, the at least one switch includes plural switches, and the low EMI driver apparatus further includes: a dead time control circuit configured to randomly control a dead time between ON times of the plural switches, so as to reduce the EMI generated when the switches are driven according to the driving 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.

In an embodiment, a method for operating an ACF converter includes: turning on a low-side transistor that is coupled between a primary winding of a transformer and a reference terminal to cause a forward current to enter the primary winding, turning off the low-side transistor; after turning off the low-side transistor, turning on a high-side transistor that is coupled between the primary winding and a clamp capacitor to cause a reverse current to flow through the primary winding; and after turning on the high-side transistor, when an overcurrent of the reverse current is not detected, keeping the high-side transistor on for a first period of time, and turning off the high-side transistor after the first period of time, and when the overcurrent of the reverse current is detected, turning off the high-side transistor without keeping the high-side transistor on for the first period of time.