Abstract: A bi-directional switch for an inductive machine is described. The bi-directional switch may include a first power semiconductor transistor with a first source, a first drain, and a first gate. The bi-directional switch may further include a second power semiconductor transistor with a second source, a second drain, and a second gate. The bi-directional switch may include the second source connected to the first source. The bi-directional switch may include a soft-starter device including a control circuit configurable to provide a first control signal to the first power semiconductor transistor and a second control signal to the second power semiconductor transistor.

Abstract: Systems, methods, techniques and apparatuses of a semiconductor control system are disclosed. One exemplary embodiment is a method for protecting a semiconductor switch comprising receiving a first voltage during a second blanking period following a first blanking period; determining whether a short circuit fault is occurring by comparing the first voltage to a fast detection threshold corresponding to a first value of a drain-source voltage of the semiconductor switch; if a short circuit is not occurring: receiving a second voltage after the second blanking period ends; determining whether a short circuit fault is occurring by comparing the second voltage to a slow detection threshold corresponding to a second value of the drain-source voltage; and if a short circuit fault is occurring, opening the semiconductor switch, wherein the first value of the drain-source voltage is greater than the second value of the drain-source voltage.

Abstract: A bi-directional switch for an inductive machine is described. The bi-directional switch may include a first power semiconductor transistor with a first source, a first drain, and a first gate. The bi-directional switch may further include a second power semiconductor transistor with a second source, a second drain, and a second gate. The bi-directional switch may include the second source connected to the first source. The bi-directional switch may include a soft-starter device including a control circuit configurable to provide a first control signal to the first power semiconductor transistor and a second control signal to the second power semiconductor transistor.

Abstract: Systems, methods, techniques and apparatuses of power switches are disclosed. One exemplary embodiment is a power switch comprising a first semiconductor device and a second semiconductor device coupled together in a first anti-series configuration between a first terminal and a second terminal; a third semiconductor device and a fourth semiconductor device coupled together in a second anti-series configuration between the first terminal and the second terminal; a controller configured to operate the power switch to simultaneously conduct a first portion of a load current from the first terminal to the second terminal by closing the first semiconductor device and the second semiconductor device, and to conduct a second portion of the load current from the first terminal to the second terminal by closing the third semiconductor device and the fourth semiconductor device.

Abstract: A soft switching resonant converter is disclosed. The converter includes a power switch operable to connect and disconnect a DC link rail node and an output node. A resonant capacitor is coupled with the power switch. An auxiliary leg is coupled with a DC link midpoint node and the output node. An active damper is coupled in series with the resonant capacitor and the output node and is controllable to provide a first resistance of the active damper in a first state and a second resistance of the active damper in a second state, the first resistance having a lower magnitude than the second resistance. A driver controls the damper switch to provide a first resistance during the soft switching operation of the power switch and a second resistance after the soft switching operation of the power switch.

Abstract: Systems, methods, techniques and apparatuses of power switches are disclosed. One exemplary embodiment is a power switch comprising a first semiconductor device and a second semiconductor device coupled together in a first anti-series configuration between a first terminal and a second terminal; a third semiconductor device and a fourth semiconductor device coupled together in a second anti-series configuration between the first terminal and the second terminal; a controller configured to operate the power switch to simultaneously conduct a first portion of a load current from the first terminal to the second terminal by closing the first semiconductor device and the second semiconductor device, and to conduct a second portion of the load current from the first terminal to the second terminal by closing the third semiconductor device and the fourth semiconductor device.

Abstract: A soft switching resonant converter is disclosed. The converter includes a power switch operable to connect and disconnect a DC link rail node and an output node. A resonant capacitor is coupled with the power switch. An auxiliary leg is coupled with a DC link midpoint node and the output node. An active damper is coupled in series with the resonant capacitor and the output node and is controllable to provide a first resistance of the active damper in a first state and a second resistance of the active damper in a second state, the first resistance having a lower magnitude than the second resistance. A driver controls the damper switch to provide a first resistance during the soft switching operation of the power switch and a second resistance after the soft switching operation of the power switch.

Abstract: Systems, methods, techniques and apparatuses of short circuit protection are disclosed. One exemplary embodiment is a method for protecting a semiconductor switch comprising receiving a measurement corresponding to an electrical characteristic of the semiconductor switch; determining a semiconductor switch resistance value using the received measurement; estimating a junction temperature of the semiconductor switch using the semiconductor switch resistance value; determining a short circuit voltage threshold using the estimated junction temperature; comparing the short circuit voltage threshold to a test voltage corresponding to a drain-source voltage of the semiconductor switch; determining a short circuit condition is occurring in response to comparing the short circuit voltage threshold and the test voltage; and opening the semiconductor switch in response to determining the short circuit condition is occurring.

Abstract: Direct-current-to-direct-current (DC-DC) power converters that include two or more multi-quadrant, multi-level, DC-DC, switching converter subcircuits, connected in parallel at respective input and output sides, so as to provide a multi-channel, multi-quadrant, multi-level configuration, are disclosed. The DC-DC power converters further include a control circuit configured to control the switching converter subcircuits so that corresponding switching semiconductors in each of the switching converter subcircuits are switched in an interleaved manner. In some embodiments, each of the switching converter subcircuits is a three-level, neutral-point-clamped, four-quadrant DC-DC converter circuit. In other embodiments, each of the switching converter subcircuits is a three-level, neutral-point-clamped, two-quadrant DC-DC converter circuit. In any of these embodiments, a filter capacitor may be connected between across a pair of output terminals at the output sides of the switching converter subcircuits.

Abstract: Systems, methods, techniques and apparatuses of short circuit protection are disclosed. One exemplary embodiment is a method for protecting a semiconductor switch comprising receiving a measurement corresponding to an electrical characteristic of the semiconductor switch; determining a semiconductor switch resistance value using the received measurement; estimating a junction temperature of the semiconductor switch using the semiconductor switch resistance value; determining a short circuit voltage threshold using the estimated junction temperature; comparing the short circuit voltage threshold to a test voltage corresponding to a drain-source voltage of the semiconductor switch; determining a short circuit condition is occurring in response to comparing the short circuit voltage threshold and the test voltage; and opening the semiconductor switch in response to determining the short circuit condition is occurring.

Abstract: Systems, methods, techniques and apparatuses of a semiconductor control system are disclosed. One exemplary embodiment is a method for protecting a semiconductor switch comprising receiving a first voltage during a second blanking period following a first blanking period; determining whether a short circuit fault is occurring by comparing the first voltage to a fast detection threshold corresponding to a first value of a drain-source voltage of the semiconductor switch; if a short circuit is not occurring: receiving a second voltage after the second blanking period ends; determining whether a short circuit fault is occurring by comparing the second voltage to a slow detection threshold corresponding to a second value of the drain-source voltage; and if a short circuit fault is occurring, opening the semiconductor switch, wherein the first value of the drain-source voltage is greater than the second value of the drain-source voltage.

Abstract: A multi-phase power converter includes two or more multi-phase, bi-directional, multi-level, switching power converter subcircuits, connected in parallel at respective AC and DC sides, so as to provide a multi-channel, bi-directional, multi-level configuration. The AC sides of the switching converter subcircuits are directly coupled to one another and to a multi-phase AC input via series interface reactors, and the DC sides of the switching converter subcircuits are directly connected to one another and to a common split-capacitor bank at each level of the multi-level outputs of the switching converter subcircuits. A control circuit is configured to selectively control one or more switching semiconductor devices in each of the switching converter subcircuits.

Abstract: Unique systems, methods, techniques and apparatuses of semiconductor failure prognostication. One exemplary embodiment is a power converter comprising a semiconductor switch and a converter control system. The converter control system is configured to turn on the semiconductor switch, measure a first voltage and a current during reverse conduction, estimate junction temperature of the semiconductor device, turn off the semiconductor device, measure a second voltage after turning off the semiconductor device, determine a resistance value using the second voltage measurement, determine an expected resistance value, predict a failure of the semiconductor device using the resistance value and the expected resistance value, and transmit a semiconductor device failure warning.

Abstract: Unique systems, methods, techniques and apparatuses of semiconductor failure prognostication. One exemplary embodiment is a power converter comprising a semiconductor switch and a converter control system. The converter control system is configured to turn on the semiconductor switch, measure a first voltage and a current during reverse conduction, estimate junction temperature of the semiconductor device, turn off the semiconductor device, measure a second voltage after turning off the semiconductor device, determine a resistance value using the second voltage measurement, determine an expected resistance value, predict a failure of the semiconductor device using the resistance value and the expected resistance value, and transmit a semiconductor device failure warning.

Abstract: Unique systems, methods, techniques and apparatuses of a gate drive system are disclosed. One exemplary embodiment is a drive circuit electrically coupled to a main switching device including a first inverter, a first inverter controller, an air core transformer, at least one rectifier, at least two smoothing capacitors, a current buffer stage, and a detection circuit. The first inverter controller is structured to operate the first inverter in a first mode and a second mode. The air core transformer is structured to receive the converted AC power from the first inverter. The detection circuit is structured to detect a first mode of the first inverter and a second mode of the first inverter, and operate the current buffer stage based on a detected first mode of the inverter and a detected second mode of the first inverter.

Abstract: Unique systems, methods, techniques and apparatuses of a gate drive system are disclosed. One exemplary embodiment is a drive circuit electrically coupled to a main switching device comprising a first inverter, a first inverter controller, an air core transformer, at least one rectifier, at least two smoothing capacitors, a current buffer stage, and a detection circuit. The first inverter controller is structured to operate the first inverter in a first mode and a second mode. The air core transformer is structured to receive the converted AC power from the first inverter. The detection circuit is structured to detect a first mode of the first inverter and a second mode of the first inverter, and operate the current buffer stage based on a detected first mode of the inverter and a detected second mode of the first inverter.

Abstract: A converter for connecting a voltage source to a load includes a plurality of ICBT (integrated capacitor blocked transistor) cells configured as switches and connected in series to form a series connection path, a main capacitor connected across the series connection path, and a controller. Each ICBT cell includes a main transistor disposed in the series connection path and a series connected auxiliary transistor and auxiliary capacitor coupled in parallel with the main transistor. The controller is operable to develop a voltage across the main capacitor which exceeds a voltage rating of the ICBT cells, by switching the ICBT cells so as to commutate current within the individual ICBT cells without the ICBT cells providing active power to the load so that power flow is from the voltage source, to the main capacitor, to the load and not through the auxiliary transistors and the auxiliary capacitors.

Abstract: A multi-phase power converter includes two or more multi-phase, bi-directional, multi-level, switching power converter subcircuits, connected in parallel at respective AC and DC sides, so as to provide a multi-channel, bi-directional, multi-level configuration. The AC sides of the switching converter subcircuits are directly coupled to one another and to a multi-phase AC input via series interface reactors, and the DC sides of the switching converter subcircuits are directly connected to one another and to a common split-capacitor bank at each level of the multi-level outputs of the switching converter subcircuits. A control circuit is configured to selectively control one or more switching semiconductor devices in each of the switching converter subcircuits.

Abstract: Direct-current-to-direct-current (DC-DC) power converters that include two or more multi-quadrant, multi-level, DC-DC, switching converter subcircuits, connected in parallel at respective input and output sides, so as to provide a multi-channel, multi-quadrant, multi-level configuration, are disclosed. The DC-DC power converters further include a control circuit configured to control the switching converter subcircuits so that corresponding switching semiconductors in each of the switching converter subcircuits are switched in an interleaved manner. In some embodiments, each of the switching converter subcircuits is a three-level, neutral-point-clamped, four-quadrant DC-DC converter circuit. In other embodiments, each of the switching converter subcircuits is a three-level, neutral-point-clamped, two-quadrant DC-DC converter circuit. In any of these embodiments, a filter capacitor may be connected between across a pair of output terminals at the output sides of the switching converter subcircuits.