Tm4 Inc.

Astec International Limited

Dana Tm4 Inc.

Jean-Marc Cyr

Maalainine El Yacoubi

Pascal Fleury

Mohammed Amar

Jianhong Xu

Martin Houle

François Messier

Ruisheng Shi

Benoit Blanchard St-Jacques

George Bursuc

Christian Pronovost

Jane Roundell

Gabriel Rakotonirina

Francois Daniel

Jean Ricard

Marion Nourry

Richard Verreau

The present disclosure relates to a circuit for providing a current from a source to a load. A commutation cell includes a main switch that controls a voltage applied by the source to the load. An opposite switch maintains the current in the load when the load is disconnected from the source by the main switch. The opposite switch returns the load current to the main switch when the main switch connects again the load to the source. The disclosed circuit configuration reduces recovery current, losses and electromagnetic losses. A synchronizing controller controls opening and closing sequences of the main switch and of the opposite switch. The disclosed circuit can provide a DC-DC voltage converter. Combining two such circuits can provide a DC-AC voltage converter.

Circuits for softening switching phases in voltage converters

The present disclosure relates to a commutation cell and to a compensation circuit for limiting overvoltage across the power electronic switch of the commutation cell and for limiting a recovery current in a freewheel diode of the commutation cell. The power electronic switch has a parasitic emitter inductance. A variable gain compensation circuit generates a feedback from a voltage generated across the parasitic inductance of the emitter of the power switch at turn-on or turn-off of the power electronic switch. The compensation circuit provides the feedback to a control of the power electronic switch to reduce the voltage generated on the parasitic emitter inductance. A power converter including the commutation cell with the compensation circuit is also disclosed.

Commutation cell and compensation circuit therefor

The present disclosure relates to a power converter configured for limiting switching overvoltage. The power converter comprises a bottom commutation cell that includes a bottom power electronic switch and a bottom compensation circuit connected to a bottom parasitic inductance. The bottom compensation circuit applies a sample of the voltage induced across the bottom parasitic inductance at turn-off of the bottom power electronic switch to the reference node of the bottom gate driver. The power converter also comprises a top commutation cell that includes top power electronic switch and a top compensation circuit connected to the bottom parasitic inductance. The top compensation circuit applies a sample of the voltage induced across the bottom parasitic emitter upon turn-off of the top power electronic switch to the reference node of the top gate driver. The top and bottom commutation cells are part of a loop, being connected at a junction of the collector of the bottom power electronic switch and the emitter of the top power electronic switch.

Power converter configured for limiting switching overvoltage

A physical topology for receiving top and bottom power electronic switches comprises a top collector trace connected to a positive voltage power supply tab and having a connection area for a collector of a top power electronic switch, a bottom emitter trace connected to a negative voltage power supply tab and having a connection area for an emitter of the bottom power electronic switch, and a middle trace connected to a load tab and having a connection area for an emitter of the top power electronic switch and a connection area for a collector of the bottom power electronic switch. Sampling points are provided on the traces for voltages on the emitters of the top and bottom power electronic switches, on the trace for voltage of the collector of the bottom power electronic switch, and on the negative voltage power supply tab. The topology defines parasitic inductances.

Physical topology for a power converter

A turn-off overvoltage limiting for IGBT is described herein. The injection of a sample of the overvoltage across the IGBT in the gate drive to slow down the slope of the gate voltage decrease only during the overvoltage above a predetermined value is described herein. Techniques to increase the parasitic inductance to allow the control to limit an overvoltage at turn off of the second IGBT are also described herein.

Turn-off overvoltage limiting for IGBT

A commutation cell is configured for limiting switching overvoltage. The commutation cell includes a power electronic switch having a parasitic emitter inductance through which a voltage is generated upon turning off of the power electronic switch. The commutation cell also includes a dynamically controlled compensation circuit connected to the parasitic emitter inductance. The compensation circuit applies a controllable portion of the voltage generated through the parasitic emitter inductance at turn-off of the power electronic switch to control the voltage generated through the parasitic emitter inductance. A power converter includes a pair of commutation cells and a compensation circuit of the commutation cell.

Commutation cell, power converter and compensation circuit having dynamically controlled voltage gains

The present topology for controlled power switch module is concerned with a module where the parasitic inductance of the emitter of the top power switch is optimized to allow the injection of a sample of the overvoltage across this parasitic inductance in the gate drive circuit of the top power switch as a feedback to slow down the slope of the falling gate voltage during an overvoltage that is above a predetermined value.

Topology for controlled power switch module

The present disclosure relates to a power converter configured for limiting switching overvoltage. The power converter comprises a pair of commutation cells. Each commutation cell includes a power electronic switch and a gate driver connected to a gate of the power electronic switch. A reference of the gate driver of a first commutation cell is connected to a ground of the power converter while a reference of the gate driver of a second commutation cell is connected to a collector of the power electronic switch of the first commutation cell. The gate driver of the second commutation cell has no negative voltage power input, either through using a single voltage power supply or by connecting a negative voltage connection of the dual voltage power supply to ground.

The present disclosure relates to a compensation circuit for independently controlling turn-on and turn-off of a power electronic switch through a gate driver. The compensation circuit includes a circuit path sampling a first portion of a voltage induced across an inductance of the power electronic switch at turn-on. Another circuit path samples a second portion of the voltage induced across the inductance of the power electronic switch at turn-off. The compensation circuit further includes a gate driver reference connection configured to respectively supply the sampled portions of the voltage during turn-on and turn-off of the power electronic switch. A compensation circuit controlling a first power electronic switch in parallel with a second power electronic switch, a commutation cell and a power converter having a pair of parallel legs, in which each power electronic switch is provided with the compensation circuit, are also disclosed.

Compensation circuit, commutation cell and power converter controlling turn-on and turn-off of a power electronic switch

The present invention is generally concerned with an inductance assembly that is so configured and sized as to be inserted inside the cooling assembly of an electric machine to thereby decrease the overall volume of the machine.

Inductance assembly for an electric machine

A boost converter topology is disclosed that includes a resonant network comprising a snubber inductive element having a primary winding connected in series to a first resonant diode that is connected, at a first node, to two series connected additional resonant diodes and a secondary winding coupled to a fourth resonant diode connected to the first node. The present invention has the advantage of reducing the energy stored in the parasitic capacitor of the first resonant diode by a factor of four at the turn off of the main control switch. This reduction is achieved by allowing only a small amount of energy transfer to the snubber inductive element so that it does not turn the two additional resonant diodes on before the auxiliary switch is turned on, thus reducing losses and EMI associated with turning on the auxiliary switch.

Boost topology having an auxiliary winding on the snubber inductor

A current management system for a telecommunications power system includes a power bus, a communications bus, and a distribution module connected to the power bus and the communications bus. A plurality of loads are connected to the distribution module. A plurality of rectifier modules are connected to the power bus, the communications bus and to at least one alternating current source. Each of the rectifier modules includes a neuron that generates a rectifier current signal for the rectifier module. A master controller that is connected to the communications generates an average current signal from the rectifier current signals. The neurons generate a first rectifier control signal that slightly modifies current that is output by the rectifier modules based upon the average current signal and the rectifier current signal. A temperature sensor senses a temperature of each of the rectifier modules. The master controller generates an average temperature signal from the rectifier temperature signals. The neurons generate a second rectifier control signal that slightly modifies the current that is output by the rectifier modules using the average temperature signal and the rectifier temperature signal. In another current management system, the neurons communicate to establish a highest rectifier current. The neurons of each rectifier module adjust their rectifier voltages based on the highest rectifier current to approximate current balancing.

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Candiac, Canada

Jean-Marc Cyr