Control Techniques Limited

Yasa Limited

Emerson Climate Technologies Gmbh

Nidec Control Techniques Limited

Simon David Hart

Tim Woolmer

Samuel David Ahearn

Jacob A Groshek

Richard Mark Wain

Richard Phillips

Stephen Berry

Wayne M Penn, Ii

Christopher Stuart Malam

Michael Cade

Tom Hillman

Wayne M Penn

Dilesh Arvind Raut

Antony John Webster

Graham Law

Francesca Bernardine Bumpus

Dhananjay Dattatray Kapatkar

Described herein is a method of cooling a plurality of power devices, where the power devices are arranged as a plurality of switches used to generate a three-phase output AC voltage. Based on power device stress data, one or more switches (associated with one or more phase output AC voltages) may be identified as requiring more cooling than other of the switches. The switches are controlled to apply a common mode component voltage to each of the three phases for at least a portion of one or more output AC voltage segments. The common mode component voltage has a maximum amplitude that is sufficient to clamp the phase AC output voltage of the identified phase(s) to the positive supply rail voltage and/or negative rail supply voltage when the respective phase AC voltage is approaching respectively the positive supply rail voltage or negative supply rail voltage to cool the identified switch(es).

Method and apparatus for cooling one or more power devices

We describe techniques to reduce DC ripple voltage in an inverter by determining a plurality of switching events for each of the three phases in each Pulse Width Modulation (PWM) period. The switching events provide a desired target output voltage for the respective PWM period. From this determination of the switching events, a comparison can be made to determine a first time period between a first and second switching event across all of the phases, and a second time period between the second and a third switching event across all of the phases. The timing of one or more switching events in only one of the phases in the respective PWM period is adjusted in response to the determined time period being greater than a threshold in order to reduce the determined first or second time period.

Method and apparatus for generating a three-phase voltage

A modulation technique is described in which a controller modulates the output AC voltages to introduce an offset to the phase that is most positive or most negative such that the phase is clamped to the +dc supply when the respective phase is most positive and to the &#x2212;dc supply rail when most negative. The offset is provided by introducing a common mode component voltage to all of the phases over a plurality of output angle segments. In order to reduce the Noise Vibration and Harshness (NVH) and EMI, the common mode component voltage amplitude is varied over the output angles within the respective segment between a minimum and a maximum in order to control a slew rate of the rising or falling edges of the three phase AC output voltages.

A semiconductor arrangement and an inverter incorporating the semiconductor arrangement, in particular to an inverter for use with traction power units e.g. for on and off road vehicles and stationary power inversion, are described. In the arrangement, semiconductor devices are thermally and electrically coupled to a heatsink as a module. The heatsink is configured as a bus bar to electrically connect the one or more semiconductor devices together to transmit power between the one or more semiconductor devices. The semiconductor devices may be cooled using the structure to which they are attached, and also immersed in a cooling medium to further increase the cooling of the device.

Inverter arrangement

The present invention relates to a semiconductor cooling arrangement for cooling semiconductor devices, such as power semiconductors. The semiconductor cooling arrangement comprises one or more semiconductor assemblies located in a chamber within a housing. The housing comprises inlet and outlet ports for receiving and outputting a cooling medium. The chamber is flooded with a cooling medium to cool the assemblies. The assemblies themselves each comprise a heatsink and one or more semiconductor power devices thermally coupled to the heatsink. The heatsink comprises heat exchanging elements in the form of a plurality of holes in the heatsink extending through the heatsink from one surface to another surface such that the cooling medium flows through the holes to extract heat from the heatsink.

Semiconductor cooling arrangement

A drive controller for a motor of a compressor includes a drive circuit that applies voltages to windings of the motor. The drive controller includes a speed control module that controls the drive circuit to rotate the motor at a requested speed. The drive controller includes a speed determination module that generates the requested speed. The drive controller includes a defrost module that enables a defrost mode in response to a defrost command. While the defrost mode is enabled, the defrost module causes the speed determination module to (i) ramp the requested speed down from a speed demand to a defrost speed and (ii) maintain the requested speed at the defrost speed for a predetermined period of time.

Variable speed compressor control with sound-controlled defrost mode

Embodiments of the present invention relate to an a method, apparatus and computer program product for controlling the operation of a drive unit comprising a plurality of switching modules arranged to receive a DC electricity supply and generate an AC electricity supply for driving a load from the received DC electricity supply, the AC electricity supply being generated by the switching of the plurality of switching modules between a conducting state and a non-conducting state. The method comprises receiving one or more characteristics associated with each of the switching modules, comparing, for each switching module of the plurality of switching modules, a characteristic of the switching module with an equivalent characteristic associated with one or more other switching modules of the plurality of switching modules, and controlling a time period during which one or more of the plurality of switching modules are in the conducting state in accordance with a result of the comparison.

Control system and method

A method and a control system for a multiphase-phase inverter system, the control system comprising an electric current detection circuit and a processor, wherein each phase of an electrical cycle is separated into a plurality of sections, inputs from the electric current detection circuit are received, each input indicating a measured phase current, and a phase current is calculated in each section, wherein the phase current calculation in at least one of the sections is determined from a changing ratio of the value of the phase current calculated from the measured values of the other phase currents in the multiphase system and the measured value of the phase.

Control system for multi-phase rotary machines

There is provided a method and control system for controlling a switching device in a power converter according to a modulation scheme. The switching device couples a direct current (DC) source to provide an alternating current (AC) output at a particular switching frequency. The method comprises the step of, in each switching period, switching the switching device between active configurations providing a finite voltage at the output and inactive configurations providing a zero voltage at the output. The ratio between the total period of time in which the switching device is in an active configuration and the total period of time in which the switching device is in an inactive configuration is the same for each switching period and is determined according to the desired voltage at the AC output. However, in each switching period, there are at least two time periods in which the switching device is in an inactive configuration, and the ratio between those at least two time periods is changed in dependence on temperature associated with the switching device.

Modulation of switching signals in power converters

The present disclosure relates to a power conversion system comprising a transformer comprising first, second, and third inductive coupling elements, a first power supply arranged to provide a voltage across the first coupling element, a second power supply arranged to provide a voltage across the second coupling element, an output arranged to receive a voltage from the third coupling element. In use, the voltage across the first coupling element and the voltage across the second coupling element are arranged to induce a voltage in the third coupling element. The system also comprises a control arrangement arranged to independently control the operation of the first and second power supplies.

Power conversion system

A drive controller for a motor of a compressor includes a drive circuit that applies voltages to windings of the motor. A speed control module controls the drive circuit to rotate the motor at a requested speed. A speed determination module generates the requested speed based on a speed demand from a system controller. A lost rotor control module identifies a lost rotor condition and, in response to identifying the lost rotor condition, instructs the speed determination module to set the requested speed to an override speed that is lower than the speed demand. The lost rotor control module identifies the lost rotor condition in response to a comparison of a speed error with an adaptive threshold. The speed error is based on a difference between requested and estimated speeds of the motor. During first and second system states, the adaptive threshold is set to first and second thresholds, respectively.

Variable speed compressor control with lost rotor mitigation

A method arranged to control a motor for driving a load is disclosed. The motor and load form at least a part of a system and the motor comprises a stator arranged to produce a varying magnetic field responsive to an applied AC voltage and a rotor arranged to rotate responsive to the varying magnetic field produced by the stator, the rotor rotating at a speed synchronized to a frequency of the applied AC voltage. The method comprises receiving a target rotor speed, determining a voltage level for the applied AC voltage for producing a magnetic field having magnetic flux of sufficient magnitude to maintain the rotor in synchronization with the frequency of the applied AC voltage when rotating at the target speed of rotation. The voltage level is determined in accordance with the target rotor speed and a model of the system. The model comprising a plurality of model elements, wherein one or more of the model elements is indicative of an effect of one or more parts of the system on rotation of the rotor when the speed of the rotor is constant and one or more of the model elements are indicative of an effect of one or more parts of the system on rotation of the rotor when the speed of the rotor is dynamic. The method further comprising applying the applied AC voltage to the stator at the determined voltage level and at a frequency required to provide the target rotor speed.

Rotor control

A rectifier circuit comprising an AC input, at least one thyristor coupled to the AC input, a DC bus driven by the at least one thyristor, a controller arranged to: derive a first current in the DC bus, derive a maximum current demand on the DC bus, and provide a trigger signal to the at least one thyristor based on the derived maximum current and the derived first current.

Rectifier charge rate controller

There is provided a method and control system for reducing noise in a power converter by controlling a switching device in the power converter according to a modulation scheme. The switching device couples a direct current (DC) source to provide an alternating current (AC) output at a particular switching frequency. The method includes the step of, in each switching period, switching the switching device between active configurations providing a finite voltage at the output and inactive configurations providing a zero voltage at the output. The ratio between the total period of time in which the switching device is in an active configuration and the total period of time in which the switching device is in an inactive configuration is the same for each switching period and is determined according to the desired voltage at the AC output.

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Welshpool, United Kingdom

Simon David Hart