Abstract: The present invention relates to microspheres comprising a core material, wherein the microsphere is perfectly spherical and has a moisture content less than 1%, and the method of manufacturing the same. The present invention is useful in the manufacture of sustained and modified release active pharmaceutical ingredient (API) microspheres, as a free flowing excipient for mini-tablets and in the manufacture of API dispersions.

Abstract: Microspheres comprising a core material, wherein the microspheres have a circularity greater than 0.95 and an aspect ratio greater than 0.95, and methods of manufacturing the same. The microspheres may be useful in the manufacture of sustained and modified release active pharmaceutical ingredient (API) microspheres, as a free flowing excipient for mini-tablets and in the manufacture of API dispersions.

Abstract: A variable speed drive includes a converter connected to an AC power source, a DC link connected to the converter, and an inverter connected to the DC link. The inverter converts DC voltage into an output AC power having a variable voltage and frequency. The inverter includes at least one power electronics module and associated control circuitry; a heat sink in thermal communication with the power electronics module and in fluid communication with a manifold. The manifold includes a tubular member having at least one vertical member portion and at least one horizontal member portion in fluid communication. A plurality of ports conduct cooling fluid into and out of the manifold. A bracket attaches the manifold to a structural frame. Brackets are provided for attachment of power electronics modules to the manifold.

Abstract: Microspheres comprising a core material, wherein the microspheres have a circularity greater than 0.95 and an aspect ratio greater than 0.95, and methods of manufacturing the same. The microspheres may be useful in the manufacture of sustained and modified release active pharmaceutical ingredient (API) microspheres, as a free flowing excipient for mini-tablets and in the manufacture of API dispersions.

Abstract: Microspheres comprising a core material, wherein the microspheres have a circularity greater than 0.95 and an aspect ratio greater than 0.95, and methods of manufacturing the same. The microspheres may be useful in the manufacture of sustained and modified release active pharmaceutical ingredient (API) microspheres, as a free flowing excipient for mini-tablets and in the manufacture of API dispersions.

Abstract: A variable speed drive includes a converter connected to an AC power source, a DC link connected to the converter, and an inverter connected to the DC link. The inverter converts DC voltage into an output AC power having a variable voltage and frequency. The inverter includes at least one power electronics module and associated control circuitry; a heat sink in thermal communication with the power electronics module and in fluid communication with a manifold. The manifold includes a tubular member having at least one vertical member portion and at least one horizontal member portion in fluid communication. A plurality of ports conduct cooling fluid into and out of the manifold. A bracket attaches the manifold to a structural frame. Brackets are provided for attachment of power electronics modules to the manifold.

Abstract: A variable speed drive includes a converter connected to an AC power source, a DC link connected to the converter, and an inverter connected to the DC link. The inverter converts DC voltage into an output AC power having a variable voltage and frequency. The inverter includes at least one power electronics module and associated control circuitry; a heat sink in thermal communication with the power electronics module and in fluid communication with a manifold. The manifold includes a tubular member having at least one vertical member portion and at least one horizontal member portion in fluid communication. A plurality of ports conduct cooling fluid into and out of the manifold. A bracket attaches the manifold to a structural frame. Brackets are provided for attachment of power electronics modules to the manifold.

Abstract: A variable speed drive includes a converter connected to an AC power source, a DC link connected to the converter, and an inverter connected to the DC link. The inverter converts DC voltage into an output AC power having a variable voltage and frequency. The inverter includes at least one power electronics module and associated control circuitry; a heat sink in thermal communication with the power electronics module and in fluid communication with a manifold. The manifold includes a tubular member having at least one vertical member portion and at least one horizontal member portion in fluid communication. A plurality of ports conduct cooling fluid into and out of the manifold. A bracket attaches the manifold to a structural frame. Brackets are provided for attachment of power electronics modules to the manifold.

Abstract: Microspheres comprising a core material, wherein the microspheres have a circularity greater than 0.95 and an aspect ratio greater than 0.95, and methods of manufacturing the same. The microspheres may be useful in the manufacture of sustained and modified release active pharmaceutical ingredient (API) microspheres, as a free flowing excipient for mini-tablets and in the manufacture of API dispersions.

Abstract: The present invention relates to microspheres comprising a core material, wherein the microsphere is perfectly spherical and has a moisture content less than 1%, and the method of manufacturing the same. The present invention is useful in the manufacture of sustained and modified release active pharmaceutical ingredient (API) microspheres, as a free flowing excipient for mini-tablets and in the manufacture of API dispersions.

Abstract: The present invention relates to microspheres and compositions comprising a plurality of microspheres, wherein the microspheres are perfectly spherical and have a moisture content less than 1%, and the method of manufacturing the same. The present invention is useful in the manufacture of sustained and modified release active pharmaceutical ingredient (API) microspheres, as a free flowing excipient for mini-tablets and in the manufacture of API dispersions.

Abstract: A converter module for a variable speed drive having a semiconductor device for precharge is described. The precharge circuit includes switching modules, one switching module with a first semiconductor switch connected in parallel or series with a second semiconductor switch. The second semiconductor switch is switched on and off during the precharge operation in order to limit the inrush current into the DC Link. After the precharge operation, the second semiconductor switch is turned on all the time and acts like a diode. The second semiconductor device may have a lower maximum current rating than the main semi-conductor devices. The lower current rated semiconductor device experience the same short circuit current as the higher current rated semiconductor device. The lower current rated semiconductor device can be supplied with a larger gate to emitter voltage than the higher current rated semiconductor device to equalize current between semiconductor devices.

Abstract: A grounding system for a semiconductor module of a variable speed drive includes a first conductive layer, a second conductive layer; a substrate disposed between the first conductive layer and the second conductive layer; and a base attached to the second conductive layer, the base being connected to earth ground via a grounding harness. The first conductive layer is in electrical contact with the semiconductor module and the substrate, and electrically insulated from the second conductive layer by the substrate. The second conductive layer is in electrical contact with the substrate and disposed between the substrate and the base in electrical communication with an earth ground. The first conductive layer, the substrate and the second conductive layer form a capacitance path between the semiconductor module and the base as well as electrical conductors and the base for reduction circulating currents within the semiconductor module.

Abstract: A cooling member for a variable speed drive is disclosed. The cooling member includes including at least two channels, each channel including at least one inlet and at least one outlet, a first passageway configured to provide fluid to the at least two channels through the at least one inlet of each channel, a second passageway configured to receive fluid from the at least one outlet of each channel the at least two channels, and a connector to connect the cooling member to a second cooling member.

Abstract: A converter module for a variable speed drive having a semiconductor device for precharge is described. The precharge circuit includes switching modules, one switching module with a first semiconductor switch connected in parallel or series with a second semiconductor switch. The second semiconductor switch is switched on and off during the precharge operation in order to limit the inrush current into the DC Link. After the precharge operation, the second semiconductor switch is turned on all the time and acts like a diode. The second semiconductor device may have a lower maximum current rating than the main semi-conductor devices. The lower current rated semiconductor device experience the same short circuit current as the higher current rated semiconductor device. The lower current rated semiconductor device can be supplied with a larger gate to emitter voltage than the higher current rated semiconductor device to equalize current between semiconductor devices.

Abstract: A chiller system is provided with a compressor, a condenser, and an evaporator connected in a closed refrigerant loop. A motor is connected to the compressor to power the compressor. A variable speed drive is connected to the motor. The variable speed drive is arranged to receive an input AC power at a fixed input AC voltage and a fixed input frequency and provide an output power at a variable voltage and variable frequency to the motor. The variable voltage has a maximum voltage greater in magnitude than the fixed input AC voltage and the variable frequency has a maximum frequency greater than the fixed input frequency. The variable speed drive includes a converter connected to an AC power source providing the input AC voltage, the converter is arranged to convert the input AC voltage to a DC voltage. A DC link is connected to the converter. The DC link is arranged to filter and store the DC voltage from the converter. An inverter is connected to the DC link.

Abstract: A drive system for a compressor of a chiller system includes a variable speed drive. The variable speed drive receives an input AC power at a fixed input AC voltage and a fixed input frequency, and provides an output AC power at a variable voltage and variable frequency. The variable speed drive includes a converter connected to an AC power source. The converter is arranged to convert the input AC voltage to a DC voltage. A DC link is connected to the converter and configured to filter and store the DC voltage from the converter. An inverter is connected to the DC link. A motor is connectable to the compressor for powering the compressor. A controller is arranged to control switching in the converter and the inverter. The controller is arranged to apply randomized pulse width modulation to vary the switching frequency of transistors in the converter and the inverter at each switching cycle. The motor may be a permanent magnet synchronous motor.

Abstract: A drive system for a compressor of a chiller system includes a variable speed drive. The variable speed drive is arranged to receive an input AC power at a fixed AC input voltage and fixed input frequency and provide an output AC power at a variable voltage and variable frequency. The variable speed drive includes a converter connected to an AC power source providing the input AC voltage. The converter is arranged to convert the input AC voltage to a DC voltage. A DC link is connected to the converter. The DC link is arranged to filter and store the DC voltage from the converter. A first inverter and a second inverter are each connected to the DC link. A motor includes stator windings connected between the first inverter and the second inverter to power the motor by the output AC power from the first inverter and the second inverter. The motor is connectable to a compressor of the chiller system to power the compressor. The motor may be a permanent magnet synchronous motor.

Abstract: A hybrid motor for powering a compressor of a chiller system includes a first rotor portion and a first stator portion configured as a permanent magnet motor and a second rotor portion and a second stator portion configured as a reluctance motor. The second rotor portion includes a reluctance-type rotor, and the second stator portion includes electromagnetic windings capable of inducing a rotary magnetic field. The first rotor portion and the second rotor portion are attached to a common drive shaft. The reluctance motor is arranged to generate start-up torque and initiate rotation of the drive shaft until the drive shaft achieves a predetermined rotational speed. The permanent magnet motor is arranged to power the drive shaft between the predetermined rotational speed and a maximum rotational speed.

Abstract: A drive system for a compressor of a chiller system includes a variable speed drive. The variable speed drive is arranged to receive an input AC voltage at a fixed AC input voltage and provide an output AC power at a variable voltage and variable frequency. The variable speed drive includes a converter connected to an AC power source providing the input AC voltage. The converter is arranged to convert the input AC voltage to a DC voltage. A DC link is connected to the converter. The DC link filters and stores the DC voltage from the converter. An inverter is connected to the DC link. A motor connectable to the compressor for powering the compressor. An active filter connected in parallel with the motor. The active filter is arranged to generate high frequency currents having a magnitude and opposite polarity, with respect to the output AC power of the variable speed drive. The high frequency currents generated by active filter substantially cancel out high frequency currents flowing into the motor.