| Patent application number | Description | Published |
|---|
| 20080278109 | System and Method for Controlling Input Line Harmonics in a Motor Drive - A motor drive system is disclosed that includes a power input configured to receive alternating current (AC) power and a rectifier having a switching frequency selected to convert the AC power to direct current (DC) power. The motor drive unit also includes an input filter circuit connected between the power input and the rectifier and configured to suppress frequency harmonics across a range of harmonics. Additionally the motor drive unit includes a block filter circuit connected between the power input and the rectifier and configured to substantially block frequency harmonics associated with the switching frequency of the rectifier. Furthermore, the motor drive unit includes an inverter configured to receive the DC power from the rectifier and convert the DC power to a series of pulses configured to drive a motor. | 11-13-2008 |
| 20090058350 | JUNCTION TEMPERATURE REDUCTION FOR THREE PHASE INVERTERS MODULES - Provided is a motor controller and method of controlling a motor with an improved maximum junction temperature rating. In accordance with one aspect of the present invention, a motor is controlled by varying a common mode voltage duty ratio for a plurality of solid state switching devices in a power inverter, generating drive signals for the solid state switching devices based at least in part upon the common mode voltage duty ratio, and changing states of the solid state switching devices based upon the drive signals. | 03-05-2009 |
| 20090251081 | ELECTRIC MOTOR DRIVE EMPLOYING HYBRID, HYSTERETIC/PULSE-WIDTH-MODULATED DYNAMIC BRAKING - A dynamic braking circuit for an electronic motor drive shunts the DC link of the drive with a resistor using two control strategies. The first control strategy used for lower levels of braking employs a pulse width modulated signal and the second control strategy used for higher levels of braking uses a hysteretic signal significantly reducing switching losses in the semiconductor devices controlling the dynamic braking resistor allowing higher braking capacity. | 10-08-2009 |
| 20090276165 | POWER MODULE LIFE ESTIMATION FATIGUE FUNCTION - A system and method for estimating a condition of a power module is provided. In accordance with an embodiment, a motor controller may be maintained by tracking a total proportion of power module life expended by a power module in a variable frequency motor controller based on a minimum junction temperature or a mean junction temperature and a junction temperature change, and indicating when the power module is estimated to fail. | 11-05-2009 |
| 20100078998 | POWER ELECTRONIC MODULE PRE-CHARGE SYSTEM AND METHOD - A power electronics device with an improved pre-charge circuit configuration is provided. More specifically, the input of the motor drive module may accept an AC or DC source voltage. In this way, the pre-charge circuit of the motor drive module may be utilized whether the motor drive is coupled to an AC or DC source. | 04-01-2010 |
| 20100079230 | POWER ELECTRONIC MODULE WITH AN IMPROVED CHOKE AND METHODS OF MAKING SAME - An improved choke assembly for a power electronics device is provided. More specifically, a choke assembly with improved protection from environmental conditions such as dirt and water is provided. An improved choke assembly may include an insulative housing for an inductor coil that seals the inductor coil from the environment. | 04-01-2010 |
| 20100080024 | POWER ELECTRONIC MODULE IGBT PROTECTION METHOD AND SYSTEM - A power electronics device with an improved IGBT protection mechanism is provided. More specifically, systems and methods are provided for reducing the switching frequency of an inverter module based on the junction temperature variation of the IGBT. | 04-01-2010 |
| 20100177452 | DC BUS CLAMP CIRCUIT TO PREVENT OVER VOLTAGE FAILURE OF ADJUSTABLE SPEED DRIVES - The present invention relates to a protective circuit to provide over voltage protection for an ASD. The protective circuit provides the benefits of fewer components with lower power ratings than existing protective circuits. The protective circuit may be incorporated directly in the ASD for continuous protection or mounted externally and connected to the ASD under operating conditions that require the circuit. This flexibility for mounting the protective circuit allows the capacitor of the protective circuit to be sized either in relation to capacitive elements on the DC bus within the ASD or according to external capacitance observed at the output of the ASD. In addition, the circuit is only operative during an overvoltage condition allowing for power ratings lower than would be required for continuous operation. | 07-15-2010 |
| 20110101897 | DC BUS BOOST METHOD AND SYSTEM FOR REGENERATIVE BRAKE - Embodiments of the present invention provide novel techniques for using a switched converter to provide for three-phase alternating current (AC) rectification, regenerative braking, and direct current (DC) voltage boosting. In particular, one of the three legs of the switched converter is controlled with a set of pulse width modulation (PWM) control signals so that the input AC phase having the highest voltage is rectified and one of the switches in the two other legs is turned on to allow for added voltage. This switching activity allows for voltage from multiple AC line mains to be combined, resulting in an overall boost of the DC voltage of the rectifier. The DC voltage boost can then be applied to the common DC bus in order to ameliorate voltage sags, help with motor starts, and increase the ride-through capability of the motor. | 05-05-2011 |
| 20110103096 | THIRTY-SIX PULSE POWER TRANSFORMER AND POWER CONVERTER INCORPORATING SAME - Embodiments of the present invention provide novel techniques for using multiple 18-pulse rectifier circuits in parallel. In particular, each rectifier circuit may include an autotransformer having 15 inductors coupled in series, joined by 15 nodes interposed between pairs of the inductors. The inductors may be represented as a hexagon in which alternating sides of the hexagon have two and three inductors, respectively. Each rectifier circuit may also include three inputs for three-phase AC power coupled to alternating vertices of the hexagonal representation and nine outputs for AC power coupled between each node that is not a vertex of the hexagonal representation and a respective diode bridge. Outputs of the diode bridges for the rectifier circuits may be coupled to a DC bus. In addition, a means for reducing circulating current between the parallel rectifier circuits and for promoting load sharing between the parallel rectifier circuits is also provided. | 05-05-2011 |
| 20110103105 | POWER TRANSFORMER AND POWER CONVERTER INCORPORATING SAME - Embodiments of the present invention provide novel techniques for using multiple 18-pulse rectifier circuits in parallel. In particular, each rectifier circuit may include an autotransformer having 15 inductors coupled in series, joined by 15 nodes interposed between pairs of the inductors. The inductors may be represented as a hexagon in which alternating sides of the hexagon have two and three inductors, respectively. Each rectifier circuit may also include three inputs for three-phase AC power coupled to alternating vertices of the hexagonal representation and nine outputs for AC power coupled between each node that is not a vertex of the hexagonal representation and a respective diode bridge. Outputs of the diode bridges for the rectifier circuits may be coupled to a DC bus. In addition, a means for reducing circulating current between the parallel rectifier circuits and for promoting load sharing between the parallel rectifier circuits is also provided. | 05-05-2011 |
| 20110153234 | GROUND FAULT DETECTION SYSTEM AND METHOD - A ground fault detection system is provided. The ground fault detection system includes a magnetic core having first and second primary legs and a secondary leg disposed between the first and second primary legs. The ground fault detection system also includes first and second primary windings disposed around the first and second primary legs respectively and configured to introduce current in the first and second primary legs. Further, the ground fault detection system includes first and second secondary windings disposed around the first and second primary legs respectively and configured to detect a ground fault based upon a magnetic flux generated in response to the introduced current. | 06-23-2011 |
