Patent application number | Description | Published |
20100080028 | POWER CONVERSION SYSTEM AND METHOD FOR ACTIVE DAMPING OF COMMON MODE RESONANCE - Power conversion systems and methods are presented for damping common mode resonance, in which inverter or rectifier switching control signals are selectively modified according to a damping resistance current value computed using a predetermined virtual damping resistance value in parallel with an output or input capacitor and a measured output or input voltage value to mitigate or reduce common mode resonance in the converter. | 04-01-2010 |
20110057444 | GRID FAULT RIDE-THROUGH FOR CURRENT SOURCE CONVERTER-BASED WIND ENERGY CONVERSION SYSTEMS - Current source converter (CSC) based wind energy power conversion systems (WECS) and methods are presented in which a unified DC link current control scheme is employed to facilitate grid fault ride-through conditions, with a multiple-mode converter control system that combines the power flow control capabilities of the generator-side and grid-side converters, in which transitions between normal operation and fault condition are achieved automatically by monitoring the grid voltage without the need for, or with partial additional ride-through components. | 03-10-2011 |
20110292696 | VARIABLE FREQUENCY DRIVE AND METHODS FOR FILTER CAPACITOR FAULT DETECTION - Variable frequency motor drives and control techniques are presented in which filter capacitor faults are detected by measuring filter neutral node current and/or voltages and detecting changes in the fundamental frequency component of the measured neutral condition at the fundamental frequency of the input power and/or based on input current unbalance. | 12-01-2011 |
20110299308 | COMMON MODE VOLTAGE REDUCTION APPARATUS AND METHOD FOR CURRENT SOURCE CONVERTER BASED DRIVE - Current source converter drives and common mode voltage reduction techniques are presented in which a space vector modulation zero vector for current source inverter (or rectifier) control is selected according to the switching state of the current source rectifier (or inverter) and according to the AC input power and the AC output power to control the output common mode voltage. | 12-08-2011 |
20120081058 | DC POWER FOR SGCT DEVICES USING A HIGH FREQUENCY CURRENT LOOP WITH MULTIPLE CURRENT TRANSFORMERS - Motor drives and switch driver power systems are presented in which high frequency AC current (I | 04-05-2012 |
20120081061 | ADAPTIVE HARMONIC REDUCTION APPARATUS AND METHODS - Power conversion systems with active front end converters for example motor drives and power generation systems for distributed energy sources are presented with adaptive harmonic minimization for grid-tie converters for minimized or reduced total harmonic distortion in the line current spectrum including the source harmonic current and the grid-tie converter injected current spectrum referred to the line side. | 04-05-2012 |
20120271572 | VARIABLE FREQUENCY DRIVE AND METHODS FOR FILTER CAPACITOR FAULT DETECTION - Variable frequency motor drives and control techniques are presented in which filter capacitor faults are detected by measuring filter neutral node currents and/or voltages and detecting changes in a frequency component of the measured neutral condition and/or based on input current unbalance. | 10-25-2012 |
20130033907 | ADAPTIVE HARMONIC REDUCTION APPARATUS AND METHODS - Power conversion systems with active front end converters for example motor drives and power generation systems for distributed energy sources are presented with adaptive harmonic minimization for grid-tie converters for minimized or reduced total harmonic distortion in the line current spectrum including the source harmonic current, the load harmonics and the PWM harmonics. | 02-07-2013 |
20130057297 | METHOD AND APPARATUS FOR DETECTING POWER CONVERTER CAPACITOR DEGRADATION USING NEGATIVE SEQUENCE CURRENTS - Power converters and control techniques are presented in which capacitor degradation is detected according to negative sequence current by computing an uncompensated negative sequence current and a negative sequence voltage, compensating the negative sequence current based on the negative sequence voltage, comparing the compensated or uncompensated negative sequence current with an automatically calculated threshold and selectively identifying suspected degradation of one or more capacitors if the compensated negative sequence current exceeds the threshold value. The method can be used for power converters, control devices or protection relays for shunt capacitors or filters used in power systems. | 03-07-2013 |
20130242623 | POWER CONVERTER AND INTEGRATED DC CHOKE THEREFOR - A power conversion system with multiple parallel connected motor drives including a plurality of rectifiers and a corresponding inverters connected by windings of a single common mode choke. | 09-19-2013 |
20130286704 | CASCADED H-BRIDGE (CHB) INVERTER LEVEL SHIFT PWM WITH ROTATION - Cascade H-Bridge inverters and carrier-based level shift pulse width modulation techniques are presented for generating inverter stage switching control signals, in which carrier waveform levels are selectively shifted to control THD and to mitigate power distribution imbalances within multilevel inverter elements. | 10-31-2013 |
20140036557 | CASCADED H-BRIDGE (CHB) INVERTER LEVEL SHIFT PWM WITH ROTATION - Cascade H-Bridge inverters and carrier-based level shift pulse width modulation techniques are presented for generating inverter stage switching control signals, in which carrier waveform levels are selectively shifted to control THD and to mitigate power distribution imbalances within multilevel inverter elements using either complementary carrier or complementary reference modulation techniques. | 02-06-2014 |
20140042817 | METHOD AND APPARATUS FOR BYPASSING CASCADED H-BRIDGE (CHB) POWER CELLS AND POWER SUB CELL FOR MULTILEVEL INVERTER - Bypassing methods and apparatus are presented along with power cells and sub cells for multilevel inverters in which DC current flow into a DC link capacitance is interrupted and a bypass switch is closed across a power cell or sub cell output to selectively bypass a power stage of a multilevel inverter. | 02-13-2014 |