Abstract: A gate driver for power semiconductors is disclosed. The gate driver includes modulation to modulate signals from a controller to a radio frequency (RF) range that is much higher than frequencies associated with conducted EMI. The gate driver also includes RF transformer and tank circuit to that couples the modulated signals, filters EMI, and provides galvanic isolation. The gate driver further includes a RF demodulator and unfolder circuit for converting the RF signal into a signal appropriate for controlling the gate of a power semiconductor for switching. Additionally, the disclosed gate driver provides active gate control using programmable waveforms with values that can range over a continuous range of voltages.

Abstract: A gate driver for power semiconductors is disclosed. The gate driver includes modulation to modulate signals from a controller to a radio frequency (RF) range that is much higher than frequencies associated with conducted EMI. The gate driver also includes RF transformer and tank circuit to that couples the modulated signals, filters EMI, and provides galvanic isolation. The gate driver further includes a RF demodulator and unfolder circuit for converting the RF signal into a signal appropriate for controlling the gate of a power semiconductor for switching. Additionally, the disclosed gate driver provides active gate control using programmable waveforms with values that can range over a continuous range of voltages.

Abstract: Disclosed is a phase-shifted square wave modulation technique for single-phase and three-phase IM2DC applications in HVDC/MVDC systems. A square wave based modulation waveform is applied to each cell of IM2DC and compared to the phase-shifted carrier waveforms to generate device gate signals. As a result, a higher equivalent switching frequency can be achieved, and square wave based arm and AC link waveforms will be generated. In addition, power flow of IM2DC can be controlled by a phase shift angle of the square modulation waveforms between HVS and LVS. The converter cell capacitors can be reduced in size because they are only required to smooth high switching frequency ripple components. In addition, lower TDR can be achieved due to the higher power transferring capability of square waves.

Abstract: Disclosed is a phase-shifted square wave modulation technique for single-phase and three-phase IM2DC applications in HVDC/MVDC systems. A square wave based modulation waveform is applied to each cell of IM2DC and compared to the phase-shifted carrier waveforms to generate device gate signals. As a result, a higher equivalent switching frequency can be achieved, and square wave based arm and AC link waveforms will be generated. In addition, power flow of IM2DC can be controlled by a phase shift angle of the square modulation waveforms between HVS and LVS. The converter cell capacitors can be reduced in size because they are only required to smooth high switching frequency ripple components. In addition, lower TDR can be achieved due to the higher power transferring capability of square waves.

Abstract: This invention presents a family of isolated BESS topologies with multiple functions, which are suitable for high voltage and high power DC grid application. A battery energy storage system (BESS) for direct current (DC) grid applications is provided, including an alternating current (AC) transformer having a primary side and a secondary side, at least one primary side arm coupled to the primary side of the AC transformer, the at least one primary side arm comprising a plurality of cascade connected voltage source converter sub-modules and a plurality of energy storage battery units and at least one secondary side arm coupled between the secondary side of the AC transformer and a DC grid voltage bus, the at least one secondary side arm comprising a plurality of cascade connected voltage source converter sub-modules. Modulation and control strategies for the various topologies are also provided.

Abstract: A self-balanced modulation method and a closed-loop magnetic flux rebalancing control method for parallel multilevel inverters. The combination of the two methods provides for balancing of the magnetic flux of the inter-cell transformers (ICTs) of the parallel multilevel inverters without deteriorating the quality of the output voltage. In various embodiments a parallel multi-level inverter modulator is provide including a multi-channel comparator to generate a multiplexed digitized ideal waveform for a parallel multi-level inverter and a finite state machine (FSM) module coupled to the parallel multi-channel comparator, the FSM module to receive the multiplexed digitized ideal waveform and to generate a pulse width modulated gate-drive signal for each switching device of the parallel multi-level inverter. The system and method provides for optimization of the output voltage spectrum without influence the magnetic balancing.

Abstract: A self-balanced modulation method and a closed-loop magnetic flux rebalancing control method for parallel multilevel inverters. The combination of the two methods provides for balancing of the magnetic flux of the inter-cell transformers (ICTs) of the parallel multilevel inverters without deteriorating the quality of the output voltage. In various embodiments a parallel multi-level inverter modulator is provide including a multi-channel comparator to generate a multiplexed digitized ideal waveform for a parallel multi-level inverter and a finite state machine (FSM) module coupled to the parallel multi-channel comparator, the FSM module to receive the multiplexed digitized ideal waveform and to generate a pulse width modulated gate-drive signal for each switching device of the parallel multi-level inverter. The system and method provides for optimization of the output voltage spectrum without influence the magnetic balancing.