In fact, since a dc regulator will normally be required after the filter anyway, the total component count is almost the same as for the resistor emulation method, in which the filter is effectively incorporated into the regulator. For a high-frequency line input, on the order of 20 kHz, the simple LC cannot be discarded so peremptorily, since the inductor size can be compared with that for the resistor emulation method. Other methods require complicated switch drive algorithms to construct the input current waveshape. The next simplest method is the resistor emulation approach in which the inductor size is determined by the converter switching frequency and not by the line input frequency. The simplest method is the LC filter following the rectifier. Several methods of shaping the input current waveform in ac-to-dc converters were reviewed. Input frequencies much higher than normal, up to 20 kHz were emphasized. Input current shaping techniques for ac-to-dc converters were investigated. However, the device poses several advantages, i.e., low conduction drop and low cost. Asymmetrical SCR is basically a SCR device and needs commutation circuit for turn off. For other electric vehicle (EV) related applications such as battery charger circuit, however, MOSFET is advantageous to other devices because of drive circuit simplicity and high frequency capability. For the main drive of an electric vehicle, device paralleling is normally needed to achieve practical power level. For the 400 V device, the current rating is limited to 25 A. Power MOSFETs, on the other hand, are much smaller in current rating. These devices are currently used as key switching elements inverters for ac motor drive applications. The Bipolar transistors, including discrete device and Darlington devices, range from 100 A to 400 A and from 400 V to 900 V. Three types of power devices are evaluated in the effort: high power bipolar or Darlington transistors, power MOSFETs, and asymmetric silicon control rectifiers (ASCR). The results of evaluation of power semiconductor devices for electric hybrid vehicle ac drive applications are summarized. Also, another pixel circuit is proposed to further reduce the driving current to meet the current constraints for the OLED-on-silicon.Įvaluation of semiconductor devices for Electric and Hybrid Vehicle (EHV) ac-drive applications, volume 1 Simulation results indicate that the proposed circuit is less sensitive to switching effects. This paper proposes a novel pixel circuit consisting of three transistors and one capacitor to realize AC driving for the OLED-on-silicon while restraining the switching effects. That would decrease the gray scale of the OLED. The AC driving scheme for OLEDs, which uses the pixel circuit with two transistors and one capacitor (2T1C), can extend the lifetime of the active matrix organic light-emitting diode (AMOLED) on silicon, but there are switching effects during the switch of AC signals, which result in the voltage variation on the storage capacitor and cause the current glitch in OLED. Liu, Yan-Yan Geng, Wei-Dong Dai, Yong-Ping Restraining for switching effects in an AC driving pixel circuit of the OLED-on-silicon The control system generates a command signal to cause the PWM converter to control an output of the AC motor drive corresponding to an input to the AC motor, selectively generates a modified command signal to cause the PWM converter to inject a DC signal into the output of the AC motor drive, and determines a stator winding resistance of the AC motor based on the DC signal of at least one of the voltage and current.

The system includes an AC motor drive having an input connectable to an AC source and an output connectable to an input terminal of an AC motor, a pulse width modulation (PWM) converter having switches therein to control current flow and terminal voltages in the AC motor, and a control system connected to the PWM converter. Lu, Bin Habetler, Thomas G Zhang, PinjiaĪ system and method for determining the stator winding resistance of AC motors is provided. System and method for determining stator winding resistance in an AC motor using motor drives

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