This paper presents a hybrid cascaded H-bridge multilevel motor drive control scheme for electric/hybrid electric vehicles where each phase of a three-phase cascaded multilevel converter can be implemented using only a single DC source and capacitors for the other DC sources. Traditionally, each phase of a three-phase cascaded multilevel converter requires n DC sources for 2n + 1 output voltage...

The Weibull distribution has been previously applied to the mechanical and dieiectric failures of ceramics. In this paper, it is confirmed by experiment that this data treatment method is also valid for application in the dielectric failure of multilayer ceramic capacitors (MLCs) which have undergone screening. The Weibull modulus is found to be a useful parameter indicating the sharpness of th...

This paper proposes a new N-multilevel topologies for T-type inverter. The proposed topologies constitute the single bridge legs with the shape of the rotated character “T” and a variable direct current-link circuit. The proposed topologies present higher efficiency and lower number of components compared with NPC topologies and nested multilevel topologies. Also, other topologies have been com...

We discuss the stability of an adiabatic stepwise-charging circuit with advanced series capacitors, which is effective for the reduction of the applied voltage to each capacitor. SPICE simulation shows that this circuit is stable even if the initial voltages are lower than zero. For the analytical discussion, we derive a matrix that connects charge and voltage in the circuit and show that the m...

A new quadrature oscillator circuit using a single differential voltage current conveyor transconductance amplifier (DVCCTA) and four all grounded passive elements is presented. The proposed circuit provides two current quadrature outputs at high impedance and three voltage quadrature outputs simultaneously. The oscillation condition and oscillation frequency are independently controllable. The...

Scintillations in solid tantalum capacitors are momentarily local breakdowns terminated by a self-healing or conversion to a high-resistive state of the manganese oxide cathode. This conversion effectively caps the defective area of the tantalum pentoxide dielectric and prevents short-circuit failures. Typically, this type of breakdown has no immediate catastrophic consequences and is often con...

Improving the reactive power and voltage profile of a distribution substation is investigated in this paper. The purpose is to properly determination of the shunt capacitors on/off status and suitable tap changer (TC) position of a substation transformer. In addition, the limitation of secondary bus voltage, the maximum allowable number of switching operation in a day for on load tap changer an...

A distribution system is an interface between the bulk power system and the consumers. Among these systems, radial distributions system is popular because of low cost and simple design. In distribution systems, the voltages at buses reduces when moved away from the substation, also the losses are high. The reason for decrease in voltage and high losses is the insufficient amount of reactive pow...

A neurocomputer based on a high-density analog integrated circuit developed in a 3 mum CMOS technology has been built. The 1.6 mmx2.4 mm chip contains 18 neurons and 161 synapses in three layers, and provides 16 inputs and 4 outputs. The weights are stored on storage capacitors of the synapses. A formalization of the error back-propagation algorithm which allows the use of very small nonlinear ...

A balanced transconductance-C biquad implemented in the digital subset of a 0.9-um CMOS process operates at frequencies up to 450 MHz and Q factors from a nominal value near 1 to approximately 100 with 30-40-dB dynamic range. By switching in capacitors and adjusting control voltages it can be tuned to below 30 MHz, demonstrating the capability of operating over the entire VHF range. Active area...