Therefore, the value of grid impedance [Z.sub.g] can be estimated according to the impedance voltage ratio
of the transformer.
Figure 4(a) shows the efficiency in the circular study area under a fixed voltage ratio
and load, [V.sub.1] : [V.sub.2] = 1 : 5 and [R.sub.L] = 10 [ohm].
The DCC1000 is a DC motor controller that comes equipped with a heatsink and fan, as well as an encoder and voltage ratio
input for motors with position feedback capabilities.
"High voltage ratio
DC-DC converter for fuel-cell applications," IEEE Trans.
The dc-dc converter operation is optimum only when the voltage ratio
of the HVS and LVS is equal to the turn ratio of the transformer.
High voltage ratio
, low voltage stress on the diodes and capacitors, compactness, and high efficiency are the main reasons for this choice [3, 5, 6].
Many topologies have been proposed such as fly-back, boost converter, buck-boost converter, Zeta converter, SPEIC converter, forward topology, push-pull topology, half bridge topology, full bridge topology converter can adjust voltage ratio
. A boost converter consists on some inductor, capacitor and switches which convert DC voltage from one level to another level .
In general, crosstalk (dB) = 20 [log.sub.10] (voltage ratio
In applications where the output voltage to input voltage ratio
is large, the Schottky diode is reversed-biased for the majority of the time.
VSC, Local load and grid parameters Parameter Value [R.sub.l] 30 [ohm] [L.sub.l] 50 mH [R.sub.s] 1 [ohm] [L.sub.s] 10 mH [R.sub.t] 1.5 m[ohm] [L.sub.t] 300 [micro]H VSC rated power 1 MW PWM carrier frequency 3,960 HZ [F.sub.0] 60 HZ VSC terminal voltage 600 V DC voltage 1500 V C 9625 [micro]F Nominal grid Line-Line voltage 13.8 kV (rms) Transformer voltage ratio
0.6/13.8 kV Transformer rated power 1 MW
Alesina and Venturini (1981) theoretically proved that the maximum voltage ratio
, [q.sub.max], is equal to 0.866 for the three-phase MC when using balanced input voltage .