How Much DC Power Is Necessary?

Abstract

Many proposals for future power systems for warships are extant. Anticipated improvements in capability, operating economy, and signature reduction may not be uniquely associated with these power systems. Alternatives are available for constructing variable speed drives and prime movers for ships with electric drives. These alternatives may open new design possibilities.

Power Converter Sizing for a Switched Doubly Fed Machine Propulsion Drive

“…whereas the normalized electromagnetic torque is governed by (5) and the normalized flux linkage equations are…”

“…Unlike the configuration of shorting the stator, the switched DFM in [5] proposes to use a dc source excitation in lowspeed operating mode. This leads to reduced structural noise at low operating speeds critical for ships intended for naval applications [7], [8].…”

“…For example, [3] reported a drive configuration in which, during low-speed operation, the stator is shorted, whereas during highspeed operation, the stator is connected to an ac source. Similar approaches have been used for developing and conceptualizing variable speed drives (VSDs) for hydroelectric power stations [4], ship propulsion [5], and centrifugal loads [6].…”

“…While [3] apparently used an iterative method to choose a transition speed to minimize the rotor converter size, [5] and [6] used steady-state load torque-speed characteristic to determine the size of the controlled rotor converter. However, there are multiple design variables that need to be considered in order 0093-9994 © 2014 IEEE.…”

Synchronous Machine Model With Voltage-Behind-Reactance Formulation of Stator and Field Windings

“…S YNCHRONOUS machines directly connected to diode rectifiers are commonly used to provide power to dc loads in automotive, aircraft, and marine applications (e.g., [1]- [3], respectively). In such applications, the switching dynamics associated with the machine/rectifier interaction create significant simulation challenges.…”