Integrated multi-port generator-rectifier device and method
An integrated multi-port generator-rectifier device includes multiple passive output ports provided from a plurality of passive-rectifier windings on a common, single magnetic structure. The passive-rectifier windings interact with a plurality of magnetic poles. Coils in the passive rectifier windings are serially connected. Each of the passive rectifier windings has a pitch as that is a fraction of magnet pole pitch and a pattern to magnetically decouple back emf phases of the separate rectifiers. The device further includes an active port provided by an active rectifier.
1. An integrated multi-port generator-rectifier device, comprising:
multiple passive output ports provided from a plurality of passive-rectifier windings on a common, single magnetic structure, wherein the passive-rectifier windings interact with a plurality of magnetic poles, wherein the passive rectifier windings are serially connected, wherein each of the passive rectifier windings comprises a pitch that is a fraction of magnet pole pitch and a pattern to magnetically decouple back emf phases of the separate rectifiers, the device further comprising an active port provided by an active rectifier.
2. The device of claim 1 , wherein the passive-rectifier windings comprise a winding function that consists of two non-zero, bi-polar intervals such that a product of any two winding functions is zero, leading to zero mutual inductance.
3. The device of claim 2 , comprising three six-pulse passive-rectifier windings in a three-phase design, wherein each of the three passive-rectifier windings includes multiple fractional-pole-pitch coils in serial arrangement to create a primary back emf phase of 120° from primary back emf phases of the other two passive-rectifier windings, and to create two phase-shifted secondary back emf phases at a predetermined phase shift from each and from the primary back emf phase.
4. The device of claim 3 , wherein the predetermined phase shift is 60/(k−1),° wherein k=the total number of ports including the passive output ports and the active port.
5. The device of claim 1 , having no DC-side filter capacitors in the passive output ports.
6. The device of claim 1 , wherein coil and pole pitch of the passive-rectifier windings are related by:
nL c =pL p , where n is an integer and p is an even integer number, denoting a number of coils and a number of magnetic poles, respectively, L c and L p are coil pitch and pole pitch, respectively.
7. The device of claim 6 , wherein windings of each of the passive-rectifier windings comprise coils connected in opposite polarity to create the two secondary back emf phases.
8. The device of claim 1 , wherein the active rectifier comprises a winding axially split from the passive-rectifier windings.
9. The device of claim 8 , comprising control to control the active rectifier as a DC current source that draws power dependent on generator rotation speed to achieve maximum power-point tracking.
10. The device of claim 9 , connected between a wind-powered generator and a power grid interface.
11. The device of claim 9 , wherein the control controls a majority of power to be ported through the passive ports.
12. The device of claim 1 , wherein the windings are on a rotor or stator and the magnetic poles are on the other of the rotor or stator.
13. The device of claim 12 , wherein the magnetic poles comprise magnets mounted between retaining rings forming one of the rotor or stator.
14. An integrated multi-port generator-rectifier device, comprising:
a plurality of ports, wherein one of the plurality of ports powers an active rectifier and the remaining power capacitor-less passive rectifiers, wherein the active rectifier is axially split from the passive rectifiers, wherein the passive rectifiers share a common and single magnetic structure comprising a plurality of magnetic poles, wherein each passive rectifier has a three-phase winding set, and each phase is 120-degree phase shifted from the other two, wherein each phase winding in the three-phase winding set comprises serially connected multiple coils, wherein each coil comprises a pitch that equals a fraction of a magnetic-pole pitch of the magnetic poles; wherein a coil connection pattern of the serially connected coils is configured such that each phase winding comprises a zero-average winding function that consists of two non-zero, bi-pole intervals such that any two phases on the passive-port magnetic structure are magnetically decoupled to provide zero mutual inductance.