Introduction
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Operation Features
The PV225S 225 kW Grid-Tied Photovoltaic Inverter is a UL 1741 listed, utility
interactive, three-phase power conver sion system for grid-connected photovolt aic
arrays with a power rating of 225 kW. Designed to be easy to inst all and operate,
the PV225S automates start-up, shutdown, and fault detection sc enarios. With
user-definable power tracking that matches t he inverter to the array and adjustable
delay periods, users are able to customi ze startup and shutdown sequences.
Multiple PV225S inverters are easily paralleled for larger power installations.
The PV225S power conversion system consists of a pulse-width modulated
(PWM) inverter, switch gear for isolation and prote ction of the connected AC and
DC power sources, and a high efficiency custom Wye:Wye isolati on transformer.
Housed in a rugged NEMA-3R rated, powder-coated steel enclosure, the PV225S
incorporates sophisticated Intellimod® (IPM) Insulated Gate Bipolar Transistors
(IGBT’s) as the main power switching devices. An advanced, field- proven,
Maximum Peak Power Tracker (MPPT) integrated within the PV225S control
firmware ensures the optimum power throug hput for harvesting energy from the
photovoltaic array.
The advanced design of the PV225S includes an EMI output filter and the mai n
AC contactor located electrically on the utility side of the isolation transformer.
The location of the main AC contactor, and the ability to de-energize the isolation
transformer during times of non-operatio n, greatly reduces the night-time tare
losses consumed by an idle isolation transformer. An integrated soft-start circuit
precludes nuisance utility-tie circuit brea ker trips as the result of isolation
transformer inrush current.
Additionally, the PV225S integrated controller contains self-prot ection features
including over and under voltage and frequency safe guards. An integral
anti-island protection scheme prevents the inve rter from feeding power to the grid
in the event of a utility outage.
The PV225S includes a local user interface comprised of an ON/OFF switch,
keypad, and 4-line, 80 character LCD display. A user-friendly Gra phic User
Interface (GUI) provides a remote inte rface for operator interrogation of PV225S
system status, control, metering/data logging and protective functions within the
PV225S. The status, control, and logging features are also supported by the choice
of three communication mediums, allowi ng the information to be accessed or
commanded remotely.

Fixed Unity Power Factor Operation

The Xantrex PV Series of grid-tied inverters maint ains unity power factor during
operation. The control software constantly senses utility voltage, and constructs
the output current waveform to match the utility voltage. The PV line of inverters
is not capable of operation without the presence of no rmal utility voltage, nor is it
capable of varying the output power factor off unity.