General Description & Principles Of Operation - Samlexpower Evolution Series Owner's Manual

SECTION 4 |
4.1 GENERAL DESCRIPTION
EVO Series is a Low Frequency Type, Pure Sine Wave, Single Phase Inverter-Charger with a built-in Transfer Relay. It
uses high performance, 100MHz SP (Digital Signal Processing) type of micro-controller and Pulse Width Modulation
(PWM) control. It is Bi-Directional i.e. it uses a common Converter Section consisting of Low Frequency Isolation
Transformer and Mosfet based H-Bridge that can work in two directions as follows:
1) AC to DC Charging Mode: The common Converter Section is used to convert external AC input power to
DC output power to charge the batteries and at the same time, pass through the AC input power to the AC
loads
2) DC to AC Inverting Mode: The common Converter Section is used to convert DC input power from the
batteries to AC output power to feed the AC loads
The above Bi-Directional implementation allows the same power components to be used in both directions
resulting in high- energy transfer efficiency with fewer components and higher reliability
i
INFO
Please note that as the unit is Bi-Directional with a common Converter Section as explained above, it
cannot work as inverter and charger at the same time
4.2 COMPONENTS OF THE SYSTEM
It consists of 3 Sections – Inverter Section, Battery Charger Section and AC Input/Transfer Relay Section. The unit is fed
with the following inputs:
– 120 VAC, 60 Hz, Single Phase AC input
– DC Battery Source consisting of 12V/24V battery bank. - 4 versions of EVO are available. 2 versions for 12 VDC
battery input (EVO-2212F and EVO-1212F-HW) & 2 for 24 VDC battery input (EVO-1224F and EVO-1224F-HW)
– Additional external charging source: Solar Charge Controller of up to 50A capacity. The output of the external
Solar Charge Controller is routed through this unit and operates in parallel with the internal charger. The current
delivered by the external charge controller is measured in real time. The internal charging current is controlled to
ensure that the combined current fed to the battery does not exceed the programmed value of parameter "BULK
CURRENT". This improves the life of the battery. Please see Section 5.4 for more details.
4.3 INVERTER SECTION
The Inverter Section is a heavy-duty, continuous rated, DSP micro-controller based inverter generating a Pure Sine Wave
output of 120 VAC, 60 Hz from the DC Battery Source. It is able to supply AC power to various types of AC loads such
as resistive loads (heaters, incandescent lamps etc) or reactive loads (motors, air conditioners, refrigerators, vacuum
cleaners, fans, pumps, Switched Mode Power Supplies (SMPS) used in audio / video equipment and computers, etc.).
4.3.1 Principle of working of Inverter Section
Low DC voltage from the DC Battery Source is inverted to AC voltage in two steps. Low DC voltage from the DC
Battery Source is first converted to low frequency (60 Hz), low voltage synthesized sine wave AC using Mosfet
76 | SAMLEX AMERICA INC.
General Description & Principles of Operation