SamplexPower Evolution Series Owner's Manual page 58

SECTIOn 4 |
4.1 generAL DeSCriPtion
EVO is a Pure Sine Wave, bi-directional, Single-Phase Inverter / Charger with a Transfer relay
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that operates either as an inverter Or as a smart battery charger. It uses a common Converter
Section that can work in two directions – in one direction it converts external AC power to DC
power to charge the batteries using Grid or Generator (Charging Mode) and in the other direc-
tion, it converts DC power from the battery to AC power (Inverting Mode). This allows the same
power components to be used in both directions resulting in high-energy transfer efficiency with
fewer components. Please note that it can NOT work in both the directions at the same time (i.e.
it cannot work as an inverter and as a charger at the same time).
High performance 100 MHz DSP (Digital Signal Processing) type of micro-controller and Pulse
Width Modulated (PWM) conversion circuits are used for the above implementation.
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:
Up to 2 external AC input power sources – Grid or Generator or both with PrIOrITY for
–
Grid if both Grid and Generator inputs are available at the same time
DC battery Source consisting of 12V/24V battery bank. 4 versions of EVO
–
2 versions for 12 VDC battery input (EVO-2212E and EVO-3012E) & 2 for 24 VDC battery
input (EVO-2224E and EVO-4024E)
Additional external charging source: The output of the external charger of up to 50A
–
capacity is routed through this unit and operates in parallel with the internal charger. The
internal charging current is controlled to ensure that the combined current fed to the battery
does not exceed the programmed bulk Charging 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 230 VAC, 50 Hz / 60 Hz (50 Hz default) 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
The low DC voltage from the DC battery Source is inverted to the AC voltage in two steps. The low
DC voltage from the DC battery Source is first converted to low frequency (50 Hz or 60 Hz ; 50 Hz
default), low voltage synthesized sine wave AC using an H-bridge configuration and high frequency
PWM (Pulse Width Modulation) technique. The low frequency, low voltage synthesized sine wave
is then stepped up to 230 VAC pure sine wave voltage using a low frequency Isolation Transformer
and filtration circuit. This type of DC to AC inversion is called Hybrid Type – a combination of low
frequency and high frequency implementation. Other distinctive features of the Inverter Section are
given below:
Soft Start: The inverter design incorporates "Soft Start" feature with the following advan-
tages and protections:
58 | SAMLEX AMErICA INC.
general Description & Principles of Operations
are available.
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