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2.2 KEY ELEMENTS OF THE MACHINE
2.2.1 MPPT-BASED SOLAR CHARGE CONTROLLER
The unit has single/ multi MPPT-based Solar Charge Controllers to convert PV power into usable DC power as per
battery and load requirements. The MPPT charger is buck type convertor such that PV voltage (under all
circumstances) should be higher than the maximum battery voltage. Hence, the series-parallel arrangement of
PV array is very critical for maximum power generation. The number of charge controllers depends on the rating
of the system.
2.2.2 BI-DIRECTIONAL INVERTER
The heart of the system includes an Active-Front-End based Bi-directional inverter which can perform AC-DC as
well as DC-AC conversion and also synchronize with Grid or DG set. The convertor can import/ export power from
Grid/DG depending upon the mode of operation. Its 4-quadrant design ensures highest level of customization to
perform charge/discharge functions.
The Bi-directional convertor can act as an inverter under normal mode of operation such that it converts PV and
Battery power into 240V/ 415V AC 50Hz supply for the connected loads. The same convertor acts as a grid charger
to charge the batteries using grid supply whenever required.
In case of three-phase systems, each phase is capable of delivering one-third power of the total inverter capacity.
All the three phases have been designed for 100% power imbalance i.e., all the 3 phases need not be loaded equally
for operation. This has been guaranteed using 3 independent circuits for the 3 phases and a 12 IGBT design which
is perfect for imbalanced type of applications.
The inverter section has inbuilt galvanic isolation using power transformer of rated capacity which ensures
rugged design under extremely fluctuating and impure grid conditions. It also provides isolation between the DC
and AC sides.
2.2.3 AUTO BYPASS ARRANGEMENT
Auto Bypass Feature is an integrated part of this system such that no extra semi-conductor device is required to
perform this function. Being an Active-Front-End Convertor, there is synchronization between Grid and Inverter
Sine wave with a seamless transfer of power from inverter to grid with less than 5msec of changeover time.
However, Anti-Islanding functionality from Grid has been achieved through an Anti-islanding Switchgear device
as per IEC standards.
2.2.4 DISPLAY KEYPAD UNIT
The Display Keypad Unit (DKU) is the single point of interaction between the user and inverter. It consists of a blue
colored graphical LCD, 8 push buttons and 3 LEDs in the form of stickers. DKU is used for settings change,
parameter display, fault annunciation or any other indication in the machine.
2.2.5 REMOTE MONITORING SYSTEM (OPTIONAL)
HBD-NG range of inverters come with an option of Remote Monitoring System (RMS) depending upon the chosen
model. For any inverter rating, three types of models are available with the suffix C00, C01 or C02, depending upon
the type of communication. C00 model does not have any external communication, C01 comes with inbuilt
MODBUS over RS485 communication, and C02 has GPRS based remote monitoring.
2.3 PRODUCT NOMENCLATURE
HBD-NG range of Smart Storage Solar Inverters has been named using a common nomenclature to avoid any
confusion. Any part number (serial number) includes the capacity of inverter, no. of phases, battery voltage,
charge controller capacity, number of charge controllers, monitoring type as well as the overload capacity.
Please ensure that right from the ordering-stage to installation, reference is made to any unit using the correct
part number. This part number is mentioned on datasheet, quotation, invoice, and also the actual unit post-
dispatch. The warranty claim registration online also involves reference to this part number to avoid any
confusion. A sample part number has been explained below for clarity:
