4
Intelligent MPPT algorithm, the maximum power point tracking is not affected by abrupt change of illumination
Accurate identification technology for power change guarantees accurate and stable static MPPT;
Wide operating temperature range (
– 25 °C ~ + 60 °C),
continuous power generation at full load in high temperature
High reliability
Long lifetime design of film capacitor, 25 years of designed service life for complete machine
Natural heat dissipation, waterproof, dust resistance, salt fog resistance and corrosion resistance
passive islanding protection, grid-connected relay redundancy disconnection protection
Multilayer, step-by-step overcurrent, overvoltage, overtemperature and short-circuit protections for software and
hardware
6 strings fault monitoring with rapid positioning
Advanced control technology
Double modulation of three level SPWM and SVPWM, natural and smooth switchover
Adaptive control, adapting to harsh weak power grids environment
Harmonic current compensation, THD < 1%
Supporting active and reactive power grid dispatch and SVG function at night
LVRT function
User-friendly and flexible
Status display with LED indicators, concise interface
Built-in DC SPD and fuse, no need of DC combiner box, reducing cost for users
DC shut-off circuit breaker for safe and convenient maintenance operating
IP 65 protection level for outdoor use
Wall mounting design, one-step forming of aluminum shell
Standard RS485 / APP / GPRS / Wi-Fi / Bluetooth communications; Optional PLC viewing the system operation
information
2.3 Working
principle
Figure 2 shows the schematic diagram of EA33//40KTLSI inverter. Electric energy generated by PV module passes
through lightning arrester which absorbs surge voltage at DC side, and capacitive energy storage maintains DC
voltage stable. With the application of three-level SPWM and SVPWM dual modulation, three-phase full-bridge
inverter transforms DC power into AC power with the same frequency and phase as power grid, and sine wave AC
power is generated through filter, high-frequency signal conducted interference is restrained by AC filter, then the
electric energy is sent to the power grid.
Fig. 2 Schematic diagram of EA33/40KTLSI inverter
