TS-MPPT-600V-48 Wind charging control Info

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including the size and health (age) of the batteries, larger loads which could reduce the voltage during charging or
loads which have lower LVD settings. These factors should be taken into account to determine the minimum battery
voltage and minimum operating input power for the system.
Turbine Requirements of the TriStar MPPT controllers
Ideally, the wind or hydro turbine will be able to operate within the operating limits for input Voltage and Power as
shown in the proceeding section. For some wind turbines, peak power levels may exceed the maximum operating
power of the controller with very strong wind gusts.
Power
The turbine will need to operate within the DC Voltage and Power limits from the proceeding section.
If the Max Power from the Turbine can exceed the lowest expected maximum input power (during lowest battery
voltage) of the TriStar MPPT controller it may be necessary to implement some type of power reduction either
mechanically or with a dump load on the input side of the TriStar MPPT controller.
● An AC Clipper is preferred since the diodes in the rectifier prevent reverse current.
● DC Diversion loads should only be implemented with a diode to prevent reverse current.
● If the mechanical response time (furling etc.) is not fast enough it may be possible to use an auto-disconnect
switch to prevent overpower and overvoltages.
High Voltage
The derate curves shown in the high voltage range indicates the maximum operating voltages that might be
considered. For a full power system that is expected to operate at the controller’s full rated current the maximum
operating current should stay below the point where the output current could start to derate. Derating might start as
low as 115V for the TriStar MPPT (150V) and 460V for a TriStar MPPT 600V (Vb min. = 48V).
High voltage limit clipper/diversion load switches can be used with dump loads to prevent freewheeling of the
turbine which can prevent higher voltages during high wind speeds. These devices can operate so that the TriStar
MPPT can continue to operate in the full power voltage range without derating. Many turbines also have mechanical
loading or furling sometimes based on rotational speed rather than input voltages. The likelihood that the electrical
or mechanical braking will slow down the controller before the voltage increases into derated power or a full
shutdown of the controller will depend on the response time and the voltage or rotational speed settings. Gust levels
and turbulence at the site can also play a role in how fast the wild DC voltage and power can change. Other
mechanical and/or electrical factors can also affect the maximum possible voltage during the activation of the clipper
or mechanical braking.
Overvoltage Protection
The electrical load is like a braking system for the turbine. It is critical that the electrical load is maintained
continuously especially if there is no auto-furling or other mechanical braking system. High Voltage Clipping, or
Diversion Load Switching on the input, is often used with small wind systems even those with mechanical braking
systems to keep the rotational speed of the turbine under control during extremely strong gusts or at times when the
power electronics (inverter or MPPT controller) shuts down.
Clipper/diversion loads must be used on the AC circuit before the rectifier rather than on the DC circuit after the
rectifier unless a Diode is used at the input of the MPPT controller to prevent the possibility of any reverse current.
As with solar PV systems the maximum input voltage must never exceed the max. input voltage rating for the TriStar
MPPT controllers (150V or 600V) under all circumstances. The worst-case scenario would be if the controller shuts