Traditional PWM vs Morningstar’s TrakStar™ MPPT Technology Morningstar’s MPPT charge controllers use our patented TrakStar advanced control MPPT algorithm to harvest maximum power from a Solar Array’s peak power point. It is generally accepted that even the most basic MPPT controller will provide an additional 10‐15% of charging capability, when compared to a standard PWM regulator.
Traditional PWM vs Morningstar’s TrakStar™ MPPT Technology ••• Traditional PWM vs Morningstar’s TrakStar™ MPPT Technology Introduction: Morningstar MPPT (Maximum Power Point Tracking) charge controllers’ utilize Morningstar’s own patented, advanced TrakStar MPPT technology to harvest the maximum amount of power from the solar array. It is generally accepted that even the most basic MPPT controllers will provide an additional 10‐15% of charging capability compared to a standard PWM regulator.
Traditional PWM vs Morningstar’s TrakStar™ MPPT Technology ••• The Vmp (maximum power voltage) is the voltage where the product of the output current and output voltage (amps * volts) is greatest and output power (watts = amps * volts) is maximized. Module wattage ratings (e.g. 100W, 205W) are based on Pmp (maximum power) at Vmp under standard test conditions (STC). Using a nominal 12V system as an example, the battery voltage will normally be somewhere between 10 – 15 VDC.
Traditional PWM vs Morningstar’s TrakStar™ MPPT Technology ••• TrakStar™ Maximum Power Point Tracking: Morningstar MPPT controllers feature TrakStar technology, designed to quickly and accurately determine the Vmp (maximum power voltage) of the solar array. TrakStar MPPT controllers ‘sweep’ the Staying on Track solar input to determine the voltage at which the array is producing the maximum amount of power.
Traditional PWM vs Morningstar’s TrakStar™ MPPT Technology ••• is precisely the time when batteries will benefit from an increased amount of charging current. Environmental Considerations: Environmental conditions will cause the Vmp of a solar array to fluctuate with partial array shading and module temperature having the most impact. MPPT technology allows the system to track the changing Vmp and maximize energy harvest in any environmental conditions.
Traditional PWM vs Morningstar’s TrakStar™ MPPT Technology ••• Recommended values for Vmp are listed below: 12V systems: Vmp > 15V 24V systems: Vmp > 30V 36V systems: Vmp > 45V 48V systems: Vmp > 60V A PV module’s output current will decrease significantly at voltages higher than Vmp and will be 0 Amps at Voc. Therefore, the temperature compensated Vmp of the array should be higher than full battery voltage to ensure effective charging over the entire battery voltage range.
Traditional PWM vs Morningstar’s TrakStar™ MPPT Technology ••• Array Sizing for MPPT Regulators: As with PWM regulators, the most basic concern when sizing an MPPT solar array is open circuit voltage (Voc). The temperature compensated (see Appendix) Voc of the array must be less than the maximum input voltage rating of the MPPT controller. Higher Voc has the potential to damage the unit.
Traditional PWM vs Morningstar’s TrakStar™ MPPT Technology ••• IMPORTANT: MPPT controllers can be used with off‐grid or grid-tied modules. PWM controllers should only be used with off‐grid modules. Maximizing Efficiency: Morningstar TrakStar™ MPPT controllers will operate at slightly different efficiencies depending upon the nominal battery voltage being used, the Vmp of the array, and the total wattage of the array.
Traditional PWM vs Morningstar’s TrakStar™ MPPT Technology ••• Maximizing MPPT Boost with a Morningstar MPPT Controller: Morningstar’s patented TrakStar MPPT technology sets itself apart from other less effective MPPT solar controllers on the market.
Traditional PWM vs Morningstar’s TrakStar™ MPPT Technology ••• PWM. It would not be economical to use MPPT in such a situation. Average temperature at the site should be a factor considered when making a regulator choice (See Appendix). 3. Systems in which array power output is significantly larger than the power draw of the system loads would indicate that the batteries will spend most of their time at full or near full charge.
Traditional PWM vs Morningstar’s TrakStar™ MPPT Technology ••• Morningstar’s MPPT Controllers: Morningstar presently offers 3 MPPT controllers: SunSaver MPPT™ for small PV systems and two TriStar MPPT™ controllers for larger PV systems, as summarized below: SunSaver MPPT Maximum Battery Current TriStar MPPT 15 amps 45 amps 60 amps 12 volt 200 watts 600 watts 800 watts 24 volt 400 watts 1200 watts 1600 watts none 2400 watts 3200 watts 75 volts 150 volts 150 volts Max.
Traditional PWM vs Morningstar’s TrakStar™ MPPT Technology ••• Wrap-Up: The Solar Charge Controller is the Heart of a Stand-alone PV System.
Traditional PWM vs Morningstar’s TrakStar™ MPPT Technology ••• Self-Diagnostic Capabilities Information – LEDs, Meters, Alarms, Data Acquisition & Communication Ports Temperature Compensation Low Voltage Disconnect (LVD) Battery, PV & Load Status Low Self Consumption Overall Quality (Automated or Hand Production): Operating Life (MTBF & FIT Rates) ISO 900x Certifications: CE, UL, Class 1 Division 2, FCC Class B Part 15, etc… 5 Year Warranty Proven Track Record Ease of Use: Large
Traditional PWM vs Morningstar’s TrakStar™ MPPT Technology ••• Appendix - Temperature Compensation: It is important to take into account temperature compensation and understand how it relates to both the output voltage and output current of a solar module. Solar modules have performance ratings under standard test conditions (STC); normally a cell temperature of 25°C and 1000W/m2 irradiance. Actual operating conditions will, of course, vary from STC.
