INVERT YOUR THINKING: THE DUMMIES GUIDE ON USING A SOLAR INVERTER
Find Out What Goes on Inside the Box!
One of the most incredible things about photovoltaic power is its simplicity. Compared to other sources of energy humankind has harnessed to make electricity, PV is the most scalable and modular. Larger PV systems require more electrical bussing, fusing and wiring, but the most complex component between the solar array and the load is the electronic component that converts and processes the electricity: the inverter.
What Does a Solar Inverter Do?
What a solar inverter does is it cost-effectively converts the direct current which is generated by solar panels into high-quality alternating current that can be fed into a power network. A solar inverter incorporates several powerful features and benefits that make the series the most efficient, productive, compact and easy to use.
How a Solar Inverter Works?
In the case of grid-tied PV, the inverter is the only piece of electronics needed between the array and the grid. Off-grid PV applications use an additional ac to dc converter between the array and batteries and a solar inverter with a built-in charger. In this article, we discuss how a solar inverter works, including string, or single-phase, and central, 3-phase inverters. We explore major inverter functions, key components, designs, controls, protections and communication, and theorize about future inverter technology. If you don’t connect anything and just leave the wires dangling, the current has nowhere to go, electrons pile up on one side of the cell, and the voltage across the cell increases until it reaches the built-in voltage.
Solar Pumping Inverter
Advanced solar pumping inverters convert DC voltage from the solar array into AC voltage to drive submersible pumps directly without the need for batteries or other energy storage devices. By utilizing MPPT (maximum power point tracking), solar pumping inverters regulate output frequency to control the speed of the pumps in order to save pump motors from damage.
Solar Inverter (Grid-Tied)
Solar grid-tie inverters are designed to quickly disconnect from the grid if the utility grid goes down. This is an NEC requirement that ensures that in the event of a blackout, the grid tie inverter will shut down to prevent the energy it produces from harming any line workers who are sent to fix the power grid.
Grid-tie inverters that are available on the market today use a number of different technologies. The inverters may use the newer high-frequency transformers, conventional low-frequency transformers, or no transformer. Instead of converting direct current directly to 120 or 240 volts AC, high-frequency transformers employ a computerized multi-step process that involves converting the power to high-frequency AC and then back to DC and then to the final
AC output voltage.
Benefits of Using a Solar Inverter
The following are some of the benefits of using a solar inverter.
One of the basic jobs of a solar inverter is of optimizing efficiency, or reducing loss, which is an important part of inverter design and component selection. The goal is to optimize the inverter for maximum efficiency, while maintaining high reliability and delivering a product at a good price.
When talking about the thermal performance of a solar inverter, the first goal of inverter design is to minimise loss. The next goal is to minimise temperature gain for maximum inverter component life. The last step is to minimise power requirements and energy consumed for cooling system needs.
Monitoring Software of a Solar Inverter:
- In order to reliably control a solar inverter, the software designed to run on the inverter’s digital signal processor or microcontroller is developed over years of code writing and debugging.
- The most critical control is the one driving the power stage. This creates the PWM waveforms that generate the sine waves ending up on the utility grid and at the building’s loads. Software also controls the inverter’s interaction with the grid and drives all the appropriate UL 1741 and IEEE 1547 required controls and events.
- The software controls the MPPT function that varies the dc voltage and current level as required to accurately and quickly follow the moving MPP of the PV array.
- The software is used to drive the contactor that places the solar inverter on the grid in the morning and off the grid at night. Software controls temperature limits and optimizes cooling system controls. Software, its development history and robustness, is a critical element in any inverter.
- Use the control panel to check the event logs from the Events Menu. The menu shows the most recent events as faults or other events. Note that a single fault can potentially give rise to several events. Events are stored in the memory until the event memory is full. When the event memory is full the solar inverter automatically removes the oldest events from the event memory.
- Make sure that the solar inverter is still in its intended operating environment. To do this check the installation environment is still clean, dry, and free of obstacles near to the inverter and that the ambient temperature has not risen since its installation.
Highlights of a Solar Inverter
- High total efficiency
- Built-in and monitored system protection devices
- High maximum input voltage
- Wide DC input voltage range
- Detachable control unit with graphical display
- Integrated performance data monitoring
- Outdoor IP55 enclosure with additional safety features
- Grid support functions
Just to add a few more points at the end. Firstly, the solar inverter sleeps when there is not enough daylight to operate. And lastly, as the sun rises, the solar inverter enters standby mode, and prepares to feed power to the grid. The solar inverter enters to standby mode also by night-time if control unit buttons are activated.