Selection and installation considerations of inverters for household distributed PV systems

Usually, after people choose to buy home PV panels, they need to match a series of accessories to the purchased PV panels. And the inverter is a very important part of the PV system, which maintains the effective operation and power generation of the PV system. This article provides some advice on the selection and installation of inverters.

Photovoltaic inverter is a kind of electrical equipment that converts solar energy into electricity, and the public usually chooses outdoor type. This type of inverter usually adopts natural cooling method, using air flow to dissipate heat, and does not need an additional cooling system. It has a high housing protection level (usually needs to reach IP65), requires little environmental modification for installation, and is less costly. Also, since the inverter is installed outdoors, the noise generated by the inverter operation will have a much lower impact on the user, but requires good equipment protection. It is worth mentioning that the noise index of the inverter is not higher than 65 decibels, which will not produce noise hazards.
To learn more about inverter brands, you can read this article published by Maysun in the past: Top 10 Global Inverter Manufacturers in 2022

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Generally, according to the requirements of the system configuration of the corresponding power section of the inverter, the inverter power selected should match the maximum power of the PV cell array, generally selected PV inverter rated output power is similar to the total input power, (usually over-matching control within 1.3), so as to save costs.

The selection of inverter capacity size can be optimized according to the installation conditions. If the installation site is not clear at the early stage of design and not fully considered, you should choose a small power PV inverter as much as possible to achieve multiple independent power tracking, and if necessary, choose a micro-inverter to achieve the maximum power tracking of smaller units, so as to protect the later problems such as series-parallel mismatch caused by the site is not big enough or not regular enough.

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MPPT controller
In the household distributed PV system, due to the limitation of the roof, when the type of PV square, installation orientation and installation inclination are different, or when some modules are shaded at certain time periods, it is appropriate to choose PV inverters with multiple independent MPPT control function, which can configure the system more flexibly, reduce the potential system efficiency loss and power generation loss, improve power generation efficiency, and obtain the maximum power generation revenue for users.

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What should I pay attention to when installing the inverter of PV system?

As the core component of a PV system, the inverter directly affects the system's power generation capacity, and the following points should be noted.

(1) As the connection between the inverter and the grid changes the impedance characteristics of the inverter, it is easy to cause resonance of the inverter itself, which mostly occurs when multiple inverters are connected in parallel.
(2) The inverter must be reviewed by a person after installation, and marked and recorded.
(3) The connection between the inverter ventilation duct and the external duct should be softly connected to prevent mechanical noise caused by mechanical vibration.
(4) When the noise of the inverter increases and there is an odor, draw attention to it, check the internal fault of the inverter, and find out the cause and deal with it as appropriate.
(5) Pay attention to the detection of inverter leakage, grounding, phase sequence, etc. during installation and commissioning.
(6) At least two people should be present at the same time when the inverter is commissioned, and pay attention to the safety protection of the operator.

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The combination of high quality inverter and high performance photovoltaic panels can build an excellent household distributed PV system for you, making your life greener, more efficient and more convenient.

MaysunSolar, as a PV module manufacturer with 15 years of professional experience, can provide you with high quality solar panels and PV system building experience, click the button below to contact us for product quotation.