With the increasing popularity of household energy storage systems（RESS）, many families have begun to install photovoltaic systems with energy storage batteries. However, they are often confused about the selection and configuration of inverter power, battery capacity, and photovoltaic capacity. CUBETEK(CBTEK) engineers will share with you the knowledge of inverter selection.
In fact, different countries, different user habits and different policies have very different choices of inverters for household photovoltaic energy storage systems! For example, the Pakistani market hopes to install lead-acid batteries + high-frequency inverters; while Nigerian warehouse customers prefer to install power frequency inverters + lead-acid batteries. European users prefer to install high-voltage hybrid energy storage inverters from 5-10 single phase/ 8-20kw three phase storage inverter.
In the selection of household energy storage systems, we generally consider the following factors:
Battery rated voltage, that is, the voltage level of the connected energy storage battery group. The battery voltage of the energy storage inverter is divided into low voltage and high voltage. The low voltage is usually 48V/51.2V, while the high voltage is mostly 300V or higher. The selection of rated voltage is crucial to the matching and overall performance of the inverter and battery.
Maximum charge and discharge current, this parameter is related to the selection of battery cells, charging speed and output power in off-grid state. When selecting an energy storage inverter, special attention should be paid to whether its maximum charge and discharge current meets the actual application requirements.
Maximum component input power refers to the maximum component power that the inverter can connect to. Since the power consumption, usage time and method of energy storage inverter users vary significantly, the parameter range is relatively wide, which is convenient for selecting suitable component capacity according to actual needs.
Maximum photovoltaic input power indicates the maximum power that the photovoltaic part of the inverter can accept, but not the maximum power it can actually handle. For example, a 5kW inverter may have a maximum photovoltaic input power of 7.5kW, but the actual AC output is only 5kW at most. Therefore, when selecting an inverter, in addition to considering the maximum photovoltaic input power, it is also necessary to consider the power that the inverter can actually handle at the same time.
Battery capacity: The capacity of the battery needs to be considered by the load, grid stability, budget, etc., maximum load, average load, and average usage time. Average load * average usage time * (1.28-1.05) for settlement, the minimum coefficient is not less than 1.05
Inverter power selection: based on the total load, inductive load, battery charge and discharge voltage, current, and maximum input of the PV end, the most efficient and economical solution is required!