Comparison Between Stand Alone Inverter and Modular Inverter

Firstly, Because the principle of the two systems is basically the same, except for the inverter unit, other parts are also the same. Therefore, the controller and other detection functions are similar, which can meet the needs of users to the maximum extent.

Difference:

1. Stand alone inverter failure rate is low.
Because the whole inverter by a single module to achieve a single inverter function, so can minimize the failure rate of the system; The modular inverter system, because of the number of parallel modules, the system failure rate is proportional to the number of modules surge.

2. Stand alone inverter is more suitable for emergency lighting system.
Mainstream EPS manufacturers, regardless of the strength of technical ability, are the same as the stand alone inverter as an important part of EPS, is a best explanation. And in three or four years ago when some enterprises entered the industry, because of their own technical ability is weak, unable to develop a high-power inverter, selfish use of a flexible means. That is, an inverter whose technical capability can be achieved is used as a module, and multiple modules are connected in parallel to form a modular inverter system. But later because of unable to adapt to the development of the industry, and the final choice of the overall inverter scheme.

3. Stand alone inverter has stronger maintainability.
As mentioned above, the failure rate of the stand alone inverter is lower than that of the modular inverter system, and a large number of on-site failures are summarized. In the EPS system with stand alone inverter, the probability of failure of the inverter unit is almost zero, while the probability of failure of the control part is slightly higher. Therefore, as an stand alone inverter, there is no need to keep spare parts of the inverter unit on site. Because of the high failure rate of the modular inverter, it is necessary to have a certain amount of spare modules on site. The two systems are basically the same except the other parts of the inverter unit, and the required spare parts and maintainability are also the same.

Unsatisfactory aspect of stand alone inverter

1. the machine weight is large.
Ωστόσο, the installation is a one-time problem, only a one-time installation position, does not require frequent movement.

2. Poor capacity expansion.
But in general, the load margin has been fully considered before installation, and will not change at will. If it does need to be adjusted, it is just as operable as a modular inverter. Because EPS is a system, the change of inverter unit is bound to require adjustment of charging unit and distribution unit, both of which need to be adjusted. It is irresponsible to say that modular inverters can only be solved by adding a few inverter modules. If the adjustment of other parts is not considered, the overall inverter only needs to replace the inverter unit once. (Φυσικά, the expansion is within a certain range).

3. three-phase load capacity is poor.
For rutting 20KW load, a little electrical knowledge of the people will consider the three-phase balance problem. So at the beginning of the design, electrical engineers will fully consider, as long as not 100% of the phase bias, the overall inverter and modular inverter is no difference.

4. Poor single-phase fault handling ability.
The failure rate of the whole inverter is almost zero, and the probability of single-phase failure is extremely small. So there is no need to consider this function as much as a modular inverter.
A complete system, which requires reasonable system configuration, high reliability of function modules and high economy. The inverter unit, as a part of EPS, must meet the needs of the system, adapt to the application environment of the system, improve the cost performance of the system.