Is The Traditional ECO Mode UPS Uninterruptible Power Supply Really Energy-saving?

- Oct 10, 2019-

Is the traditional ECO mode UPS uninterruptible power supply really energy-saving and environmentally friendly? As the size and number of data centers continue to expand, the energy consumption problem becomes more serious. How to reduce the operating cost and power consumption of the data center is a key indicator to improve operational efficiency. In the data center energy distribution, UPS's power loss accounts for a large proportion, so reliable and efficient power supply and distribution systems become the driving force for the green transformation of the data center. In this regard, the industry is actively trying to save energy-saving measures of various UPS systems, ECO mode is a better energy-saving measure of UPS system.

How ECO works

When the quality of the mains is excellent, the UPS main system supplies power to the load through the bypass EMC filter output, and the inverter stands by; when the mains voltage or frequency exceeds a certain range, the UPS switches to the double conversion mode. In the case of normal power supply of the main power supply, the uninterruptible power system supplies the main power through the static bypass to maintain the operation of the inverter.

If the power supply specification exceeds the allowable range (voltage or frequency) of the ECO mode, the uninterruptible power system automatically switches to the standard mode and supplies the inverter with the inverter. If the main power supply specification remains within the input tolerance range, the station's uninterruptible power system will remain in online mode; otherwise, it will operate in battery mode. Compared to the online mode, the ECO mode brings 4% to 4.5% higher operational efficiency.

Compared to the online mode, the ECO mode does not ensure that the frequency and voltage waveforms are sinusoidally stable, as the associated waveform parameters are often affected by the static bypass line. The time required to detect these parameter changes is approximately 3 milliseconds. Therefore, it is recommended that you consider whether to use this ECO mode depending on the degree of protection your load requires. This mode is disabled by default. In addition, this function setting can only be performed when the uninterruptible power system is in bypass mode. If your uninterruptible power system is in online mode, please turn off the system first, and then restart the uninterruptible power system after enabling the ECO function.

Is the traditional ECO mode UPS really energy efficient?

As we all know, the UPS uninterruptible power supply mode is double conversion. The mains is rectified and filtered, and the output quality is excellent. The sine wave voltage is especially suitable for occasions requiring high quality power supply. China has been vigorously promoting environmental protection and energy conservation. The ECO energy-saving mode is to make the UPS power supply host work efficiency of 98%, saving 8% of the loss compared with the general working mode.

Parallel UPS system ECO mode for dual busbars and above. Under this premise, even if the ECO mode power supply fails, the system can still guarantee normal power supply. Through extensive comparison and testing, it is proved that after the ECO mode is modified, the change of power supply reliability is completely within the acceptable range; at the same time, the switching logic adopted by the UPS system of the parallel UPS system is uninterrupted switching, even in the worst case. The switching time is also less than 5ms, and based on tests for voltage phase differences and frequency changes, IT equipment is fully capable of withstanding these switching conditions. Objectively speaking, the ECO mode is of great use in parallel UPS systems.

It is worth mentioning that it also points out the problems that should be paid attention to when applying the ECO mode. For example, ECO mode is not recommended in grid environments such as voltage surges, switching transients, transient spikes, and in the state of the oil machine. It is recommended to add a source filter to the harmonics of the load equipment. It should be emphasized that before adopting the ECO mode, it is necessary to determine the parallel bypass current sharing. If the parallel machine is greater than or equal to 2 devices, the current sharing inductor should be installed. In addition, the ability of the IT load to adapt to the power supply must be wider than the switching conditions, otherwise there will be downtime problems. It greatly reflects the feasibility and application effect of the ECO system of the parallel UPS system in actual operation.

The ECO mode of the UPS power supply and the function of the EPS power supply are basically the same, which is an impact on the EPS, and the performance is better than the EPS. Especially in the reaction time, the original EPS reaction time is not good. After the ECO mode, the UPS with ECO function on the elevator is also a trend.