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There are two groups of devices in the current medical oxygen generators. The first group, there are stationary oxygen generators which are massy and have noisy operation due to component used in the generators. Their oxygen production rate can go up to 5 L/min. In the second group, there are mobile devices, which has relatively lower oxygen production rate (up to 2 L/min). The battery used in the system allow to operate them up to 90 minutes. After this period, it is required to power up the system or changing the battery in the system. In both groups of devices, there is no automatic control system. There are many patented devices in the open literature and market. The patents cover the working principle or design of the devices. AIRSEP Corp. (2012) has developed a compact and highly portable combination pressure swing adsorption apparatus and product gas conservation device for medical use, to produce efficiently a gas with a high concentration of oxygen and to deliver the oxygen concentrated gas to a user at selectable times and in selectable doses (up to 5 L/min), in which the operating components are detachably mounted together as a single unit. Jagger et al. (2006) has presented an oxygen concentrator utilizing a vacuum swing adsorption (VSA) gas separation system comprises a cartridge containing a mass of adsorbent material for producing oxygen, and a drive which activates the gas separation system. The concentrator is defined by a ratio of the mass of the adsorbent material compared to a flow rate of oxygen produced by the oxygen concentrator in a range of 0.020 to 0.214 kg/(L/min). Watanabe (2010) has patented an oxygen concentrator which can supply stable feed air to an absorption unit immediately after start-up, even when started-up at low rotation. The aforementioned compressed air generator has a control unit which controls the rotational frequency of the aforementioned rotation body such that the rotational frequency is appropriate with regard to the amount of oxygen being generated. George (1920) has patented the first oxygen concentrator using to be used in industrial applications. Phuc et al. (2013) has developed the oxygen concentrators which achieve reliable pressure control in the oxygen columns with reduced number of components for pressure control in the oxygen columns, and also easy maintenance and reduced power consumption. Cao et al. (2013) has designed a method of controlling an oxygen concentrator. Vorih (1993) has developed an operating system for dual-sieve oxygen concentrators, as used by invalids, provides a method and apparatus for controlling the purging and release of product gas and the cycling period in response to the pressure build-up in each sieve column. Ebers et al. (2013) has presented a novel oxygen concentrator which is easy to produce and simple to use, with low noise emissions and vibration. Galbraith et al. (2010) has developed an ultra rapid cycle portable oxygen concentrator which has lightweight, portable oxygen concentrators that operate using an ultra rapid, sub one second, adsorption cycle based on advanced molecular sieve materials. Atlas et al. (2014) has patented a portable oxygen concentrator which including a pressure swing absorption system defined by a relatively rigid housing adapted to generate a flow of oxygen enriched gas and a battery adapted to provide power to the pressure swing absorption system. 2 of 8 Latest version March 2024 Yamaura and Kiriake (2014) has developed an oxygen concentrator which allows the flow rate setting to be changed safely and securely by the patient using a remote- control device. Additionally, in order to clarify the importance of the oxygen generator and their role in the near future, the World Health Organization (WHO) has shared some statistics regarding the oxygen therapy, oxygen supply, related market. According to the WHO, the demand for oxygen worldwide has significantly increased due to the COVID-19 pandemic. • The WHO has reported that the need for oxygen has increased to 1.1 million cylinders in low to middle-income countries alone. • It is estimated that more than half a million people in these countries currently need 1.1 million cylinders of oxygen per day, with 25 countries currently reporting surges in demand. • Oxygen is an essential medicine used to care for patients at all levels of the healthcare system, including in surgery, trauma, heart failure, asthma, pneumonia, and maternal and childcare. • Pneumonia alone accounts for 800,000 deaths per year. It is estimated that 20– 40% of these deaths could be prevented with the availability of oxygen therapy. • As of February 2021, the WHO and partners have distributed over 30,000 concentrators and 40,000 pulse oximeters and patient monitors, reaching 121 countries, including 37 countries that are classified as “fragile”. • A study of patient use showed that nearly 80% of patients using Portable Oxygen Concentrators (POCs) were prescribed oxygen for Chronic Obstructive Pulmonary Disease (COPD). Another 6.7% were prescribed oxygen for interstitial lung disease. • The global oxygen concentrator market reached $3.5 billion in 2023 and is expected to see annual growth of 5.3% through 2030. • The worldwide market for Portable Oxygen Concentrators, at $1 billion in 2019, will grow to $3 billion by 2026. It is clear from these statements that the oxygen supply is critical to the patient and their life quality. It is not possible to meet all oxygen demands by cylinders as they need all the time. Therefore, continuously working oxygen generator are required for the people, as it is not possible to keep the patient at the hospitals only for oxygen therapy.