A filter unit and an internal cleaning system of the air filter aiming to separate dusts from process origin exhaust air in more effective and energy efficient model comprising: (i) a filter cassette (ii) an air nozzle (8.2) capable of travelling inside filter cassettes and blowing cleaning air from an internal surface of the filter cassettes, (iii) telescopic cleaning mechanism that carries and moves the air nozzle (8.2) throughout the length of the filter cassettes while guiding the cleaning air up to the air nozzle (8.2), (iv) a horizontal linear shaft and a vertical linear shaft that support the telescopic cleaning mechanism and are configured to drive it to the required coordinates in X - Y axis, (v) a suction blockage paddle (8.1) controlling the suction power generation at the outlet of filter cassettes entry inside the filtering units, wherein: • the nozzle (8.2) is located at the front of telescopic cleaning mechanism and is able to move for full surface coverage of filter cassette for an effective cleaning performance, • the suction blockage paddle (8.1 is supported by vertical linear shaft and horizontal linear shaft as a part of telescopic cleaning mechanism and it is configured to close the filter cassette entry and to enable the system suction power avoidance when the nozzle (8.2) reaches to the desired distance / position inside the filter cassette at a time as right in advance of air blow from inside of the filter cassettes, • the air nozzle (8.2) is configured to apply low pressure cleaning air from the opposite direction of regular air flow, after the blockage of filter cassette opening by blockage paddle (8.1), for an energy-efficient cleaning of filter cassette from a short distance • the blockage paddle (8.1) is further configured to be moved back after the air nozzle (8.2) stops blowing the air for cleaning and proceeds to the next cleaning stage position, in order to regenerate the suction power and enforce a ripple effect on filter cassette fabrics for breaking the dust blocks and thus better cleaning by the sudden change of the air flow direction • the nozzle (8.2) and suction blockage paddle (8.2) movements are repeatable up to the required number of stages per each filter cassette (i) a filter cassette (ii) an air nozzle (8.2) capable of travelling inside filter cassettes and blowing cleaning air from an internal surface of the filter cassettes, (iii) telescopic cleaning mechanism that carries and moves the air nozzle (8.2) throughout the length of the filter cassettes while guiding the cleaning air up to the air nozzle (8.2), (iv) a horizontal linear shaft and a vertical linear shaft that support the telescopic cleaning mechanism and are configured to drive it to the required coordinates in X - Y axis, (v) a suction blockage paddle (8.1) controlling the suction power generation at the outlet of filter cassettes entry inside the filtering units, wherein: • the nozzle (8.2) is located at the front of telescopic cleaning mechanism and is able to move for full surface coverage of filter cassette for an effective cleaning performance, • the suction blockage paddle (8.1 is supported by vertical linear shaft and horizontal linear shaft as a part of telescopic cleaning mechanism and it is configured to close the filter cassette entry and to enable the system suction power avoidance when the nozzle (8.2) reaches to the desired distance / position inside the filter cassette at a time as right in advance of air blow from inside of the filter cassettes, • the air nozzle (8.2) is configured to apply low pressure cleaning air from the opposite direction of regular air flow, after the blockage of filter cassette opening by blockage paddle (8.1), for an energy-efficient cleaning of filter cassette from a short distance • the blockage paddle (8.1) is further configured to be moved back after the air nozzle (8.2) stops blowing the air for cleaning and proceeds to the next cleaning stage position, in order to regenerate the suction power and enforce a ripple effect on filter cassette fabrics for breaking the dust blocks and thus better cleaning by the sudden change of the air flow direction • the nozzle (8.2) and suction blockage paddle (8.2) movements are repeatable up to the required number of stages per each filter cassette • the nozzle (8.2) is located at the front of telescopic cleaning mechanism and is able to move for full surface coverage of filter cassette for an effective cleaning performance, • the suction blockage paddle (8.1 is supported by vertical linear shaft and horizontal linear shaft as a part of telescopic cleaning mechanism and it is configured to close the filter cassette entry and to enable the system suction power avoidance when the nozzle (8.2) reaches to the desired distance / position inside the filter cassette at a time as right in advance of air blow from inside of the filter cassettes, • the air nozzle (8.2) is configured to apply low pressure cleaning air from the opposite direction of regular air flow, after the blockage of filter cassette opening by blockage paddle (8.1), for an energy-efficient cleaning of filter cassette from a short distance • the blockage paddle (8.1) is further configured to be moved back after the air nozzle (8.2) stops blowing the air for cleaning and proceeds to the next cleaning stage position, in order to regenerate the suction power and enforce a ripple effect on filter cassette fabrics for breaking the dust blocks and thus better cleaning by the sudden change of the air flow direction • the nozzle (8.2) and suction blockage paddle (8.2) movements are repeatable up to the required number of stages per each filter cassette