Ceiling Fan Motor Analysis December, 2010 Energy Star Program -- Residential Ceiling Fans (Version 2.3) Residential ceiling fan is defined as a non-portable device designed for home use that is suspended from the ceiling for circulating air via the rotation of fan blades. • Some ceiling fans also have an integral or attachable light kit. Key Requirements • Minimum CFM and CFM/watt requirements • Pin based option in light kits • Minimum 30-year motor, 1-year component, and 2-year light kit warranty requirements Fan Speed Minimum Airflow Efficiency Requirement Low 1,250 CFM 155 CFM/watt Medium 3,000 CFM 100 CFM/watt High 5,000 CFM 75 CFM/watt Magnequench -All Rights Reserved Other Ceiling Fan-Related Trends Energy efficient Quiet Designer Incorporating light fixture Magnequench -All Rights Reserved Type of Motor used in Ceiling Fans and Salient Feature of the Conventional Motor Ceiling Fans are direct driven mostly using single-phase Induction motor. • Split-phase permanent capacitor • Capacitor start, capacitor run • Shaded pole motor Motors have windings wound for 18, 20 or 22 poles, resulting in to lower operating speeds (Most common: 18 pole). The rotor resistance is very high for wide speed control range using the stator voltage control. The operating speed range for the ceiling fans are • 180 rpm to 380 rpm for countries like India • 110 rpm to 220 rpm for Developed World • Low Speed is approx. half of high speed Magnequench -All Rights Reserved Type of Motor used in Ceiling Fans and Salient Feature of the Conventional Motor High speed motor efficiency of about 20%. In India the minimum air delivery to achieve 5-star energy rating is 210 m3/min, i.e. If the Fan draws 52.5 W or less then it is qualified for 5-star energy rating. The hub diameter is about 15% of the tip diameter. The blade angle is about 10° to 15° and constant from hub to tip. Between low and high speeds three to five operating speed at equal interval is achieved using the variable speed control. Magnequench -All Rights Reserved Improvement in Ceiling Fan Performance by Motor Design Replacing the conventional 1-phase induction motor with energy efficient 1-phase induction motor • • • • • • Higher efficiency compared to the conventional motor Rotor bars are made up of copper instead of aluminium Increase in copper Increase in Iron Higher Cost compared to conventional 1-ph. Induction Motor Example: 70 W input power can be reduce to 50-55 W. Replacing the conventional 1-phase induction motor with 1-phase / 3-phase PMBL DC motor • Higher efficiency compared to the energy efficient 1-phase induction motor at all the speeds • Higher Motor Cost due to the presence of Magnet, Electronics and Sensors Magnequench -All Rights Reserved Improvement in Ceiling Fan Performance by Motor Design Small pay back period for the additional cost Difficulty in achieving the sensorless operation due to low operating speed Single phase PMBL DC motor should have a non-uniform airgap to achieve starting torque at all rotor positions. In case of fan with 1-ph. PMBL DC motor, when the fan is switched off, Jerky motion of rotor due to preferred parking position of the rotor. Magnequench -All Rights Reserved Benchmarked Ceiling Fans No. Fan Manufacturer Supply Motor Magnet Controller 1 Emerson 120 VAC, 60 Hz PSC type single phase Induction None Using Different value of Capacitances Emerson 120 VAC, 60 Hz 3-Phase PMBL DC Rubber Ferrite Rhine Electronics Co. Ltd. Model No. RH-165M 120 V AC, 60 Hz, 0.65 A, 40 W, 210 rpm 2 3 Regency 120 VAC, 60 Hz 3-Phase PMBL DC Rubber Ferrite Model No. RH 787 RX FR-7871-SS-02 120 V, 60 Hz, Motor:35 W max 4 Monte Carlo 120 VAC, 60 Hz 3-Phase PMBL DC Sintered Ferrite Arc Youngo Ltd., Model BJX1514AST, 120 V AC, 60 Hz, 3 A Amasco 240 VAC, 50 Hz 3-Phase PMBL DC Rubber Ferrite 5 Magnequench -All Rights Reserved FR-7872LL-01 Fan Model CF955 Midway Eco 54” Dia. (CF9550RB) Regency Gladiator III MonteCarlo Avanti 52” Amasco Coaster 54” (Model AMC333) Testing Methodology Magnequench -All Rights Reserved Testing of PSC Single Phase Induction Motor from Emerson Ceiling Fan Speed and direction controller Magnequench -All Rights Reserved Aluminum die cast in rotor Testing of PSC Single Phase Induction Motor from Emerson Ceiling Fan V (Volts) I (A) Pin (W) PF Pout (W) η (%) N (rpm) T (mN-m) 119.46 0.84 100.05 1.00 16.14 16 175.70 877.21 110.12 0.78 85.07 1.00 12.75 15 165.00 737.96 100.15 0.71 70.65 1.00 9.46 13 149.20 605.30 90.10 0.64 57.29 0.99 6.74 12 132.10 486.85 80.13 0.57 45.42 0.99 4.67 10 116.10 383.77 V (Volts) I (A) Pin (W) N (rpm) f (Hz) 140.59 0.95 133.28 212 59.96 130 0.8956 117.01 197 59.96 120.13 110.22 0.8257 0.7616 98.93 83.71 176 165 59.96 59.96 100.16 0.7013 70.74 149 59.96 90.62 0.6306 56.97 132 59.96 80.74 0.5631 45.32 116 59.96 Magnequench -All Rights Reserved Testing of PMBL DC Motor from Emerson Ceiling Fan Summer Use (CCW from bottom) Speed setting Supply Volt (V) I (A) Pin (W) N (rpm) 1 120 0.044~0.048 2.2~2.9 52 2 120 0.055~0.06 3.2~3.8 83 3 120 0.075~0.09 5~5.8 116 4 120 0.12~0.15 8.5~9.5 148 5 120 0.19~0.22 11~13.5 170 6 120 0.33~0.38 22~24 213 Winter Use (CW from bottom) Magnequench -All Rights Reserved Speed setting Supply Volt (V) I (A) Pin (W) N (rpm) 1 120 0.043~0.05 2.2~2.7 50 2 120 0.053~0.057 3.1~3.6 72.5 3 120 0.065~0.075 4.3~5.0 95 4 120 0.095~0.105 6.2~7.1 118 5 120 0.145~0.165 9.4~10.3 141 6 120 0.22~0.245 13.5~14.8 165 Benchmarking of PMBL DC Motor from Emersion Ceiling Fan Magnequench -All Rights Reserved Testing of PMBL DC Motor from Monte Carlo Ceiling Fan Summer Use (CCW from bottom) Speed setting Supply Volt (V) I (A) Pin (W) N (rpm) 1 120 0.03~0.037 1.7~2.1 40 2 120 0.12~0.14 6.9~7.8 86 3 120 0.17~0.195 10.5~11.8 101 4 120 0.35~0.39 21.5~23.5 132 Winter Use (CW from bottom) Magnequench -All Rights Reserved Speed setting Voltage Current (A) Pin (W) N (rpm) 1 120 0.031~0.037 1.7~2.2 40 2 120 0.11~0.13 6.9~7.9 87 3 120 0.17~0.19 10.1~11.3 102 4 120 0.35~0.38 21.5~23.3 134 Benchmarking of PMBL DC Motor from Monte Carlo Ceiling Fan 42 Magnequench -All Rights Reserved Benchmarking of PMBL DC Motor from Ceiling Fans – Motor Details Parameter No. of stator slots / Magnet poles No. of laminations on stator Thickness of stator lamination (mm) No. of turns/ coil Overall diameter of motor (mm) Winding conductor diameter (mm/ AWG) Outer diameter of the magnet (mm) Inner diameter of the magnet (mm) Thickness of the magnet (mm) Axial length of the magnet (mm) Outer diameter of the stator (mm) Axial length of the stator (mm) Length of airgap (mm) Thickness of the rotor back iron (mm) Axial length of the back iron (mm) Shaft diameter (mm) Weight of copper (gm) Weight of magnet (gm) Weight of iron in stator laminations (gm) Weight of rotor back iron (gm) * Based on back iron OD and axial length of magnet Magnequench -All Rights Reserved Fan Manufacturer Emersion 9 / 12 49 0.51 450 140.9 0.47/ 26 137.3 121.76 7.77 34.5 120.00 25.00 0.88 1.80 56.74 17~18 442.8 392 997.30 338.20 Monte Carlo 12 / 8 36 0.50 550 162.0 0.34/ 29 156.00 143.90 6.05 19.90 142.20 18.00 0.85 3.00 29.20 17.00 358.40 202.40 1441.20 334.43 Regency 9 / 12 60 0.51 499 100.6 0.34/29 96.83 86.43 5.20 44.60 84.80 30.34 0.82 1.88 57.00 17.23 258.20 243.90 581.30 250.40 Amasco 9 / 12 49 0.50 800 140.9 0.42/ 27 137.30 122.00 7.65 34.62 120.00 25.00 0.95 1.80 56.71 17.20 655 389 995.10 341.71