AC Synchronous Reluctance motors

Transcription

1 AC Synchronous Reluctance motors

2 AC Synchronous Reluctance Motors Invented many years ago but developed for production in series only recently the Synchronous reluctance motors combine the advantage of the robust and simple design typical of the asynchronous motors with the performances and high efficiency of the Permanent magnets motors. Most of the components used for the stator, shields, ventilation and all the minor components are the same as the ones used for the production of the Asynchronous motors. The performances of the QSR motors (Square SRM) are higher than the IEC motors if compared with the same frame size, giving evident advantages in terms of dynamic and installation volume. Magnetic design is optimized only for inverter duty operation, DOL is not permitted. 2

3 Description WHAT is a SYNCHRONOUS RELUCTANCE motor? The SYNCHRONOUS RELUCTANCE MOTOR is an electrical rotating machine that converts the electrical power into mechanical power. As construction and production process the SRM is similar to all the Asynchronous motors. Only the rotor design has significant difference, SRM rotor is anisotropic (not symmetrical) The rotor has Severall identical slots, with same dimensions and shape and symmetrically distributed. The rotor has Identical sectors with severall diferent slots, with different dimensions and shape and not symmetrically distributed. 3

4 Description Why SYNCHRONOUS RELUCTANCE motor? AIR, high Rel. IRON, low Rel. Synchronous: because when rotating the rotor mechanical speed is exactly in synchronism with the rotating magnetic field. Reluctance: because the magnetic design of the rotor has areas of high RELUCTANCE (white areas, air) and areas of low RELUCTANCE (blue areas, iron). 4

5 Description What is the reluctance: The RELUCTANCE is a magnetic resistance and is the opposite of the permeance. The rotor reluctance depends from the empty areas present on the rotor laminations that creates a kind of magnetic barrier where the flux find high resistance to flow. 5

6 Description How does it function! When the stator windings are excited a magnetic field is generated and the rotor aligns its most magnetically conductive axis (d-axis) with the applied field in order to minimize the reluctance in the magnetic circuit. The Synchronous Reluctance motors are engineered intentionally with rotors made with identified sectors (depending of the nr. of poles) and are made with magnetically conductive material (iron) and magnetically insulating material (air). 6

7 Description Synchronous Reluctance ROTOR Mechanical construction of the rotor seems to be quite simple since does not require aluminium/copper casting or magnets assembly but its design is complex due to the particular shape of the rotor slots that must keep the necessary robustness with a minimized connection sectors between the rotor poles. Advantages if compared to Asynchronous or Permanent Magnets rotors: Rotor without permanent magnets. No fundamental rotor losses (I 2 R), highest possible efficiency. No rotor slip (additional losses). Easy maintenance if compared to PM motors. Cold rotor (low bearing working temperature). 7

8 Efficiency Efficiency Tipical percentage of the losses for a 55kW motor 4P 1500rpm. ASM SRM Core (steel); 20 Asynchronous - losses % Friction; 5 Stray; 10 Stator I2R; 40 Core (steel); 30 SRM - losses % Friction; 5 Stray; 10 Stator I2R; 55 Rotor I2R; 25 8

9 Efficiency The Synchronous reluctance rotor has not the short circuit cage inside and so the rotor losses are not influenced by the Joule effect (I 2 R rotor). For this reason the Synchronous reluctance motors are normally called cold rotor motors. ASM SRM 9

10 SRM Oemer Production Program 10

11 SRM Oemer Production Program Available speed and catalogue data DATI ELETTRICI E PRESTAZIONI ELECTRICAL DATA AND PERFORMANCES ELEKTRISCHE DATEN UND LEISTUNGEN QSR nn 580 rpm nn 1000 rpm nn 1500 rpm nn 1800 rpm nn 2200 rpm nn 2600 rpm Un 360Vac Un 360Vac Un 360Vac Un 360Vac Un 360Vac Un 360Vac QSR - IP 54 - IC 416 Motor Pn Kw In A Pn Kw In A Pn Kw In A Pn Kw In A Pn Kw In A Pn Kw In A nmax 2) Mmax J W Type Mn Nm η % Mn Nm η % Mn Nm η % Mn Nm η % Mn Nm η % Mn Nm η % rpm Nm Kgm 2 Kg 100S 100X 132S 132X 160S 160P 180S 180P 225S 225X 280S 280P 1,7 4,3 2,8 7,2 4,0 10,0 4,8 12,0 5,6 13,9 6,2 15,5 28,0 85,2 26,7 88,7 25,5 91,5 25,5 92,1 24,2 92,1 22,9 92,1 4,7 11,4 7,7 19,3 11,0 27,0 13,2 32,2 15,3 37,3 17,2 42,0 77,0 87,8 73,5 91,5 70,0 93,6 70,0 94,1 66,5 94,2 63,0 93,8 4,7 11,4 7,7 19,3 11,0 27,0 13,2 32,2 15,3 37,3 17,2 42,0 77,0 87, ,5 70,0 93,6 70,0 94,1 66,5 94,2 63,0 93,8 10,6 25,4 17,5 42,9 25,0 60,6 30,0 72,4 34,8 84,0 39,0 94, , , , , , ,1 12,8 30,4 21,0 51,5 30,0 72,4 36,0 86,6 41, , , , , , , ,4 23,4 55,1 38,5 93,4 55, , , , , , , , ,0 23,4 55,1 38,5 93,4 55, , , , , , , ,0 46,8 109,4 77, , , , , , ,3 46,8 109,4 77, , , , , , ,3 76, , , , , , , , , , , , , , , , , , , , , , , , , , , , , ,

12 SRM Oemer Production Program More details are available on our webpage, download section. Thank you 12