Generator parts AVR 6GA2 490-0A
1): Perfect quality and reasonable price
2):Siemens AVR: 6GA2 490-0A and 6GA2-491
1. OEM service is ok.
2. Factory directly sales.
3. Certification: ISO9001,CE,CSA
4. Delivery time: 3 days
1. Simens AVR 6GA2 490-0A
1. High quality and best price
2. Good reputation and service
3. Fast delivery time
4. MOQ: 5PCS
2.Packaging & Delivery Packaging
Plastic bag and Carton
Delivery Detail: 3days
|Thyristor voltage regulator
|A thyristor voltage regulator was fitted so as to upgrade the ± 5% voltage tolerance previously achieved to ± 0.5%.
|The regulator in question is a pure voltage regulator,
|which uese the excitation current to keep the generator voltage constant irrespective of the load.
|The generator voltage is fed via the measuring circuit transformer to the regulator
|input voltage are derived from this DC voltage.The voltage setpoint is input via an internal reference value potentiometer
|or external reference value setter.
|After an internal setpoint/ actual value comparison, the regulator amplifier outputs a DC voltage,
|which is converted by a loadside pulse generator into a firing pulse with adjustable time offset for the bypass thyristor.
|The bypass thyristor Vabs is situated in the excitation circuit between one phase and the anode-side output of the
|rectifier bridge in series with the bypass resistor Rabs (Fig. 4). The bypass circuit, parallel to excitation winding
|RE, is switched on in the time ranges at which valve V5 is conductive. Part of the excitation current can
|therefore be made to bypass the excitation winding. This takes place within every period for a fraction of that period
|(control angle). The excitation current is reduced in accordance with the control angle and the resistance
|ratio Rabs/ RE.