摘要 |
Method and device for operating electronic ballasts for High Intensity Discharge lamps (4), the ballasts having a driver (MGD), two power switches (PS1, PS2), an LC series circuit (L, C1, C2), a driver controller (6), a current sensor (8), and a power sensor (10), the method including (a) generating pulses of frequency f1 for a time t1, equal to n/f1, where f1 equals the LC resonance frequency; (b) monitoring the existence of current and (c) monitoring the current in the lamp circuit, and proceeding to (h) upon determining that there is no current in the lamp circuit, (d) continuing pulse generation for a time t2; (e) switching the frequency f2, at which a set power is reached; (f) monitoring and stabilizing the lamp power by modifying f2, and proceeding to (h) when the set power is exceeded; (g) monitoring current and power according to (c) and (f); (h) inhibiting pulse generation for a time approximately equal t2/k; (i) proceeding to (a) until t2 has elapsed; and (j) inhibiting pulse generation until power is switched off and on.
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