发明授权
- 专利标题: Electronic ballast with controlled lamp preheating
- 专利标题(中): 电子镇流器带控制灯预热
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申请号: US12605450申请日: 2009-10-26
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公开(公告)号: US08232741B2公开(公告)日: 2012-07-31
- 发明人: Naoki Komatsu , Daisuke Yamahara
- 申请人: Naoki Komatsu , Daisuke Yamahara
- 申请人地址: JP Osaka
- 专利权人: Panasonic Corporation
- 当前专利权人: Panasonic Corporation
- 当前专利权人地址: JP Osaka
- 代理机构: Waddey & Patterson, P.C.
- 代理商 Mark J. Patterson; Gary L. Montle
- 优先权: JP2008-277424 20081028
- 主分类号: H05B37/02
- IPC分类号: H05B37/02
摘要:
An electronic ballast provides controlled preheating for a discharge lamp. A power converting circuit receives a DC power input and converts it into an AC power output. A starting circuit coupled to the power converting circuit generates a high voltage for starting the lamp. A control circuit controls the power converting circuit to generate AC power output to the lamp dependent on a mode of operation. A symmetry detecting circuit determines a positive-negative symmetrical state of the output power provided to the discharge lamp with respect to ground. The control circuit has a starting mode wherein the discharge lamp is triggered to start with a high voltage generated by the starting circuit, an electrode heating mode wherein the AC power output of the power converting circuit is controlled to a first frequency for heating each lamp electrode, and a steady-state mode wherein the AC power output of the power converting circuit is controlled to a second frequency for maintaining lighting of the discharge lamp. The control circuit shifts from the electrode heating mode to the steady-state mode when the symmetry detecting circuit determines that the AC power output is in a positive-negative symmetrical state in the electrode heating operation.
公开/授权文献
- US20100109542A1 ELECTRONIC BALLAST WITH CONTROLLED LAMP PREHEATING 公开/授权日:2010-05-06