公开(公告)号：EP0706306A3

公开(公告)日：1997-12-10

申请号：EP95115730.4

申请日：1995-10-05

申请人： NEC CORPORATION

发明人： Kawashima, Shingo, c/o NEC Corporation

IPC分类号： H05B41/24 ,  H05B41/29

CPC分类号： H01L41/044 ,  H05B41/2822

摘要： An apparatus for controlling a piezoelectric transformer is disclosed. A transformer driver (12) supplies the transformer with a driving voltage the frequency of which is controlled by a frequency oscillator (18). A load current monitor (20, 22, 24, 26) observes a load current flowing through a load such as a fluorescent which is powered by said transformer. A frequency sweep controller (16) controls the frequency oscillator, when the transformer is initially energized, so as to execute a downward frequency sweep wherein the frequency of the driving voltage is swept from a predetermined upper frequency to a predetermined lower frequency. The frequency sweep controller further controls the frequency oscillator, after the transformer has been brought into stable operation, so as to execute the downward frequency sweep when the load current reduces to a second preset level lower than the first preset level.

摘要翻译： 公开了一种用于控制压电变压器的装置。 变压器驱动器（12）向变压器提供频率由频率振荡器（18）控制的驱动电压。 负载电流监视器（20,22,24,26）观察流过诸如由所述变压器供电的荧光灯的负载的负载电流。 当变压器初始通电时，频率扫描控制器（16）控制频率振荡器，以便执行向下的频率扫描，其中驱动电压的频率从预定的上限频率扫描到预定的较低频率。 在变压器进入稳定运行之后，频率扫描控制器进一步控制频率振荡器，以便当负载电流降低到低于第一预设电平的第二预设电平时执行向下频率扫描。

公开(公告)号：EP0762808A3

公开(公告)日：1997-05-21

申请号：EP96113863.3

申请日：1996-08-29

申请人： MATSUSHITA ELECTRIC INDUSTRIAL CO., LTD.

发明人： Kawasaki, Osamu

IPC分类号： H05B41/29

CPC分类号： H01L41/044 ,  H05B41/2822 ,  H05B41/392

摘要： An inverter power source apparatus using a piezoelectric transformer, has : variable oscillating device for oscillating a pulse signal; pulse-width changing device for changing a width of said pulse signal of said variable oscillating device; driving device for generating a driving signal on the basis of an output of said pulse-width changing device; a piezoelectric transformer which is driven by said driving signal, drives a predetermined load, and has input and output electrodes; detecting device for detecting a relationship between said driving signal and a resonance frequency of said piezoelectric transformer, and for, on the basis of a result of the detection, controlling a frequency of said oscillation signal of said variable oscillating device so that a difference between said resonance frequency and a frequency of said driving signal is substantially within a preset range; and pulse-width controlling device for, when a detection results of said detecting device shows that said difference between said resonance frequency and said frequency of said driving signal is substantially within said preset range, controlling said pulse-width changing device so that a current flowing through said load is substantially constant.