圖 5.10 到圖 5.14 為不同振動頻率之實作波形，包含了全橋式反流器與空白 時間補償之串接全橋式反流器，實作中低頻的電流追隨能力較高頻為佳，振動頻 率越高頻電流追隨得越差。
全橋式反流器的電流頻率為 100kHz，而串接全橋式反流器的電流頻率為 200kHz，如實作波形所示，不管是在何種振動頻率下全橋式反流器的電流漣波 明顯較串接全橋式反流器高。
從實作圖中可以看出加入空白補償之後縮短了電流為零的時間，使電流更接 近弦波，改善在電流命令小時空白時間對於輸出電壓的影響，證實了空白時間補 償器可以改善空白時間的影響。而在低頻的部分由於電流本身就已經是弦波了，
所以空白時間補償器在低頻時的效果較不明顯。振動頻率在高頻時因為接近另一 機械共振頻率 fo,am，因此在加速度中有約 10kHz 的振動頻率。
io io*
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io io*
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(b)
圖 5.10 振動頻率 5Hz (a)全橋式反流器; (b)空白時間補償之串接全橋式反流器
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io i*o
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圖 5.11 振動頻率 250Hz (a)全橋式反流器; (b)空白時間補償之串接全橋式反流器
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圖 5.12 振動頻率 500Hz (a)全橋式反流器; (b)空白時間補償之串接全橋式反流器
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io io*
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圖 5.13 振動頻率 1000Hz (a)全橋式反流器; (b)空白時間補償之串接全橋式反流 器
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io io*
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圖 5.14 振動頻率 2000Hz (a)全橋式反流器; (b)空白時間補償之串接全橋式反流 器
第6章
結論
傳統線性功率放大器具有效率低、重量重和體積大等缺點，這些缺點可藉由 使用切換式反流器來改善，一般切換式反流器採用全橋式反流器來實現，而本論 文以串接全橋式反流器實現電動式振動機之電流追隨，串接全橋式反流器可以降 低電流漣波也可以減少電壓諧波，本論文還加入了空白時間補償器來補償為了避 免上下臂開關短路的空白時間，空白時間補償器可完整補償因為空白時間造成的 電壓損失或增加，由模擬及實作圖可以發現空白時間補償器對於改善電流波形非 常有效，可以使電流更接近弦波。
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