3.9.1 Îäíîïîëóïåðèîäíûé âûïðÿìèòåëü

1

Ðèñ. 3.20

                                                                                      (3.48)

                                                                                                              (3.49)

 

         Èç ôîðìóëû ñëåäóåò, ÷òî íàïðÿæåíèå íà âûõîäå ñõåìû â  ðàçà ìåíüøå, ÷åì íà âûõîäå òðàíñôîðìàòîðà.

 

                                                                                            (3.50)

 - äåéñòâóþùåå çíà÷åíèå                                                                       (3.51)

                                                                                               (3.52)

                                                                                     (3.53)

 

Çíàÿ ìàêñèìàëüíûé òîê, íàõîäèì

                                                                                                 (3.54)

Íàäî îïðåäåëèòü äåéñòâóþùåå çíà÷åíèå òîêà:

 

                                                (3.55)

 

                                                                    (3.56)

 

,                                      (3.57)

ãäå ,  - ìîùíîñòü âî 2-é îáìîòêå òðàíñôîðìàòîðà

 

         Òàê êàê ìîùíîñòü 2 îáìîòêè áîëåå ÷åì â 3 ðàçà áîëüøå ìîùíîñòè, îòäàâàåìîé â íàãðóçêó, ñëåäóåò ñ÷èòàòü, ÷òî òðàíñôîðìàòîð èñïîëüçóåòñÿ íå ïîëíîñòüþ.

 

Êîýôôèöèåíò èñïîëüçîâàíèÿ ìîùíîñòè âî 2-é îáìîòêå:

                                                                              (3.58)

         Äëÿ îòûñêàíèÿ ýëåêòðîìàãíèòíîé ìîùíîñòè â 1 îáìîòêå òðàíñôîðìàòîðà íåîáõîäèìî íàéòè .

                                                             (3.59)

                                                                     (3.60)

         Òåïåðü íàõîäèì

                                                                (3.61)

                                                                                    (3.62)

         Ãàáàðèòíàÿ ìîùíîñòü òðàíñôîðìàòîðà:

                                                                 (3.63)

Ãàáàðèòíàÿ ìîùíîñòü òðàíñôîðìàòîðà áîëåå ÷åì â 3 ðàçà ïðåâûøàåò ìîùíîñòü, ïåðåäàâàåìóþ â íàãðóçêó - òðàíñôîðìàòîð èñïîëüçóåòñÿ ïëîõî.

 

         Êàê âèäíî èç âðåìåííîé äèàãðàììû ïóëüñàöèÿ íà âûõîäå ÂÓ èìååò âèä ïåðèîäè÷åñêîé, íî íå ãàðìîíè÷åñêîé ôóíêöèè, è èç âðåìåííîé äèàãðàììû ìîæíî óñòàíîâèòü, ÷òî:

                                                                                 (3.64)

         Òîãäà ñàìà àìïëèòóäà

                                                                                   (3.65)

                                                                 (3.66)

                                                                         (3.67)

         f ïóëüñàöèè ïåðâîé ãàðìîíèêè ñîâïàäàåò ñ f ñåòè:

                                                                                         (3.68)

         Ó ñõåìû îäíîïîëóïåðèîäíîãî âûïðÿìèòåëÿ ïîêàçàòåëè íèçêèå.

         Íèçêî÷àñòîòíûå ïóëüñàöèè òðóäíåå ñãëàäèòü, ÷åì âûñîêî÷àñòîòíûå, òàê êàê òðåáóþòñÿ áîëüøèå ¸ìêîñòè è èíäóêòèâíîñòè ôèëüòðîâ (ðàñòóò ñòîèìîñòü, ãàáàðèòû âûïðÿìèòåëåé).

         Òàêèì îáðàçîì, ïî âñåì ýëåêòðè÷åñêèì ïîêàçàòåëåì ðàññìîòðåííàÿ ñõåìà èìååò ñóùåñòâåííûå íåäîñòàòêè.

         Äîñòîèíñòâà:

- å¸ ïðåäåëüíàÿ ïðîñòîòà, 1 âåíòèëü;

- ðàáîòà áåç òðàíñôîðìàòîðà;

- èñïîëüçîâàíèå âñåãî 1 ðàäèàòîðà â ìîùíûõ óñòðîéñòâàõ;

- ìàëîå êîëè÷åñòâî ýëåìåíòîâ;

- íèçêàÿ ñòîèìîñòü;

- íàäåæíîñòü.

Íà ïðàêòèêå äàííàÿ ñõåìà èìååò ñðàâíèòåëüíî îãðàíè÷åííîå ïðèìåíåíèå. Ïðè àêòèâíûõ íàãðóçêàõ (â íèçêîêà÷åñòâåííûõ âûïðÿìèòåëÿõ) è ¸ìêîñòíûõ (â ìàëîìîùíûõ èñòî÷íèêàõ îïîðíûõ íàïðÿæåíèé).

 

 

 

 

 

Òàáëèöà 3.1. Ïàðàìåòðû ðàáîòû îäíîïîëóïåðèîäíîãî âûïðÿìèòåëÿ ïðè àêòèâíîé è åìêîñòíîé íàãðóçêàõ

 (àêòèâíàÿ íàãðóçêà)

 (åìêîñòíàÿ íàãðóçêà)

 

 

Áîëåå ñîâåðøåííî ÿâëÿåòñÿ äâóõïîëóïåðèîäíàÿ ñõåìà âûïðÿìèòåëÿ.