為了有效地提升鉛酸蓄電池的使用壽命,同時實現對充電過程的監控,設計出一種用單片機控制的36 V鉛酸蓄電池充電電源。本電路采用反激式拓撲,連續電流工作模式,電源管理IC設計在電源的副邊,由ELAN公司的EM78P258N單片機模擬,是用可編程器件模擬電源管理IC,實現智能電源低成本化的一次成功嘗試,通過對單片機的軟件設計實現了充電電源的狀態顯示、充電時間控制、報警、過溫保護、過壓保護、過流保護等功能。本充電器真正的實現了鉛酸蓄電池的三段式充電過程,其最高輸出功率可達90 W,效率約85%,成本不到20元,具有很高的市場競爭力。
Abstract: In order to extend the life of lead-acid battery efficiently and supervise the charging process meanwhile, a 36V lead-acid battery charge powe supply controlled by microcontroller is designed. The charger is flyback switching power supply and works in CCM mode. A EM78P258N microcontroller made by ELAN microelectronics corporation is used as power management IC which is designed at the secondary circuit. The project is a successful attempt to low-cost intelligent power used microcontroller simulating power management IC. The charger also has the functions of the status reveal, charge time control, alarming, thermal protect, current limit and overvoltage protect by the software design. The circuit actually implements the three-step charge process, whose power is up to 90W and whose efficiency can get 85%. The net cost of this charger is less than 20 RMB, so that the charger is of powerful market competitiveness.
介紹了用單片機C 語言實現無功補償中電容組循環投切的基本原理和算法,并舉例說明。關鍵詞:循環投切;C51;無功補償中圖分類號: TM76 文獻標識碼: BAbstract: This paper introduces the aplication of C51 in the controlling of capacitorsuits cycle powered to be on and off in reactive compensation.it illustrate thefondamental principle and algorithm with example.Key words: cycle powered to be on and off; C51; reactive compensation
為提高功率因數,往往采用補償電容的方法來實現。而電容器的容量是由實時功率因數與標準值進行比較來決定的,實時功率因數小于標準值時,需投入電容組,實時功率因數大于標準值時,則需切除電容組。投切方式的不合理,會對電容器造成損壞,現有的控制器多采用“順序投切”方式,在這種投切方式下排序在前的電容器組,先投后切;而后面的卻后投先切。這不僅使處于前面的電容組經常處于運行狀態,積累熱量不易散失,影響其使用壽命,而且使后面的投切開關經常動作,同樣減少壽命。合理的投切方式應為“循環投切”。這種投切方式使先投入的運行的電容組先退出,后投的后切除,從而使各組電容及投切開關使用機率均等,降低了電容組的平均運行溫度,減少了投切開關的動作次數,延長了其使用壽命。