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電(dian)(dian)力系(xi)統的主體結構(gou)有電(dian)(dian)源(yuan)（水(shui)電(dian)(dian)站、火電(dian)(dian)廠(chang)、核電(dian)(dian)站等發電(dian)(dian)廠(chang)），變電(dian)(dian)所(suo)(suo)（升壓變電(dian)(dian)所(suo)(suo)、負荷中(zhong)心變電(dian)(dian)所(suo)(suo)等），輸電(dian)(dian)、配電(dian)(dian)線路和(he)負荷中(zhong)心。各電(dian)(dian)

源點還互相聯接以實現不同地(di)區(qu)之間的電能交(jiao)換和(he)調節，從而(er)提高供(gong)電的安全性和(he)經濟性。