系统负荷自动调节...

请问热源和热交换系统中的<span style="FONT-SIZE: 10.5pt; FONT-FAMILY: 宋体; mso-bidi-font-size: 12.0pt; mso-bidi-font-family: &quot;Times New Roman&quot;; mso-font-kerning: 1.0pt; mso-ansi-language: EN-US; mso-fareast-language: ZH-CN; mso-bidi-language: AR-SA;">系统负荷自动调节是怎么回事，请高手赐教</span>