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<p style="padding: 0px; margin-top: 0px; margin-bottom: 0px; font-family: "Noto Sans SC", "Microsoft YaHei", ���ź�, -apple-system, BlinkMacSystemFont, "segoe ui", Roboto; color: rgb(51, 51, 51); font-size: 12px; text-wrap: wrap; background-color: rgb(255, 255, 255);"><span style="padding: 0px; margin: 0px; font-size: 14px;">电机模型理论只是描述矢量控制的过程。我们应用工程师只需要知道其<strong style="padding: 0px; margin: 0px;">结论</strong>。通过应用,验证该理论是否正确。</span><br/></p><p style="padding: 0px; margin-top: 0px; margin-bottom: 0px; font-family: "Noto Sans SC", "Microsoft YaHei", ���ź�, -apple-system, BlinkMacSystemFont, "segoe ui", Roboto; color: rgb(51, 51, 51); font-size: 12px; text-wrap: wrap; background-color: rgb(255, 255, 255);"><span style="padding: 0px; margin: 0px; font-size: 14px;">在应用工程师的眼中,这些并不复杂。</span></p><p style="padding: 0px; margin-top: 0px; margin-bottom: 0px; font-family: "Noto Sans SC", "Microsoft YaHei", ���ź�, -apple-system, BlinkMacSystemFont, "segoe ui", Roboto; color: rgb(51, 51, 51); font-size: 12px; text-wrap: wrap; background-color: rgb(255, 255, 255);"><span style="padding: 0px; margin: 0px; font-size: 14px;">我们知道,磁场强度是由<strong style="padding: 0px; margin: 0px;">安</strong>匝决定的,而一台设计好的电机,匝数是确定的。因此,电机可能的输出转矩,是由<strong style="padding: 0px; margin: 0px;">励磁电流</strong>决定的。达不到额定励磁电流,最大转矩就下降(超频弱磁)。</span></p><p style="padding: 0px; margin-top: 0px; margin-bottom: 0px; font-family: "Noto Sans SC", "Microsoft YaHei", ���ź�, -apple-system, BlinkMacSystemFont, "segoe ui", Roboto; color: rgb(51, 51, 51); font-size: 12px; text-wrap: wrap; background-color: rgb(255, 255, 255);"><span style="padding: 0px; margin: 0px; font-size: 14px;">变频器的三相输出配置有电流检测。CU随时知晓当前电流。</span></p><p style="padding: 0px; margin-top: 0px; margin-bottom: 0px; font-family: "Noto Sans SC", "Microsoft YaHei", ���ź�, -apple-system, BlinkMacSystemFont, "segoe ui", Roboto; color: rgb(51, 51, 51); font-size: 12px; text-wrap: wrap; background-color: rgb(255, 255, 255);"><strong style="padding: 0px; margin: 0px;"><span style="padding: 0px; margin: 0px; font-size: 14px;">励磁电流</span></strong><span style="padding: 0px; margin: 0px; font-size: 14px;">的<strong style="padding: 0px; margin: 0px;">实际值</strong>,就是电压输出<strong style="padding: 0px; margin: 0px;">换相点</strong>的电流值!(正交90度)</span></p><p style="padding: 0px; margin-top: 0px; margin-bottom: 0px; font-family: "Noto Sans SC", "Microsoft YaHei", ���ź�, -apple-system, BlinkMacSystemFont, "segoe ui", Roboto; color: rgb(51, 51, 51); font-size: 12px; text-wrap: wrap; background-color: rgb(255, 255, 255);"><span style="padding: 0px; margin: 0px; font-size: 14px;">而当前<strong style="padding: 0px; margin: 0px;">转矩电流</strong>的<strong style="padding: 0px; margin: 0px;">实际值</strong>,就是电压输出<strong style="padding: 0px; margin: 0px;">最大值(峰值)</strong>处的电流值(同相位)。电机<strong style="padding: 0px; margin: 0px;">空载</strong>,<strong style="padding: 0px; margin: 0px;">此</strong>处的<strong style="padding: 0px; margin: 0px;">电流值</strong>,就是<strong style="padding: 0px; margin: 0px;">电机损耗</strong>。</span></p><p style="padding: 0px; margin-top: 0px; margin-bottom: 0px; font-family: "Noto Sans SC", "Microsoft YaHei", ���ź�, -apple-system, BlinkMacSystemFont, "segoe ui", Roboto; color: rgb(51, 51, 51); font-size: 12px; text-wrap: wrap; background-color: rgb(255, 255, 255);"><span style="padding: 0px; margin: 0px; font-size: 14px;">由此可见,<strong style="padding: 0px; margin: 0px;">根本用不到任何理论计算</strong>(什么解耦之类的)。</span></p><p style="padding: 0px; margin-top: 0px; margin-bottom: 0px; font-family: "Noto Sans SC", "Microsoft YaHei", ���ź�, -apple-system, BlinkMacSystemFont, "segoe ui", Roboto; color: rgb(51, 51, 51); font-size: 12px; text-wrap: wrap; background-color: rgb(255, 255, 255);"><span style="padding: 0px; margin: 0px; font-size: 14px;">为啥矢量控制低频时不好用?</span></p><p style="padding: 0px; margin-top: 0px; margin-bottom: 0px; font-family: "Noto Sans SC", "Microsoft YaHei", ���ź�, -apple-system, BlinkMacSystemFont, "segoe ui", Roboto; color: rgb(51, 51, 51); font-size: 12px; text-wrap: wrap; background-color: rgb(255, 255, 255);"><span style="padding: 0px; margin: 0px; font-size: 14px;">例如,输出1Hz,那意味着每秒才能获知一次励磁电流值(换相点)。太过于迟滞了。</span></p><p style="padding: 0px; margin-top: 0px; margin-bottom: 0px; font-family: "Noto Sans SC", "Microsoft YaHei", ���ź�, -apple-system, BlinkMacSystemFont, "segoe ui", Roboto; color: rgb(51, 51, 51); font-size: 12px; text-wrap: wrap; background-color: rgb(255, 255, 255);"><span style="padding: 0px; margin: 0px; font-size: 14px;">因此,低频段,只能用开环的V/f来控制。</span></p><p style="padding: 0px; margin-top: 0px; margin-bottom: 0px; font-family: "Noto Sans SC", "Microsoft YaHei", ���ź�, -apple-system, BlinkMacSystemFont, "segoe ui", Roboto; color: rgb(51, 51, 51); font-size: 12px; text-wrap: wrap; background-color: rgb(255, 255, 255);"><span style="padding: 0px; margin: 0px; font-size: 14px;">反过来说,正常运转时,既然可以知道当前的<strong style="padding: 0px; margin: 0px;">转矩电流</strong>;当然可以根据负载的状态,降低电压、降低励磁电流,使其符仅合当前<strong style="padding: 0px; margin: 0px;">低转矩</strong>的需求。以达到节能的效果。</span></p><p><br/></p> |