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电控入门之四(电机FOC,如何动能回收)

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发表于 2025-6-15 11:06:43 | 显示全部楼层 |阅读模式
电控入门之四(电机FOC,如何动能回收)(87 封私信 / 76 条消息) 电控入门之四(电机FOC,如何动能回收) - 知乎https://zhuanlan.zhihu.com/p/271678646
[color=var(--GBK03A)]袁玉斌

[color=var(--GBK04A)][color=var(--GBK04A)]这个世界从来就不公平,你有多努力,你就有多特殊





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先看系列1,2,3
袁玉斌:电控入门之一(电机FOC,电机为什么能转)739 赞同 · 71 评论文章
袁玉斌:电控入门之二(电机FOC,SVPWM生成)852 赞同 · 116 评论文章
袁玉斌:电控入门之三(电机FOC,用svpwm让电机转起来)594 赞同 · 86 评论文章
FOC从来都是和能量回收联系在一起的,但是这个能量回收是怎么发生的?
我们先看一个场景:
假设电池的母线电压是50v,电机空载转速是3000rpm,显然电机转到3000rpm后转不上去了是受到母线电压的限制,一般这时候是电机的反电动势很靠近母线电压了,没有足够的电压差产生电流,来让电机继续加速,所以速度就上不去了,这应该是搞foc的人,到了某个阶段会产生的理解,一点没毛病,十分正确;但是看接下来的问题?
电机在1000rpm的时候,电机的反电动势是肯定比电池母线电压要低的多的啊,那这个时候为什么能够把电流反向推到正母线上,充入电池?反电动势明明低于电池电压的,电流是逆着压差走的?为啥还能走进去?
这个文章对于回充电的解释,将围绕着这个话题来展开!
当遇到难理解的问题的时候,我们一定要回到物理世界本事来看,基本物理定律大概率一般是不会有问题的,比如说电流定律,电压定律,电流能流入电池正P+这里,只能说明这时候的电压一定是比P+高的,那是怎么高起来的?我们下面来一点点看
看读者反馈公式太多,看不下去了,其实就一个电压方程,在前面的几章里面我讲过,但是显然公式是比较讨人厌的,所以我决定这块重新写,公式的部分我不删除了,想看的同学可以继续看
刚刚说到物理的定律一定不会错,那么电流能流入电池P+就说明电机的三相线的抽头上产生了大于电池电压P+的电压了,这个电压怎么产生的?

首先微观看世界:
我们来看下svpwm的工作过程:


图1
我们看7断式的svpwm,看上图1中的U0和U7,我们会注意到,U0是上桥mos全开,U7是下桥mos全开的过程,这个过程等于短路了电机的三个相线,这时候,如果电机在旋转,反电动势不为0,那么这时候反电动势是加在电机内阻上的,电机相线里面就会自己产生电流的(可以参考下图2中的三相桥臂,1表示上桥的开关合上了,0表示下桥的开关合上了);
因为电机相线里面是RL模型,电机旋转,那么转子磁场就能在绕组线圈上产生感应电动势,这就是电机的旋转反电势,这个电压加在相线绕组上面后,相线里面的电流是逐渐爬升的,所以这两个零矢量作用的时间越长,电机里面的电流就会越大;
图1中的开关状态从U0到U2到U1到U7到U1到U2,可以看出来过了0矢量U7之后,是对应的U1和U2状态,这个状态其实打开了部分上桥mos也关断了部分,同时也是打开了下桥的部分mos,也关断了下桥的部分mos,如果我们操作的mos开关的合适,可以刚好在0矢量作用完成之后,形成一个相电流方向指向母线正的通路方向,就如图2中的1(0,0,0)变到2(1,0,0)的状态,由于相线上是有电感的(相本身就是个绕线圈),所以这个相里面的电流不会突然消失;
母线正的电压是高于电机的旋转反电动势的,但是相电流要流动,改变这个电流的流动方向或者大小,那就是让电感中的电流产生变化,这就会有个感应电势出来,这个感应电势的电压会高过母线正的电压,为什么?因为只有高过母线正的电压,才能维持这个电流继续保持原来的方向流动,这样其实就把电流推入到电池里面去了!
这就像将一个通电绕线圈突然断开,断开的瞬间结合处会产生很高的打弧电压一样;我们可以理解:在电感中流动的电流有很大的惯性,越是大的电感,越是大的电流,惯性越大!同时这个电流也不容易停住;
ok,这就完成了回充的微观过程了!如下图2,一开始是U0(0,0,0)矢量绕组内积蓄电流,然后切换成为了U4(1,0,0)矢量,电流要流向母线正,如果母线正电压高不让进去,那么这个电流就要消失,消失这个动作会产生更高的感应电压,把电流顶进去母线正,这就产生了回充母线,我们还可以控制这两个过程的时间比例,来控制回充的比例和电流大小;


图2
所以FOC里面由于svpwm中间的零矢量的存在,天生的产生了一个这样生产电流(0矢量),泵生电压(非0矢量)的过程,这就自然能把电流推到母线上去了



下面宏观看世界:
我们来看看一些物理公式!不喜欢看的不用往下看了,foc回充的本质原理上面的微观世界已经学会了!
<span class="MathJax_SVG" id="MathJax-Element-1-Frame" tabindex="0" data-mathml="Q&#x8F74;&#x7535;&#x538B;&#x65B9;&#x7A0B;&#xFF1A;Vq=Rs&#x22C5;Iq+Lq&#x22C5;Iq&#x2032;+we&#x22C5;Ld&#x22C5;Id+we&#x22C5;&#x03C8;f&#x2212;&#x2212;&#x2212;&#x2212;&#x2212;&#x516C;&#x5F0F;1" role="presentation" style="display: inline-block; line-height: normal; font-size: 16px; word-spacing: normal; overflow-wrap: normal; text-wrap: nowrap; float: none; direction: ltr; max-width: none; max-height: none; min-width: 0px; min-height: 0px; border: 0px; padding: 0px; margin: 0px; position: relative;">轴电压方程:公式�轴电压方程:��=��⋅��+��⋅��′+��⋅��⋅��+��⋅��−−−−−公式1
场景里面的描述,转速高到一定程度之后,电机不能再加速了,原因是上面这个电机的电压公式, <span class="MathJax_SVG" id="MathJax-Element-4-Frame" tabindex="0" data-mathml="we&#xA0;" role="presentation" style="display: inline-block; line-height: normal; font-size: 16px; word-spacing: normal; overflow-wrap: normal; text-wrap: nowrap; float: none; direction: ltr; max-width: none; max-height: none; min-width: 0px; min-height: 0px; border: 0px; padding: 0px; margin: 0px; position: relative;">��  很高,则 <span class="MathJax_SVG" id="MathJax-Element-3-Frame" tabindex="0" data-mathml="we&#x22C5;&#x03C8;f" role="presentation" style="display: inline-block; line-height: normal; font-size: 16px; word-spacing: normal; overflow-wrap: normal; text-wrap: nowrap; float: none; direction: ltr; max-width: none; max-height: none; min-width: 0px; min-height: 0px; border: 0px; padding: 0px; margin: 0px; position: relative;">��⋅�� 很大,当该值接近 <span class="MathJax_SVG" id="MathJax-Element-2-Frame" tabindex="0" data-mathml="Vq" role="presentation" style="display: inline-block; line-height: normal; font-size: 16px; word-spacing: normal; overflow-wrap: normal; text-wrap: nowrap; float: none; direction: ltr; max-width: none; max-height: none; min-width: 0px; min-height: 0px; border: 0px; padding: 0px; margin: 0px; position: relative;">�� 的最大值(是真实的物理世界,电压不可能无限制高)的时候,可以看出该等式的解要求 <span class="MathJax_SVG" id="MathJax-Element-5-Frame" tabindex="0" data-mathml="Id&#xFF0C;Iq" role="presentation" style="display: inline-block; line-height: normal; font-size: 16px; word-spacing: normal; overflow-wrap: normal; text-wrap: nowrap; float: none; direction: ltr; max-width: none; max-height: none; min-width: 0px; min-height: 0px; border: 0px; padding: 0px; margin: 0px; position: relative;">,��,�� 要求为0,q轴电流都为0了,电机自然就没有力矩去加速或者维持转速了,自然就没有办法继续升高速度了啊,
实际系统是<span class="MathJax_SVG" id="MathJax-Element-7-Frame" tabindex="0" data-mathml="we&#x22C5;&#x03C8;f" role="presentation" style="display: inline-block; line-height: normal; font-size: 16px; word-spacing: normal; overflow-wrap: normal; text-wrap: nowrap; float: none; direction: ltr; max-width: none; max-height: none; min-width: 0px; min-height: 0px; border: 0px; padding: 0px; margin: 0px; position: relative;">��⋅��很大,但是比<span class="MathJax_SVG" id="MathJax-Element-6-Frame" tabindex="0" data-mathml="Vq" role="presentation" style="display: inline-block; line-height: normal; font-size: 16px; word-spacing: normal; overflow-wrap: normal; text-wrap: nowrap; float: none; direction: ltr; max-width: none; max-height: none; min-width: 0px; min-height: 0px; border: 0px; padding: 0px; margin: 0px; position: relative;">��能给的最大值小一点,这样有个基本的 <span class="MathJax_SVG" id="MathJax-Element-10-Frame" tabindex="0" data-mathml="Iq" role="presentation" style="display: inline-block; line-height: normal; font-size: 16px; word-spacing: normal; overflow-wrap: normal; text-wrap: nowrap; float: none; direction: ltr; max-width: none; max-height: none; min-width: 0px; min-height: 0px; border: 0px; padding: 0px; margin: 0px; position: relative;">�� 电流在维持工作,而关于<span class="MathJax_SVG" id="MathJax-Element-9-Frame" tabindex="0" data-mathml="we&#x22C5;Ld&#x22C5;Id" role="presentation" style="display: inline-block; line-height: normal; font-size: 16px; word-spacing: normal; overflow-wrap: normal; text-wrap: nowrap; float: none; direction: ltr; max-width: none; max-height: none; min-width: 0px; min-height: 0px; border: 0px; padding: 0px; margin: 0px; position: relative;">��⋅��⋅�� 这项,因为我们控制了 <span class="MathJax_SVG" id="MathJax-Element-8-Frame" tabindex="0" data-mathml="Id" role="presentation" style="display: inline-block; line-height: normal; font-size: 16px; word-spacing: normal; overflow-wrap: normal; text-wrap: nowrap; float: none; direction: ltr; max-width: none; max-height: none; min-width: 0px; min-height: 0px; border: 0px; padding: 0px; margin: 0px; position: relative;">�� 为0,所以可以不看它了,
但是留心也会注意到,如果我们控制 <span class="MathJax_SVG" id="MathJax-Element-11-Frame" tabindex="0" data-mathml="Id" role="presentation" style="display: inline-block; line-height: normal; font-size: 16px; word-spacing: normal; overflow-wrap: normal; text-wrap: nowrap; float: none; direction: ltr; max-width: none; max-height: none; min-width: 0px; min-height: 0px; border: 0px; padding: 0px; margin: 0px; position: relative;">�� 为负值,那么可以看出该Q轴电压方程的解中,一样大的 <span class="MathJax_SVG" id="MathJax-Element-12-Frame" tabindex="0" data-mathml="Iq" role="presentation" style="display: inline-block; line-height: normal; font-size: 16px; word-spacing: normal; overflow-wrap: normal; text-wrap: nowrap; float: none; direction: ltr; max-width: none; max-height: none; min-width: 0px; min-height: 0px; border: 0px; padding: 0px; margin: 0px; position: relative;">�� 对应的<span class="MathJax_SVG" id="MathJax-Element-14-Frame" tabindex="0" data-mathml="we&#xA0;" role="presentation" style="display: inline-block; line-height: normal; font-size: 16px; word-spacing: normal; overflow-wrap: normal; text-wrap: nowrap; float: none; direction: ltr; max-width: none; max-height: none; min-width: 0px; min-height: 0px; border: 0px; padding: 0px; margin: 0px; position: relative;">�� 可以更高一点!这就是 我们常常说的弱磁提速,相应的如果<span class="MathJax_SVG" id="MathJax-Element-13-Frame" tabindex="0" data-mathml="Id" role="presentation" style="display: inline-block; line-height: normal; font-size: 16px; word-spacing: normal; overflow-wrap: normal; text-wrap: nowrap; float: none; direction: ltr; max-width: none; max-height: none; min-width: 0px; min-height: 0px; border: 0px; padding: 0px; margin: 0px; position: relative;">�� 为正值那么<span class="MathJax_SVG" id="MathJax-Element-15-Frame" tabindex="0" data-mathml="we&#xA0;" role="presentation" style="display: inline-block; line-height: normal; font-size: 16px; word-spacing: normal; overflow-wrap: normal; text-wrap: nowrap; float: none; direction: ltr; max-width: none; max-height: none; min-width: 0px; min-height: 0px; border: 0px; padding: 0px; margin: 0px; position: relative;">�� 就会变小一点了,这也就是我们常常如果d轴没有加pi控制器去控制电流为0,放任不管的情况下的现象,电机转速会偏慢;
看了这个电压方程,我们能更加确定这里的反电动势是不可能大过最大的电池电压了,但是我们可以看到,这里的<span class="MathJax_SVG" id="MathJax-Element-16-Frame" tabindex="0" data-mathml="Vq" role="presentation" style="display: inline-block; line-height: normal; font-size: 16px; word-spacing: normal; overflow-wrap: normal; text-wrap: nowrap; float: none; direction: ltr; max-width: none; max-height: none; min-width: 0px; min-height: 0px; border: 0px; padding: 0px; margin: 0px; position: relative;">��是我们控制器软件中实际给出来的,只要不超过最大的能给的电压值,我们控制软件都是能给的出来的,那么给不同的值,会出现什么情况呢?
实际给多大还是基于我们想要的<span class="MathJax_SVG" id="MathJax-Element-17-Frame" tabindex="0" data-mathml="Id&#xFF0C;Iq" role="presentation" style="display: inline-block; line-height: normal; font-size: 16px; word-spacing: normal; overflow-wrap: normal; text-wrap: nowrap; float: none; direction: ltr; max-width: none; max-height: none; min-width: 0px; min-height: 0px; border: 0px; padding: 0px; margin: 0px; position: relative;">,��,�� 电流,目的要维持这个等式左右平衡,如果想要的<span class="MathJax_SVG" id="MathJax-Element-19-Frame" tabindex="0" data-mathml="Id&#xFF0C;Iq" role="presentation" style="display: inline-block; line-height: normal; font-size: 16px; word-spacing: normal; overflow-wrap: normal; text-wrap: nowrap; float: none; direction: ltr; max-width: none; max-height: none; min-width: 0px; min-height: 0px; border: 0px; padding: 0px; margin: 0px; position: relative;">,��,�� 需要<span class="MathJax_SVG" id="MathJax-Element-18-Frame" tabindex="0" data-mathml="Vq" role="presentation" style="display: inline-block; line-height: normal; font-size: 16px; word-spacing: normal; overflow-wrap: normal; text-wrap: nowrap; float: none; direction: ltr; max-width: none; max-height: none; min-width: 0px; min-height: 0px; border: 0px; padding: 0px; margin: 0px; position: relative;">��是5V,但是你却偏偏要给6v,那么就是公式1的右边就会发生状态变化了<span class="MathJax_SVG" id="MathJax-Element-20-Frame" tabindex="0" data-mathml="we&#xA0;" role="presentation" style="display: inline-block; line-height: normal; font-size: 16px; word-spacing: normal; overflow-wrap: normal; text-wrap: nowrap; float: none; direction: ltr; max-width: none; max-height: none; min-width: 0px; min-height: 0px; border: 0px; padding: 0px; margin: 0px; position: relative;">�� 就不是原来的值了或者电流也不在是原来的值了,总之状态会发生变化;
接下来基于这个状态的平衡,我们继续看,我们都默认控制了<span class="MathJax_SVG" id="MathJax-Element-22-Frame" tabindex="0" data-mathml="Id" role="presentation" style="display: inline-block; line-height: normal; font-size: 16px; word-spacing: normal; overflow-wrap: normal; text-wrap: nowrap; float: none; direction: ltr; max-width: none; max-height: none; min-width: 0px; min-height: 0px; border: 0px; padding: 0px; margin: 0px; position: relative;">�� 为0,如果我控制了<span class="MathJax_SVG" id="MathJax-Element-25-Frame" tabindex="0" data-mathml="Vq" role="presentation" style="display: inline-block; line-height: normal; font-size: 16px; word-spacing: normal; overflow-wrap: normal; text-wrap: nowrap; float: none; direction: ltr; max-width: none; max-height: none; min-width: 0px; min-height: 0px; border: 0px; padding: 0px; margin: 0px; position: relative;">��比<span class="MathJax_SVG" id="MathJax-Element-24-Frame" tabindex="0" data-mathml="we&#x22C5;&#x03C8;f" role="presentation" style="display: inline-block; line-height: normal; font-size: 16px; word-spacing: normal; overflow-wrap: normal; text-wrap: nowrap; float: none; direction: ltr; max-width: none; max-height: none; min-width: 0px; min-height: 0px; border: 0px; padding: 0px; margin: 0px; position: relative;">��⋅��小,是不是就出现了负的<span class="MathJax_SVG" id="MathJax-Element-23-Frame" tabindex="0" data-mathml="Iq" role="presentation" style="display: inline-block; line-height: normal; font-size: 16px; word-spacing: normal; overflow-wrap: normal; text-wrap: nowrap; float: none; direction: ltr; max-width: none; max-height: none; min-width: 0px; min-height: 0px; border: 0px; padding: 0px; margin: 0px; position: relative;">��了,出现负的<span class="MathJax_SVG" id="MathJax-Element-21-Frame" tabindex="0" data-mathml="Iq" role="presentation" style="display: inline-block; line-height: normal; font-size: 16px; word-spacing: normal; overflow-wrap: normal; text-wrap: nowrap; float: none; direction: ltr; max-width: none; max-height: none; min-width: 0px; min-height: 0px; border: 0px; padding: 0px; margin: 0px; position: relative;">��有两种情况:
1.电机正向旋转,但是负的<span class="MathJax_SVG" id="MathJax-Element-26-Frame" tabindex="0" data-mathml="Iq" role="presentation" style="display: inline-block; line-height: normal; font-size: 16px; word-spacing: normal; overflow-wrap: normal; text-wrap: nowrap; float: none; direction: ltr; max-width: none; max-height: none; min-width: 0px; min-height: 0px; border: 0px; padding: 0px; margin: 0px; position: relative;">��,
2.电机负向旋转,也是负的<span class="MathJax_SVG" id="MathJax-Element-27-Frame" tabindex="0" data-mathml="Iq" role="presentation" style="display: inline-block; line-height: normal; font-size: 16px; word-spacing: normal; overflow-wrap: normal; text-wrap: nowrap; float: none; direction: ltr; max-width: none; max-height: none; min-width: 0px; min-height: 0px; border: 0px; padding: 0px; margin: 0px; position: relative;">��,
出现1的情况,<span class="MathJax_SVG" id="MathJax-Element-30-Frame" tabindex="0" data-mathml="Vq" role="presentation" style="display: inline-block; line-height: normal; font-size: 16px; word-spacing: normal; overflow-wrap: normal; text-wrap: nowrap; float: none; direction: ltr; max-width: none; max-height: none; min-width: 0px; min-height: 0px; border: 0px; padding: 0px; margin: 0px; position: relative;">��还有两种情况,电机正向旋转,<span class="MathJax_SVG" id="MathJax-Element-28-Frame" tabindex="0" data-mathml="we&#x22C5;&#x03C8;f" role="presentation" style="display: inline-block; line-height: normal; font-size: 16px; word-spacing: normal; overflow-wrap: normal; text-wrap: nowrap; float: none; direction: ltr; max-width: none; max-height: none; min-width: 0px; min-height: 0px; border: 0px; padding: 0px; margin: 0px; position: relative;">��⋅��是正的,1.负的<span class="MathJax_SVG" id="MathJax-Element-29-Frame" tabindex="0" data-mathml="Iq" role="presentation" style="display: inline-block; line-height: normal; font-size: 16px; word-spacing: normal; overflow-wrap: normal; text-wrap: nowrap; float: none; direction: ltr; max-width: none; max-height: none; min-width: 0px; min-height: 0px; border: 0px; padding: 0px; margin: 0px; position: relative;">��很大,这导致的<span class="MathJax_SVG" id="MathJax-Element-32-Frame" tabindex="0" data-mathml="Vq" role="presentation" style="display: inline-block; line-height: normal; font-size: 16px; word-spacing: normal; overflow-wrap: normal; text-wrap: nowrap; float: none; direction: ltr; max-width: none; max-height: none; min-width: 0px; min-height: 0px; border: 0px; padding: 0px; margin: 0px; position: relative;">��都为负的了;2.负的<span class="MathJax_SVG" id="MathJax-Element-33-Frame" tabindex="0" data-mathml="Iq" role="presentation" style="display: inline-block; line-height: normal; font-size: 16px; word-spacing: normal; overflow-wrap: normal; text-wrap: nowrap; float: none; direction: ltr; max-width: none; max-height: none; min-width: 0px; min-height: 0px; border: 0px; padding: 0px; margin: 0px; position: relative;">��一般大,这导致<span class="MathJax_SVG" id="MathJax-Element-31-Frame" tabindex="0" data-mathml="Vq" role="presentation" style="display: inline-block; line-height: normal; font-size: 16px; word-spacing: normal; overflow-wrap: normal; text-wrap: nowrap; float: none; direction: ltr; max-width: none; max-height: none; min-width: 0px; min-height: 0px; border: 0px; padding: 0px; margin: 0px; position: relative;">��还是正的!
出现2的情况,<span class="MathJax_SVG" id="MathJax-Element-34-Frame" tabindex="0" data-mathml="Vq" role="presentation" style="display: inline-block; line-height: normal; font-size: 16px; word-spacing: normal; overflow-wrap: normal; text-wrap: nowrap; float: none; direction: ltr; max-width: none; max-height: none; min-width: 0px; min-height: 0px; border: 0px; padding: 0px; margin: 0px; position: relative;">��只有为负的了,电机反向旋转,<span class="MathJax_SVG" id="MathJax-Element-35-Frame" tabindex="0" data-mathml="we&#x22C5;&#x03C8;f" role="presentation" style="display: inline-block; line-height: normal; font-size: 16px; word-spacing: normal; overflow-wrap: normal; text-wrap: nowrap; float: none; direction: ltr; max-width: none; max-height: none; min-width: 0px; min-height: 0px; border: 0px; padding: 0px; margin: 0px; position: relative;">��⋅��是负的,不管负的<span class="MathJax_SVG" id="MathJax-Element-36-Frame" tabindex="0" data-mathml="Iq" role="presentation" style="display: inline-block; line-height: normal; font-size: 16px; word-spacing: normal; overflow-wrap: normal; text-wrap: nowrap; float: none; direction: ltr; max-width: none; max-height: none; min-width: 0px; min-height: 0px; border: 0px; padding: 0px; margin: 0px; position: relative;">��多大,导致的<span class="MathJax_SVG" id="MathJax-Element-37-Frame" tabindex="0" data-mathml="Vq" role="presentation" style="display: inline-block; line-height: normal; font-size: 16px; word-spacing: normal; overflow-wrap: normal; text-wrap: nowrap; float: none; direction: ltr; max-width: none; max-height: none; min-width: 0px; min-height: 0px; border: 0px; padding: 0px; margin: 0px; position: relative;">��都为负的了!
负的<span class="MathJax_SVG" id="MathJax-Element-38-Frame" tabindex="0" data-mathml="Iq" role="presentation" style="display: inline-block; line-height: normal; font-size: 16px; word-spacing: normal; overflow-wrap: normal; text-wrap: nowrap; float: none; direction: ltr; max-width: none; max-height: none; min-width: 0px; min-height: 0px; border: 0px; padding: 0px; margin: 0px; position: relative;">��只能说明电机有和正向旋转方向相反的负向电磁力矩,但是并不能说明电机在回充电,什么时候电机在回充?
我们要从能量角度去看,
负的功率产生了,那就是在回充,电机里面功率怎么计算?<span class="MathJax_SVG" id="MathJax-Element-39-Frame" tabindex="0" data-mathml="P=Va&#x22C5;Ia+Vb&#x22C5;Ib+Vc&#x22C5;Ic=1.5&#xFF08;Vd&#x22C5;Id+Vq&#x22C5;Iq&#xFF09;=Vdc&#x22C5;Idc" role="presentation" style="display: inline-block; line-height: normal; font-size: 16px; word-spacing: normal; overflow-wrap: normal; text-wrap: nowrap; float: none; direction: ltr; max-width: none; max-height: none; min-width: 0px; min-height: 0px; border: 0px; padding: 0px; margin: 0px; position: relative;">()�=��⋅��+��⋅��+��⋅��=1.5(��⋅��+��⋅��)=���⋅��� ,这个好理解,电压乘以电流,加起来就是功率了,为什么是1.5的系数,大家记得网上流传的等功率变换的系数是 <span class="MathJax_SVG" id="MathJax-Element-41-Frame" tabindex="0" data-mathml="2/3" role="presentation" style="display: inline-block; line-height: normal; font-size: 16px; word-spacing: normal; overflow-wrap: normal; text-wrap: nowrap; float: none; direction: ltr; max-width: none; max-height: none; min-width: 0px; min-height: 0px; border: 0px; padding: 0px; margin: 0px; position: relative;">2/3 ,结合我链接文章的第3部分,可以知道等功率变换 <span class="MathJax_SVG" id="MathJax-Element-40-Frame" tabindex="0" data-mathml="m=2/3" role="presentation" style="display: inline-block; line-height: normal; font-size: 16px; word-spacing: normal; overflow-wrap: normal; text-wrap: nowrap; float: none; direction: ltr; max-width: none; max-height: none; min-width: 0px; min-height: 0px; border: 0px; padding: 0px; margin: 0px; position: relative;">�=2/3
SVPWM调制中的6个非零基础电压矢量的幅值到底是Udc还是2/3Udc ? 电压利用率为什么是1?clark变换的系数?879 赞同 · 160 评论文章
于是可以知道 <span class="MathJax_SVG" id="MathJax-Element-44-Frame" tabindex="0" data-mathml="1.5=3/2&#x2217;3/2&#x2217;2/3&#x2217;2/3" role="presentation" style="display: inline-block; line-height: normal; font-size: 16px; word-spacing: normal; overflow-wrap: normal; text-wrap: nowrap; float: none; direction: ltr; max-width: none; max-height: none; min-width: 0px; min-height: 0px; border: 0px; padding: 0px; margin: 0px; position: relative;">1.5=3/2∗3/2∗2/3∗2/3
于是我们知道怎么才能有母线的回充电流?是不是只要 <span class="MathJax_SVG" id="MathJax-Element-43-Frame" tabindex="0" data-mathml="Idc" role="presentation" style="display: inline-block; line-height: normal; font-size: 16px; word-spacing: normal; overflow-wrap: normal; text-wrap: nowrap; float: none; direction: ltr; max-width: none; max-height: none; min-width: 0px; min-height: 0px; border: 0px; padding: 0px; margin: 0px; position: relative;">��� 为负值,就表示向电池里面冲入电流了?而 <span class="MathJax_SVG" id="MathJax-Element-45-Frame" tabindex="0" data-mathml="Vdc" role="presentation" style="display: inline-block; line-height: normal; font-size: 16px; word-spacing: normal; overflow-wrap: normal; text-wrap: nowrap; float: none; direction: ltr; max-width: none; max-height: none; min-width: 0px; min-height: 0px; border: 0px; padding: 0px; margin: 0px; position: relative;">���一直是正的,这里 <span class="MathJax_SVG" id="MathJax-Element-42-Frame" tabindex="0" data-mathml="Id=0" role="presentation" style="display: inline-block; line-height: normal; font-size: 16px; word-spacing: normal; overflow-wrap: normal; text-wrap: nowrap; float: none; direction: ltr; max-width: none; max-height: none; min-width: 0px; min-height: 0px; border: 0px; padding: 0px; margin: 0px; position: relative;">��=0 所以我们要 <span class="ztext-math" data-eeimg="1" data-tex="V_{q}\cdot I_{q} <span class="MathJax_SVG" id="MathJax-Element-46-Frame" tabindex="0" data-mathml="Vq&#x22C5;Iq&lt;0" role="presentation" style="display: inline-block; line-height: normal; font-size: 16px; word-spacing: normal; overflow-wrap: normal; text-wrap: nowrap; float: none; direction: ltr; max-width: none; max-height: none; min-width: 0px; min-height: 0px; border: 0px; padding: 0px; margin: 0px; position: relative;">��⋅��<0 则就能保证<span class="MathJax_SVG" id="MathJax-Element-47-Frame" tabindex="0" data-mathml="Idc" role="presentation" style="display: inline-block; line-height: normal; font-size: 16px; word-spacing: normal; overflow-wrap: normal; text-wrap: nowrap; float: none; direction: ltr; max-width: none; max-height: none; min-width: 0px; min-height: 0px; border: 0px; padding: 0px; margin: 0px; position: relative;">��� 为负值了,这就要求 <span class="MathJax_SVG" id="MathJax-Element-49-Frame" tabindex="0" data-mathml="Vq&#x548C;Iq&#x5F02;&#x53F7;" role="presentation" style="display: inline-block; line-height: normal; font-size: 16px; word-spacing: normal; overflow-wrap: normal; text-wrap: nowrap; float: none; direction: ltr; max-width: none; max-height: none; min-width: 0px; min-height: 0px; border: 0px; padding: 0px; margin: 0px; position: relative;">和异号��和��异号 !
所以能有回充的充要条件就是要让<span class="MathJax_SVG" id="MathJax-Element-48-Frame" tabindex="0" data-mathml="Vq&#x548C;Iq&#x5F02;&#x53F7;" role="presentation" style="display: inline-block; line-height: normal; font-size: 16px; word-spacing: normal; overflow-wrap: normal; text-wrap: nowrap; float: none; direction: ltr; max-width: none; max-height: none; min-width: 0px; min-height: 0px; border: 0px; padding: 0px; margin: 0px; position: relative;">和异号��和��异号!(id = 0的前提下)
Vq大于0且小于反电动势(正向旋转,反电动势 正值),能保证产生负的iq,这就保证了功率是负的,
Vq小于0且大于反电动势(反向旋转,反电动势 负值),能保证产生正的iq,这就也保证了功率是负的,
这就都保证了电流能回充到电池里面去了,
Vq大于0且大于反电动势(正向旋转,反电动势 正值),能保证产生正的iq,这就保证了功率是正的,
Vq小于0且小于反电动势(反向旋转,反电动势 负值),能保证产生负的iq,这就也保证了功率是正的,
这就都保证了电流要从电池里面抽出来了,
好了,先到这了,还没校对,可能有错别字,后面看有木有再要补充的。。。。。。。。。。。。。
20201215修改顺序,避免上来公式;
20230310插入过调制的章节;





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