等离子体诊断方法-第一章：静电探针 以某磁重联实验为例，简单讨论了静电三探针与磁探针在等离子体诊断中的应用。

基于Libnids的网络安全审计系统 本文章旨在记录课程《网络空间信息安全》最终大作业——“网络安全审计系统”的初步实现以及思路。同时介绍了构造HTTP、FTP以及SMTP数据包的方法。如果认真学习该课程将对该文章过程不会产生原则性疑问。项目上传到核学院共享平台仓库

AfterParty {bilibili bvid="BV1Mm4y1S7GU" page=""/}

基于UC3842的Boost升压电路 html {overflow-x: initial !important;}:root { --bg-color: #ffffff; --text-color: #333333; --select-text-bg-color: #B5D6FC; --select-text-font-color: auto; --monospace: "Lucida Console",Consolas,"Courier",monospace; --title-bar-height: 20px; } .mac-os-11 { --title-bar-height: 28px; } html { font-size: 14px; background-color: var(--bg-color); color: var(--text-color); font-family: "Helvetica Neue", Helvetica, Arial, sans-serif; -webkit-font-smoothing: antialiased; } body { margin: 0px; padding: 0px; height: auto; inset: 0px; font-size: 1rem; line-height: 1.42857143; overflow-x: hidden; background-image: inherit; background-size: inherit; background-attachment: inherit; background-origin: inherit; background-clip: inherit; background-color: inherit; tab-size: 4; background-position: inherit; background-repeat: inherit; } iframe { margin: auto; } a.url { word-break: break-all; } a:active, a:hover { outline: 0px; } .in-text-selection, ::selection { text-shadow: none; background: var(--select-text-bg-color); color: var(--select-text-font-color); } #write { margin: 0px auto; height: auto; width: inherit; word-break: normal; word-wrap: break-word; position: relative; white-space: normal; overflow-x: visible; padding-top: 36px; } #write.first-line-indent p { text-indent: 2em; } #write.first-line-indent li p, #write.first-line-indent p * { text-indent: 0px; } #write.first-line-indent li { margin-left: 2em; } .for-image #write { padding-left: 8px; padding-right: 8px; } body.typora-export { padding-left: 30px; padding-right: 30px; } .typora-export .footnote-line, .typora-export li, .typora-export p { white-space: pre-wrap; } .typora-export .task-list-item input { pointer-events: none; } @media screen and (max-width: 500px) {    body.typora-export { padding-left: 0px; padding-right: 0px; }   #write { padding-left: 20px; padding-right: 20px; }   .CodeMirror-sizer { margin-left: 0px !important; }   .CodeMirror-gutters { display: none !important; } } #write li > figure:last-child { margin-bottom: 0.5rem; } #write ol, #write ul { position: relative; } img { max-width: 100%; vertical-align: middle; image-orientation: from-image; } button, input, select, textarea { color: inherit; font-family: inherit; font-size: inherit; font-style: inherit; font-variant-caps: inherit; font-weight: inherit; font-stretch: inherit; line-height: inherit; } input[type="checkbox"], input[type="radio"] { line-height: normal; padding: 0px; } *, ::after, ::before { box-sizing: border-box; } #write h1, #write h2, #write h3, #write h4, #write h5, #write h6, #write p, #write pre { width: inherit; } #write h1, #write h2, #write h3, #write h4, #write h5, #write h6, #write p { position: relative; } p { line-height: inherit; } h1, h2, h3, h4, h5, h6 { break-after: avoid-page; break-inside: avoid; orphans: 4; } p { orphans: 4; } h1 { font-size: 2rem; } h2 { font-size: 1.8rem; } h3 { font-size: 1.6rem; } h4 { font-size: 1.4rem; } h5 { font-size: 1.2rem; } h6 { font-size: 1rem; } .md-math-block, .md-rawblock, h1, h2, h3, h4, h5, h6, p { margin-top: 1rem; margin-bottom: 1rem; } .hidden { display: none; } .md-blockmeta { color: rgb(204, 204, 204); font-weight: 700; font-style: italic; } a { cursor: pointer; } sup.md-footnote { padding: 2px 4px; background-color: rgba(238, 238, 238, 0.7); color: rgb(85, 85, 85); border-top-left-radius: 4px; border-top-right-radius: 4px; border-bottom-right-radius: 4px; border-bottom-left-radius: 4px; cursor: pointer; } sup.md-footnote a, sup.md-footnote a:hover { color: inherit; text-transform: inherit; text-decoration: inherit; } #write input[type="checkbox"] { cursor: pointer; width: inherit; height: inherit; } figure { overflow-x: auto; margin: 1.2em 0px; max-width: calc(100% + 16px); padding: 0px; } figure > table { margin: 0px; } tr { break-inside: avoid; break-after: auto; } thead { display: table-header-group; } table { border-collapse: collapse; border-spacing: 0px; width: 100%; overflow: auto; break-inside: auto; text-align: left; } table.md-table td { min-width: 32px; } .CodeMirror-gutters { border-right-width: 0px; background-color: inherit; } .CodeMirror-linenumber { } .CodeMirror { text-align: left; } .CodeMirror-placeholder { opacity: 0.3; } .CodeMirror pre { padding: 0px 4px; } .CodeMirror-lines { padding: 0px; } div.hr:focus { cursor: none; } #write pre { white-space: pre-wrap; } #write.fences-no-line-wrapping pre { white-space: pre; } #write pre.ty-contain-cm { white-space: normal; } .CodeMirror-gutters { margin-right: 4px; } .md-fences { font-size: 0.9rem; display: block; break-inside: avoid; text-align: left; overflow: visible; white-space: pre; background-image: inherit; background-size: inherit; background-attachment: inherit; background-origin: inherit; background-clip: inherit; background-color: inherit; position: relative !important; background-position: inherit; background-repeat: inherit; } .md-fences-adv-panel { width: 100%; margin-top: 10px; text-align: center; padding-top: 0px; padding-bottom: 8px; overflow-x: auto; } #write .md-fences.mock-cm { white-space: pre-wrap; } .md-fences.md-fences-with-lineno { padding-left: 0px; } #write.fences-no-line-wrapping .md-fences.mock-cm { white-space: pre; overflow-x: auto; } .md-fences.mock-cm.md-fences-with-lineno { padding-left: 8px; } .CodeMirror-line, twitterwidget { break-inside: avoid; } .footnotes { opacity: 0.8; font-size: 0.9rem; margin-top: 1em; margin-bottom: 1em; } .footnotes + .footnotes { margin-top: 0px; } .md-reset { margin: 0px; padding: 0px; border: 0px; outline: 0px; vertical-align: top; text-decoration: none; text-shadow: none; float: none; position: static; width: auto; height: auto; white-space: nowrap; cursor: inherit; line-height: normal; font-weight: 400; text-align: left; box-sizing: content-box; direction: ltr; background-position: 0px 0px; } li div { padding-top: 0px; } blockquote { margin: 1rem 0px; } li .mathjax-block, li p { margin: 0.5rem 0px; } li blockquote { margin: 1rem 0px; } li { margin: 0px; position: relative; } blockquote > :last-child { margin-bottom: 0px; } blockquote > :first-child, li > :first-child { margin-top: 0px; } .footnotes-area { color: rgb(136, 136, 136); margin-top: 0.714rem; padding-bottom: 0.143rem; white-space: normal; } #write .footnote-line { white-space: pre-wrap; } @media print {    body, html { border: 1px solid transparent; height: 99%; break-after: avoid; break-before: avoid; font-variant-ligatures: no-common-ligatures; }   #write { margin-top: 0px; padding-top: 0px; border-color: transparent !important; }   .typora-export * { -webkit-print-color-adjust: exact; }   .typora-export #write { break-after: avoid; }   .typora-export #write::after { height: 0px; }   .is-mac table { break-inside: avoid; }   .typora-export-show-outline .typora-export-sidebar { display: none; } } .footnote-line { margin-top: 0.714em; font-size: 0.7em; } a img, img a { cursor: pointer; } pre.md-meta-block { font-size: 0.8rem; min-height: 0.8rem; white-space: pre-wrap; background-color: rgb(204, 204, 204); display: block; overflow-x: hidden; } p > .md-image:only-child:not(.md-img-error) img, p > img:only-child { display: block; margin: auto; } #write.first-line-indent p > .md-image:only-child:not(.md-img-error) img { left: -2em; position: relative; } p > .md-image:only-child { display: inline-block; width: 100%; } #write .MathJax_Display { margin: 0.8em 0px 0px; } .md-math-block { width: 100%; } .md-math-block:not(:empty)::after { display: none; } .MathJax_ref { fill: currentcolor; } [contenteditable="true"]:active, [contenteditable="true"]:focus, [contenteditable="false"]:active, [contenteditable="false"]:focus { outline: 0px; box-shadow: none; } .md-task-list-item { position: relative; list-style-type: none; } .task-list-item.md-task-list-item { padding-left: 0px; } .md-task-list-item > input { position: absolute; top: 0px; left: 0px; margin-left: -1.2em; margin-top: calc(1em - 10px); border: none; } .math { font-size: 1rem; } .md-toc { min-height: 3.58rem; position: relative; font-size: 0.9rem; border-top-left-radius: 10px; border-top-right-radius: 10px; border-bottom-right-radius: 10px; border-bottom-left-radius: 10px; } .md-toc-content { position: relative; margin-left: 0px; } .md-toc-content::after, .md-toc::after { display: none; } .md-toc-item { display: block; color: rgb(65, 131, 196); } .md-toc-item a { text-decoration: none; } .md-toc-inner:hover { text-decoration: underline; } .md-toc-inner { display: inline-block; cursor: pointer; } .md-toc-h1 .md-toc-inner { margin-left: 0px; font-weight: 700; } .md-toc-h2 .md-toc-inner { margin-left: 2em; } .md-toc-h3 .md-toc-inner { margin-left: 4em; } .md-toc-h4 .md-toc-inner { margin-left: 6em; } .md-toc-h5 .md-toc-inner { margin-left: 8em; } .md-toc-h6 .md-toc-inner { margin-left: 10em; } @media screen and (max-width: 48em) {    .md-toc-h3 .md-toc-inner { margin-left: 3.5em; }   .md-toc-h4 .md-toc-inner { margin-left: 5em; }   .md-toc-h5 .md-toc-inner { margin-left: 6.5em; }   .md-toc-h6 .md-toc-inner { margin-left: 8em; } } a.md-toc-inner { font-size: inherit; font-style: inherit; font-weight: inherit; line-height: inherit; } .footnote-line a:not(.reversefootnote) { color: inherit; } .md-attr { display: none; } .md-fn-count::after { content: "."; } code, pre, samp, tt { font-family: var(--monospace); } kbd { margin: 0px 0.1em; padding: 0.1em 0.6em; font-size: 0.8em; color: rgb(36, 39, 41); background-color: rgb(255, 255, 255); border: 1px solid rgb(173, 179, 185); border-top-left-radius: 3px; border-top-right-radius: 3px; border-bottom-right-radius: 3px; border-bottom-left-radius: 3px; box-shadow: rgba(12, 13, 14, 0.2) 0px 1px 0px, rgb(255, 255, 255) 0px 0px 0px 2px inset; white-space: nowrap; vertical-align: middle; } .md-comment { color: rgb(162, 127, 3); opacity: 0.6; font-family: var(--monospace); } code { text-align: left; } a.md-print-anchor { white-space: pre !important; border: none !important; display: inline-block !important; position: absolute !important; width: 1px !important; right: 0px !important; outline: 0px !important; text-shadow: initial !important; background-position: 0px 0px !important; } .os-windows.monocolor-emoji .md-emoji { font-family: "Segoe UI Symbol", sans-serif; } .md-diagram-panel > svg { max-width: 100%; } [lang="flow"] svg, [lang="mermaid"] svg { max-width: 100%; height: auto; } [lang="mermaid"] .node text { font-size: 1rem; } table tr th { border-bottom-width: 0px; } video { max-width: 100%; display: block; margin: 0px auto; } iframe { max-width: 100%; width: 100%; border: none; } .highlight td, .highlight tr { border: 0px; } mark { background-color: rgb(255, 255, 0); color: rgb(0, 0, 0); } .md-html-inline .md-plain, .md-html-inline strong, mark .md-inline-math, mark strong { color: inherit; } .md-expand mark .md-meta { opacity: 0.3 !important; } mark .md-meta { color: rgb(0, 0, 0); } @media print {    .typora-export h1, .typora-export h2, .typora-export h3, .typora-export h4, .typora-export h5, .typora-export h6 { break-inside: avoid; } } .md-diagram-panel .messageText { stroke: none !important; } .md-diagram-panel .start-state { fill: var(--node-fill); } .md-diagram-panel .edgeLabel rect { opacity: 1 !important; } .md-fences.md-fences-math { font-size: 1em; } .md-fences-advanced:not(.md-focus) { padding: 0px; white-space: nowrap; border: 0px; } .md-fences-advanced:not(.md-focus) { background-image: inherit; background-size: inherit; background-attachment: inherit; background-origin: inherit; background-clip: inherit; background-color: inherit; background-position: inherit; background-repeat: inherit; } .typora-export-show-outline .typora-export-content { max-width: 1440px; margin: auto; display: flex; flex-direction: row; } .typora-export-sidebar { width: 300px; font-size: 0.8rem; margin-top: 80px; margin-right: 18px; } .typora-export-show-outline #write { --webkit-flex: 2; flex: 2 1 0%; } .typora-export-sidebar .outline-content { position: fixed; top: 0px; max-height: 100%; overflow: hidden auto; padding-bottom: 30px; padding-top: 60px; width: 300px; } @media screen and (max-width: 1024px) {    .typora-export-sidebar, .typora-export-sidebar .outline-content { width: 240px; } } @media screen and (max-width: 800px) {    .typora-export-sidebar { display: none; } } .outline-content li, .outline-content ul { margin-left: 0px; margin-right: 0px; padding-left: 0px; padding-right: 0px; list-style: none; } .outline-content ul { margin-top: 0px; margin-bottom: 0px; } .outline-content strong { font-weight: 400; } .outline-expander { width: 1rem; height: 1.428571429rem; position: relative; display: table-cell; vertical-align: middle; cursor: pointer; padding-left: 4px; } .outline-expander::before { content: ""; position: relative; font-family: Ionicons; display: inline-block; font-size: 8px; vertical-align: middle; } .outline-item { padding-top: 3px; padding-bottom: 3px; cursor: pointer; } .outline-expander:hover::before { content: ""; } .outline-h1 > .outline-item { padding-left: 0px; } .outline-h2 > .outline-item { padding-left: 1em; } .outline-h3 > .outline-item { padding-left: 2em; } .outline-h4 > .outline-item { padding-left: 3em; } .outline-h5 > .outline-item { padding-left: 4em; } .outline-h6 > .outline-item { padding-left: 5em; } .outline-label { cursor: pointer; display: table-cell; vertical-align: middle; text-decoration: none; color: inherit; } .outline-label:hover { text-decoration: underline; } .outline-item:hover { border-color: rgb(245, 245, 245); background-color: var(--item-hover-bg-color); } .outline-item:hover { margin-left: -28px; margin-right: -28px; border-left-width: 28px; border-left-style: solid; border-left-color: transparent; border-right-width: 28px; border-right-style: solid; border-right-color: transparent; } .outline-item-single .outline-expander::before, .outline-item-single .outline-expander:hover::before { display: none; } .outline-item-open > .outline-item > .outline-expander::before { content: ""; } .outline-children { display: none; } .info-panel-tab-wrapper { display: none; } .outline-item-open > .outline-children { display: block; } .typora-export .outline-item { padding-top: 1px; padding-bottom: 1px; } .typora-export .outline-item:hover { margin-right: -8px; border-right-width: 8px; border-right-style: solid; border-right-color: transparent; } .typora-export .outline-expander::before { content: "+"; font-family: inherit; top: -1px; } .typora-export .outline-expander:hover::before, .typora-export .outline-item-open > .outline-item > .outline-expander::before { content: "−"; } .typora-export-collapse-outline .outline-children { display: none; } .typora-export-collapse-outline .outline-item-open > .outline-children, .typora-export-no-collapse-outline .outline-children { display: block; } .typora-export-no-collapse-outline .outline-expander::before { content: "" !important; } .typora-export-show-outline .outline-item-active > .outline-item .outline-label { font-weight: 700; } .md-inline-math-container mjx-container { zoom: 0.95; } :root {     --side-bar-bg-color: #fafafa;     --control-text-color: #777; } @include-when-export url(https://fonts.loli.net/css?family=Open+Sans:400italic,700italic,700,400&subset=latin,latin-ext); /* open-sans-regular - latin-ext_latin */   /* open-sans-italic - latin-ext_latin */     /* open-sans-700 - latin-ext_latin */     /* open-sans-700italic - latin-ext_latin */   html {     font-size: 16px;     -webkit-font-smoothing: antialiased; } body {     font-family: "Open Sans","Clear Sans", "Helvetica Neue", Helvetica, Arial, 'Segoe UI Emoji', sans-serif;     color: rgb(51, 51, 51);     line-height: 1.6; } #write {     max-width: 860px;   margin: 0 auto;   padding: 30px;     padding-bottom: 100px; } @media only screen and (min-width: 1400px) { #write { max-width: 1024px; } } @media only screen and (min-width: 1800px) { #write { max-width: 1200px; } } #write > ul:first-child, #write > ol:first-child{     margin-top: 30px; } a {     color: #4183C4; } h1, h2, h3, h4, h5, h6 {     position: relative;     margin-top: 1rem;     margin-bottom: 1rem;     font-weight: bold;     line-height: 1.4;     cursor: text; } h1:hover a.anchor, h2:hover a.anchor, h3:hover a.anchor, h4:hover a.anchor, h5:hover a.anchor, h6:hover a.anchor {     text-decoration: none; } h1 tt, h1 code {     font-size: inherit; } h2 tt, h2 code {     font-size: inherit; } h3 tt, h3 code {     font-size: inherit; } h4 tt, h4 code {     font-size: inherit; } h5 tt, h5 code {     font-size: inherit; } h6 tt, h6 code {     font-size: inherit; } h1 {     font-size: 2.25em;     line-height: 1.2;     border-bottom: 1px solid #eee; } h2 {     font-size: 1.75em;     line-height: 1.225;     border-bottom: 1px solid #eee; } /*@media print {     .typora-export h1,     .typora-export h2 {         border-bottom: none;         padding-bottom: initial;     }     .typora-export h1::after,     .typora-export h2::after {         content: "";         display: block;         height: 100px;         margin-top: -96px;         border-top: 1px solid #eee;     } }*/ h3 {     font-size: 1.5em;     line-height: 1.43; } h4 {     font-size: 1.25em; } h5 {     font-size: 1em; } h6 {    font-size: 1em;     color: #777; } p, blockquote, ul, ol, dl, table{     margin: 0.8em 0; } li>ol, li>ul {     margin: 0 0; } hr {     height: 2px;     padding: 0;     margin: 16px 0;     background-color: #e7e7e7;     border: 0 none;     overflow: hidden;     box-sizing: content-box; } li p.first {     display: inline-block; } ul, ol {     padding-left: 30px; } ul:first-child, ol:first-child {     margin-top: 0; } ul:last-child, ol:last-child {     margin-bottom: 0; } blockquote {     border-left: 4px solid #dfe2e5;     padding: 0 15px;     color: #777777; } blockquote blockquote {     padding-right: 0; } table {     padding: 0;     word-break: initial; } table tr {     border: 1px solid #dfe2e5;     margin: 0;     padding: 0; } table tr:nth-child(2n), thead {     background-color: #f8f8f8; } table th {     font-weight: bold;     border: 1px solid #dfe2e5;     border-bottom: 0;     margin: 0;     padding: 6px 13px; } table td {     border: 1px solid #dfe2e5;     margin: 0;     padding: 6px 13px; } table th:first-child, table td:first-child {     margin-top: 0; } table th:last-child, table td:last-child {     margin-bottom: 0; } .CodeMirror-lines {     padding-left: 4px; } .code-tooltip {     box-shadow: 0 1px 1px 0 rgba(0,28,36,.3);     border-top: 1px solid #eef2f2; } .md-fences, code, tt {     border: 1px solid #e7eaed;     background-color: #f8f8f8;     border-radius: 3px;     padding: 0;     padding: 2px 4px 0px 4px;     font-size: 0.9em; } code {     background-color: #f3f4f4;     padding: 0 2px 0 2px; } .md-fences {     margin-bottom: 15px;     margin-top: 15px;     padding-top: 8px;     padding-bottom: 6px; } .md-task-list-item > input {   margin-left: -1.3em; } @media print {     html {         font-size: 13px;     }     table,     pre {         page-break-inside: avoid;     }     pre {         word-wrap: break-word;     } } .md-fences { background-color: #f8f8f8; } #write pre.md-meta-block { padding: 1rem;     font-size: 85%;     line-height: 1.45;     background-color: #f7f7f7;     border: 0;     border-radius: 3px;     color: #777777;     margin-top: 0 !important; } .mathjax-block>.code-tooltip { bottom: .375rem; } .md-mathjax-midline {     background: #fafafa; } #write>h3.md-focus:before{ left: -1.5625rem; top: .375rem; } #write>h4.md-focus:before{ left: -1.5625rem; 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} .mac-seamless-mode #typora-sidebar {     background-color: #fafafa;     background-color: var(--side-bar-bg-color); } .md-lang {     color: #b4654d; } /*.html-for-mac {     --item-hover-bg-color: #E6F0FE; }*/ #md-notification .btn {     border: 0; } .dropdown-menu .divider {     border-color: #e5e5e5;     opacity: 0.4; } .ty-preferences .window-content {     background-color: #fafafa; } .ty-preferences .nav-group-item.active {     color: white;     background: #999; } .menu-item-container a.menu-style-btn {     background-color: #f5f8fa;     background-image: linear-gradient( 180deg , hsla(0, 0%, 100%, 0.8), hsla(0, 0%, 100%, 0));  } mjx-container[jax="SVG"] {   direction: ltr; } mjx-container[jax="SVG"] > svg {   overflow: visible;   min-height: 1px;   min-width: 1px; } mjx-container[jax="SVG"] > svg a {   fill: blue;   stroke: blue; } mjx-assistive-mml {   position: absolute !important;   top: 0px;   left: 0px;   clip: rect(1px, 1px, 1px, 1px);   padding: 1px 0px 0px 0px !important; 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  line-height: normal;   overflow: visible; } mjx-container[jax="SVG"] path[data-c], mjx-container[jax="SVG"] use[data-c] {   stroke-width: 3; } g[data-mml-node="xypic"] path {   stroke-width: inherit; } .MathJax g[data-mml-node="xypic"] path {   stroke-width: inherit; } mjx-container[jax="SVG"] path[data-c], mjx-container[jax="SVG"] use[data-c] { stroke-width: 0; } @media print { @page {margin: 0 0 0 0;} body.typora-export {padding-left: 0; padding-right: 0;} #write {padding:0;}} 电赛 设计任务设计并制作图 1 所示的三相 AC-DC 变换电路，该电路的直流输出电压 Uo 应稳定在 36V，直流输出电流 Io 额定值为 2A。方案论证1.题目解析题目要求在不限制变压器具体工作特性的情况下，通过改变变压器输出线电压UiU_i,使得AC-DC变换电路输出稳定的36V电压，且此时额定电流为2A。同时需要满足稳定、负载变动率低、效率高、功率因数高等特性。为此，AC-DC变换部分应该选择三相可控整流电路，方便我们对整体电路等功率因数进行调控。同时，由于AC-DC变换在滤波良好的情况下会损失电压，无法达到36V的目的。还需要在AC-DC转换后添加DC-DC或DC-AC-DC变流电路。且需要保证电路输出各项参数指标保持相对稳定。2.方案选择与比较1.AC-DC-DCAC-DC-DC是将三相交流电整流为直流电后，再通过DC-DC变流电路将其调整为目标输出。其结构与达成方式较为简单。通过已有资源选定了使用UC3842驱动的Boost升压电路。其具有较强的稳压能力与较高的输出功率。缺点在于功能简陋，可调性不高，拓展性不强2.开关电源模式一个开关模式功率（SWP）变流器将一个(通常）固定值的直流电压转换成为一个可调节的直流输出电压。通过改变半导体开关器件的占空比可以实现对电压的控制，必须要使用一个隔离变压器。DC-DC 变流器的开关频率可以远远高于线频率，因此能使滤波器件，包括变压器在内都更小、更轻、效益更高，而且成本更低。变压器的输出被整流、滤波后得到一平滑的输出电压 V。可以用一个电压反馈控制回路来调节输出电压，这个回路采用了 PWM 开关技术。但是操作难度较大，周围为准备此类器件。综上所属，选择方案一方式。电路理论计算与设计三相整流电路设计1、三相不可控整流电路三相不可控整流电路采用阴极连接起来的三只二极管组成共阴级组，阳级连接在一起的三只二极管组成共阳极组。即构成六脉冲整流电路。整流电路的平均值表示为Ud=3π∫π32π32U21sinωtd(ωt)=1.35U21=2.34U2U_d=\frac3{\pi}\int_{\frac\pi3}^{\frac{2\pi}3}\sqrt{2}U_{21}sin\omega t d(\omega t)=1.35U_{21}=2.34U_{2}2、三相可控整流电路若将普通二极管置换为可控二极管，通过控制触发角可以起到控输出电压波形的作用。同时，通过调整触发角可以有效的控制整个的电路的功率因数范围。在时间和设备允许的条件下，将考虑将不可控整流电路设计更改为可控整流电路。 DC-DC升压电路设计设计DC-DC升压变流。需要将AC-DC转换断输出电压（约20V）得到36V，2A的恒定输出。总功率达到72W。因此考虑基于UC3842的BOOST升压电路。 电路的技术指标为：输入Vi=18VV_i=18V，输出Vo=36V,Io=2AV_o=36V,I_o=2A。频率f=100kHzf=100kHz。1.电感设计根据输入电压和输出电压确定最大占空比。Dmax=Vo−ViVo=36−2036=0.44D_{max}=\frac{V_o-V_i}{V_o}=\frac{36-20}{36}=0.44当输出最大负载时至少应满足电路工作在CCM模式下：L≥2(Vi−Vs)D(1−D)Iof=2×(20−0.9)×0.44×(1−0.44)2×49000=171μHL\ge\frac{2(V_i-V_s)D(1-D)}{I_of}=\frac{2\times(20-0.9)\times0.44\times(1-0.44)}{2\times49000}=171\mu H同时考虑在10%10\%额定负载以上电流连续的情况。一般情况下，可以假定电路在额定输出时电感纹波电流为平均电流的20%20\%至30%30\%，因此增加电感器电流纹波可以减小电感，但又为不增加输出纹波电压需要增大输出电容，取30%30\%为平衡点：ΔIL=30%×IL(ave)=30%×Io1−D=30%×21−0.44=1.07A\Delta I_L=30\%\times I_{L(ave)}=30\%\times\frac{I_o}{1-D}=30\%\times \frac{2}{1-0.44}=1.07A则L=(Vi−Vs)DILf=(20−0.9)×0.551.07×49000=200μHL=\frac{(V_i-V_s)D}{I_Lf}=\frac{(20-0.9)\times 0.55}{1.07\times49000}=200\mu H通过电感的峰值电流为：ILP=IL(ave)+ΔIL2=1.15×Io1−D=1.15×21−0.44=4.12AI_{LP}=I_{L(ave)}+\frac{\Delta I_L}{2}=1.15\times \frac{I_o}{1-D}=1.15\times\frac{2}{1-0.44}=4.12A则电感应选择电感量大于200μH200\mu H且可以通过4A4A以上电流不会饱和。2.输出电压取样电阻的选择UC3842的脚2为误差放大器的反向输入端，芯片内正向输入端端基准为2.5V，可知输出电压Vo=2.5×(1+R1R2)V_o=2.5\times(1+\frac{R1}{R2}),根据输出电压可以确定取样电阻R1、R2的取值。同时，由于电感的作用，在开关管开启和关闭时会形成的啊的尖顶电流，令检测电阻产生一个尖顶脉冲。为了防止误操作应此在取样点与脚3间加入RC滤波电路。时间常数与尖峰时间相同。3.开关管的选择开关管的电流由电感分析可以得到：Imax=ILP=4.12AI_{max}=I_{LP}=4.12A开关耐压值为：Vdsoff=Vo+Vf=36+0.8=36.8VVds_{off}=V_o+V_f=36+0.8=36.8V按照20%20 \%余量可以选择5A/45V5A/45V以上的开关管。4.输出二极管D与输出电容器C2升压电路中输出二极管D必须承受和输出电压等值的反向电压、并且需要传导负载所需的最大电流。即满足、Imax=4.12A、Vdsoff=36.8VI_{max}=4.12A、Vds_{off}=36.8V，选用5A/45V5A/45V以上的快恢复二极管。对于输出电容，其选定取决于对输出纹波电压的要求。纹波电压与电容的等效串联电阻ESR有关，电容器的容许纹波电流要大于电路中的纹波电流。需要满足ESR<ΔVoΔIL=36×1%1.07=0.34ΩESR