本文選題：多端口 + 級聯(lián)型固態(tài)變壓器��； 參考：《湖南大學(xué)》2016年碩士論文

【摘要】：隨著國內(nèi)外經(jīng)濟(jì)形勢和能源形勢的深刻變化,從傳統(tǒng)化石能源向清潔新能源過渡的新一輪能源變革已經(jīng)悄然展開。歐美等發(fā)達(dá)國家為了應(yīng)對氣候變化、促進(jìn)經(jīng)濟(jì)發(fā)展、調(diào)整能源結(jié)構(gòu)相繼提出發(fā)展智能電網(wǎng),我國也在政府工作報告中明確提出要“加強(qiáng)智能電網(wǎng)建設(shè)"。作為未來智能電網(wǎng)重要組成部分,固態(tài)變壓器(Solid State Transformer, SST)是一種利用電力電子器件和變換技術(shù)實現(xiàn)電壓等級轉(zhuǎn)換和電力傳輸?shù)男滦椭悄芑O(shè)備。與傳統(tǒng)變壓器相比,SST具有體積小、重量輕、環(huán)境友好以及故障隔離等特點,通過相關(guān)的控制技術(shù)可以對網(wǎng)側(cè)電壓電流和傳輸功率進(jìn)行調(diào)控；同時提供了交直流端口,可有效整合分布式新能源、儲能裝置以及各種交直流負(fù)載,進(jìn)而實現(xiàn)電網(wǎng)中功率潮流的協(xié)調(diào)分配,提高電網(wǎng)運(yùn)行的效率和可靠性。受到當(dāng)前電力電子器件水平的限制,固態(tài)變壓器一般通過模塊級聯(lián)的方式來提升裝置的容量和電壓等級。級聯(lián)的拓?fù)浣Y(jié)構(gòu)便于拓展、易封裝,但存在模塊之間的電壓和功率均衡控制問題。本文以應(yīng)用于配電網(wǎng)中級聯(lián)型固態(tài)變壓器為研究對象,對其應(yīng)用控制方法進(jìn)行了相關(guān)研究,提出一套基于“協(xié)同”思想的控制策略。首先,針對配電網(wǎng)中固態(tài)變壓器采用模塊級聯(lián)形式所帶來的模塊間電壓和功率均衡控制問題,通過分析輸入級和中間級的開關(guān)等效電路,推導(dǎo)得出級聯(lián)型固態(tài)變壓器的內(nèi)部功率傳輸模型,進(jìn)而得出電壓均衡和傳輸功率均衡的等價條件,在此基礎(chǔ)上提出了一種簡單、有效的前后級協(xié)同控制策略：輸入級采用單相DQ坐標(biāo)變換的共同占空比控制,中間級采用輸入輸出電壓疊加控制,二者協(xié)同配合實現(xiàn)串聯(lián)模塊的均壓和并聯(lián)模塊的均流控制。然后,針對分布式微源通過多端口固態(tài)變壓器交直流端口接入配電網(wǎng)后,固態(tài)變壓器對于微源、用戶和電網(wǎng)之間的功率協(xié)調(diào)管理問題,提出一種基于固態(tài)變壓器低壓直流端口電壓分區(qū)的功率協(xié)同控制策略。利用PSCAD/EMTDC軟件平臺建立了相應(yīng)的仿真模型,并且在實驗室搭建小功率試驗樣機(jī),最后仿真和實驗結(jié)果驗證了本文所提多端口級聯(lián)型固態(tài)變壓器功率協(xié)同控制策略的有效性和可行性。
[Abstract]:With the profound changes of economic and energy situation at home and abroad, a new round of energy transformation from traditional fossil energy to clean new energy has been launched quietly. In order to cope with climate change and promote economic development, developed countries such as Europe and the United States have put forward the development of smart grid one after another by adjusting energy structure. In our government work report, we have clearly proposed to "strengthen the construction of smart grid". As an important part of the future smart grid, solid state transformer solid State Transformer, SST) is a new type of intelligent equipment which uses power electronic devices and conversion technology to realize voltage grade conversion and power transmission. Compared with the traditional transformer, SST has the characteristics of small size, light weight, friendly environment and fault isolation. It can regulate the voltage, current and transmission power of the grid side by means of the related control technology, and also provides the AC / DC port. It can effectively integrate distributed new energy, energy storage devices and all kinds of AC / DC loads, and then realize the coordinated distribution of power flow in the power grid, and improve the efficiency and reliability of power grid operation. Due to the limitation of the current power electronic devices, solid-state transformers usually use modular cascading to enhance the capacity and voltage level of the devices. The topology of cascade is easy to expand and encapsulate, but there are voltage and power equalization control problems between modules. In this paper, the application of solid state transformer in distribution network is studied, and a set of control strategy based on the idea of "cooperation" is put forward. Firstly, aiming at the problem of voltage and power equalization control between modules brought by solid-state transformer in distribution network, the switching equivalent circuit of input stage and intermediate stage is analyzed. The internal power transmission model of cascaded solid-state transformer is derived, and the equivalent condition of voltage equalization and transmission power equalization is obtained. The effective control strategy is as follows: the input stage adopts the common duty cycle control of single-phase DQ coordinate transformation, the middle stage adopts the input and output voltage superposition control, the two cooperate to realize the voltage sharing of the series module and the current sharing control of the parallel module. Then, after the distributed microsource is connected to the distribution network through the multi-port solid-state transformer, the power coordination management between the microsource, the user and the power grid is discussed. A power cooperative control strategy based on low voltage DC port voltage partition of solid state transformer is proposed. The corresponding simulation model is established by using PSCAD/EMTDC software platform, and a small power test prototype is built in the laboratory. Finally, the simulation and experimental results show the effectiveness and feasibility of the multi-port cascaded solid-state transformer power cooperative control strategy proposed in this paper.
【學(xué)位授予單位】：湖南大學(xué)
【學(xué)位級別】：碩士
【學(xué)位授予年份】：2016
【分類號】：TM41
，

本文編號：1978557