本發明之主要目的係在於克服習知技藝所遭遇之上述問題，並提供一種考慮分散式發電之區域電網，實現兩個區域電網之間同步之新方法 ，可適用於兩個同時具諧波與不平衡電壓之區域電網同步併聯之電力系統區域間之同步併聯控制方法。 本發明之次要目的係在於提供一種透過考慮相電壓之公式，將同步控制器運用傅立葉轉換（Fourier Transform, FT）及派克轉換（Park Transform）結合鎖相迴路（Phase-locked Loop, PLL）進行區域電網與區域電網之間之同步併聯相位差計算，並結合於逆變器以減少兩個區域電網之相位差，經本發明運用實際區域電網模擬結果，證明本方法不需要複雜之控制法則或調整控制增益，即可達到快速及無縫同步等實用功效之電力系統區域間之同步併聯控制方法。 為達以上之目的，本發明係一種電力系統區域間之同步併聯控制方法 ，係於兩個區域電網中第一區域電網與第二區域電網具有相位差且有三相電壓不平衡及諧波分量同時存在之情況下，輸入該第一區域電網與該第二區域電網介面母線電壓至一同步控制器，該同步控制器位在該第一區域電網或該第二區域電網之中，由該同步控制器進行運算、轉換及比較後得到一相位差，並將該相位差迴授至所處區域電網之逆變器，以利用此相位差作為該第一區域電網與該第二區域電網同步併聯之調控參考，進而讓該同步控制器控制該逆變器進行同步，而使該逆變器可輸出無縫同步之電壓、頻率及相位； 其中一個區域電網含有該同步控制器，而該同步控制器係包含有一k
1及k
2計算單元、一與該k
1及k
2計算單元連接之傅立葉轉換計算單元、一與該k
1及k
2計算單元及該傅立葉轉換計算單元連接之相位差計算單元、一與該相位差計算單元連接之PI控制器、一與該PI控制器連接之鎖相迴路、以及一與該PI控制器連接之電壓/電流控制器，而該k
1及k
2計算單元係配合該第一區域電網與該第二區域電網各介面母線電壓進行所需之運算，再配合該PI控制器對運算結果進行轉換，當操作時，該第一區域電網介面母線電壓中A相電壓為
、B相電壓為
、C相電壓為
，而第二區域電網介面母線電壓中A相電壓為
、B相電壓為
、C相電壓為
，若
，而
，則可由該k
1及k
2計算單元配合該傅立葉轉換計算單元與該相位差計算單元經運算後獲得
；該PI控制器係將得到之
轉換 為
，並藉由該鎖相迴路得到該同步控制器所處區域之相位差
取得新相位差
後，作派克（Park，即abc轉dq）轉換，其中，該
為第一區域電網介面A相母線於h次諧波電壓幅值；該
為第二區域電網介面A相母線於h次諧波電壓幅值；H為考慮的總諧波次；以及P
1shh、P
1c hh、P
2shh與P
2c hh為四個計算出的常數。 於本發明上述實施例中，該傅立葉轉換計算單元係用以運算出區域電網交流端介面母線各次諧波電壓之幅值。 於本發明上述實施例中，該電壓/電流控制器係用以控制該逆變器，使該逆變器可輸出無縫同步之電壓、頻率及相位。
The main object of the present invention is to overcome the above problems encountered in the prior art, and to provide a new method for realizing synchronization between two regional power grids by considering a distributed power generation regional power grid, which can be applied to two simultaneous harmonics. Synchronous parallel control method between power system regions in which the regional power grids of the unbalanced voltage are synchronously connected in parallel. A secondary object of the present invention is to provide a synchronous controller using Fourier transform (FT) and Park Transform combined with a phase-locked loop (PLL) by considering a phase voltage formula. The synchronous parallel phase difference calculation between the regional power grid and the regional power grid is combined with the inverter to reduce the phase difference between the two regional power grids. The present invention uses the actual regional power grid simulation results to prove that the method does not require complicated control rules or adjustments. By controlling the gain, a synchronous parallel control method between power system regions that achieves practical effects such as fast and seamless synchronization can be achieved. For the purpose of the above, the present invention is a synchronous parallel control method between power system regions, in which the first regional power grid and the second regional power grid have phase difference and have three-phase voltage imbalance and harmonic components simultaneously in two regional power grids. If yes, the first regional power grid and the second regional power grid interface bus voltage are input to a synchronous controller, and the synchronous controller is located in the first regional power grid or the second regional power grid, and is controlled by the synchronization After calculating, converting and comparing, a phase difference is obtained, and the phase difference is fed back to the inverter of the regional power grid to utilize the phase difference as the first regional power grid and the second regional power grid are synchronously connected in parallel. Regulating the reference, and then letting the synchronous controller control the inverter to synchronize, so that the inverter can output seamlessly synchronized voltage, frequency and phase; wherein one regional grid contains the synchronous controller, and the synchronous controller system comprises a k 1 and k 2 calculation unit 2 calculates a Fourier transform unit connected to the computing unit to the k 1 and k, and a k 1 and k 2 of the computing unit and the FU a phase difference calculation unit connected to the stage conversion calculation unit, a PI controller connected to the phase difference calculation unit, a phase lock circuit connected to the PI controller, and a voltage/current controller connected to the PI controller And the k 1 and k 2 computing units perform the required operations on the bus voltages of the first regional power grid and the second regional power grid, and then cooperate with the PI controller to convert the operation result, when operating, The phase A voltage in the bus voltage of the first regional power grid interface is , phase B voltage is , phase C voltage is And the phase A voltage in the bus voltage of the second regional power grid interface is , phase B voltage is , phase C voltage is If ,and And the k 1 and k 2 calculation unit can be obtained by the operation of the Fourier transform calculation unit and the phase difference calculation unit. ; the PI controller will get it Convert to And obtaining the phase difference of the region where the synchronous controller is located by using the phase locked loop Get a new phase difference After that, Park (Park, ie abc to dq) conversion, where The magnitude of the hth harmonic voltage of the A-phase bus of the first regional power grid interface; For the second regional grid interface A phase bus is at the hth harmonic voltage amplitude; H is the total harmonic order considered; and P 1shh , P 1c hh , P 2shh and P 2c hh are the four calculated constants. In the above embodiment of the present invention, the Fourier transform calculation unit is configured to calculate the amplitude of each harmonic voltage of the bus bar of the regional power exchange interface. In the above embodiment of the present invention, the voltage/current controller is used to control the inverter so that the inverter can output seamlessly synchronized voltage, frequency and phase.
電力系統區域與區域間之公共耦合點必須符合相關標準。當區域電網要進行併聯時，不同的兩個區域電網不論電壓幅值、相角都不盡相同，此時區域電網是一個電壓不平衡與失真的系統。對此，本發明提出適用於兩個同時具諧波與不平衡電壓之區域電網同步併聯控制技術。請參閱『第１圖～第５圖』所示，係分別為本發明之方塊流程示意圖、本發明以情境一比較無同步下在t=0.7秒併聯示意圖、本發明以情境一模擬考慮
而在t=0.7475秒達到無縫併聯示意圖、本發明以情境二模擬考慮
而在t=0.7503秒達到無縫併聯示意圖、及本發明以情境二所得
之變化示意圖。如圖所示：本發明係一種電力系統區域間之同步併聯控制方法，係於兩個區域電網之第一區域電網１與第二區域電網２具有相位差且有三相電壓不平衡及諧波分量同時存在之情況下，輸入該第一區域電網１與該第二區域電網２介面母線電壓至一同步控制器３，該同步控制器３可位在該第一區域電網１或該第二區域電網２任一者中，由該同步控制器３進行運算、轉換及比較後得到一相位差，並將該相位差迴授至所處區域電網之逆變器４，以利用此相位差作為該第一區域電網１與該第二區域電網２同步併聯之調控參考，進而讓該同步控制器３控制該逆變器４進行同步，而使該逆變器４可輸出無縫同步之電壓、頻率及相位。 由第１圖觀之，該兩個區域電網１、２係與該同步控制器３連接，而該同步控制器３係包含有一k
1及k
2計算單元３１、一與該k
1及k
2計算單元３１連接之傅立葉轉換計算單元３２、一與該k
1及k
2計算單元３１及該傅立葉轉換計算單元３２連接之相位差計算單元３３、一與該相位差計算單元３３連接之PI控制器３４、一與該PI控制器３４連接之鎖相迴路３５、以及一與該PI控制器３４連接之電壓/電流控制器３６，而該k
1及k
2計算單元３１係配合該第一區域電網１與該第二區域電網２各介面母線電壓進行所需之運算，再配合該PI控制器３４對運算結果進行轉換。 當操作時，假設在兩個區域電網中，即第一區域電網１與第二區域電網２，該兩區域電網１、２有相位差
且有負載不平衡及諧波分量同時存在時，本發明係提出一關係式，可藉由此關係式改善區域電網交流端之相位差。以下為關係式推導： 第一區域電網１介面母線電壓如下： A相電壓為
； B相電壓為
； C相電壓為
。 第二區域電網２介面母線電壓如下： A相電壓為
； B相電壓為
； C相電壓為
。 其中，該
為第一區域電網１介面A相母線於h次諧波電壓幅值；以及該
為第二區域電網２介面A相母線於h次諧波電壓幅值。 令：
；
，則可由該k
1及k
2計算單元３１配合該傅立葉轉換計算單元３２與該相位差計算單元３３運算。若對第一區域電網１及第二區域電網２只取二次諧波項計算，則：
；
；
；
； 令上述兩式中，
之
係數以符號
、
之係數以符號
表示之；以及
之
係數以符號
、
之係數以符號
表示之，則
及
可簡寫成：
；
， 將上式整理後可得到
之關係式：
； 對於通案，考慮第一區域電網１及第二區域電網２，各取1、2、…、H次諧波項計算，則
之關係式為：
； 即
。 如是，本發明利用此
之關係式實現同步控制器３之架構如第１圖所示，並利用第１圖中所建立之區域電網１、２架構，進行區域電網１、２間之同步併聯。假設所提出之同步控制器３在第二區域電網２中，便可由該傅立葉轉換計算單元３２運算出第二區域電網２介面母線電壓之峰值，且由該相位差計算單元３３運算出
，之後再由該PI控制器３４係將得到之
轉換為
，並配合藉由該鎖相迴路３５得到該第二區域電網２之相位差
。當取得新相位差
後，作派克轉換（abc轉dq），利用d軸與q軸電壓執行電壓/電流控制器３６以控制逆變器４，使逆變器４可輸出無縫同步之電壓、頻率及相位以減少兩區域電網１、２之相位差來達到參考端區域電網與追蹤端區域電網之相位角同步。 下列為本發明之模擬比較結果： 本發明之同步併聯控制方法使用第１圖之區域電網系統做研究分析，第一區域電網１有微渦輪發電機１１（電壓/頻率模式，45kW）、兩組太陽光伏陣列１２（定實功/虛功模式，60kW）、及兩組風力發電機１３（定實功/虛功模式，25kW）及五組負載組成，其中微渦輪發電機１１為電壓與頻率參考。第二區域電網２有太陽光伏陣列２１（定實功/虛功模式，60kW）與儲能系統２２（電壓/頻率模式，45kWh）及兩組負載組成，其中逆變器４具有本發明之同步控制器３。第一區域電網１透過靜態開關（Static Switch, SS）５連接第二區域電網２。區域電網額定負載電壓為380V。 情境一：兩區域電網１、２之電壓大小與頻率皆相同，相位差
為120°。如第２圖所示，靜態開關在t=0.7秒時閉合，此時因無同步，所以發生巨大暫態。如第３圖所示，在相同情況下，應用本發明之方法模擬，0.5秒時開始進行同步併聯動作，接近t=0.7475秒時，藉由第１圖同步控制器３兩區域電網１、２可無縫併聯。 情境二：兩區域電網１、２之負載不平衡且有諧波存在，第一區域電網１之五組三相負載為40kW+3.02kVAr、20kW+1.01kVAr、30kW+2.01kVAr，第二區域電網２之兩組三相負載為30kW+3.02kVAr 、20kW+1.01kVAr、40kW+2.01kVAr，低通濾波器參數為L=1100μH、C=2300μF其截止頻率為100Hz，總諧波失真率（Total Harmonic Distortion）為5.62%，相位角
為120°。如第４圖與第５圖所示，本發明之同步控制器３在t=0.5秒時開始進行同步併聯動作，接近t=0.7503藉由
使兩區域電網１、２可無縫併聯及相位角趨近於零。 藉此，本發明係考慮分散式發電之區域電網，實現兩個區域電網之間同步之新方法，可適用於兩個同時具諧波與不平衡電壓之區域電網同步併聯。由相位差且有三相電壓不平衡與諧波電壓引起之實際相位差 ，在本發明中充分被考慮進來。透過考慮相電壓之公式，同步控制器運用傅立葉轉換及派克轉換結合鎖相迴路進行區域電網與區域電網之間之同步併聯相位差計算，並結合於逆變器以減少兩區域電網之相位差，而經本發明運用實際區域電網模擬結果，足以驗證本方法不需要複雜之控制法則或調整控制增益，即可達到快速及無縫同步之實用功效。 綜上所述，本發明係一種電力系統區域間之同步併聯控制方法，可有效改善習用之種種缺點，透過考慮相電壓之公式，可適用於兩個同時具諧波與不平衡電壓之區域電網同步併聯，無需複雜之控制法則或調整控制增益，即可達到快速及無縫同步之實用功效，進而使本發明之産生能更進步、更實用、更符合使用者之所需，確已符合發明專利申請之要件，爰依法提出專利申請。 惟以上所述者，僅為本發明之較佳實施例而已，當不能以此限定本發明實施之範圍；故，凡依本發明申請專利範圍及發明說明書內容所作之簡單的等效變化與修飾，皆應仍屬本發明專利涵蓋之範圍內。
The point of common coupling between the area of the power system and the area must comply with relevant standards. When the regional power grids are to be connected in parallel, the voltages and phase angles of the two different regional power grids are different. At this time, the regional power grid is a system of voltage imbalance and distortion. In this regard, the present invention proposes a synchronous parallel control technique for two regional power grids with both harmonic and unbalanced voltages. Please refer to FIG. 1 to FIG. 5 respectively, which are schematic diagrams of the block flow of the present invention, and the present invention is a parallel schematic diagram of t=0.7 seconds in the context of a situation without synchronization, and the present invention takes context-simulation into consideration. And the seamless parallel diagram is achieved at t=0.7475 seconds, and the present invention is considered in the context of the second simulation. And the seamless parallel schematic diagram is obtained at t=0.7503 seconds, and the invention is obtained by the situation 2 A schematic diagram of the changes. As shown in the figure: the present invention is a synchronous parallel control method between power system regions, which is that the first regional power grid 1 and the second regional power grid 2 of the two regional power grids have a phase difference and have three-phase voltage imbalance and harmonic components. In the case of the same, the first regional power grid 1 and the second regional power grid 2 interface bus voltage are input to a synchronous controller 3, and the synchronous controller 3 can be located in the first regional power grid 1 or the second regional power grid. In any of the two, the synchronization controller 3 performs calculation, conversion, and comparison to obtain a phase difference, and returns the phase difference to the inverter 4 of the regional power grid to utilize the phase difference as the first a regional power grid 1 and the second regional power grid 2 synchronously parallel control reference, and then the synchronous controller 3 controls the inverter 4 to synchronize, so that the inverter 4 can output seamless synchronous voltage, frequency and Phase. As shown in FIG. 1, the two regional power grids 1, 2 are connected to the synchronous controller 3, and the synchronous controller 3 includes a k 1 and k 2 computing unit 31, and the k 1 and k 2 A Fourier transform calculation unit 32 connected to the calculation unit 31, a phase difference calculation unit 33 connected to the k 1 and k 2 calculation unit 31 and the Fourier transform calculation unit 32, and a PI controller connected to the phase difference calculation unit 33 34. A phase-locked loop 35 connected to the PI controller 34, and a voltage/current controller 36 connected to the PI controller 34, and the k 1 and k 2 computing unit 31 cooperate with the first regional power grid 1 Perform the required calculation with the bus voltage of each interface of the second regional power grid 2, and then cooperate with the PI controller 34 to convert the operation result. When operating, it is assumed that in the two regional grids, namely the first regional grid 1 and the second regional grid 2, the two regional grids 1, 2 have a phase difference When there is load imbalance and harmonic components coexist, the present invention proposes a relationship by which the phase difference of the AC end of the regional power grid can be improved. The following is the relationship derivation: The first regional grid 1 interface bus voltage is as follows: Phase A voltage is ; Phase B voltage is ; Phase C voltage is . The voltage of the second regional grid 2 interface bus is as follows: Phase A voltage is ; Phase B voltage is ; Phase C voltage is . Among them, the The magnitude of the hth harmonic voltage of the A-phase bus of the first regional grid 1 interface; and For the second regional grid 2 interface A phase bus is at the hth harmonic voltage amplitude. make: ; The k 1 and k 2 calculation unit 31 can be operated by the Fourier transform calculation unit 32 and the phase difference calculation unit 33. If the second harmonic term is calculated for the first regional power grid 1 and the second regional power grid 2, then: ; ; ; In the above two formulas, It Coefficient with symbol , Coefficient with symbol Expressed; and It Coefficient with symbol , Coefficient with symbol Indicating it, then and Can be abbreviated as: ; , after finishing the above formula, you can get Relationship: For the general case, consider the first regional grid 1 and the second regional grid 2, each taking 1, 2, ..., H harmonic calculations, then The relationship is: ; which is . If so, the present invention utilizes this The relationship between the synchronous controller 3 and the architecture of the synchronous controller 3 is as shown in Fig. 1, and the regional grids 1 and 2 are constructed in parallel, and the parallel connection between the regional grids 1 and 2 is performed. Assuming that the proposed synchronous controller 3 is in the second regional power grid 2, the peak value of the second regional grid 2 interface bus voltage can be calculated by the Fourier transform calculation unit 32, and is calculated by the phase difference calculating unit 33. And then the PI controller 34 will get it. Convert to And matching the phase difference of the second regional power grid 2 by the phase locked loop 35 . When a new phase difference is obtained After that, a Parker conversion (abc to dq) is performed, and the voltage/current controller 36 is executed by the d-axis and q-axis voltages to control the inverter 4, so that the inverter 4 can output seamlessly synchronized voltages, frequencies, and phases to reduce The phase difference between the two regional power grids 1 and 2 is to achieve phase angle synchronization between the reference end regional power grid and the tracking end regional power grid. The following is the simulation comparison result of the present invention: The synchronous parallel control method of the present invention uses the regional power grid system of Fig. 1 for research and analysis, and the first regional power grid 1 has a micro-turbine generator 11 (voltage/frequency mode, 45 kW), two groups. Solar photovoltaic array 12 (fixed power / virtual power mode, 60kW), and two sets of wind turbines 13 (fixed power / virtual work mode, 25kW) and five sets of loads, of which micro-turbine generator 11 is voltage and frequency reference. The second regional power grid 2 has a solar photovoltaic array 21 (fixed power/virtual power mode, 60 kW) and an energy storage system 22 (voltage/frequency mode, 45 kWh) and two sets of loads, wherein the inverter 4 has the synchronization of the present invention. Controller 3. The first regional power grid 1 is connected to the second regional power grid 2 via a static switch (SS) 5. The regional grid rated load voltage is 380V. Situation 1: The voltage and frequency of the two regional grids 1 and 2 are the same, the phase difference It is 120°. As shown in Fig. 2, the static switch is closed at t = 0.7 seconds, and at this time, there is no synchronization, so a huge transient occurs. As shown in Fig. 3, in the same case, the method of the present invention is applied to simulate, and the synchronous parallel operation starts at 0.5 seconds, and when t=0.7475 seconds, the two-area grid 1 and 2 are synchronized by the first figure. Can be connected in parallel. Scenario 2: The load of the two regional power grids 1 and 2 is unbalanced and there are harmonics. The five-phase three-phase load of the first regional power grid 1 is 40kW+3.02kVAr, 20kW+1.01kVAr, 30kW+2.01kVAr, the second regional power grid. The two sets of three-phase loads are 30kW+3.02kVAr, 20kW+1.01kVAr, 40kW+2.01kVAr, the low-pass filter parameters are L=1100μH, C=2300μF, the cutoff frequency is 100Hz, and the total harmonic distortion rate (Total Harmonic) Distortion) is 5.62%, phase angle It is 120°. As shown in FIGS. 4 and 5, the synchronous controller 3 of the present invention starts the synchronous parallel operation at t=0.5 seconds, which is close to t=0.7503 by The two regional grids 1, 2 can be seamlessly connected and the phase angle approaches zero. Therefore, the present invention considers a regional power grid for distributed power generation, and realizes a new method for synchronizing between two regional power grids, which can be applied to synchronous parallel connection of two regional power grids with both harmonic and unbalanced voltages. The actual phase difference caused by the phase difference and the three-phase voltage imbalance and the harmonic voltage is sufficiently considered in the present invention. By considering the phase voltage formula, the synchronous controller uses Fourier transform and Parker conversion combined with the phase-locked loop to calculate the synchronous parallel phase difference between the regional power grid and the regional power grid, and combines with the inverter to reduce the phase difference between the two regional power grids. The actual regional power grid simulation result of the present invention is sufficient to verify that the method does not require complicated control rules or adjusts the control gain, thereby achieving the practical effect of fast and seamless synchronization. In summary, the present invention is a synchronous parallel control method between power system regions, which can effectively improve various shortcomings of the conventional use, and can be applied to two regional power grids with both harmonic and unbalanced voltages by considering the phase voltage formula. Synchronous parallel connection, without complicated control rules or adjustment control gain, can achieve the practical effect of fast and seamless synchronization, so that the invention can be more advanced, more practical, and more in line with the needs of users. For the requirements of the patent application, the patent application is filed according to law. However, the above is only the preferred embodiment of the present invention, and the scope of the present invention is not limited thereto; therefore, the simple equivalent changes and modifications made in accordance with the scope of the present invention and the contents of the invention are modified. All should remain within the scope of the invention patent.