JPH0599969A - Three phase electronlike loading device - Google Patents
Three phase electronlike loading deviceInfo
- Publication number
- JPH0599969A JPH0599969A JP3264341A JP26434191A JPH0599969A JP H0599969 A JPH0599969 A JP H0599969A JP 3264341 A JP3264341 A JP 3264341A JP 26434191 A JP26434191 A JP 26434191A JP H0599969 A JPH0599969 A JP H0599969A
- Authority
- JP
- Japan
- Prior art keywords
- load
- voltage
- power
- value
- converter
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
Abstract
Description
【０００１】[0001]
【産業上の利用分野】この発明は、交流電源に接続され
て各種の負荷（抵抗負荷，誘導性負荷，容量性負荷，電
力など）を模擬するための電子的負荷装置、特に電圧の
変動に対する電力変動量を模擬可能にした電子的負荷装
置に関する。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electronic load device connected to an AC power source for simulating various loads (resistive load, inductive load, capacitive load, electric power, etc.), and particularly to voltage fluctuation. The present invention relates to an electronic load device capable of simulating the amount of power fluctuation.
【０００２】[0002]
【従来の技術】図４にこの種の従来例を示す。すなわ
ち、電子的負荷装置（以下、単に負荷装置ともいう）１
は交流電源装置２Ａの両端に接続されたＡ／Ｄコンバー
タ１１と、その出力側に接続されたマイクロコンピュー
タの如きディジタル演算装置（以下、マイコンともいい
ＭＰとも略記する）１２と、その出力側に接続されたＤ
／Ａコンバータ１３と、その出力側に接続されかつ交流
電源装置２Ａの両端に接続された電流源１４とから構成
される。ここで、例えば負荷特性として定電力の場合の
例につき説明する。いま、負荷特性設定値としての設定
消費電力値をＭ（ベクトル量）とすると、負荷装置１の
入力インピーダンスＺ（ベクトル量）は、 Ｚ＝Ｖｒ2 ／Ｍ …（ａ） となる。なお、Ｖｒは入力電圧Ｖ（ベクトル量）の実効
値を示す。2. Description of the Related Art FIG. 4 shows a conventional example of this kind. That is, an electronic load device (hereinafter, also simply referred to as a load device) 1
Is an A / D converter 11 connected to both ends of the AC power supply device 2A, a digital operation device (hereinafter also referred to as a microcomputer or MP) 12 such as a microcomputer connected to the output side thereof, and an output side thereof. Connected D
The / A converter 13 and a current source 14 connected to the output side of the A / A converter 13 and to both ends of the AC power supply device 2A. Here, an example of a case where the load characteristic is constant power will be described. Now, assuming that the set power consumption value as the load characteristic set value is M (vector amount), the input impedance Z (vector amount) of the load device 1 is Z = Vr 2 / M (a). Note that Vr represents the effective value of the input voltage V (vector amount).
【０００３】一方、負荷電流Ｉ（ベクトル量）は、 Ｉ＝Ｖ／Ｚ＝（Ｍ／Ｖｒ2 ）Ｖ …（ｂ） となる。ここに、入力電圧Ｖおよび負荷電流Ｉを図５
（イ），（ロ）の如くサンプリングして得るものとする
と、負荷電流Ｉｉは、 Ｉｉ＝（Ｍ／Ｖｒ2 ）Ｖｉ …（ｃ） と表わされる。そこで、各サンプリング周期毎にマイコ
ン１２にて実効値Ｖｒを求めて上記（ｃ）式の演算を行
ない、その結果得られるＩｉを負荷電流設定値として出
力すれば、負荷装置１は常に一定の電力Ｍを消費するこ
ととなる。なお、実効値Ｖは図５（イ）の如く入力電圧
Ｖｉの１周期内でｎ回サンプリングしたと仮定し、各サ
ンプリング時刻の電圧の瞬時値をＶ（１），Ｖ（２），
Ｖ（ｉ）…Ｖ（ｎ）とすると、次の数２により求めるこ
とができる。また、実効値Ｖｒは各サンプリング周期が
経過する毎に、それ以前のｎ回のサンプリングデータを
用いて求められる。On the other hand, the load current I (vector amount) is I = V / Z = (M / Vr 2 ) V (b). Here, the input voltage V and the load current I are shown in FIG.
If it is obtained by sampling as in (a) and (b), the load current Ii is expressed as Ii = (M / Vr 2 ) Vi (c). Therefore, if the effective value Vr is calculated by the microcomputer 12 for each sampling cycle and the above equation (c) is calculated and the resulting Ii is output as the load current setting value, the load device 1 will always have a constant power. M will be consumed. It is assumed that the effective value V is sampled n times within one cycle of the input voltage Vi as shown in FIG. 5A, and the instantaneous value of the voltage at each sampling time is V (1), V (2),
If V (i) ... V (n), then it can be calculated by the following equation 2. Further, the effective value Vr is obtained every time each sampling period elapses, using the sampling data n times before that.
【数２】 [Equation 2]
【０００４】以上は定電力の場合であるが、一般的な電
力負荷を模擬する場合は、その負荷特性として、 Ｐ＝Ｐ0 ＊（Ｖ／Ｖ0 ）a ＊｛（１＋ｓＴ1 ）／（１＋ｓＴ2 ）｝…（ｄ） （Ｐは負荷のとる電力、Ｐ0 はその初期値、Ｖは系統負
荷端実効電圧、Ｖ0 はその初期値、ａは例えば０〜２の
範囲の可変値、ｓはラプラス演算子、Ｔ1 ，Ｔ2 は時定
数をそれぞれ示す。）なる負荷モデルを用いる方法が知
られている。The above is the case of constant power, but when simulating a general power load, the load characteristics are: P = P 0 * (V / V 0 ) a * {(1 + sT 1 ) / (1 + sT 2 )} ... (d) (P is the power taken by the load, P 0 is its initial value, V is the system load end effective voltage, V 0 is its initial value, a is, for example, a variable value in the range of 0 to 2, s Is a Laplace operator, and T 1 and T 2 are time constants.) Is known.
【０００５】[0005]
【発明が解決しようとする課題】しかしながら、上記
（ｄ）式を用いるものは電圧の過渡的な陥没変動（ステ
ップ変動）に対して、電力の陥没変動量が陽に表現され
ず全て時定数により陰に表現されるため、現実に則した
模擬が出来ないという問題がある。したがって、この発
明の課題はより現実に近い模擬が可能な３相電子的負荷
装置を提供することにある。However, in the case of using the above equation (d), the amount of power depression change is not explicitly expressed with respect to the transient depression fluctuation (step fluctuation) of the voltage, and all of them depend on the time constant. Since it is expressed in the shadow, there is a problem that it is not possible to simulate in reality. Therefore, an object of the present invention is to provide a three-phase electronic load device capable of more realistic simulation.
【０００６】[0006]
【課題を解決するための手段】かかる課題を解決するた
め、この発明では、電源装置からの入力電圧のサンプリ
ング値をディジタル信号に変換するＡ／Ｄコンバータ
と、このディジタル信号および負荷特性設定値に応じた
負荷電流設定値を演算するディジタル演算装置と、この
負荷電流設定値をアナログ信号に変換するＤ／Ａコンバ
ータと、前記電源装置に接続され前記アナログ信号にも
とづいて負荷電流を発生する電流源とを、前記電源装置
を３相としてそれぞれ３系統有してなる３相電子的負荷
装置において、前記負荷特性設定値として上記数１で示
される如き電力系統において取得される負荷動特性モデ
ルを用い、電圧の変動に対する電力変動量を模擬可能に
したことを特徴としている。In order to solve such a problem, according to the present invention, an A / D converter for converting a sampling value of an input voltage from a power supply device into a digital signal, and a digital signal and a load characteristic set value are provided. A digital arithmetic unit for calculating a load current setting value according to the digital signal, a D / A converter for converting the load current setting value into an analog signal, and a current source connected to the power supply unit for generating a load current based on the analog signal. And a load dynamic characteristic model acquired in a power system as shown in the above mathematical expression 1 as the load characteristic set value in a three-phase electronic load device having three systems each of which has the power supply device as three phases. The feature is that it is possible to simulate the amount of power fluctuation with respect to voltage fluctuation.
【０００７】[0007]
【作用】負荷特性設定値として、実際の電力系統に適用
して実績のある動特性モデルを用いることにより、電圧
の過渡的変動に対応する電力の過渡的変動量をより忠実
に模擬し得るようにする。[Function] As the load characteristic set value, by using a dynamic characteristic model that has been applied to an actual power system and has a proven track record, it is possible to more faithfully simulate the transient fluctuation amount of power corresponding to the transient fluctuation of voltage. To
【０００８】[0008]
【実施例】図１はこの発明の実施例を示す構成図であ
る。同図において、１Ａ，１Ｂ，１ＣはそれぞれＡ／Ｄ
コンバータ１１Ａ，１１Ｂ，１１Ｃ、マイコン１２Ａ，
１２Ｂ，１２Ｃ，Ｄ／Ａコンバータ１３Ａ，１３Ｂ，１
３Ｃおよび電圧／電流変換器１４Ａ，１４Ｂ，１４Ｃか
らなる電子的負荷装置、２は３相電源装置で、同図から
も明らかなように、この実施例は図４に示す従来例を３
相対応としたことにある。なお、図１の電圧／電流変換
器１４Ａ，１４Ｂ，１４Ｃは図４の電流源１４に相当す
る。したがって、この例においても負荷特性として電力
系統用の動特性モデルを与えることにより、その模擬が
可能となる。そこで、この発明では実際の電力系統にお
いて取得された、数３の如き負荷動特性モデルを用い
る。なお、この動特性モデルは各種の電力負荷に適用し
て良好な結果を得ているもので、例えば昭和６３年電気
学会全国大会にて発表の論文集第９４２（負荷動特性モ
デルのパラメータ合成方法），第９４３（系統負荷特性
の解析用ソフトウエアの開発）および第９８２（系統負
荷特性の実測）等により公知のものである。なお、数３
のΔｔは演算周期を示す。また、Ａｐは電圧過渡変動に
対する電力の過渡変動量相当の設定パラメータ、Ｔｐは
時定数設定パラメータ、ｎp は静的な電圧特性係数設定
パラメータを示し、これらのパラメータは負荷特性に応
じて適宜設定される定数とする。1 is a block diagram showing an embodiment of the present invention. In the figure, 1A, 1B, and 1C are A / Ds, respectively.
Converter 11A, 11B, 11C, microcomputer 12A,
12B, 12C, D / A converters 13A, 13B, 1
3C and voltage / current converters 14A, 14B, 14C, an electronic load device, 2 is a three-phase power supply device, and as is clear from the figure, this embodiment is the conventional example shown in FIG.
There is a correspondence. The voltage / current converters 14A, 14B and 14C in FIG. 1 correspond to the current source 14 in FIG. Therefore, also in this example, by providing the dynamic characteristic model for the electric power system as the load characteristic, the simulation can be performed. Therefore, in the present invention, a load dynamic characteristic model such as Equation 3 acquired in an actual power system is used. It should be noted that this dynamic characteristic model has been applied to various electric loads and has obtained good results. ), 943 (development of software for analysis of system load characteristics) and 982 (measurement of system load characteristics) and the like. The number 3
Δt indicates the calculation cycle. Further, Ap is a setting parameter corresponding to the amount of transient fluctuation of electric power with respect to voltage transient fluctuation, Tp is a time constant setting parameter, np is a static voltage characteristic coefficient setting parameter, and these parameters are appropriately set according to load characteristics. Is a constant.
【数３】 [Equation 3]
【０００９】しかし、上記数３は級数和の形式をとって
いるため、メモリ容量が多大となりオンライン処理に適
さないという難点がある。そこで、この発明ではオンラ
インで処理可能とするため、数３の右辺級数和の部分Δ
Ｐｉを次の数４にて示すような差分形式を用い、数５の
如く表現される式として取り扱うようにしている。However, since the above equation 3 is in the form of series sum, it has a drawback that the memory capacity becomes large and it is not suitable for online processing. Therefore, in the present invention, since processing can be performed online, the part Δ of the right-side series sum of Equation 3 is
Pi is treated as an expression expressed by Expression 5 by using a differential format shown by Expression 4 below.
【数４】 [Equation 4]
【数５】 [Equation 5]
【００１０】電圧の変動をステップ状の変化と仮定すれ
ば、 ΔＰ（ｉ）≒Ｐ0 ＊Δｙ（ｉ）＊Ｖ0 ＊｛Ｖ（ｉ）／Ｖ0 ｝np+1 の如く、級数和が差分式で表現できることについて以下
に説明する。図２は数４に対応する差分方程式を導出す
るためのブロック図、図３は数５を実現するブロック図
である。すなわち、図２のブロック図で示される伝達関
数をＺ変換すると数６となり、この数６から数７が得ら
れる。Assuming that the voltage change is a step change, the sum of series is expressed as ΔP (i) ≈P 0 * Δy (i) * V 0 * {V (i) / V 0 } np + 1. What can be expressed by a difference formula will be described below. 2 is a block diagram for deriving a difference equation corresponding to equation 4, and FIG. 3 is a block diagram for realizing equation 5. That is, when the transfer function shown in the block diagram of FIG. 2 is Z-transformed, Equation 6 is obtained, and Equation 6 to Equation 7 are obtained.
【数６】 [Equation 6]
【数７】 [Equation 7]
【００１１】ここで、ｘ（ｉ）＝１／Ｖ（ｉ）とおき、
ｙ（０）からの和として数７を表現すれば、数８とな
る。また、Δｙ（０）でステップ状の電圧変化を仮定
し、 Ｖ（０）≠Ｖ（１）＝Ｖ（２）…＝Ｖ（ｉ） ならば、数９のようにΔＰ（ｉ）が求まり、そのブロッ
ク図は図３のように表わされる。Where x (i) = 1 / V (i),
If Equation 7 is expressed as the sum from y (0), Equation 8 is obtained. Further, assuming a stepwise voltage change with Δy (0), and if V (0) ≠ V (1) = V (2) ... = V (i), then ΔP (i) can be obtained as in Equation 9. The block diagram is shown in FIG.
【数８】 [Equation 8]
【数９】 このようにして、上記数３は数４の如き差分方程式で表
わされるので、図１のＭＰ１２Ａ，１２Ｂ，１２Ｃでは
これを用いて、以下のように電流指令等を演算する。ま
ず、サンプリングされＡ／Ｄコンバータ１１Ａ，１１
Ｂ，１１Ｃによりディジタル量に変換された瞬時電圧か
ら、先の数２を用いて各相の電圧実効値Ｖａ，Ｖｂ，Ｖ
ｃを求める。次に、上記数５より各相の電圧瞬時値Ｖａ
（ｉ），Ｖｂ（ｉ），Ｖｃ（ｉ）を用いて、電力指令値
を各相毎に演算する。次いで、下記（ｅ）式より、Ｖ
（ｉ）を電圧実効値としてアドミッタンスＧ（ｉ）を求
める。 Ｇ（ｉ）＝Ｐ（ｉ）／Ｖ（ｉ）2 …（ｅ） アドミッタンスＧ（ｉ）が求まれば電流指令値ｉ（ｉ）
は、次の（ｆ）式で与えられる。 ｉ（ｉ）＝Ｇ（ｉ）＊ｖ（ｉ） …（ｆ） （ただし、ｉ（ｉ）は演算周期毎の指示電流、ｖ（ｉ）
は演算周期毎の瞬時負荷電圧をそれぞれ示す。）[Equation 9] In this way, the above equation 3 is expressed by the difference equation such as the equation 4, so that the MP12A, 12B, and 12C of FIG. 1 use this to calculate the current command and the like as follows. First, sampled A / D converters 11A, 11
From the instantaneous voltage converted into a digital value by B and 11C, the voltage effective values Va, Vb and V of each phase are calculated by using the above equation 2.
Find c. Next, from the above equation 5, the instantaneous voltage value Va of each phase is calculated.
A power command value is calculated for each phase using (i), Vb (i), and Vc (i). Then, from the following equation (e), V
The admittance G (i) is obtained with (i) as the effective voltage value. G (i) = P (i) / V (i) 2 (e) If the admittance G (i) is obtained, the current command value i (i)
Is given by the following equation (f). i (i) = G (i) * v (i) (f) (where i (i) is the instruction current for each calculation cycle, v (i)
Indicates the instantaneous load voltage for each calculation cycle. )
【００１２】なお、以上では主として有効電力の場合に
ついて説明したが、無効電力の場合は位相を考慮して電
圧瞬時値の取り方を工夫することにより、上記と同様に
して模擬することができ、その式は先の数３のＰをＱに
置き換えて次の数１０のようになる。ここに、Ｑ（ｉ）
は負荷のとる無効電力、Ｑ0 はそれぞれの初期値、Ｖ
（ｉ）は時刻ｉでの系統電圧実効値、Ｖ0 はその初期
値、Ｖk ，Ｖk-1 はそれぞれ時刻ｋ，ｋ−１での系統電
圧実効値、ｎq は静的な電圧特性係数設定パラメータ、
Ａｑは電圧過渡変動に対する電力の過渡変動相当量の設
定パラメータ、Ｔｑは時定数設定パラメータ、Ｋ0 は定
数、ｅは指数関数、Δｔは演算周期をそれぞれ示してい
る。In the above, the case of active power was mainly explained, but in the case of reactive power, it can be simulated in the same manner as above by devising the method of taking the instantaneous voltage value in consideration of the phase, The formula becomes as shown in the following formula 10 by replacing P in the above formula 3 with Q. Where Q (i)
Is the reactive power taken by the load, Q 0 is the initial value of each, V
(I) is the effective value of the system voltage at time i, V 0 is its initial value, V k and V k-1 are the effective values of the system voltage at times k and k-1, respectively, and n q is the static voltage characteristic. Coefficient setting parameter,
Aq is a setting parameter of the amount of transient fluctuation of power with respect to voltage transient fluctuation, Tq is a time constant setting parameter, K 0 is a constant, e is an exponential function, and Δt is a calculation cycle.
【数１０】 [Equation 10]
【００１３】[0013]
【発明の効果】この発明によれば、電子的負荷装置の負
荷特性設定値として、実際の電力系統にて取得される負
荷動特性モデルを用いるようにしたので、電圧の変動に
対する電力変動量を忠実に模擬することができる利点が
得られる。According to the present invention, since the load dynamic characteristic model acquired in the actual power system is used as the load characteristic set value of the electronic load device, the power variation amount with respect to the voltage variation can be calculated. The advantage is that it can be faithfully simulated.
【図１】この発明の実施例を示す構成図である。FIG. 1 is a configuration diagram showing an embodiment of the present invention.
【図２】数４に対応する差分方程式を導出するためのブ
ロック図である。FIG. 2 is a block diagram for deriving a difference equation corresponding to Expression 4.
【図３】数５を実現するブロック図である。FIG. 3 is a block diagram for realizing Expression 5.
【図４】電子的負荷装置の従来例を示す構成図である。FIG. 4 is a configuration diagram showing a conventional example of an electronic load device.
【図５】入力電圧，負荷電流の各サンプリング例を説明
するための説明図である。FIG. 5 is an explanatory diagram for explaining each sampling example of an input voltage and a load current.
１ 電子的負荷装置 ２ ３相電源装置 ２Ａ 電源 １１，１１Ａ，１１Ｂ，１１Ｃ Ａ／Ｄコンバータ １２，１２Ａ，１２Ｂ，１２Ｃ ディジタル演算装置
（ＭＰ） １３，１３Ａ，１３Ｂ，１３Ｃ Ｄ／Ａコンバータ １４ 電流源 １４Ａ，１４Ｂ，１４Ｃ 電圧／電流（Ｖ／Ｉ）変換器1 Electronic load device 2 3 phase power supply device 2A power supply 11, 11A, 11B, 11C A / D converter 12, 12A, 12B, 12C Digital arithmetic unit (MP) 13, 13A, 13B, 13C D / A converter 14 Current source 14A, 14B, 14C voltage / current (V / I) converter
───────────────────────────────────────────────────── フロントページの続き (72)発明者 中西 要祐 神奈川県川崎市川崎区田辺新田１番１号 富士電機株式会社内 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Kaname Nakanishi 1-1 Tanabe Nitta, Kawasaki-ku, Kawasaki-shi, Kanagawa Fuji Electric Co., Ltd.
Claims (1)
値をディジタル信号に変換するＡ／Ｄコンバータと、こ
のディジタル信号および負荷特性設定値に応じた負荷電
流設定値を演算するディジタル演算装置と、この負荷電
流設定値をアナログ信号に変換するＤ／Ａコンバータ
と、前記電源装置に接続され前記アナログ信号にもとづ
いて負荷電流を発生する電流源とを、前記電源装置を３
相としてそれぞれ３系統有してなる３相電子的負荷装置
において、 前記負荷特性設定値として下記数１で示される如き電力
系統において取得される負荷動特性モデルを用い、電圧
の変動に対する電力変動量を模擬可能にしてなることを
特徴とする３相電子的負荷装置。 【数１】 （なお、Ｐ（ｉ），Ｑ（ｉ）はそれぞれ負荷のとる有効
電力，無効電力、Ｐ0 ，Ｑ0 はそれぞれの初期値、Ｖ
（ｉ）は時刻ｉでの系統電圧実効値、Ｖ0 はその初期
値、Ｖk ，Ｖk-1 はそれぞれ時刻ｋ，ｋ−１での系統電
圧実効値、ｎp ，ｎq は静的な電圧特性係数設定パラメ
ータ、Ａｐ，Ａｑは電圧過渡変動に対する電力の過渡変
動相当量の設定パラメータ、Ｔｐ，Ｔｑは時定数設定パ
ラメータ、Ｋ0 は定数、ｅは指数関数、Δｔは演算周期
をそれぞれ示している。）1. An A / D converter for converting a sampling value of an input voltage from a power supply device into a digital signal, a digital operation device for calculating a load current set value according to the digital signal and a load characteristic set value, and The D / A converter for converting the load current set value into an analog signal and the current source connected to the power supply device for generating a load current based on the analog signal are connected to the power supply device 3
In a three-phase electronic load device having three systems each as a phase, a load dynamic characteristic model acquired in the power system as shown in the following mathematical expression 1 is used as the load characteristic set value, and a power variation amount with respect to a voltage variation is used. A three-phase electronic load device characterized by being capable of simulating. [Equation 1] (Note that P (i) and Q (i) are active power and reactive power respectively taken by the load, P 0 and Q 0 are respective initial values, V
(I) is the effective value of the system voltage at time i, V 0 is its initial value, V k and V k-1 are the effective values of the system voltage at times k and k-1, respectively, and n p and n q are static. Voltage characteristic coefficient setting parameters, Ap, Aq are setting parameters of the amount of transient fluctuation of electric power with respect to voltage transient fluctuations, Tp, Tq are time constant setting parameters, K 0 is a constant, e is an exponential function, and Δt is a calculation cycle. Shows. )
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP3264341A JP2919657B2 (en) | 1991-10-14 | 1991-10-14 | Three-phase electronic load |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP3264341A JP2919657B2 (en) | 1991-10-14 | 1991-10-14 | Three-phase electronic load |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH0599969A true JPH0599969A (en) | 1993-04-23 |
| JP2919657B2 JP2919657B2 (en) | 1999-07-12 |
Family
ID=17401825
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP3264341A Expired - Lifetime JP2919657B2 (en) | 1991-10-14 | 1991-10-14 | Three-phase electronic load |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP2919657B2 (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH11252796A (en) * | 1998-03-02 | 1999-09-17 | Kansai Electric Power Co Inc:The | Power system higher harmonic real-time simulator |
| US6153657A (en) * | 1997-06-02 | 2000-11-28 | Hodogaya Chemical Co., Ltd. | Process for producing a solvent-less O/W type emulsion |
-
1991
- 1991-10-14 JP JP3264341A patent/JP2919657B2/en not_active Expired - Lifetime
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6153657A (en) * | 1997-06-02 | 2000-11-28 | Hodogaya Chemical Co., Ltd. | Process for producing a solvent-less O/W type emulsion |
| JPH11252796A (en) * | 1998-03-02 | 1999-09-17 | Kansai Electric Power Co Inc:The | Power system higher harmonic real-time simulator |
Also Published As
| Publication number | Publication date |
|---|---|
| JP2919657B2 (en) | 1999-07-12 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| EP0445713B1 (en) | Electric power system simulator | |
| JP3392506B2 (en) | Solar power generation simulator | |
| JPH0599969A (en) | Three phase electronlike loading device | |
| Marín et al. | Modelling of stick–slip behaviour in a Girling brake using network simulation method | |
| JP2006234457A (en) | Three-phase four-wire system load simulator | |
| JP3343709B2 (en) | Power system analyzer | |
| Huang et al. | Discrete modeling and period-adding bifurcation of DC–DC converter feeding constant power load | |
| Brambilla et al. | The simulation errors introduced by the spice transient analysis | |
| US3772505A (en) | System and method for on-line simulation of bulk power system transients at very high speeds | |
| US7283943B1 (en) | Method of modeling circuit cells for powergrid analysis | |
| JP2703091B2 (en) | Power system simulator | |
| US4878009A (en) | Voltage source having preset values for source voltage and internal resistance | |
| Karplus | The use of electronic analogue computers with resistance network analogues | |
| Ajjarapu | Application of bifurcation and continuation methods for the analysis of power system dynamics | |
| CN113343453B (en) | Modeling method of power electronic cascade converter based on small-step discretization | |
| Ibrahim et al. | Frequency dependent network equivalent algorithm for AC power systems | |
| D'amore et al. | Steady state analysis of nonlinear circuits using SPICE | |
| Negi et al. | Design and Performance Analysis of FPGA based Fractional-PID Controller | |
| JP3142072B2 (en) | Digital defuzzifier circuit | |
| US2983448A (en) | Trigonometric function generator | |
| JP2691070B2 (en) | Electronic reactor | |
| JP3095798B2 (en) | Analog back-propagation learning circuit and its driving method | |
| Alboaouh et al. | Time domain modeling of constant power loads for electromagnetic transient simulations | |
| JP2003022295A (en) | Method and device for simulating effective value impedance and program for simulating effective value impedance | |
| Kalra et al. | Reduced modelling of transmission line circuits using a novel nonlinearity aware tpwl with adaptive sampling |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| R250 | Receipt of annual fees |
Free format text: JAPANESE INTERMEDIATE CODE: R250 |
|
| R250 | Receipt of annual fees |
Free format text: JAPANESE INTERMEDIATE CODE: R250 |
|
| R250 | Receipt of annual fees |
Free format text: JAPANESE INTERMEDIATE CODE: R250 |
|
| R250 | Receipt of annual fees |
Free format text: JAPANESE INTERMEDIATE CODE: R250 |
|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20080423 Year of fee payment: 9 |
|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20090423 Year of fee payment: 10 |
|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20100423 Year of fee payment: 11 |
|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20110423 Year of fee payment: 12 |
|
| EXPY | Cancellation because of completion of term | ||
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20120423 Year of fee payment: 13 |