JP2013190895A - Arbitrary characteristic circuit synthesis method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an arbitrary characteristic circuit synthesis method having a high versatility and capable of synthesizing a circuit having a characteristic that does not exist in reality.SOLUTION: An arbitrary characteristic circuit synthesis method of this invention is a method for synthesizing a circuit having an arbitrary characteristic by using a system which comprises: a main circuit part including an inverter circuit and an energy storage element; a reference signal generation part which generates a reference signal regarding the terminal current/terminal voltage of the main circuit part on the basis of a measured terminal current/terminal voltage; and a control part which controls the inverter circuit so that the terminal current/terminal voltage of the main circuit part coincides with the reference signal. When measuring the terminal voltage, a reference signal regarding the terminal current is generated on the basis of the predetermined admittance characteristic of the circuit and the measured terminal voltage. On the other hand, when measuring the terminal current, a reference signal regarding the terminal voltage is generated on the basis of the predetermined impedance characteristic of the circuit and the measured terminal current.

Description

  The present invention relates to a method for synthesizing a circuit having an arbitrary characteristic by appropriately controlling a main circuit unit including an inverter circuit and an energy storage element.

The characteristic in the time domain of an arbitrary linear one-terminal pair circuit can be represented by a transient admittance y (t) or a transient impedance z (t) as shown in FIG. When the time functions of the terminal voltage and terminal current of the circuit are v (t) and i (t), respectively, the relationship between the terminal current i (t) and the terminal voltage v (t) is expressed by It becomes.

Moreover, the characteristic in the frequency domain of an arbitrary linear one-terminal pair circuit can be represented by an admittance function Y (s) or an impedance function Z (s) as shown in FIG. When the frequency functions of the terminal voltage and the terminal current of the circuit are V (s) and I (s), the relationship between the terminal current I (s) and the terminal voltage V (s) is as follows. However, s = jω where ω is an angular frequency.

  As a conventional method for synthesizing a circuit having an arbitrary characteristic, a characteristic of the entire circuit is a desired admittance characteristic (y (t), Y (s)) or an impedance characteristic (z (t), Z (s)). There is a method of combining a plurality of circuit elements (resistors, capacitors, inductors, etc.). However, this conventional synthesis method has a problem that it is necessary to recombine specific circuit elements when changing characteristics. In addition, this synthesis method has a problem that a circuit having characteristics that do not actually exist (for example, a negative inductor) cannot be synthesized.

  As a synthesis method capable of synthesizing a negative inductor, a method described in Non-Patent Document 1 is known. However, this synthesis method is a synthesis method specialized for synthesis of negative inductors using a feedback circuit composed of analog components including an operational amplifier and an analog multiplier, and is not highly versatile.

Hirohito Funato, Atsuo Kawamura and Kenzo Kamiyama, "Realization of Negative Inductance Using Variable Active-Passive Reactance (VAPAR)", IEEE Transactions on Power Electronics, July 1997, Vol.12, No.4, pp.589-596

  The present invention has been made in view of the above circumstances, and an object thereof is to provide an arbitrary characteristic circuit synthesizing method capable of synthesizing a circuit having high versatility and characteristics that do not actually exist. There is.

  In order to solve the above problems, an arbitrary characteristic circuit synthesis method according to the present invention includes a main circuit unit including an inverter circuit and an energy storage element, and a main circuit unit based on the measured terminal voltage or terminal current of the main circuit unit. A system comprising a reference signal generation unit that generates a reference signal related to a terminal current or a terminal voltage, and a control unit that controls a switching element of the inverter circuit so that the terminal current or the terminal voltage of the main circuit unit matches the reference signal is used. And (a) when measuring the terminal voltage of the main circuit unit, the admittance characteristic of the circuit previously determined by the reference signal generation unit and the measured terminal (B) On the other hand, when measuring the terminal current of the main circuit unit based on the voltage, the reference signal generating unit obtains the reference signal in advance. And generating a reference signal related to the terminal voltage based on the impedance characteristic and the measured terminal current of the circuit.

  In the arbitrary characteristic circuit synthesizing method, the reference signal generation unit can be constituted by a digital filter. In this case, the digital filter is preferably one that takes into account control delays in the reference signal generation unit and the control unit.

  Note that (a) when measuring the terminal voltage of the main circuit section, an inductor is used as the energy storage element, and (b) when measuring the terminal current of the main circuit section, a capacitor is used as the energy storage element. Good.

  According to the present invention, it is possible to provide an arbitrary characteristic circuit synthesis method capable of synthesizing a circuit having high versatility and having characteristics that do not actually exist.

It is a figure which shows the relationship between a terminal current and a terminal voltage, Comprising: (A) is a related figure in a time domain, (B) is a related figure in a frequency domain. It is a circuit diagram of the main circuit part used with the arbitrary characteristic circuit composition method concerning the present invention, and (A) is the main circuit part used when performing admittance type composition, and (B) performs impedance type composition. It is a main circuit part used in the case. It is the circuit diagram of the simplified main circuit part used with the arbitrary characteristic circuit synthetic | combination method based on this invention, Comprising: (A) is the main circuit part used when performing admittance type composition, (B) is an impedance type This is a main circuit unit used in the case of performing synthesis. 1 is a block diagram of a system used in an arbitrary characteristic circuit synthesis method according to the present invention, in which (A) is a system in which both a reference signal generation unit and a control unit perform digital processing, and (B) is a reference signal generation unit. (C) is a system in which both the reference signal generation unit and the control unit perform analog processing. FIG. 2 is a block diagram of a control unit used in the arbitrary characteristic circuit synthesis method according to the present invention, where (A) is a control unit configured by a circuit that performs analog processing, and (B) is a circuit that performs digital processing. It is a control unit. FIG. 3 is a block diagram of a reference signal generation unit configured by a circuit that performs analog processing, which is used in the arbitrary characteristic circuit synthesis method according to the present invention. FIG. 3 is a block diagram of a reference signal generation unit configured by a circuit that performs digital processing, which is used in the arbitrary characteristic circuit synthesis method according to the present invention. 6 is a block diagram of a reference signal generation unit according to Synthesis Example 1. FIG. 6 is a circuit diagram showing an experimental system according to Synthesis Example 1. FIG. 6 is a waveform diagram showing experimental results according to Synthesis Example 1. FIG. 6 is a waveform diagram showing experimental results according to Synthesis Example 1. FIG. FIG. 4 is a circuit diagram of an LCR circuit according to Synthesis Example 2, in which (A) is a circuit diagram of an LCR circuit to be synthesized, and (B) is an equivalent circuit diagram of (A). 10 is a block diagram of a reference signal generation unit according to Synthesis Example 2. FIG. 10 is a circuit diagram showing an experimental system according to Synthesis Example 2. FIG. It is a wave form diagram which shows the experimental result which concerns on the synthesis example 2. FIG. It is a wave form diagram which shows the experimental result which concerns on the synthesis example 2. FIG. It is the waveform measured in order to produce a digital filter, Comprising: (A) is the waveform figure before fitting, (B) is the waveform figure after fitting. It is a wave form diagram which shows the experimental result which concerns on the synthesis example 3. FIG. It is the waveform measured in order to produce a digital filter, Comprising: (A) is the waveform figure before fitting, (B) is the waveform figure after fitting. It is a wave form diagram which shows the experimental result which concerns on the synthesis example 3. FIG. It is a block diagram of a reference signal generation unit for synthesizing a 4-terminal circuit.

  Hereinafter, embodiments of an arbitrary characteristic circuit synthesis method according to the present invention will be described with reference to the accompanying drawings.

[Entire system configuration]
In the method for synthesizing an arbitrary characteristic circuit according to the present invention, a main circuit unit including an inverter circuit and an energy storage element, and a reference signal related to the terminal current or terminal voltage of the main circuit unit based on the measured terminal voltage or terminal current of the main circuit unit And a control unit that controls the inverter circuit so that the terminal current or the terminal voltage of the main circuit unit matches the reference signal.

  FIG. 2 shows an example of the main circuit unit. FIG. 2A shows a main circuit unit used when admittance-type synthesis is performed, that is, when synthesis is performed by controlling the switching elements of the inverter circuit so as to have a desired admittance characteristic (y (t)). is there. As shown in the figure, the main circuit section includes a voltage-type inverter circuit including four switch elements and four diodes, an inductor as an energy storage element, and a DC voltage source. On the other hand, FIG. 2B shows a main circuit used in the case of performing impedance-type synthesis, that is, in the case of performing synthesis by controlling the switching elements of the inverter circuit so as to have a desired impedance characteristic (z (t)). Part. As shown in the figure, the main circuit section includes a current source inverter circuit including four switch elements and four diodes, a capacitor as an energy storage element, and a direct current source.

  As described with reference to FIGS. 1 and (1), when admittance synthesis is performed, the terminal voltage v (t) is measured, and the terminal current is matched with v (t) * y (t). i (t) is controlled. On the other hand, when the impedance type is synthesized, the terminal current i (t) is measured, and the terminal voltage v (t) is controlled so as to match i (t) * z (t).

  If the circuit to be synthesized does not have a resistance component and energy is not consumed and regenerated in the synthesis circuit, the DC voltage source or DC current source in the main circuit section is replaced with a capacitor or inductor to simplify the configuration. (See FIG. 3).

FIG. 4 shows the overall configuration of a system used in the admittance synthesis method according to the present invention. As described above, the system used in the present invention includes a reference signal generation unit that generates the reference signal x ^* (t) or x ^* [k] in addition to the main circuit unit illustrated in FIGS. And a control unit for controlling the switch element. The reference signal generation unit generates a reference signal i ^* (t) or i ^* [k] related to the terminal current i (t) when performing admittance type synthesis, and the terminal voltage v when performing impedance type synthesis. A reference signal v ^* (t) or v ^* [k] for (t) is generated.

FIG. 4A shows a system in which both the reference signal generation unit and the control unit are configured by a circuit that performs digital processing. In this case, the reference signal generation unit obtains the reference signal i ^* [k] based on the AD converter that AD converts the measured terminal voltage v (t) and the terminal voltage v [k] obtained by the AD conversion. And a digital processing unit (for example, DSP (Digital Signal Processor)) to be generated. In addition, the control unit generates a control signal u [k] that matches the terminal current i [k] obtained by AD conversion of the actual terminal current i (t) with the reference signal i ^* [k]. A digital control unit (for example, a DSP), and a DA converter that converts the control signal u [k] into the control signal u (t). The inverter circuit of the main circuit unit is controlled by this control signal u (t).

  4B shows a system in which the reference signal generation unit is configured by a circuit that performs analog processing, and FIG. 4C illustrates that both the reference signal generation unit and the control unit are configured by circuits that perform analog processing. This is the system when Although not shown, only the control unit can be configured by a circuit that performs analog processing. That is, in the admittance type synthesis method according to the present invention, four systems can be used.

  Naturally, four types of systems can also be used in the impedance type synthesis method according to the present invention. When combining impedance types, it is only necessary to change the configuration of the main circuit part and replace symbols representing terminal voltage and terminal current.

[Configuration of control unit]
Next, a specific configuration of the control unit will be described with reference to FIG.

(Control unit composed of analog processing circuits)
FIG. 5A illustrates an example of a control unit including a circuit that performs analog processing. As shown in the figure, this control unit performs state feedback control of the main circuit unit and performs second-order integral compensation. The reason why the compensation is secondary is that the primary compensation can only compensate to a constant value and cannot follow the dynamic change of the reference signal x ^* (t). In the example of FIG. 5A, the main circuit unit includes a DC voltage source or a DC current source (see FIG. 2), and the main circuit unit itself performs the primary compensation. Compensation is third order. Therefore, there are three feedback gains, f, g ₁ , and g ₂ . The order and configuration of the compensator can be appropriately changed as necessary. For example, a higher order or a sine wave compensator may be combined.

また、この制御系の特性方程式は次式となる。

（３）式および（４）式中のフィードバックゲインｆ、ｇ_１、ｇ_２は、例えば、極配置法や最適制御法により決定することができる。 The state equation of the control system shown in FIG. 5A is as follows when the state transition matrix and the input vector of the main circuit unit are A _c and h _c , respectively.

The characteristic equation of this control system is as follows.

The feedback gains f, g ₁ , and g ₂ in the equations (3) and (4) can be determined by, for example, a pole placement method or an optimal control method.

また、この制御系の特性方程式は次式となる。

アナログ的処理を行う回路で制御部を構成した場合と同様、（５）式および（６）式中のフィードバックゲインｆ、ｇ_１、ｇ_２は、例えば、極配置法や最適制御法により決定することができる。 (Control unit composed of digital processing circuits)
FIG. 5B is an example of a control unit configured by a circuit that performs digital processing. Assuming that the state transition matrix is A, the input vector is h, and the sampling time interval is T, the state equation of this control system at the sampling time t = t [k] = kT is as follows.

The characteristic equation of this control system is as follows.

The feedback gains f, g ₁ , and g ₂ in the equations (5) and (6) are determined by, for example, the pole placement method or the optimal control method, as in the case where the control unit is configured by a circuit that performs analog processing. be able to.

[Configuration of reference signal generator]
Next, a specific configuration of the reference signal generation unit will be described. Here, a reference signal generation unit used in the case of performing admittance type synthesis will be described. This reference signal generation unit replaces the relationship between the terminal current and the terminal current and simply converts the corresponding symbol to change the impedance type. This is a reference signal generation unit used when combining the above.

ここで、Ｃ_０、Ｇ_０は定数、ａ_１ｋ、ａ_０ｋ、ｂ_１ｋ、_０ｋ（ｋ＝１，２，・・・，Ｎ_ｃ）はＮ_ｃ個の２次分数多項式に対する係数、ａ_ｒｋ、ｂ_ｒｋ（ｋ＝１，２，・・・，Ｎ_ｓ）はＮ_ｓ個の１次分数多項式に対する係数である。 (Reference signal generator composed of circuits that perform analog processing)
The admittance characteristic Y (s) in the frequency domain can be expressed by the following equation.

Here, C ₀ and G ₀ are constants, a _1k , a _0k , b _1k , and _0k (k = 1, 2,..., N _c ) are coefficients for N _c second-order fractional polynomials, a _rk , b _rk (k = 1, 2,..., N _s ) is a coefficient for N _s first-order fractional polynomials.

FIG. 6 shows a block diagram of a reference signal generation unit that generates a reference signal i ^* (t) related to a terminal current based on the measured terminal voltage v (t) and the admittance characteristic Y (s). As shown in the figure, in this reference signal generation unit, processing corresponding to each term of equation (7) is performed in parallel. That is, in this reference signal generation unit, a block corresponding to sC ₀ , a block corresponding to G ₀ , a block of N _c stages corresponding to a second-order fractional polynomial, and N _s stages corresponding to a first-order fractional polynomial The block is connected in parallel. The reference signal generation unit outputs a reference signal i ^* (t) related to the terminal current.

In addition, when the impedance type is synthesized, an impedance characteristic Z (s) represented by the following expression may be used instead of the admittance characteristic Y (s) represented by the expression (7).

(Reference signal generator composed of digital processing circuits)
When the reference signal generation unit is configured by a circuit that performs digital processing, a feedback system may be configured using a time delay element instead of an integration element.

By the way, in the reference signal generating unit configured as described above and the reference signal generating unit configured by the circuit that performs the analog processing, for example, between the reference signal and the actual signal, for example, the reference signal i ^* (t) and the actual signal Deviation (control delay) occurs with respect to the terminal current i (t). Therefore, hereinafter, a reference signal generation unit configured with a digital filter capable of canceling the control delay will be described.

すなわち、次式が成立する。

When a reference signal generation unit configured by a circuit that performs digital processing is used and admittance synthesis is performed, a terminal current transfer function I [z], a terminal voltage transfer function V [z], and an admittance function Y [z ] Is established in the formula (9).

That is, the following equation is established.

したがって、アドミタンス関数Ｙ［ｚ］をＩＩＲディジタルフィルタで構成すれば、基準信号生成部のブロック図は図７に示す通りとなる。 Here, the admittance function Y [z] is as follows.

Therefore, if the admittance function Y [z] is configured by an IIR digital filter, the block diagram of the reference signal generation unit is as shown in FIG.

ここで、（１４）式の各ベクトルは、１周期中の各Ｎ個の端子電流ｉ［ｋ］、端子電圧ｖ［ｋ］（ｋ＝０，１，・・・，Ｎ−１）のサンプル点より合成すれば、次式となる。

The coefficients a ₁ , a ₂ ,..., A _Ni and the coefficients b ₁ , b ₂ ,..., B _Nv in the _equations of FIG. That is, by substituting equation (11) into equation (9) and paying the denominator, equations (12) and (13) are obtained, and furthermore, equation (13) is rewritten using a vector to obtain.

Here, each vector of the equation (14) is a sample of N terminal currents i [k] and terminal voltages v [k] (k = 0, 1,..., N−1) in one cycle. If synthesized from points, the following equation is obtained.

すなわち、図７および（１１）式における係数ａ_１，ａ_２，・・・，ａ_Ｎｉおよび係数ｂ_１，ｂ_２，・・・，ｂ_Ｎｖを決定することができる。 The coefficient vector x can be obtained by using the least square method for the equation (14).

That is, the coefficients a ₁ , a ₂ ,..., A _Ni and the coefficients b ₁ , b _{2 ,.}

[Synthesis Example 1: Negative Inductor]
According to the synthesis method of the present invention, a circuit having an arbitrary characteristic can be synthesized. As an example, a result of an experiment in which a negative inductor of −5 mH is synthesized using the system shown in FIG. Will be described. In addition, since the frequency characteristic of the negative inductor attenuates in a high frequency region, an admittance type synthesis was performed in this synthesis example.

上記（１９）式をサンプル時間Ｔで離散化すると、（２０）式が得られる。

したがって、基準信号ｉ^＊［ｋ］を生成するための基準信号生成部の構成は、図８に示す通りとなる。ただし、図８中のＬは−５ｍＨである。 Since the circuit to be synthesized is a negative inductor, the terminal currents i (t) and I (s) are proportional to the integrals of the terminal voltages v (t) and V (s), respectively. Therefore, the following equation is established.

When the equation (19) is discretized with the sample time T, the equation (20) is obtained.

Therefore, the configuration of the reference signal generation unit for generating the reference signal i ^* [k] is as shown in FIG. However, L in FIG. 8 is −5 mH.

  The experimental system used in this synthesis example is shown in FIG. As shown in the figure, the main circuit section includes an inverter circuit, an inductor as an energy storage element, a resistor connected in series to the inductor, and a DC voltage source. Further, a voltage source capable of outputting an arbitrary voltage waveform (in this synthesis example, a sine wave and a rectangular wave) is connected between the terminals of the main circuit unit. The resistor is provided for current limiting.

なお、記号ｆ_ｓは、インバータ回路の制御周波数である。 The nominal values of the experimental parameters are as shown in the table below.

The symbol f _s is the control frequency of the inverter circuit.

FIG. 10 shows a reference signal i ^* corresponding to a negative inductor of −5 mH while measuring a terminal voltage (input voltage v _in ) of an arbitrary voltage waveform to be input as a sine wave (amplitude 5 V, 50 Hz). This is a result of PWM control of the terminal current (inductor current i _{L in} FIG. 9) by the inverter circuit so as to follow, among which (A) in FIG. 9 is taken in by the DSP constituting the reference signal generation unit and the control unit. The terminal voltage v _in , the terminal current i _L and the waveform of the reference signal i ^* generated in the DSP. From this figure, the terminals current i _L is approximately equal to the reference signal i ^*, and terminal current i _L is proceeding 90 ° with respect to the terminal voltage v _in, and able to reproduce the characteristics of the negative inductor I understand that.

Further, FIG. (B) is a waveform of the terminal voltage measured by oscilloscope v _in and the terminal current i _L. From also this figure, terminal current i _L is proceeding 90 ° with respect to the terminal voltage v _in, it can be seen that can reproduce the characteristics of negative inductor.

FIG. 11 shows the experimental results when the input arbitrary voltage waveform is a rectangular wave (amplitude 5 V, 50 Hz). Among these, FIG. 11A shows the terminal voltage v _in and the terminal current i captured by the DSP. reference signal generated by the _L and DSP ^{i *} of the waveform, FIG. (B) is a waveform of the terminal voltage measured by oscilloscope _{v in} and the terminal current _{i L.} As in the case of the sine wave, it can be seen from these figures that the terminal current i _L substantially matches the reference signal i ^* .

[Synthesis Example 2: LCR circuit]
Next, experimental results obtained by synthesizing the LCR circuit shown in FIG. 12A using the system shown in FIG. Since the frequency characteristics of the LCR circuit are attenuated in the high frequency range, admittance type synthesis was performed in this synthesis example.

したがって、本合成例では、基準信号生成部を図１３に示すブロック図で構成すればよい。なお、（２１）式および図１３における素子値は下表の通りである。

Since the equivalent circuit of the LCR circuit is as shown in FIG. 12B, the admittance characteristic Y (s) of the LCR circuit to be synthesized can be expressed by the following equation.

Therefore, in this synthesis example, the reference signal generation unit may be configured by the block diagram shown in FIG. The element values in the equation (21) and FIG. 13 are as shown in the table below.

なお、記号ｆ_ｓは、インバータ回路の制御周波数である。 The experimental system is as shown in FIG. 14 and has a configuration in which an LCR circuit is further added to the experimental system used in Synthesis Example 1. With this configuration, does the current i _syn (hereinafter referred to as terminal current) flowing from the voltage source toward the main circuit unit match the current i _LCR flowing toward the actual LCR circuit? It is possible to determine whether or not the characteristics of the circuit obtained by the synthesis match the characteristics of the actual LCR circuit. The nominal values of the experimental parameters are as shown in the table below.

The symbol f _s is the control frequency of the inverter circuit.

FIG. 15 shows that an arbitrary voltage waveform to be input is a sine wave (amplitude 5 V, 50 Hz), and follows a reference signal i ^* corresponding to the LCR circuit while measuring a terminal voltage (input voltage vin _in FIG. 14). The result of the PWM control of the terminal current i _syn by the inverter circuit is shown in FIG. 5A. The figure (A) shows the terminal current i _syn taken in the DSP constituting the reference signal generation unit and the control unit, and is generated in the DSP. _Is a waveform of the reference signal i ^* and the current i _LCR . From this figure, it can be seen that the terminal current i _syn and the current i _LCR substantially match, and a desired LCR circuit can be synthesized.

FIG. 5B shows waveforms of the terminal current i _syn and current i _LCR measured with an oscilloscope. Also from this figure, it can be seen that the terminal current i _syn and the current i _LCR substantially match, and a desired LCR circuit can be synthesized.

FIG. 16 shows the experimental results when the arbitrary voltage waveform to be input is a rectangular wave (amplitude 5 V, 50 Hz). Of these, FIG. 16A shows the terminal current i _syn taken into the DSP and the DSP. Waveforms of the generated reference signal i ^* and current i _LCR , FIG. 5B are waveforms of the terminal current i _syn and current i _LCR measured with an oscilloscope. In any of the figures, the terminal current i _syn is slightly behind the current i _LCR, and the overshoot amount is also slightly larger. This is because when the arbitrary voltage waveform is a rectangular wave, the influence of the control delay appears more remarkably. This control delay can be improved by performing synthesis using a digital filter described later.

[Synthesis Example 3: LCR circuit]
Next, an experimental result of synthesizing the same LCR circuit (see FIG. 14, Table 3) as in Synthesis Example 2 using a digital filter that is considered so as to cancel the control delay will be described.

To create a digital filter, first, in the experimental system shown in FIG. 14, a sinusoidal terminal voltage _{v in} to enter (amplitude 5V, 50 Hz) and was current _{i LCR} (hereinafter flowing toward the LCR circuit side when the And the terminal current i _syn when the reference signal i ^* is the terminal voltage v _in / R (where R is a scale factor). The result of this measurement is shown in FIG.

また、伝達関数Ｉ_ｓｙｎ［ｚ］を実電流ｉ_ＬＣＲの伝達関数Ｉ_ＬＣＲ［ｚ］に一致させるための補正伝達関数をＦ［ｚ］とすると、（２３）式および（２４）式が成立する。

When a delay transfer function of the reference signal ^{i *} with respect to terminal currents _{i syn} and H [z], between the transfer function _{I syn} [z] and the reference signal ^{i *} of the transfer function ^I * [z] of the terminal current _{i syn} The following equation holds.

Further, when the correction transfer function for making the transfer function I _syn [z] coincide with the transfer function I _LCR [z] of the actual current i _LCR is F [z], the equations (23) and (24) are established. .

The coefficient of the corrected transfer function F [z], that is, the coefficient of the digital filter used in this synthesis example can be obtained by the equation (18). More specifically, the coefficient of the digital filter is the delay included in I _syn [z] so that the terminal current i _syn shown in FIG. 17A matches the actual current i _LCR shown in FIG. It can be obtained by correcting the transfer function H [z]. Table 4 shows the coefficients thus obtained (where N _i = 6, N _v = 5).

When the same measurement as that obtained in FIG. 17A was performed using a digital filter (see FIG. 7) created using the above coefficients, FIG. 17B was obtained. From this figure, it can be seen that the terminal current i _syn substantially matches the actual current i _LCR as a result of the fitting.

FIG. 18 shows the experimental results using this digital filter. The figure shows that the delay of the terminal current i _syn with respect to the actual current i _LCR is reduced and the followability is improved as compared with the case where the digital filter is not used (see FIG. 15B).

この係数を用いて作成したディジタルフィルタ（図７参照）を使用したフィッティングの結果を図１９に示す。同図（Ａ）に示すフィッティング前に比べ、同図（Ｂ）に示すフィッティング後では、実電流ｉ_ＬＣＲに対する端子電流ｉ_ｓｙｎの遅れが低減され、追従性が向上したことが分かる。 When the terminal voltage _{v in} to input square wave (amplitude 5V, 50 Hz) and is in the same manner, coefficients shown in Table 5 _{(where, N i = 4, N v} = 4) were obtained.

FIG. 19 shows the result of fitting using a digital filter (see FIG. 7) created using this coefficient. It can be seen that the delay of the terminal current i _syn with respect to the actual current i _LCR is reduced and the followability is improved after the fitting shown in FIG.

FIG. 20 shows the experimental results using this digital filter. This figure also shows that the delay of the terminal current i _syn with respect to the actual current i _LCR is reduced and the followability is improved as compared with the case where the digital filter is not used (see FIG. 16B).

  The embodiment of the arbitrary characteristic circuit synthesis method according to the present invention has been described above. However, the present invention is not limited to the above-described configuration, and various modifications can be considered.

For example, the arbitrary characteristic circuit synthesis method according to the present invention can also synthesize another terminal circuit having an arbitrary characteristic. By way of example, 4 because in the case of the terminal circuit holds the following equation, the reference signal generation unit In the structure shown in FIG. 21, based on the terminal voltage v ₁ of the terminals _{(t) ~v} 1 _(t) Reference signals i ^* ₁ (t) to i ^* ₄ (t) relating to the terminal current of each terminal can be generated. However, in FIG. 21, for example, y ₁₁ (t) is expressed by the transfer characteristic Y11 (s) = Y11.

  In the synthesis example 3, the control delay is canceled by the digital filter. However, in the arbitrary characteristic circuit synthesis method according to the present invention, the control delay is canceled by using the reference signal generation unit configured by the circuit that performs analog processing. You can also.

Claims (4)

A main circuit unit including an inverter circuit and an energy storage element; a reference signal generating unit that generates a reference signal related to the terminal current or terminal voltage of the main circuit unit based on the measured terminal voltage or terminal current of the main circuit unit; A method of synthesizing a circuit having arbitrary characteristics using a system including a control unit that controls a switching element of the inverter circuit so that a terminal current or a terminal voltage of the main circuit unit matches the reference signal. ,
When measuring the terminal voltage of the main circuit part,
The reference signal generation unit generates a reference signal related to a terminal current based on the admittance characteristics of the circuit obtained in advance and the measured terminal voltage,
On the other hand, when measuring the terminal current of the main circuit part,
The reference signal generation unit generates a reference signal related to a terminal voltage based on the impedance characteristics of the circuit obtained in advance and the measured terminal current;
A method of synthesizing an arbitrary characteristic circuit.   2. The method for synthesizing an arbitrary characteristic circuit according to claim 1, wherein the reference signal generation unit comprises a digital filter.   3. The arbitrary characteristic circuit synthesis method according to claim 2, wherein the digital filter takes into account a control delay in the reference signal generation unit and the control unit.   When measuring the terminal voltage of the main circuit section, an inductor is used as the energy storage element, and when measuring the terminal current of the main circuit section, a capacitor is used as the energy storage element. 4. The method of synthesizing an arbitrary characteristic circuit according to claim 1.

Images