JP2909377B2 - Control device for voltage source PWM converter - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a voltage-type PWM converter control apparatus for controlling an output DC voltage and an input-side reactive current of a voltage-type PWM converter.

[0002]

2. Description of the Related Art A voltage-type PWM converter has a power factor of 1 unit.
It can be operated, has low harmonic current, and can regenerate power supply. For high-performance operation of this voltage-type PWM converter, the DC voltage on the output side can be controlled with high accuracy. In order to operate at a power factor of 1, the reactive current on the input side is reduced to zero at high speed and high accuracy. It is important to be able to control.

FIG. 6 shows a method (lecture number 33) announced at the 1991 IEEJ National Conference on Industrial Applications as a method of controlling the DC voltage on the output side and the reactive current on the input side of a voltage-type PWM converter. FIG. 3 is a configuration diagram in which only the control device portion of the voltage-type PWM converter is extracted from FIG. In FIG. 6, 1 is a voltage-type PWM converter, 2 is a voltage-type inverter, 3 is a converter transformer, and the voltage-type PWM converter 1 is connected to a power supply system via this transformer. Reference numeral 4 denotes a load connected to the voltage source inverter 2, which is, for example, an AC motor such as an induction motor or a synchronous motor. 5 is a DC smoothing capacitor, 6 is a DC voltage detector, 7 is a DC current detector, 8, 9, and 10 are input current detectors that detect AC current flowing from the power supply system to the voltage-type PWM converter 1, 11, 12 , 13 are input voltage detectors for detecting the AC voltage of the power supply system.

Next, the configuration of the control device will be described. Reference numeral 14 denotes an input current coordinate converter for converting the converter input current detected by the input current detectors 8, 9, and 10 into a rotating coordinate system (d-axis and q-axis coordinate systems) synchronized with the power supply voltage. Is converted into an active current component (d-axis current component) having the same phase as that of the input current and a reactive current component (q-axis current component) shifted by 90 ° from the phase of the input side AC current. Reference numeral 15 denotes an input voltage coordinate converter for converting the input voltage detected by the input voltage detectors 11, 12, and 13 into a rotary coordinate system also synchronized with the power supply voltage. , Q-axis voltage becomes zero.

A DC voltage commander 16 outputs a command value of a DC voltage on the output side of the voltage-type PWM converter 1.
Reference numeral 9 denotes a subtractor that calculates the difference between the DC voltage command value and the DC voltage detection value from the DC voltage detector 6, and 34 denotes a DC voltage controller that amplifies the subtraction result of the subtractor 19, but in the case of a proportional integrator. There are many. 35 is a conversion coefficient unit for converting the DC current detection value from the DC current detector 7 into an effective current component of the converter input current, and 36 is an adder for adding the output of the DC voltage controller 34 and the output of the conversion coefficient unit 35. The addition result becomes an effective current command value (d-axis current command value) of the converter input current. 37 is the effective current command value and the input current coordinate converter 1
A subtractor 38 for obtaining a difference from the effective current output value from 4 is an effective current controller (d-axis current controller) for amplifying the subtraction result of the subtractor 37, and is often a proportional integrator. An adder 40 adds the output of the effective current integrator 38 and the d-axis voltage value from the input voltage coordinate converter 15, and the addition result becomes a d-axis voltage command value to be generated by the voltage-type PWM converter 1. .

Further, 17 is a voltage type PWM converter 1
When the operation is performed at a power factor of 1, a zero command is output. 21 is a subtractor for calculating the difference between the reactive current command value and the reactive current output value from the input current coordinate converter 14;
Is a reactive current controller (q
Shaft current controller), which is often a proportional integrator. 4
1 is the output of the reactive current controller 39 and the input voltage coordinate converter 1
This is an adder for adding the q-axis voltage value from 5 to the q-axis voltage command value to be generated by the voltage-type PWM converter 1. Reference numeral 28 denotes a voltage type P using the d-axis voltage command value from the adder 40 and the q-axis voltage command value from the adder 41.
A coordinate inverse converter 29 for outputting an actual modulation ratio command of the WM converter 1; a PWM gate control 29 for performing PWM control based on the modulation ratio command from the coordinate inverse converter 28 and outputting a gate pulse of the voltage-type PWM converter 1 It is a vessel.

Next, the operation according to the above configuration will be described. First, regarding the control of the input-side reactive current, the q-axis voltage command such that the reactive current flows according to the reactive current command value through the route of the reactive current commander 17, the subtractor 21, the reactive current controller 39, and the adder 41. The value is output and is reflected on the actual gate pulse by the coordinate inverter 28 and the PWM gate controller 29. Thereby, the voltage type PWM converter 1, the converter transformer 3, the input current detector 8,
The reactive current flowing due to the generation of the gate pulse is fed back via the input current coordinate converter 14, and the input current coordinate converter 14 matches the reactive current command value again and is reflected on the gate pulse.

That is, in FIG. 6, a voltage type PWM converter 1, a converter transformer 3, an input current detector 8
To 10, input current coordinate converter 14, subtractor 21, reactive current controller 39, adder 41, coordinate inverse converter 28, P
The WM gate controller 29 forms a closed loop of the reactive current, and controls the gate of the voltage-type PWM converter 1 so that the reactive current flows according to the reactive current command value.

Next, control of the output side DC voltage will be described. In order to control the output side DC voltage, first, the input side active current is controlled to a desired value, and as a result, the current flowing into the DC smoothing capacitor 5 is controlled. The output DC voltage, which is a voltage, can also be controlled. here,
As for the control of the input-side active current, the adder 36 is routed through a subtractor 37, an active current controller 38, and an adder 40.
A d-axis voltage command value such that an effective current flows according to the effective current command value from
This is reflected on the actual gate pulse by the gate controller 29. As a result, the effective current flowing due to the generation of the gate pulse is fed back via the voltage-type PWM converter 1, the converter transformer 3, the input current detectors 8 to 10, and the input current coordinate converter 14, and the effective current command is returned again. The value is matched to the value and reflected on the gate pulse.

That is, in FIG. 6, a voltage type PWM converter 1, a converter transformer 3, an input current detector 8
To 10, input current coordinate converter 14, subtractor 37, active current controller 38, adder 40, coordinate inverse converter 28, P
The input-side effective current control closed loop is formed by the WM gate controller 29, and the gate of the voltage-type PWM converter 1 is controlled so that the effective current flows according to the effective current command value.

The output side DC voltage is controlled by the route of the DC voltage command unit 16, the subtractor 19, the DC voltage controller 34, and the adder 36, so that the input side effective voltage becomes the DC voltage according to the DC voltage command value. The current command value is output and reflected by the above-described input-side active current control closed loop. The DC voltage is fed back via the voltage type PWM converter 1, the DC smoothing capacitor 5, and the DC voltage detector 6,
Again, it is compared with the DC voltage command value and is reflected on the input-side effective current command value. That is, in FIG. 6, the voltage type PWM converter 1, the DC smoothing capacitor 5, the DC voltage detector 6, the subtractor 19, the DC voltage controller 34, the adder 3
6 and a closed loop constituted by the above-mentioned input-side active current control closed loop.

[0012]

The conventional control device for the output side DC voltage of the voltage-type PWM converter comprises a series circuit in which the closed loop of the input side active current control is included in the closed loop of the output side DC voltage control as described above. It has a double closed loop structure. In such a case, the response speed of the included input-side active current control closed loop must be set 5 to 10 times faster than the response speed of the output-side DC voltage control closed loop,
Interference between the two closed loops can have a negative effect on transient response and stability. However, in an actual control device, there is a limit to speeding up a response due to a time delay, a noise problem, or the like. Conversely, if the response speed of the input-side active current control closed loop, which is necessary to make the output-side DC voltage control a desired response speed, violates the above-described limit value, the output-side DC voltage control is reversed. There arises a problem that the response speed must be reduced below a desired value.

Further, there is a great contradiction in the control design concept of the conventional series double closed loop control device. That is,
In the design of the output side DC voltage control, it is assumed that the input side active current can be controlled correctly according to the input side active current command value that is the output, while in the design of the input side active current control, the DC voltage is established to some extent. There is an assumption that you do. Therefore, if the DC voltage is zero or a very small value, the input-side effective current cannot be controlled. With the conventional control device, the performance will be as designed as long as the DC voltage is near the command value. However, if the DC voltage deviates from the command value, there is no guarantee that the operation will be good. was there.

The present invention has been made to solve the above problems, and the response speed of the output side DC voltage control is limited by the limit of the response speed of the input side effective current control as in the conventional system. And a control device for a voltage-type PWM converter that can perform input-side effective current control and output-side DC voltage control well and guarantee its performance regardless of the value of the DC voltage. The purpose is to:

[0015]

According to a first aspect of the present invention, there is provided a voltage-type PWM converter control device, comprising: a voltage-type PWM converter connected to a commercial power supply system via a transformer; A DC smoothing capacitor provided on the DC output side; detecting means for detecting the output side DC voltage and DC current and the input side AC voltage and AC current of the voltage type PWM converter; Conversion means for converting the detected values into a rotating coordinate system synchronized with the power supply voltage, DC voltage command means for providing a DC voltage command value of the output DC voltage, and invalidity for providing an invalid current command value of the input AC current Current command means, input-side reactive current control and output-side DC power supply based on the DC voltage command value, the reactive current command value, and each detection value of the detection means. Arithmetic and control means for obtaining a voltage command value for performing control and input-side effective current control; a coordinate inverter for outputting a modulation rate command based on the voltage command value; and a voltage-type PWM converter based on the modulation rate command. In a control device for a voltage-type PWM converter including a PWM gate control means for controlling a gate pulse, the arithmetic control means includes the DC voltage command value, the reactive current command value,
Calculating means for calculating an effective current command value of the input side AC current from the AC voltage detection value via the conversion means and the DC current detection value; and calculating the effective value based on a difference between the DC voltage command value and the DC voltage detection value. A first multiplier for multiplying a current command value, a second multiplier for multiplying a difference between the effective current command value and the effective current detection value via the conversion means by the DC voltage command value, A subtractor for obtaining a difference between a multiplication result of the multiplier and a multiplication result of the second multiplier; a first amplifier for amplifying the subtraction result of the subtractor; A third multiplier for multiplying the difference from the reactive current detection value via the DC voltage command value by the DC voltage command value, and a second amplifier for amplifying the multiplication result of the third multiplier. 2 is given to the above-mentioned coordinate inverse converter to obtain a modulation rate command. The serial PWM gate control means is characterized in controlling the gate pulse of the voltage-type PWM converter.

According to a second aspect of the present invention, there is provided a voltage-type PWM converter control apparatus, wherein the direct-current voltage command value, the reactive current command value, and the conversion means are different from the voltage-type PWM converter control apparatus according to the first aspect. A first compensation value calculator for calculating a DC voltage control feedforward compensation value based on the detected AC voltage value and the detected DC current value, and an addition output obtained by adding the compensation value to the output of the first amplifier And a first adder that gives the coordinate inversion to the above-mentioned coordinate inverse transformer.

Further, a control device for a voltage-type PWM converter according to claim 3 is a voltage-type PWM converter according to claim 1 or 2.
The control device of the WM converter calculates a reactive current control feedforward compensation value based on the DC voltage command value, the reactive current command value, the AC voltage detection value via the conversion means, and the DC current detection value. 2 a compensation value calculator, and a second adder for adding the compensation value to the output of the second amplifier and providing an added output to the coordinate inverse transformer.

[0018]

In the control device for a voltage-type PWM converter according to the first aspect of the present invention, the arithmetic means includes a DC voltage command value, a reactive current command value, an AC voltage detection value via the conversion means, and a DC current detection value. An effective current command value of the input-side AC current is calculated based on the following formula, and a first multiplier multiplies the difference between the DC voltage command value and the DC voltage detection value by the effective current command value, thereby obtaining a second multiplier. Thus, the difference between the effective current command value and the effective current detection value via the conversion means is multiplied by the DC voltage command value, and the subtractor calculates the difference between the multiplication results of the first and second multipliers. The first amplifier amplifies the subtraction result of the subtractor to obtain a DC voltage control output, and the third multiplier calculates a difference between the reactive current command value and the reactive current detection value via the conversion means. Multiply the difference by the above DC voltage command value. , The second amplifier amplifies the multiplication result of the third multiplier to obtain an effective current control output, and supplies the first and second amplifier outputs to the coordinate inverter to obtain a modulation rate command. , The voltage type P by the PWM gate control means
The gate pulse of the WM converter is controlled.

According to a second aspect of the present invention, there is provided a control device for a voltage-type PWM converter.
The first compensation value calculator calculates the DC voltage based on the DC voltage command value, the reactive current command value, the AC voltage detection value via the conversion means, and the DC current detection value for the control device of the M converter. The control feedforward compensation value is calculated, and the first adder adds the compensation value to the output of the first amplifier to perform DC voltage control feedforward compensation.

Further, in the control device for a voltage-type PWM converter according to the third aspect, the control device for the voltage-type PWM converter according to the first or second aspect is configured such that the second compensation value calculator uses the DC voltage command. A reactive current control feedforward compensation value is calculated based on the value, the reactive current command value, the AC voltage detection value via the conversion means, and the DC current detection value, and the second adder calculates the compensation value as a second value. , And feed-forward compensation of reactive current control is performed.

[0021]

【Example】

Embodiment 1 FIG. Hereinafter, a first embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a configuration diagram illustrating a control device for a voltage-type PWM converter according to the first embodiment. In FIG.
Reference numerals 7, 19, 21, 28 and 29 denote the same parts as in the conventional example shown in FIG. 6, and a description thereof will be omitted. As a new code,
Reference numeral 18 denotes a DC current detection value from the DC current detector 7, a d-axis voltage value and a q-axis voltage value from the input voltage coordinate converter 15, a DC voltage command value from the DC voltage commander 16, and a reactive current commander 17. An active current commander that calculates an input-side active current command value based on the reactive current command value of the above; a multiplier 20 that multiplies the calculation result from the subtractor 19 by the active current command value from the active current commander 18; A multiplier 22 multiplies the result of subtraction from the subtractor 21 by a DC voltage command value from the DC voltage commander 16, and a multiplier 23 converts the effective current command value from the effective current commander 18 from the input current coordinate converter 14. A subtractor 24 for subtracting the detected value of the effective current, a multiplier 24 for multiplying the subtraction result of the subtractor 23 by the DC voltage command value from the DC voltage commander 16, and a multiplier 25 for the multiplier 20 based on the multiplication result of the multiplier 24 Multiply the result Jill subtractor, 26 a DC voltage controller which amplifies the subtraction result of the subtracter 25, 27 is a reactive current controller for amplifying the multiplication result of the multiplier 22.

Next, the operation will be described. FIG. 2 shows a model of the main circuit configuration shown in FIG. The operation principle will be described with reference to FIG. First, the symbols shown in FIG. 2 will be described. I _d is input active current, I _q denotes an input-side reactive current, I _i is a DC current value obtained from the output of the DC current detector 7, V _c is the output-side DC voltage, E _d and E _q is the input supply voltage Are the d-axis component and the q-axis component corresponding to the output from the input voltage coordinate converter 15 in FIG. ω is the angular frequency of the input power supply voltage. C is the capacitance value of the DC smoothing capacitor 5, and L and R are mainly the inductance and resistance of the converter transformer 3, but include all the inductance and resistance of the main circuit. Also,
V _d and V _q are the d-axis component and the q-axis component of the voltage generated on the input side of the voltage-type PWM converter 1.

Here, the DC voltage controller 26 shown in FIG.
When the output of which m _d, the output of the reactive current controller 27 and m _q, V _d is the m _d V _c, V _q is proportional to m _q V _c. Here, by taking the unit system appropriately,
V _d = m _d V _c, to be a V _q = m _q V _c.
Now, when I _d , I _q , and V _c are used as state variables and a state equation is set up for FIG. 2, the following equations (1) to (3) are obtained.

[0024]

(Equation 1)

The DC voltage command value of the output DC voltage Vc is V _c0 , and the reactive current command value of the input reactive current _Iq is I _C
q0 ( _Iq0 = 0 when driving at a power factor of 1)
Actually, assuming that the value of the input-side active current I _{d in} the steady state where V _c = V _c0 and I _q = I _q0 holds is I _d0 , the effective current command value I _d0 is given by the following equation (4). Become like Similarly, the value of the output m _d of the DC voltage controller 26 in the stationary state m _d0
Then, _md0 is given by the following equation (5), and the value of the output _mq of the reactive current controller 27 in the steady state is represented by m
_Assuming that _q0 , _mq0 is given by the following equation (6).

[0026]

(Equation 2)

Here, by performing the variable conversion of the following equations (7) and (8), the state equation of the equations (1) to (3) becomes the following equation (9).

[0028]

(Equation 3)

Equation (9) is a state equation of a bilinear system having a product of the state quantity x and the operation quantities u ₁ and u ₂ for this system. It is sufficient that the control law of the manipulated variables u ₁ and u _{2 that} can control this bilinear system stably is determined. For such bi-linear system, it is conceivable to use the control law u _i as the following equation using the appropriate positive definite matrix P. u _i = k _{i ^{[x T (PB i + B i}} T P) x + 2C i T Px ] (10) where the k _i <0. The subscript T represents a transposed matrix.

Next, we look with stability Lyapunov stability theorem of a system that uses the manipulated variable u _i of equation (10). The Lyapunov function V (x) is represented by the following equation. V (x) = x ^T Px (11) The Lyapunov stability theorem states that if there is a P that can always make the time derivative of the Lyapunov function V (x) a negative value at x ≠ 0, stable control is possible. I have. Therefore, (11)
When the time derivative of the equation is calculated using the equations (9) and (10), the following equation (12) is obtained.

[0031]

(Equation 4)

Here, if k _i <0, the second expression on the right side of the above equation
The term is always negative at x ≠ 0. Further, P is calculated by the following equation (1)
Do as in 3).

[0033]

(Equation 5)

[0034] Then, (12) the first term is ^{x T (PA + A T P} ) x = - (2R / L) · (x 1 2 + x 2 2) (14) next to the always negative in x ≠ 0 Become. Therefore, P is (13)
In this case, the time derivative of the Lyapunov function in equation (12) becomes negative at any time when x ≠ 0, and stable control can be performed. Therefore, when the expression (13) is substituted into the expression (10) to specifically determine u ₁ and u ₂ , the following expression is obtained. _{u 1 = (2k 1 / L} ) · (V c0 x 1 -I d0 x 3) (15) u 2 = (2k 2 / L) · V c0 x 2 (16)

Here, k ₁ and k ₂ can be arbitrarily selected (provided that k ₁ <0 and k ₂ <0), so that k ₁ and k ₂ may be appropriately set to realize a desired response speed. (15), (16)
The formula can be rewritten as: u ₁ = G ₁ [V _c0 (I _d0 −I _d ) −I _d0 (V _c0 −V _c )] (17) u ₂ = G ₂ V _c0 (I _q0 −I _q ) (18) where G _{1 = -2k 1 / L> 0,} G 2 = -2k 2 / L>
It becomes 0.

Embodiment 1 shown in FIG. 1 realizes the above equations (17) and (18). In the first embodiment shown in FIG. 1, the effective current command
_d0 is calculated. The DC voltage command unit 16 outputs a DC voltage command value V _c0 , and the reactive current command unit 17 outputs a reactive current command value I _q0 . Further, the DC voltage controller 26 amplifies the gain G ₁ , and the reactive current controller 27 amplifies the gain G ₂ .

That is, as a configuration for executing the equation (17), the DC voltage commander 16, the effective current commander 18,
The subtractor 19, the multiplier 20, the subtractor 23, the multiplier 24, the subtractor 25, and the DC voltage controller 26 constitute one closed loop for simultaneously controlling the output DC voltage and the input effective current, and A d-axis voltage command value is output such that the DC voltage and the effective current are as the voltage command value and the effective current is as the effective current command value, and is reflected on the actual gate pulse by the coordinate inverter 28 and the PWM gate controller 29. Similarly, as a configuration for executing Expression (18), a closed loop that controls the input-side reactive current is configured by the reactive current commander 17, the subtractor 21, the multiplier 22, and the reactive current controller 27. A q-axis voltage command value such that a reactive current according to the reactive current command value flows is output, and is reflected on an actual gate pulse by the coordinate inverse converter 28 and the PWM gate controller 29.

As described above, according to the configuration of the first embodiment shown in FIG. 1, the conventional DC double loop configuration of the output side DC voltage control closed loop and the input side active current control closed loop is eliminated, and the output side DC voltage control closed loop is eliminated. with the arrangements in a closed loop for controlling the input-side reactive current and one closed loop controlled at the same time a DC voltage and an input side active current, the output-side DC voltage V _c and the input-side active current I _d is the DC voltage controller 26 can be controlled simultaneously by a single controller, also be stability is assured it will be understood that it would how the value of the output-side DC voltage V _C is.

Therefore, according to the first embodiment, since one closed loop for simultaneously controlling the output side DC voltage and the input side active current and the closed loop for controlling the input side reactive current are provided, the output side DC voltage and the input Side active current can be controlled simultaneously in one closed loop, and it is not necessary to set the response speed of the input side active current control to high speed as in the past. Therefore, the response speed of the output side DC voltage control is limited. Will not be affected. Further, since control is performed simultaneously by one closed loop, it is not necessary to establish a DC voltage to some extent for controlling the input-side effective current, and control performance can be guaranteed regardless of the DC voltage.

Embodiment 2 FIG. Next, FIG. 3 is a configuration diagram illustrating a control device for a voltage-type PWM converter according to the second embodiment.
3, the same parts as those in the first embodiment shown in FIG. 1 are denoted by the same reference numerals, and the description thereof will be omitted. As a new code, 3
0 is a DC voltage control feedforward compensation value calculator for calculating the value of the output value _md0 of the DC voltage controller 26 in the steady state given by the above equation (5), and 31 is this DC voltage control feedforward compensation value This is an adder for adding the output of the arithmetic unit 30 to the output of the DC voltage controller 26, and the other components are the same as those of the first embodiment shown in FIG.

In the second embodiment shown in FIG. 3, similarly to the first embodiment, the DC voltage commander 16, the effective current commander 18, the subtractor 19, the multiplier 20 , The subtractor 23, the multiplier 24, the subtractor 25, and the DC voltage controller 26 constitute one closed loop for simultaneously controlling the output side DC voltage and the input side active current, and the DC voltage according to the DC voltage command value. The d-axis voltage command value is output so that the effective current becomes the same as the effective current command value, and is reflected on the actual gate pulse by the coordinate inverse converter 28 and the PWM gate controller 29. Similarly, as a configuration for executing Expression (18), a closed loop that controls the input-side reactive current is configured by the reactive current commander 17, the subtractor 21, the multiplier 22, and the reactive current controller 27. hand,
A q-axis voltage command value such that a reactive current according to the reactive current command value flows is output, and is reflected on an actual gate pulse by the coordinate inverse converter 28 and the PWM gate controller 29.

As a result, similar to the first embodiment shown in FIG.
Since it is composed of one closed loop for controlling the output side DC voltage and the input side active current at the same time and one for controlling the input side reactive current, the output side DC voltage and the input side active current can be controlled simultaneously in one closed loop. Therefore, it is not necessary to set the response speed of the input-side active current control at a high speed as in the related art, so that the response speed of the output-side DC voltage control is not restricted. Further, since control is performed simultaneously by one closed loop, it is not necessary to establish a DC voltage to some extent for controlling the input-side effective current, and control performance can be guaranteed regardless of the DC voltage.

On the other hand, the second embodiment is different from the first embodiment shown in FIG.
The following points are different from. Output m _d of the DC voltage controller 26, as can be seen from equation (8), m _d = u ₁ +
m _d0 . However, in the first embodiment shown in FIG. 1 described above, and described a configuration for controlling only the operation amount u _1, no consideration is given to the minute of the output value m _d0 in the steady state. As for the output value m _d0 in the steady state, it can be assumed that the DC voltage controller 26 is configured as, for example, a proportional-integral amplifier, so that it can be covered by the integrated output. In the second embodiment, the output value m _d0 in the steady state _is also calculated to actively perform the feedforward compensation.

That is, in the configuration of the second embodiment shown in FIG. 3, the DC voltage control feedforward compensation value calculator 30 controls the DC voltage command value from the DC voltage commander 16 and the reactive current from the reactive current commander 17. A DC voltage control feedforward compensation value _md0 is calculated based on the command value, the d-axis voltage value and the q-axis voltage value from the input voltage coordinate converter 15, and the DC current detection value by the DC current detector 7, and the calculation is performed. By giving the result of adding the value to the output of the DC voltage controller 26 by the adder 31 to the coordinate inverter 28, the feedforward compensation of the DC voltage control is positively performed so that high-performance control can be obtained. ing.

Therefore, according to the second embodiment, in addition to the effects of the first embodiment, the DC voltage command value, the reactive current command value,
Based on the d-axis voltage value and the q-axis voltage value from the input voltage coordinate converter 15 and the DC current detection value, a feedforward compensation value _md0 for DC voltage control is calculated. Since the result added to the output of the controller 26 is given to the coordinate inverse transformer 28, feedforward compensation of DC voltage control can be performed, and there is an effect that high-performance control is performed.

Embodiment 3 FIG. Next, FIG. 4 is a configuration diagram illustrating a control device for a voltage-type PWM converter according to a third embodiment.
4, the same parts as those in the first embodiment shown in FIG. 1 are denoted by the same reference numerals, and the description thereof is omitted. As a new code, 3
2 is a reactive current control feed-forward compensation value calculator for calculating the output value m _q0 of the reactive current controller 27 in the steady state given by the above-mentioned equation (6), and 33 is this reactive current control feed-forward compensation value This is an adder for adding the output of the arithmetic unit 32 to the output of the reactive current controller 27, and the other components are the same as those of the first embodiment shown in FIG.

In the third embodiment shown in FIG. 4, similarly to the first embodiment, the DC voltage commander 16, the effective current commander 18, the subtractor 19, the multiplier 20 , The subtractor 23, the multiplier 24, the subtractor 25, and the DC voltage controller 26 constitute one closed loop for simultaneously controlling the output side DC voltage and the input side active current, and the DC voltage according to the DC voltage command value. The d-axis voltage command value is output so that the effective current becomes the same as the effective current command value, and is reflected on the actual gate pulse by the coordinate inverse converter 28 and the PWM gate controller 29. Similarly, as a configuration for executing Expression (18), a closed loop that controls the input-side reactive current is configured by the reactive current commander 17, the subtractor 21, the multiplier 22, and the reactive current controller 27. hand,
A q-axis voltage command value such that a reactive current according to the reactive current command value flows is output, and is reflected on an actual gate pulse by the coordinate inverse converter 28 and the PWM gate controller 29.

As a result, similar to the first embodiment shown in FIG.
Since it is composed of one closed loop for controlling the output side DC voltage and the input side active current at the same time and one for controlling the input side reactive current, the output side DC voltage and the input side active current can be controlled simultaneously in one closed loop. Therefore, it is not necessary to set the response speed of the input-side active current control at a high speed as in the related art, so that the response speed of the output-side DC voltage control is not restricted. Further, since control is performed simultaneously by one closed loop, it is not necessary to establish a DC voltage to some extent for controlling the input-side effective current, and control performance can be guaranteed regardless of the DC voltage.

On the other hand, the third embodiment is different from the first embodiment shown in FIG.
The following points are different from. The output m _q of the reactive current controller 27 is m _q = u ₂ + m _{q0 as} can be seen from the equation (8).
It is. However, in the first embodiment shown in FIG. 1 described above, it is set forth the configuration of controlling only the operation amount u _2, no consideration is given minute output value m _q0 in the steady state. Regarding the output value m _q0 in the steady state, it can be assumed that the reactive current controller 27 can be covered by the integrated output by configuring the reactive current controller 27 as, for example, a proportional integration amplifier. In the third embodiment, the output value m _q0 in the steady state is further calculated to actively perform the feedforward compensation.

That is, in the configuration of the third embodiment shown in FIG. 4, the reactive current control feedforward compensation value calculator 32 controls the DC voltage command value from the DC voltage commander 16 and the reactive current from the reactive current commander 17. A reactive current control feedforward compensation value _mq0 is calculated based on the command value, the d-axis voltage value and the q-axis voltage value from the input voltage coordinate converter 15, and the DC current detection value by the DC current detector 7, and the calculation thereof is performed. By giving the result of adding the value to the output of the reactive current controller 27 by the adder 33 to the coordinate inverse transformer 28, feedforward compensation of the reactive current control is positively performed so that high-performance control can be obtained. ing.

Therefore, according to the third embodiment, in addition to the effects of the first embodiment, the DC voltage command value, the reactive current command value,
Based on the d-axis voltage value and the q-axis voltage value from the input voltage coordinate converter 15 and the DC current detection value, a feedforward compensation value m _q0 for the reactive current control is calculated. Since the result added to the output of the controller 27 is given to the coordinate inverse transformer 28, feedforward compensation of reactive current control can be performed, and there is an effect that high-performance control is performed.

Embodiment 4 FIG. Next, FIG. 5 is a configuration diagram illustrating a control device for a voltage-type PWM converter according to a fourth embodiment.
In the configuration shown in FIG. 5, in addition to the configuration of the first embodiment, the output value _md0 of the DC voltage controller 26 in the steady state given by the above-described equation (5) is calculated in the same manner as the second embodiment. DC voltage control feed-forward compensation value calculator 30;
This DC voltage control feedforward compensation value calculator 30
Adder 3 for adding the output of the DC voltage controller 26 to the output of the DC voltage controller 26
(6), which is the same as that of the third embodiment.
The reactive current control feedforward compensation value calculator 32 for calculating the output value _mq0 of the reactive current controller 27 in the steady state given by the equation, and the output of the reactive current control feedforward compensation value calculator 32 are invalidated And an adder 33 for adding to the output of the current controller 27. Others are shown in Figure 1
This is the same as Example 1 shown in FIG.

First, in the fourth embodiment shown in FIG.
Similarly, as a configuration for executing the equation (17), the DC voltage commander 16, the effective current commander 18, the subtractor 19,
The multiplier 20, the subtractor 23, the multiplier 24, the subtractor 25, and the DC voltage controller 26 constitute one closed loop for simultaneously controlling the output DC voltage and the input effective current, and the DC voltage command value is used. A d-axis voltage command value is output so that the DC current and the effective current according to the effective current command value are output, and are reflected on the actual gate pulse by the coordinate inverse converter 28 and the PWM gate controller 29. Similarly,
As a configuration for executing the equation (18), the reactive current command unit 17, the subtracter 21, the multiplier 22, and the reactive current controller 27 constitute a closed loop for controlling the input-side reactive current. A q-axis voltage command value such that a reactive current according to the value flows is output, and the coordinate inverse transformer 28 and the PW
It is reflected on the actual gate pulse by the M gate controller 29.

As a result, similar to the first embodiment shown in FIG.
Since it is composed of one closed loop for controlling the output side DC voltage and the input side active current at the same time and one for controlling the input side reactive current, the output side DC voltage and the input side active current can be controlled simultaneously in one closed loop. Therefore, it is not necessary to set the response speed of the input-side active current control at a high speed as in the related art, so that the response speed of the output-side DC voltage control is not restricted. Further, since control is performed simultaneously by one closed loop, it is not necessary to establish a DC voltage to some extent for controlling the input-side effective current, and control performance can be guaranteed regardless of the DC voltage.

On the other hand, the fourth embodiment is different from the first embodiment shown in FIG.
The following points are different from. Output m _q output m _d and the reactive current controller 27 of the DC voltage controller 26,
As can be seen from equation (8), m _d = u ₁ + m _d0 , m _q =
u ₂ + m _q0 . However, in the first embodiment shown in FIG. 1 described above, the configuration in which only the manipulated variables u ₁ and u ₂ are controlled is described, and the output values m _d0 and m _{q0 in} the steady state are not considered. Output values m _d0 and m _q0 in the steady state
In the case of (1), it is possible to assume that the DC voltage controller 26 and the reactive current controller 27 are each configured as, for example, a proportional-integral amplifier, so that the integrated output can be covered. In _{No. 3} , both the output values m _d0 and m _{q0 in} the steady state are calculated, and the feedforward compensation is actively performed.

That is, in the configuration of the fourth embodiment shown in FIG. 5, the DC voltage control feedforward compensation value calculator 30 and the reactive current control feedforward compensation value calculator 32 respectively control the DC voltage from the DC voltage commander 16. Command value, the reactive current command value from the reactive current command device 17,
Based on the d-axis voltage value and the q-axis voltage value from the input voltage coordinate converter 15 and the DC current detection value by the DC current detector 7, the DC voltage control feedforward compensation value m _d0 and the reactive current control feedforward compensation value m _q0 is calculated, and the calculated value is added to the output of the DC voltage controller 26 and the output of the reactive current controller 27 by the adders 31 and 33, respectively. In addition, feedforward compensation of reactive current control is performed so that high-performance control can be obtained.

Therefore, according to the fourth embodiment, the first embodiment
In addition to the effects of the above, the DC voltage control feedforward compensation value calculator 30 and the reactive current control feedforward compensation value calculator 32 provide a DC voltage command value, a reactive current command value, and a d-axis voltage from the input voltage coordinate converter 15, respectively. Calculate feedforward compensation values _md0 and _mq0 for DC voltage control and reactive current control based on the DC voltage control value and the reactive current control value based on the DC voltage control value and the DC current detection value, and add the calculated values to the DC voltage controller by adders 31 and 33. 26 and the output of the reactive current controller 27 are added to the coordinate inverse transformer 28, so that feedforward compensation of DC voltage control and reactive current control can be performed, and high-performance control can be performed. This has the effect of being done.

[0058]

As described above, according to the first aspect of the present invention, the DC double loop configuration of the conventional closed loop of the DC voltage control on the output side and the closed loop of the effective current control on the input side is eliminated, and the output side is controlled. One closed loop is configured to simultaneously control the DC voltage and the input-side active current, and the output-side DC voltage and the input-side active current of the voltage-type PWM converter are simultaneously controlled by one controller. In addition, the response speed of the output side DC voltage control due to the response speed limit of the input side effective current control can be set to a desired value without being restricted.
In addition, there is an effect that stable control can be performed at any value of the DC voltage.

According to a second aspect of the present invention, in accordance with the first aspect, a DC voltage control feed is performed based on a DC voltage command value, a reactive current command value, an AC voltage detection value via a converter, and a DC current detection value. Since the compensation value of the first compensation value calculator for calculating the forward compensation value is added to the DC voltage controller by the adder, feedforward compensation of DC voltage control can be performed, and high-performance control can be performed. Is achieved.

Further, according to the third aspect, the reactive current based on the DC voltage command value, the reactive current command value, the AC voltage detected value via the converting means, and the DC current detected value, Since the compensation value by the second compensation value calculator for calculating the control feedforward compensation value is added to the reactive current controller by the adder, the feedforward compensation of the reactive current control can be performed, and high performance can be achieved. This has the effect of performing appropriate control.

[Brief description of the drawings]

FIG. 1 is a configuration diagram showing a control device for a voltage-type PWM converter according to Embodiment 1 of the present invention.

FIG. 2 is a model diagram for explaining the operation principle of the present invention.

FIG. 3 is a configuration diagram illustrating a control device for a voltage-type PWM converter according to a second embodiment of the present invention.

FIG. 4 is a configuration diagram showing a control device for a voltage-type PWM converter according to Embodiment 3 of the present invention.

FIG. 5 is a configuration diagram illustrating a control device for a voltage-type PWM converter according to Embodiment 4 of the present invention.

FIG. 6 is a configuration diagram illustrating a conventional control device for a voltage-type PWM converter.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Voltage-type PWM converter 3 Transformer for converter 5 DC smoothing capacitor 6 DC voltage detector 7 DC voltage detector 8 AC current detector 9 AC current detector 10 AC current detector 11 AC current detector 12 AC current detector 13 AC current detector 14 Input current coordinate converter 15 Input current coordinate converter 16 DC voltage commander 17 Reactive current commander 18 Effective current commander 19 Subtractor 20 Multiplier 21 Subtractor 22 Multiplier 23 Subtractor 24 Multiplier 25 Subtractor 26 DC voltage controller (amplifier) 27 Reactive current controller (amplifier) 28 Coordinate inverter (amplifier) 29 PWM gate controller 30 DC voltage control feedforward compensation value calculator 31 Adder 32 Reactive current control feedforward Compensation value calculator 33 Adder

Claims (3)

(57) [Claims] 1. A voltage type PWM converter connected to a commercial power supply system via a transformer, a DC smoothing capacitor provided on a DC output side of the voltage type PWM converter,
Detecting means for detecting an output side DC voltage and a DC current and an input side AC voltage and an AC current of the voltage type PWM converter; and a rotating coordinate system in which the detected values of the input side AC voltage and the AC current are respectively synchronized with a power supply voltage. Converting means, DC voltage command means for providing a DC voltage command value of the output DC voltage, reactive current command means for providing a reactive current command value of the input AC current, the DC voltage command value and the An arithmetic control unit for obtaining a voltage command value for performing input-side reactive current control, output-side DC voltage control, and input-side active current control based on the reactive current command value and each detection value obtained by the detection unit; and A coordinate inverse converter that outputs a modulation rate command, and the voltage type P based on the modulation rate command.
In a control device for a voltage-type PWM converter comprising: a PWM gate control unit for controlling a gate pulse of a WM converter, the DC voltage command value, the reactive current command value, and the AC Calculating means for calculating an effective current command value of the input side AC current from the voltage detection value and the DC current detection value; and a first means for multiplying a difference between the DC voltage command value and the DC voltage detection value by the effective current command value. A second multiplier for multiplying a difference between the effective current command value and the effective current detection value via the conversion means by the DC voltage command value, and a multiplication result of the first multiplier and the second multiplier. A subtractor for obtaining a difference between the result of the multiplication by the second multiplier and a first amplifier for amplifying the result of the subtraction by the subtractor; a reactive current command value and a reactive current detection value via the conversion means; And a second amplifier for amplifying the result of the multiplication of the third multiplier by multiplying the difference between the first and second DC voltage command values by the DC voltage command value. The modulation ratio command is given to the converter to obtain the P
A voltage type PWM, wherein a gate pulse of the voltage type PWM converter is controlled by WM gate control means.
Control device for M converter. 2. A first compensation for calculating a DC voltage control feedforward compensation value based on the DC voltage command value, the reactive current command value, the AC voltage detection value via the conversion means, and the DC current detection value. 2. The voltage source according to claim 1, further comprising a value calculator, and a first adder for providing an added output obtained by adding the compensation value to the output of the first amplifier to the coordinate inverse transformer. Control device for PWM converter. 3. A second compensation for calculating a reactive current control feedforward compensation value based on the DC voltage command value, the reactive current command value, the AC voltage detected value via the conversion means, and the DC current detected value. 3. The apparatus according to claim 1, further comprising a value calculator, and a second adder for providing an added output obtained by adding the compensation value to the output of the second amplifier to the coordinate inverse transformer. Control device for voltage source PWM converter.