JP2014230318A - Power conditioner - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a power conditioner capable of arbitrarily setting a power factor as a conventional product specification.SOLUTION: The power conditioner comprises an inverter control circuit 17 for controlling an inverter circuit 13, and input means 11 to which a power factor input value is inputted. The inverter control circuit 17 includes: effective current command value calculation means 17b for calculating an effective current command value Iq* from a DC voltage of DC power; ineffective current command value calculation means 17c for calculating an ineffective current command value Id* from the effective current command value Iq* and an advanced-phase angle command value θ*; and control signal generation means 17k which generates a signal for controlling the inverter circuit 13 on the basis of the effective current command value Iq* and the ineffective current command value Id*. For the advanced-phase angle command value θ*, in the case where the power factor input value is less than 1, the power factor in rating output of the power conditioner is a value which is not less than a power factor input value λbut is substantially matched thereto.

Description

  The present invention relates to a power conditioner including an inverter circuit that outputs AC power that can be linked to a power system.

  Conventionally, there is one that adjusts a pulse width modulation signal of a three-phase inverter so that AC power output from a power conditioner has a desired power factor (Patent Document 1). In the power factor adjustment described in Patent Document 1, the desired power factor is 1, and phase correction is executed in order to maintain power factor = 1. This is to reduce reactive power to zero in order to reduce wasteful power consumption.

  On the other hand, a grid-connected power conditioner is required to have a function of suppressing an increase in system voltage, and in order to respond to this, there is a method of increasing reactive power by advance angle control that advances the phase of current. In particular, large-scale facilities increase in photovoltaic power generation, and in a power conditioner used in such facilities, a function of suppressing an increase in system voltage is important. Therefore, in order to increase the reactive power for the advance angle control, there are some which reduce the power factor in the specifications of the power conditioner product.

  Here, the specification of the power conditioner product describes a power factor lower limit value at the rated output, that is, a guaranteed power factor, such as “power factor 0.95 or more (at rated output)”.

JP 2013-38844 A

  However, with this power conditioner product with a power factor of 0.95 or higher (at rated output), even if the administrator wants that the power factor does not fall below 0.98, for example, in order to reduce reactive power, this is guaranteed. Not. On the other hand, even if the administrator desires the setting of power factor = 0.80 because of the function of suppressing the increase of the system voltage, it cannot cope with it.

  Accordingly, an object of the present invention is to provide a power conditioner in which a power factor as a conventional product specification can be arbitrarily set.

  In order to achieve the above object, a power conditioner according to one configuration of the present invention is a power conditioner that outputs AC power that can be connected to an electric power system, and an inverter circuit that converts DC power into AC power; An inverter control circuit for controlling the inverter circuit, the active current command value calculating means for calculating an effective current command value from the DC voltage of the DC power, and the active current command calculated by the effective current command value calculating means The reactive current command value calculating means for calculating the reactive current command value from the value and the advance angle command value, and the control command value based on the active current command value and the reactive current command value, respectively, from the inverter An inverter control circuit having a control signal generating means for generating a signal for controlling the circuit, and an input means for inputting a power factor input value; The notation phase angle command value is such that when the power factor input value is less than the predetermined power factor value, the power factor at the rated output of the power conditioner does not fall below the power factor input value. Value.

  According to this configuration, since the power factor input value can be input from the input unit, the administrator can set an appropriate power factor according to the power system to which the power conditioner is linked. The phase advance command value used in the inverter control circuit is such that when the power factor input value is less than the predetermined power factor value, the power factor at the rated output of the power conditioner does not fall below the power factor input value. Since the values are almost the same, if the power factor input value is less than the predetermined power factor value, the power conditioner maintains a power factor equal to or higher than the power factor input value.

  In a preferred embodiment, the predetermined power factor value is a maximum output power factor of the inverter, and the advance angle command value is determined when the power factor input value is equal to or greater than the predetermined power factor value. The power factor at the rated output of the power conditioner is such that the power factor input value matches the predetermined power factor value. That is, when the power factor input value exceeds the maximum output power factor that is the upper limit of the performance of the power conditioner, such as 1 or a value slightly smaller than 1, the power conditioner at the rated output The power factor is the maximum output power factor.

  In a preferred embodiment, a correspondence relationship storage unit that stores a correspondence relationship between a power factor input value and a phase advance angle command value is provided, and the phase advance angle command value used by the reactive current command value calculation unit is the correspondence relationship. Based on the correspondence stored in the storage unit, the advance angle command value corresponding to the power factor input value input from the input means is set. According to this, since the correspondence storage unit stores the correspondence between the power factor input value and the advance angle command value, a complicated calculation process or the like is unnecessary. That is, the power factor at the rated output of the power conditioner is a value that is a value that substantially matches the power factor input value when the power factor input value is less than the predetermined power factor value. The angle command value can be easily obtained from the stored correspondence. Here, the “advance angle command value” is preferably a value before adjustment. That is, since the inverter is retarded by an inverter circuit or the like, the retarded phase is adjusted together with the advance angle command value acquired from the correspondence storage unit.

  In a preferred embodiment, the reactive current command value is obtained by multiplying the active current command value by a tangent of the advance angle command value. According to this, when the output power of the inverter is smaller than the rated output, the active current command value also becomes smaller. Therefore, the reactive current obtained by multiplying the effective current command value by the tangent of the advance angle command value is obtained. The command value also becomes smaller. For this reason, the power factor of the inverter is increased. Therefore, even if the output power of the power conditioner is smaller than the rated output and there is no phase advance control, that is, the output power when the power factor input value is 1, and the power factor is reduced, The power factor does not fall below the power factor input value. Thus, for example, it is ensured that the power factor does not fall below the power factor input value when the output power of the power conditioner ranges from a predetermined ratio (for example, 12.5%) of the rated output to the rated output.

  In a further preferred embodiment, the inverter circuit is a three-phase inverter circuit, and the control command value includes an effective voltage command value and a reactive voltage command value, and the AC power output from the power conditioner. Phase voltage detection means for detecting the phase voltage of the AC power, and phase current detection means for detecting the phase current of the AC power output from the power conditioner, the inverter control circuit further comprising the effective current command value The effective voltage command value calculating means for calculating the effective voltage command value from the reactive voltage command value calculating means for calculating the reactive voltage command value from the reactive current command value, the effective voltage command value calculating means, The reactive voltage command value calculation means detects the effective current command value and the reactive current command value, respectively, by the phase current detection means. The effective voltage command value and the reactive voltage command value are respectively calculated by compensating with the voltage detected by the AC voltage detecting means after being converted into a voltage value after being compensated by the phase current, and the control signal generating means A PWM signal for controlling the inverter circuit is generated based on the effective voltage command value and the duty ratio calculated from the reactive voltage command value calculated by the voltage command value calculating unit and the reactive voltage command value calculating unit, respectively. .

  According to this, since the PWM signal for controlling the inverter circuit is generated using the advance angle command value corresponding to the power factor input value, the power factor of the output power of the power conditioner is set to the advance angle command value. Can be adjusted based on.

  According to the power conditioner according to the present invention, the power factor as the conventional product specification can be arbitrarily set.

1 is a schematic block diagram of a system including a power conditioner according to an embodiment of the present invention. It is a schematic block diagram of the inverter control circuit of the power conditioner of FIG. It is a figure of the correspondence of the correspondence memory | storage part of the power conditioner of FIG. (A)-(d) is a graph which shows the example of the measurement power factor with respect to the output in the power conditioner of FIG. 1, Comprising: Power factor input value is 1.00, 0.98.0.95, and 0, respectively. .92 in the case of .92.

Hereinafter, a power conditioner according to an embodiment of the present invention will be described with reference to the drawings.
A power conditioner 1 according to the present embodiment shown in FIG. 1 is connected to a DC power source 2, converts DC power output from the DC power source 2 into AC power, and connects the AC power to the AC power system 3. To go. The DC power source 2 is a solar cell or a fuel cell, for example.

  The power conditioner 1 includes a power factor input unit 11, a DC voltage detection unit 12, an inverter circuit 13, a filter circuit 14, a line voltage detection unit 15, a phase current detection unit 16, an inverter control circuit 17, and a correspondence relationship storage unit 18. Prepare.

The power factor input unit 11 includes a dial, a button, and the like, and receives an _{input by} the administrator of the power factor input value λ _input . The manager is a person who is responsible for the installation and management of the inverter 1. The power factor input value λ _input can be _input with, for example, two digits after the decimal point, and a value such as a power factor of 0.95 is input by the administrator with a dial or a button.

The power conditioner 1 according to the present embodiment has a variable power factor as its specification, and when the power factor input value λ _input input from the power factor input means 11 is less than the maximum output power factor value, A power factor equal to or higher than the power factor input value λ _input is maintained in a range from a predetermined ratio (for example, 12.5%) of the rated output to the rated output. In particular, the power conditioner 1, the power factor at the rated output, the power factor substantially matches the input value lambda _{input The,} and performs control so that the power factor input value lambda _{input The} above values.

As an example, if the power factor input value λ _input = 0.90, the performance of the inverter will be “power factor 0.90 or more (12.5% of rated output to rated output)”. When λ _input = 0.95, the performance of the power conditioner is “power factor 0.95 or more (12.5% of rated output to rated output)”. However, when the power factor input value λ _input = 1, the power factor of the output power of the power conditioner is smaller than 1 but very close to 1, or the maximum output power factor of the power conditioner or A slightly smaller value. That is, when the power factor input value λ _input is equal to or greater than the maximum output power factor, the power factor at the rated output of the power conditioner substantially matches the maximum output power factor.

When there is no input from the power factor input means 11, it is considered that the power factor input value λ _input = 1. The input from the power factor input means 11 is also accepted at any time while the power conditioner 1 is activated.

  The DC voltage detection means 12 detects the DC voltage Vdc input to the inverter circuit 13. The input DC voltage Vdc is a DC voltage of a DC output from the DC power supply 2 or a DC voltage obtained by boosting this DC voltage by a booster circuit (not shown). The inverter circuit 13 converts the input DC voltage Vdc into an AC voltage. The inverter circuit 13 in this embodiment is a three-phase inverter circuit, and includes a total of six or more switching elements (not shown) made up of three pairs, and these elements are controlled by a PWM signal described later. The The filter circuit 14 includes a reactor (not shown) and a capacitor (not shown), and outputs a three-phase AC voltage in combination with the inverter circuit 13.

  The line voltage detection means 15 detects the line voltage of the AC power output from the filter circuit 14, and this line voltage is input to the inverter control circuit 17. It becomes possible to calculate the phase voltages Vu, Vv, Vw of the three phases from these line voltages. The phase current detection means 16 detects two-phase phase currents among the three-phase phase currents Iu, Iv, Iw in the filter circuit 14, and these two-phase phase currents are input to the inverter control circuit 17. From these two-phase currents, the phase currents Iu, Iv, Iw of the three phases can be calculated. The phase current detection means 16 may detect not a two-phase phase current but a three-phase phase current.

  The inverter control circuit 17 is configured by a microcomputer, for example. As shown in FIG. 2, the inverter control circuit 17 includes a phase advance angle adjusting unit 17a, a first adder / subtractor 17b, an active current command value calculating unit 17c, a reactive current command value calculating unit 17d, a phase voltage calculating unit 17e, 1 coordinate converter 17f, phase current calculator 17g, second coordinate converter 17h, second adder / subtractor 17i, third adder / subtractor 17j, effective voltage command value calculator 17k, fourth adder / subtractor 17l, The reactive voltage command value calculator 17m, the fifth adder / subtractor 17n, the inverse coordinate converter 17o, the duty ratio calculator 17p, and the PWM signal generator 17q are provided.

The advance angle adjustment unit 17a calculates the advance angle command value θ * according to the input advance angle θ _input (advanced advance angle command value) with the advance angle adjustment value θ _adj stored in the memory. To do. This is achieved by adjusting the slow phase generated by the inverter circuit 13 and the filter circuit 14 in FIG. 1 so that the power conditioner 1 in the case where there is no phase advance control from the outside, that is, there is no input from the power factor input means 11. This is because the power factor of the output power is brought close to 1 so that the maximum output power factor of the power conditioner 1 is obtained.

The advance angle adjustment value θ _adj is automatically acquired at the time when the input from the power factor input means 11 is not yet performed after the activation of the power conditioner 1. For example, the phase difference between the AC voltage and AC current output from the filter circuit 14 may be detected by a phase difference detection unit (not shown), and the phase difference may be used as the advance angle adjustment value θ _adj . This phase difference may be obtained, for example, from the difference between any one of the three phases U, V, and W and the zero cross point of the AC current.

  The first adder / subtractor 17b in FIG. 2 subtracts the DC voltage control reference value Vdc_ref from the DC voltage Vdc detected by the DC voltage detector 12 (FIG. 1). The effective current command value calculation unit 17c is composed of, for example, a PI controller, and calculates the effective current command value Iq * from the difference between the DC voltage Vdc and the reference voltage Vdc_ref. The reactive current command value calculation unit 17d includes a multiplier, and calculates the reactive current command value Id * by multiplying the active current command value Iq * by the tangent tan θ * of the advance angle command value θ *. Thus, the advance angle command value θ * is a command value for controlling the reactive power component in the output power of the power conditioner 1 (FIG. 1).

  The phase voltage calculation unit 17e calculates the phase voltages Vu, Vv, and Vw from the line voltage detected by the line voltage detection unit 15 (FIG. 1). The first coordinate conversion unit 17f converts the phase voltages Vu, Vv, Vw calculated by the phase voltage calculation unit 17e into an effective voltage compensation value Vq and a reactive voltage compensation value Vd on the dq rotation coordinate axis. The phase current calculation unit 17g calculates the phase currents Iu, Iv, and Iw of the three phases from the two-phase phase currents detected by the phase current detection unit 16 (FIG. 1). The second coordinate conversion unit 18h converts the phase currents Iu, Iv, Iw calculated by the phase current calculation unit 18g into an effective current compensation value Iq and a reactive current compensation value Id on the dq rotation coordinate axis. The line voltage detector 15 (FIG. 1) and the phase voltage calculator 17e constitute a phase voltage detector, and the phase current detector 16 (FIG. 1) and the phase current calculator 17g constitute a phase current detector. The

  The second adder / subtractor 17i calculates the difference ΔIq by compensating the effective current command value Iq * with the effective current compensation value Iq. The third adder / subtractor 17j calculates the difference ΔId by compensating the reactive current command value Id * with the reactive current compensation value Id. The effective voltage command value calculation unit 17k includes, for example, a PI controller, and calculates an effective voltage command value Vq * from the effective current difference ΔIq. The fourth adder / subtractor 17l compensates the effective voltage command value Vq * with the voltage compensation value Vq, and calculates the compensated effective voltage command value Vqo *. The reactive voltage command value calculation unit 17m includes, for example, a PI controller 17i, and calculates the reactive voltage command value Vd * from the reactive current difference ΔId. The fifth adder / subtractor 17n calculates the post-compensation reactive voltage command value Vdo * by compensating the reactive voltage command value Vd * with the voltage compensation value Vd.

  The inverse coordinate conversion unit 17o converts the compensated effective voltage command value Vqo * and the compensated invalid voltage command value Vdo * on the rotation coordinate axis into voltage command values Vu *, Vv *, and Vw * on the UVW coordinate axis. Then, the duty ratio calculation unit 17p calculates each duty ratio from these voltage command values Vu *, Vv *, Vw *. Next, the PWM signal generation means 17q generates a PWM signal having a pulse width corresponding to these duty ratios. These PWM signals control a switching element (not shown) of the inverter circuit 13 (FIG. 1).

Next, the input phase advance angle θ _input and the phase advance angle command value θ * will be described. First, the input advance angle θ _input corresponding to the advance angle command value θ * before adjustment is obtained from the correspondence storage unit 18 shown in FIG. The correspondence relationship storage unit 18 is constructed on a memory of a microcomputer in which the inverter control circuit 17 is configured, for example. As shown in FIG. 3, the correspondence relationship storage unit 18 stores the correspondence relationship between the power factor input value λ _input and the input advance angle θ _input . Here, the phase advance angle corresponding to the power factor input value λ _input is a relational expression of λ _input = cos θ _input (that is, θ _input = cos ⁻¹ λ _input ) if there is no current compensation or voltage compensation in the inverter control circuit 17. It is requested from. However, in the present embodiment, since there is current compensation and voltage compensation in the inverter control circuit 17, the input advance angle θ _input does not coincide with cos ⁻¹ λ _input . In the present embodiment, the relationship storage unit 18 defines the relationship between the power factor input value λ _input and the input advance angle θ _input, and the input advance angle θ _input is acquired by referring to this relationship. The The relationship between the power factor input value lambda _{input The} the input phase advance angle theta _{input The,} if from the power factor input value lambda _{input The} the derivable accurately input the phase advance angle theta _{input The,} limited to using the stored corresponding relationship Instead, they may be associated by any means.

The phase advance angle θ _input acquired in this way is adjusted by the phase advance angle adjustment value θ _adj in the phase advance angle adjustment unit 17a of FIG. 2 to calculate the phase advance angle command value θ *. That is, the calculation of θ * = θ _input + θ _adj is executed. Then, the tangent tan θ * of the advance angle command value θ * is calculated. That is, in the advance angle adjustment unit 17a, calculation of tan θ * = tan (θ _input + θ _adj ) is executed.

Here, in the present embodiment, the relationship between the power factor input value λ _input and the input advance angle θ _input is stored in the correspondence storage unit 18 because the power factor input value λ _input and the input advance angle θ _This is because the relationship between _input and function is complicated. When expressed as a function, compensation is made from the reactive current command value Id * (= Iq * × tan θ *) using the tangent tan θ * of the phase advance command value θ * calculated by adjusting the _input phase advance angle θ _input. When the post-reactive voltage command value Vdo * is calculated, the current compensation value Id is subtracted and the voltage compensation value Vd is added. Therefore, the post-compensation reactive voltage command value Vdo * is proportional to the reactive current command value Id *. This corresponds to the sum of the term and the term depending on the current compensation value Id and the voltage compensation value Vd. The relational expression (1) is shown below.

Vdo * = A × Id * + f (Id, Vd)
= A × (Iq * × tan θ *) + f (Id, Vd) (1)
Here, A is a constant, and f (Id, Vd) is a variable depending on the current compensation value Id and the voltage compensation value Vd.

Here, since the reactive power component Q in the output power of the power conditioner 1 (FIG. 1) is proportional to the post-compensation reactive voltage command value Vdo *, the following relational expression (2) is established.
Q = B × Vdo *
= B × A × (Iq * × tan θ *) + B × f (Id, Vd) (2)
However, B shows a constant.

On the other hand, the reactive power component Q in the output power of the power conditioner 1 (FIG. 1) is ideally expressed by the following formula (3), where P is the active power component in the output power of the power conditioner 1.
Q = P × tan (cos ⁻¹ λ _input ) (3)
This expression (3) indicates that the power factor of the output power of the power conditioner 1 (FIG. 1) matches the power factor input value λ _input input from the power factor input means 11 (FIG. 1). .

The formula (2) and from (3), the relationship between the power factor input value lambda _{input The} and phase advance angle command value theta *, since it depends on the variable f (Id, Vd), the power factor input value lambda _{input The} proceeds When expressed as a function of the phase angle command value θ *, it becomes complicated. On the other hand, in the present embodiment, the correspondence relationship storage unit 18 stores the correspondence relationship between the power factor input value λ _input and the input advance angle θ _input corresponding to the unadjusted advance angle command value θ *. Therefore, it is possible to easily obtain an appropriate advance angle command value θ *.

The correspondence relationship storage unit 18 in FIG. 3 stores all power factor input values λ _input that can be input from the power factor input unit 11 (FIG. 1). Therefore, when the power factor input value λ _input is input from the power factor input means 11 (FIG. 1), the input advance angle θ _input (and hence the advance angle command value θ *) is uniquely determined from this correspondence. . Note that a minimum value may be provided for the power factor input value λ _input , for example, 0.80 may be set as the minimum power factor input value. In this case, the correspondence storage unit 18 stores power factor input values λ of 1.00, 0.99, 0.98, 0.97, 0.96, 0.95, 0.94,. _{The input} and the input advance angle θ _input corresponding to each of them are stored.

The correspondence relationship stored in the correspondence relationship storage unit 18 is unique to the product of the power conditioner 1. Thus, before shipment of the product, and the power factor at the output power of the input phase advance angle theta _{input The} a power conditioner 1 for a single power conditioner 1 is measured, and the input phase advance angle theta _{input The} power factor Is stored in the corresponding relationship storage unit 18 of all the same products as the corresponding relationship between the power factor input value λ _input and the input advance angle θ _input .

Next, the power factor other than at the rated output will be considered.
The output power of the power conditioner 1 in FIG. 1 decreases and becomes smaller than the rated output when the effective current command value Iq * in FIG. 2 decreases. The reactive power component Q in the above formula (2) has a smaller first term (B × A × (Iq * × tan θ *)) component than the second term (B × f (Id, Vd)) component. . Therefore, the ratio at which the advance angle command value tan θ * affects the reactive power component Q decreases, and the ratio at which the compensation component f (Id, Vd) of the second term affects increases.

Thus, for example, when the output power of the power conditioner 1 (FIG. 1) is considerably smaller than the rated output, the above equation (2) is approximated as the following equation (4).
Q≈B × f (Id, Vd) (4)

On the other hand, the above expression (2) is obtained even if the first term (B × A × (Iq * × tan θ *)) is not smaller than the second term (B × f (Id, Vd)), that is, the output Even if the electric power is as large as the rated output, when tan θ * = 0 (that is, when the power factor input value λ _input is close to 1), Q = B × f (Id, Vd). That is, the above equation (2) is Q = B × f (Id, Vd) if tan θ * = 0 even if the output power of the power conditioner 1 (FIG. 1) is the rated output.

  From these, as the output power of the power conditioner 1 (FIG. 1) becomes smaller, the reactive power component of the output power becomes the advance angle command when the output power of the power conditioner 1 (FIG. 1) is at the rated output. It can be said that it approaches the reactive power component when the value θ * is zero.

Accordingly, since the power factor when the advance angle command value θ * is zero and there is almost no reactive power component is 1, the power factor of the power conditioner 1 is lower than the rated output. The power factor approaches the power factor value (maximum output power factor), and this ensures that the power factor is always greater than the power factor input value λ _input . However, this is not the case when the output power is zero. Thus, since the power factor equal to or greater than the power factor input value λ _input inputted from the power factor input means 11 (FIG. 1) is maintained, the power conditioner 1 (FIG. 1) according to the present embodiment has a rated output. In the range from a predetermined ratio (for example, 12.5%) to the rated output, the power factor of the output power of the power conditioner 1 (FIG. 1) is equal to or greater than the power factor input value λ _input .

4A to 4D, the power conditioner 1 in the case of the power factor input value λ _input = 1.00, 0.98, 0.95 and 0.92 of the power conditioner 1 of the present embodiment is shown. The measured power factor for the output of. The rated output of the power conditioner 1 is 10 kW. According to these measurements, with the exception of the power factor input value lambda _{input The} = 1.00 of FIG. 4 (a), as shown in FIG. 4 (b) ~ (d) , the power factor input value lambda _{input The} = 0.98, 0.95 and 0.92, respectively, "Power factor 0.98 or more (12.5% of rated output to rated output)", "Power factor 0.95 or more (rated output) 12.5% to rated output) ”and“ power factor of 0.92 or more (12.5% of rated output to rated output) ”are satisfied.

4B to 4D, when the _input power value λ _{input is} 0.98, 0.95, and 0.92, the measured power factor increases as the output power decreases. The power factor of 4 (a) approaches the measured power factor at the same output power when λ _input = 1.00. As a result, as the output power of the power conditioner 1 (FIG. 1) becomes smaller, the reactive power out of the output power is advanced when the output power of the power conditioner 1 (FIG. 1) is at the rated output. It is shown that the reactive power approaches the reactive power when the angle command value tan θ * is zero.

  As mentioned above, according to the power conditioner of this invention, the power factor as a specification of a power conditioner product is variable.

  In the above embodiment, the inverter control circuit of FIG. 2 can calculate the reactive current command value from the active current command value and the advance angle command value, and the reactive power command value is used to output power of the power conditioner. Any circuit may be used as long as the rate can be controlled.

DESCRIPTION OF SYMBOLS 1 Power conditioner 3 Electric power system 11 Input means 13 Inverter circuit 17 Inverter control circuit 17b Active current command value calculating means 17c Invalid current command value calculating means 17k Control signal generating means Iq * Effective current command value Id * Invalid current command value Vq * Effective voltage command value Vd * Invalid voltage command value θ * Lead angle command value λ _input Power factor input value

Claims (5)

A power conditioner that outputs AC power that can be connected to the power system,
An inverter circuit for converting DC power into AC power;
An inverter control circuit for controlling the inverter circuit,
Active current command value calculating means for calculating an effective current command value from a DC voltage of the DC power;
Reactive current command value calculating means for calculating a reactive current command value from the active current command value calculated by the effective current command value calculating means and the advance angle command value, and
An inverter control circuit having control signal generation means for generating a signal for controlling the inverter circuit from a control command value based on the active current command value and the reactive current command value,
An input means for inputting a power factor input value,
When the power factor input value is less than the predetermined power factor value, the phase advance angle command value is such that the power factor at the rated output of the power conditioner is substantially the same without falling below the power factor input value. Power conditioner that is a good value. In the power conditioner of Claim 1,
The predetermined power factor value is the maximum output power factor of the inverter.
When the power factor input value is equal to or greater than the predetermined power factor value, the advance angle command value is such that the power factor at the rated output of the power conditioner is the power factor input value equal to the predetermined power factor value. The inverter is a value that matches. The power conditioner according to claim 1 or 2, further comprising:
A correspondence storage unit for storing the correspondence between the power factor input value and the advance angle command value;
The advance angle command value used by the reactive current command value calculation means is an advance angle corresponding to the power factor input value input from the input means, based on the correspondence stored in the correspondence storage unit. The inverter is set to the command value. In the power conditioner as described in any one of Claim 1 to 3,
The reactive current command value is a power conditioner obtained by multiplying the active current command value by a tangent of the advance angle command value. In the power conditioner as described in any one of Claim 1 to 4,
The inverter circuit is a three-phase inverter circuit;
The control command value includes an effective voltage command value and an invalid voltage command value,
further,
Phase voltage detection means for detecting a phase voltage of the AC power output from the power conditioner;
Phase current detection means for detecting a phase current of the AC power output from the power conditioner,
The inverter control circuit further includes:
Effective voltage command value calculating means for calculating the effective voltage command value from the effective current command value; and
Reactive voltage command value calculating means for calculating the reactive voltage command value from the reactive current command value,
The effective voltage command value calculating means and the reactive voltage command value calculating means compensate the effective current command value and the reactive current command value with the phase current detected by the phase current detecting means, respectively, and convert them into voltage values. Compensating with the phase voltage detected by the phase voltage detection means, calculating the effective voltage command value and the reactive voltage command value,
The control signal generating unit is configured to generate the inverter based on the duty ratio calculated from the effective voltage command value and the reactive voltage command value calculated by the effective voltage command value calculating unit and the reactive voltage command value calculating unit, respectively. A power conditioner that generates a PWM signal to control the circuit.

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