WO2014034003A1

WO2014034003A1 - Control device for rectifier circuit device and rectifier circuit device

Info

Publication number: WO2014034003A1
Application number: PCT/JP2013/004091
Authority: WO
Inventors: 吉田　泉; 京極　章弘; 吉朗土山; 川崎　智広; シンホイ戴
Original assignee: パナソニック株式会社
Priority date: 2012-08-30
Filing date: 2013-07-02
Publication date: 2014-03-06
Also published as: JPWO2014034003A1; CN104604113B; CN104604113A; JP6145896B2

Abstract

The rectifier circuit device of the present invention comprises a control device that is configured to: control the chopping of a semiconductor switch (104) so that the waveform of a detected current becomes a target current waveform; control the amplitude of the target current waveform so that a detected DC voltage becomes a predetermined target DC voltage; and to control the target DC voltage so that either a chopping operation phase width that is a state in which chopping operation is performed by the semiconductor switch (104) or a chopping pause phase width that is a state in which chopping by the semiconductor switch (104) is paused becomes a predetermined phase width set in accordance with load conditions and a command from the outside.

Description

Control device for rectifier circuit device and rectifier circuit device

The present invention relates to a control device for a rectifier circuit device that rectifies alternating current from an alternating current power source into direct current, and more particularly, to a rectifier circuit device that rectifies alternating current from a single-phase alternating current power source such as home to form substantially direct current. The present invention relates to a control device and a rectifier circuit device.

The rectifier circuit device according to the present invention is applied to a circuit device for driving a direct current load, and a device for converting the formed direct current again to an alternating current of an arbitrary frequency by an inverter circuit to drive a motor as a load at variable speed. Be done. The rectifier circuit device according to the present invention constitutes, for example, a heat pump by compressing a refrigerant with a compressor, and is applied to a device that performs cooling, heating, refrigeration of food or the like, and is included in the power supply current in such a device. The load on the transmission system is reduced by reducing the harmonic components to be reduced and improving the power factor to perform drive control with high efficiency.

In general, various types of rectifier circuit devices of this type have been proposed (see, for example, Patent Document 1). FIG. 18 is a circuit diagram showing a configuration of a rectifier circuit device disclosed in Patent Document 1, and FIG. 19 is a block diagram showing a configuration of a control unit in the rectifier circuit device of FIG.

In the rectifier circuit device shown in FIG. 18, both output terminals of the AC power supply 1 form a closed circuit by the on state of the semiconductor switch 3c via the rectifier bridge 2 and the reactor 3a, and charge the reactor 3a with current. When the semiconductor switch 3c is turned off, a current is supplied to the load 4 by the diode 3b. With this configuration, the rectifier circuit device of FIG. 18 has a configuration in which the power supply current flows even in a period when the instantaneous voltage of the AC power supply 1 is low, the harmonic component of the power supply current decreases, and the power factor is improved.

However, in the conventional rectifier circuit device, the semiconductor switch 3 c is finely turned on / off at a frequency sufficiently higher than the frequency of the AC power supply 1 to chop the AC voltage of the AC power supply 1 (hereinafter, “semiconductor When the switch is operated for chopping operation or “chopping by semiconductor switch”, a current flows through the semiconductor switch 3c, which causes a problem of circuit loss.

In order to solve this problem, a method has been proposed in which the semiconductor switch 3c is not chopping constantly, but chopping only during a specific period of the AC phase and rested for the remaining period (for example, see Patent Document 1). .

In the rectifier circuit device shown in FIG. 18, the AC voltage from AC power supply 1 is rectified by rectifier bridge 2 and converted to a DC voltage including pulsation, and then the power is smoothed through reactor 3a and diode 3b. The capacitor 3 d and the load 4 are supplied. Further, in FIG. 18, a rectifier circuit device with a power factor improving function by the known step-up chopper circuit 3 can be obtained by configuring so that the output voltage from the rectifier bridge 2 can be shorted by the semiconductor switch 3c via the reactor 3a. It is configured. In the rectifier circuit device shown in FIG. 18, the step-up chopper circuit 3 detects the input current by the input current detector 6 and the input current detection unit 10, and the input voltage detected by the input voltage detection unit 11 of the waveform of the input current The semiconductor switch 3c is subjected to chopping operation so as to have the same shape as the waveform (power supply voltage waveform), and the magnitude of the input current is adjusted so that the output voltage becomes a desired voltage.

In particular, Patent Document 1 proposes reducing the loss of the circuit by chopping the semiconductor switch only in the minimum section for reducing the number of harmonics. FIG. 19 is a block diagram showing a control method for the proposal. In FIG. 19, the phase of the power supply voltage is detected by the power supply zero cross detection means 5, and the chopping operation of the semiconductor switch 3c of FIG. 18 is permitted only for a fixed period by the pulse counter 13a. Is held to be off. By this control method, a rectifier circuit device with low loss without increasing the power supply harmonics is realized.

Moreover, in the control method of the rectifier circuit device of Patent Document 1, although the configuration of requiring the waveform of the power supply voltage, control for realizing the same operation by the predetermined waveform without using the waveform of the power supply voltage A method has also been proposed (see, for example, Patent Document 2). Furthermore, a simple method has also been proposed which aims to exhibit the same effect without having a target current waveform (see, for example, Patent Document 3).

In the case of the rectifier circuit device shown in FIG. 18, the input current is substituted by the current after being rectified once, information on the absolute value of the input current is obtained, and the magnitude of this absolute value is calculated. It is a configuration to adjust. It is widely known that adjusting the magnitude of the absolute value of the input current in this manner is equivalent to adjusting the amplitude of the input current.

JP 2005-253284 A Unexamined-Japanese-Patent No. 2007-129849 JP 2000-224858 A JP, 2001-045763, A

In the configuration of the rectifier circuit device according to the prior art, the output voltage is controlled to be constant under the condition that the load is determined, and the period during which the semiconductor switch is chopping is also fixed. Therefore, when the detected output voltage includes an error, the current waveform is changed. For example, in the case where an alternating current with an effective value of 200 V is rectified to obtain a direct current of about 280 V, the current waveform changes largely when the DC voltage changes by only 1 V. The accuracy of 1 V with respect to 280 V of the DC voltage corresponds to 0.3%, and in the case of dividing the voltage by resistors to form a low voltage, a resistor with very high accuracy is required. Therefore, in the conventional rectifier circuit device, in consideration of the detection accuracy of the output voltage, it is necessary to set the chopping period longer so as to reduce harmonics even in the changed current waveform. Therefore, such a conventional rectifier circuit device has a problem that the loss of the circuit increases.

In addition, although the control method in such a conventional rectifier circuit device is generally realized using a digital computer, in order to realize voltage control of a DC voltage with high accuracy, the DC voltage has high resolution, that is, the number of bits. A large number of analog-to-digital conversion (hereinafter referred to as "AD conversion") units are required, which increases the circuit load. Even in this case, it is necessary to set a longer chopping period to slightly increase the loss of the circuit so that harmonics are reduced even in the changed current waveform, in consideration of detection accuracy which can actually be detected by the control circuit. Have the challenge of

Furthermore, in such a conventional rectifier circuit device, the loss of the circuit decreases as the output voltage decreases, but if it is attempted to set the output voltage to a voltage lower than the instantaneous value of the power supply voltage, the semiconductor switch is chopping operated. Even if the alternating voltage in the period is lower than the output voltage, a phenomenon occurs in which the output voltage rises due to the step-up operation during the period in which the semiconductor switch is subjected to the chopping operation. For this reason, in the conventional rectifier circuit device, there is a problem that it is difficult to set a lower output voltage with less circuit loss.

Further, in such a conventional rectifier circuit device, the chopping period is uniformly set, and the chopping period is set for the assumed maximum input power. For this reason, such a conventional rectifier circuit device has to execute a prescribed chopping operation even in a situation where the input power is small and there is room for the regulation level of the power supply harmonic current, and as a result, the circuit The problem is that we can not minimize the loss of

The object of the present invention is to solve the above-mentioned problems, and to reduce the power supply harmonic current according to the status of the connected load or an external command regardless of the detection accuracy of the output voltage. It is an object of the present invention to provide a control device and a rectifier circuit device of a rectifier circuit device which can reduce the loss of the circuit.

The control device of the rectifier circuit device according to the present invention is
The chopping operation of the semiconductor switch shorts or opens the alternating voltage from the single phase alternating current power supply or the pulsating voltage obtained by rectifying the alternating current voltage through the reactor to rectify the single phase alternating current power supply into the direct current voltage. Control device of the rectifier circuit device for supplying power to the load,
The controller is
A waveform forming unit that forms a target current waveform having the same frequency as the waveform of the AC voltage;
An alternating current detection unit that detects an alternating current flowing from the single-phase alternating current power supply;
A DC voltage detection unit that detects the DC voltage;
A first control unit configured to control a chopping operation of the semiconductor switch such that a waveform of the detected alternating current substantially becomes the target current waveform;
A second control unit configured to control an amplitude of the target current waveform such that the detected DC voltage substantially becomes a predetermined target DC voltage;
The predetermined target DC voltage is controlled such that the chopping operation phase width in which the semiconductor switch is in the chopping operation state or the chopping pause phase width in which the semiconductor switch is in the chopping pause state is substantially equal to the predetermined phase width. And a third control unit.

The rectifier circuit device according to the present invention is
The chopping operation of the semiconductor switch shorts or opens the alternating voltage from the single phase alternating current power supply or the pulsating voltage obtained by rectifying the alternating current voltage through the reactor to rectify the single phase alternating current power supply into the direct current voltage. A rectifier circuit device for supplying power to the load,
A waveform forming unit that forms a target current waveform having the same frequency as the waveform of the AC voltage;
An alternating current detection unit that detects an alternating current flowing from the single-phase alternating current power supply;
A DC voltage detection unit that detects the DC voltage;
A first control unit configured to control a chopping operation of the semiconductor switch such that a waveform of the detected alternating current substantially becomes the target current waveform;
A second control unit configured to control an amplitude of the target current waveform such that the detected DC voltage substantially becomes a predetermined target DC voltage;
The predetermined target DC voltage is controlled such that the chopping operation phase width in which the semiconductor switch is in the chopping operation state or the chopping pause phase width in which the semiconductor switch is in the chopping pause state is substantially equal to the predetermined phase width. And a third control unit.

According to the present invention, it is possible to change a desired phase width in accordance with the status of a connected load or an external command, and a chopping operation to compare with a desired phase width regardless of the load fluctuation status. To provide a control device and a rectifier circuit device of a rectifier circuit device capable of realizing a rectification operation with less circuit loss and less harmonic current by accurately measuring a phase width or chopping idle phase width. Can.

FIG. 1 is a circuit diagram showing a configuration of a rectifier circuit device according to a first embodiment of the present invention. FIG. 2A is a block diagram showing a configuration of a control circuit in the rectifier circuit device of FIG. FIG. 2B is a diagram showing a modification of control in the rectifier circuit device of FIG. 1, and is a block diagram showing a case where an output signal of a waveform shaper is used in processing of a chopping phase detector of a control circuit. FIG. 2C is a diagram showing a modified example of control in the rectifier circuit device of FIG. 1 and is a block diagram showing a case where the output of the current detector is used in the processing of the chopping phase detector of the control circuit. FIG. 2D is a diagram showing a modification of control in the rectifier circuit device of FIG. 1, and is a block diagram showing a case where the output of the DC voltage detector is used in the processing of the chopping phase detector of the control circuit. FIG. 2E is a diagram showing a modified example of control in the rectifier circuit device of FIG. 1, and is a block diagram showing a case where the output of the PWM modulator is used in the processing of the chopping phase detector of the control circuit. FIG. 3A is a characteristic diagram of a target phase width setting unit when the desired phase width is a chopping operation phase width in the rectifier circuit device according to the present invention. FIG. 3B is a characteristic diagram of a target phase width setting unit when the desired phase width is the chopping pause phase width in the rectifier circuit device according to the present invention. FIG. 4A is a diagram for explaining a control operation according to a first operation example of the control device in the rectifier circuit device of FIG. 1, and (a) alternating voltage (hereinafter referred to as AC voltage) and rectified; A signal indicating the relationship with a direct current voltage (hereinafter referred to as a DC voltage), (b) a target current waveform to be controlled, and (c) an alternating current after actual control (hereinafter referred to as an AC current). FIG. FIG. 4B is a diagram for explaining a control operation according to a second operation example of the control device in the rectifier circuit device of FIG. 1, and (a) relationship between AC voltage and DC voltage after rectification; b) A signal waveform diagram showing a target current waveform to be controlled and (c) an AC current after actual control. FIG. 5A is a diagram for explaining a control operation according to a third operation example of the control device in the rectifier circuit device of the second embodiment of the present invention, and (a) AC voltage and DC voltage after rectification FIG. 7 is a signal waveform diagram showing the relationship of (b) a target current waveform to be controlled and (c) an AC current after actual control. FIG. 5B is a diagram for explaining the control operation according to the fourth operation example of the control device in the rectifier circuit device of the second embodiment of the present invention, and (a) AC voltage and DC voltage after rectification FIG. 7 is a signal waveform diagram showing the relationship of (b) a target current waveform to be controlled and (c) an AC current after actual control. FIG. 6A is a diagram for explaining the control operation according to the fifth operation example of the control device in the rectifier circuit device of the embodiment 3 of the present invention, and (a) AC voltage and DC voltage after rectification FIG. 7 is a signal waveform diagram showing the relationship of (b) a target current waveform to be controlled and (c) an AC current after actual control. FIG. 6B is a diagram for explaining the control operation according to the sixth operation example of the control device in the rectifier circuit device of the embodiment 3 of the present invention, and (a) AC voltage and DC voltage after rectification FIG. 7 is a signal waveform diagram showing the relationship of (b) a target current waveform to be controlled and (c) an AC current after actual control. FIG. 7A is a diagram for explaining a control operation according to a seventh operation example of the control device in the rectifier circuit device of the fourth embodiment of the present invention, and (a) AC voltage and DC voltage after rectification FIG. 7 is a signal waveform diagram showing the relationship of (b) a target current waveform to be controlled and (c) an AC current after actual control. FIG. 7B is a diagram for explaining the control operation according to the eighth operation example of the control device in the rectifier circuit device of the fourth embodiment of the present invention, and (a) AC voltage and DC voltage after rectification FIG. 7 is a signal waveform diagram showing the relationship of (b) a target current waveform to be controlled and (c) an AC current after actual control. FIG. 8A is a diagram for explaining the control operation according to the ninth operation example of the control device in the rectifier circuit device of the fifth embodiment of the present invention, and (a) AC voltage and DC voltage after rectification; FIG. 7 is a signal waveform diagram showing the relationship of (b) a target current waveform to be controlled and (c) an AC current after actual control. FIG. 8B is a diagram for explaining the control operation according to the tenth operation example of the control device in the rectifier circuit device of the fifth embodiment of the present invention, and (a) AC voltage and DC voltage after rectification FIG. 7 is a signal waveform diagram showing the relationship of (b) a target current waveform to be controlled and (c) an AC current after actual control. FIG. 9A is a diagram for explaining a control operation according to an eleventh operation example of the control device in the rectifier circuit device of the sixth embodiment of the present invention, and (a) AC voltage and DC voltage after rectification FIG. 7 is a signal waveform diagram showing the relationship of (b) a target current waveform to be controlled and (c) an AC current after actual control. FIG. 9B is a diagram for explaining the control operation according to the twelfth operation example of the control device in the rectifier circuit device of the sixth embodiment of the present invention, and (a) AC voltage and DC voltage after rectification FIG. 7 is a signal waveform diagram showing the relationship of (b) a target current waveform to be controlled and (c) an AC current after actual control. FIG. 10A is a diagram for illustrating a control operation according to a thirteenth operation example of the control device in the rectifier circuit device of the sixth embodiment of the present invention, and (a) AC voltage and DC voltage after rectification FIG. 7 is a signal waveform diagram showing the relationship of (b) a target current waveform to be controlled and (c) an AC current after actual control. FIG. 10B is a diagram for explaining the control operation according to the fourteenth operation example of the control device in the rectifier circuit device of the sixth embodiment of the present invention, and (a) AC voltage and DC voltage after rectification FIG. 7 is a signal waveform diagram showing the relationship of (b) a target current waveform to be controlled and (c) an AC current after actual control. FIG. 10C is a diagram for illustrating the control operation according to the fifteenth operation example of the control device in the rectifier circuit device of the sixth embodiment of the present invention, and (a) AC voltage and DC voltage after rectification FIG. 7 is a signal waveform diagram showing the relationship of (b) a target current waveform to be controlled and (c) an AC current after actual control. FIG. 10D is a diagram for explaining the control operation according to the sixteenth operation example of the control device in the rectifier circuit device of the sixth embodiment of the present invention, and (a) AC voltage and DC voltage after rectification FIG. 7 is a signal waveform diagram showing the relationship of (b) a target current waveform to be controlled and (c) an AC current after actual control. FIG. 11 is a circuit diagram showing a configuration of a rectifier circuit device according to a seventh embodiment of the present invention. FIG. 12 is a circuit diagram showing a configuration of a rectifier circuit device according to an eighth embodiment of the present invention. FIG. 13 is a circuit diagram showing a configuration of a rectifier circuit device according to a ninth embodiment of the present invention. FIG. 14A is a diagram for explaining a first operation example of the binarization processing of the voltage level comparator in the rectifier circuit device according to the first to ninth embodiments of the present invention, in which It is a signal waveform diagram which shows the relationship with a threshold voltage (Vth), and the binary signal from (b) voltage level comparator. FIG. 14B is a diagram for explaining a second operation example of the binarization processing of the voltage level comparator in the rectifier circuit device according to the first to ninth embodiments of the present invention; It is a signal waveform diagram which shows the relationship with a threshold voltage (Vth), and the binary signal from (b) voltage level comparator. FIG. 15 is a block diagram showing a detailed configuration of a control circuit in a rectifier circuit device according to a tenth embodiment of the present invention. FIG. 16 is a block diagram showing a detailed configuration of a low pass filter computing unit (hereinafter referred to as “LPF computing unit”) in the rectifier circuit device of FIG. FIG. 17 is a diagram showing the operation of the rectifier circuit device of FIG. 15, and (a) AC current (Iac) from AC power supply, (b) DC voltage (Vdc), (c) AD converter FIG. 7 is a signal waveform diagram showing an AD conversion value (Vad) (the DC voltage Vdc is indicated by a dotted line). It is a circuit diagram which shows the structure of the conventional rectifier circuit apparatus. It is a block diagram which shows the detailed structure of the control part in the conventional rectifier circuit apparatus of FIG.

Hereinafter, each aspect of the control device of the rectifier circuit device according to the present invention and the rectifier circuit device will be described. In the following description of each aspect, reference numerals and the like in parentheses represent reference numerals and the like of related elements in the respective embodiments to be described later, but the present invention is not limited to the configurations of the respective embodiments.
The control device for a rectifier circuit device according to the first aspect of the present invention is
The chopping operation of the semiconductor switch shorts or opens the alternating voltage from the single phase alternating current power supply or the pulsating voltage obtained by rectifying the alternating current voltage through the reactor to rectify the single phase alternating current power supply into the direct current voltage. Control device of the rectifier circuit device for supplying power to the load,
The controller is
A waveform forming unit (201, 202) for forming a target current waveform having the same frequency as the waveform of the AC voltage;
An alternating current detection unit (103) for detecting an alternating current flowing from the single-phase alternating current power supply;
A DC voltage detection unit (110) for detecting the DC voltage;
A first control unit (208, 209, 210, 211) for controlling the chopping operation of the semiconductor switch so that the waveform of the detected alternating current (Iac) substantially becomes the target current waveform;
A second control unit (206, 207) for controlling the amplitude of the target current waveform such that the detected DC voltage (Vdc) substantially becomes a predetermined target DC voltage (Vdc ^* );
The predetermined value is set such that the chopping operation phase width (θw _ON ) in which the semiconductor switch is in the chopping operation state or the chopping pause phase width (θw _OFF ) in which the semiconductor switch is in the chopping pause state becomes substantially a predetermined phase width. And a third control unit (203, 204, 205, 212) for controlling the target DC voltage of

In the control apparatus for a rectifier circuit device according to the second aspect of the present invention, the load state is such that the predetermined phase width in the first aspect is in the range of 0 degrees to 180 degrees with respect to a power supply half cycle Alternatively, it is configured to be changed and set in accordance with an external command.

In the control apparatus for a rectifier circuit device according to a third aspect of the present invention, the load status in the second aspect is the value of the alternating current, the input power calculated based on the alternating current, or It is configured as indicated by the output power of the rectifier circuit device.

In the control device for a rectifier circuit device according to the fourth aspect of the present invention, the polarity of the alternating voltage is fixed in the third control unit according to any one of the first to third aspects. The predetermined target DC voltage so that the chopping pause phase width or the instantaneous value of the chopping operation phase width detected within the period, or the average value by the number of times set in advance, substantially becomes the predetermined phase width Are configured to control the

In the control device for a rectifier circuit device according to a fifth aspect of the present invention, the third control unit according to any one of the first to third aspects is characterized in that the direct current in the predetermined period is lowest. The predetermined target DC voltage so that the chopping pause phase width or chopping operation phase width detected within a period in which the polarity of the AC voltage is fixed, including voltage time, is substantially equal to the predetermined phase width. Are configured to control the

In the control device for a rectifier circuit device according to a sixth aspect of the present invention, the third control unit according to any one of the first to third aspects is the largest alternating current in a predetermined period. The predetermined target DC voltage is set so that the chopping pause phase width or chopping operation phase width detected within a period in which the polarity of the AC voltage is fixed, including current, is substantially equal to the predetermined phase width. It is configured to control.

In the control device for a rectifier circuit device according to the seventh aspect of the present invention, the polarity of the alternating voltage is fixed in the third control unit according to any one of the first to sixth aspects. When a plurality of chopping operation phase widths or a plurality of chopping pause phase widths exist in a period, any phase width in the period or a total phase width is substantially a predetermined phase. The predetermined target DC voltage is controlled to have a width.

In the control device for a rectifier circuit device according to an eighth aspect of the present invention, the target current waveform according to any one of the first to seventh aspects has an instantaneous absolute value of the target current waveform (A) Within a period in which the polarity of the AC voltage is fixed, (a) From the start point of the period to a predetermined midpoint, at least increase or at least increase with time, and a partial period And (b) from the midpoint to the end point at least decrease or at least decrease with time and substantially constant so as to be constant over a period of time. After monotonically decreasing, it is set to have a period which becomes zero.

In the control apparatus for a rectifier circuit device according to a ninth aspect of the present invention, the target current waveform according to any one of the first to seventh aspects has an instantaneous absolute value of the target current waveform (A) Within a period in which the polarity of the alternating voltage is fixed, (a) from the start point of the period to a predetermined first intermediate point has a period which becomes zero with the passage of time, (b) From the first midpoint to the predetermined second midpoint, at least increasing, or at least increasing, and substantially monotonically increasing so as to be constant over a period of time, and (c) the second From the middle point to the end point is set to have a period that decreases at least or at least decreases with time and substantially monotonically decreases and then becomes zero so as to be constant in part of the period doing.

The control device for a rectifier circuit device according to a tenth aspect of the present invention is the control method according to any one of the first to ninth aspects, wherein the AC voltage is compared with a predetermined threshold voltage. It further comprises a phase detection unit (109) that generates a binary signal,
The waveform forming unit detects a cycle and a phase of the AC voltage based on the binary signal, and a target current waveform having the same frequency as the waveform of the AC voltage based on the cycle and the phase of the detected AC voltage. Form
The third control unit is configured to detect a chopping operation phase width in which the semiconductor switch is in the chopping operation state or a chopping pause phase width in which the semiconductor switch is in the chopping suspension state based on the binary signal. ing.

In the control device for a rectifier circuit device according to an eleventh aspect of the present invention, in any one of the first to tenth aspects, the control device further includes: the DC voltage detection unit; An AD conversion unit (230) for AD converting the detected DC voltage to a digital voltage, and between the AD conversion unit and the second control unit, And a calculation unit (231) for outputting the voltage of the calculation result as the detected direct current voltage to the second control unit after the low-pass filter calculation is performed on the digital voltage.

The control device of a rectifier circuit device according to a twelfth aspect of the present invention is set such that the sampling frequency of the AD converter in the eleventh aspect is sufficiently higher than the frequency of the single-phase AC power supply. ing.

In the control device for a rectifier circuit device according to the thirteenth aspect of the present invention, the low-pass filter computation in the eleventh aspect or the twelfth aspect further includes “(2 ⁿ −1) / After multiplying by a factor (2 ⁿ ) (where n is an integer), it is added to the input digital voltage and executed using the value of the addition result as the next calculation result.

A rectifier circuit device according to a fourteenth aspect of the present invention includes the control device of the rectifier circuit device according to any one of the first to thirteenth aspects.

According to the configuration of each of the above aspects, even if there is an error in the detection accuracy of the DC voltage, the DC voltage is adjusted to a relatively appropriate value, and the current waveform becomes the same as the input voltage waveform, and the load condition Or, by changing the desired phase width according to an external command, or by accurately measuring the chopping operation phase width or chopping pause phase width to be compared with the desired phase width regardless of the load fluctuation state. It is always possible to realize a rectification operation with low circuit loss and low harmonic current.

Also, with a sampling frequency sufficiently higher than the frequency of the AC power supply, the DC voltage is converted into a digital signal by the AD conversion unit and detected, and the obtained digital signal is subjected to low pass filter calculation (LPF calculation) for each period. To add minute information below the resolution to the digital signal so that it interpolates, and using the digital signal interpolated from the small information as direct current voltage information, the phase width for which chopping is actually made becomes the desired value. In addition, the digital signal which has interpolated the minute information is adjusted. Even if there is fluctuation in the power supply frequency component contained in the smoothed voltage of the DC voltage and the resolution of the digital information is coarse, the digital signal is dispersed due to the fluctuation, so a digital signal equivalent to high resolution is obtained on average be able to. As a result, even if coarse resolution AD conversion means are used, the average value of the DC voltage can be adjusted with high accuracy, and a rectification operation with less loss and less harmonic current can be realized.

Hereinafter, embodiments of a rectifier circuit device and a control circuit of the present invention will be described with reference to the attached drawings. The rectifier circuit device and control circuit of the present invention are not limited to the configurations of the rectifier circuit device and control circuit described in the following embodiments, and are equivalent to the technical idea described in the following embodiments. Including those based on the technical ideas of Further, in each of the following embodiments, components having the same functions will be described with the same reference numerals.

Embodiment 1
FIG. 1 is a circuit diagram showing a configuration of a rectifier circuit device according to a first embodiment of the present invention. In FIG. 1, a single loop is configured by shorting both output terminals of single-phase AC power supply 1 with semiconductor switch 104 via reactor 102. The current detector 103, which is an alternating current detection unit, detects the current of the loop, and outputs a signal indicating the detected current value Iac to the control circuit 100. When the semiconductor switch 104 is turned on, the current of the reactor 102 is increased. On the other hand, when the semiconductor switch 104 is turned off, the current flowing to the reactor 102 is rectified by the diode bridge circuit 105, and the rectified current flows to the smoothing capacitor 106 and the load 4 to drive the load 4. The DC voltage Vdc across the smoothing capacitor 106 applied to the load 4 is detected by the DC voltage detector 110, and the DC voltage detector 110 outputs a signal indicating the detected DC voltage Vdc to the control circuit 100.

The voltage level comparator 109, which is a phase detection unit of the AC voltage input from the AC power supply 1, compares the AC voltage level of the AC power supply 1 with a predetermined threshold voltage to obtain the threshold voltage or more. Is generated and output to the control circuit 100. The control circuit 100 detects the phase of the AC voltage output from the AC power supply 1 based on the period and the phase of the binary signal Scom. The control circuit 100 generates a target current waveform having substantially the same frequency as the AC voltage and having a similar shape to the AC voltage based on the phase of the detected AC voltage, and is detected by the current detector 103. The semiconductor switch 104 is controlled to chopping so that the current value Iac approaches the similar shape of the generated target current waveform.

Furthermore, control circuit 100 is similar to the target current waveform to be generated according to the deviation so that DC voltage Vdc detected by DC voltage detector 110 becomes the desired voltage set in control circuit 100. Adjust the ratio. Here, if the actual DC voltage Vdc is lower than the desired DC voltage, the control circuit 100 increases the similarity ratio of the target current waveform to control so as to be a large current, and the actual DC voltage Vdc is desired. If it is higher than the DC voltage, control is made to be a small current. Further, the control circuit 100 detects a phase width driving the semiconductor switch 104 by pulse width modulation (hereinafter referred to as "PWM") based on the chopping state of the semiconductor switch 104, and the phase width and a desired value. And the desired DC voltage value is adjusted according to the deviation.

FIG. 2A is a block diagram showing the detailed configuration of the control circuit 100 of FIG. In the control circuit 100 of FIG. 2A, the final control target as the control system is to control the chopping operation phase width θw _{ON in} which chopping driving is performed to a desired phase width θw _ON ^* from the target phase width setter 203. It is. First, the AC voltage phase detector 201 detects an AC phase based on a binary signal Scom binarized by comparing the voltage level of the AC power supply 1 with a predetermined threshold voltage Vth, and detects AC. A signal indicating the phase is output to the target current waveform shaper 202 and the chopping phase width detector 212. The details of the specific operation of the AC voltage phase detector 201 will be described later. Next, based on the signal indicating the AC phase, the target current waveform former 202 generates a predetermined target current waveform, which will be described in detail later, and outputs it to the multiplier 208.

In the first embodiment according to the present invention, a waveform forming unit that forms a target current waveform having the same frequency as the waveform of AC voltage by AC voltage phase detector 201 and target current waveform shaper 202 in control circuit 100 is provided. It is configured.

The chopping phase width detector 212 is an AC voltage indicated by the signal from the AC voltage phase detector 201 based on the original signal of the chopping drive signal Sch for the semiconductor switch 104 output from the Iac compensation operator 210 to the PWM modulator 211. Phase width in the chopping state (hereinafter referred to as “chopping operation phase width” or simply “chopping phase width”) θw _ON is detected, and a signal indicating the chopping phase width θw _ON is subtracted from the phase of the phase Output to 204. On the other hand, the target phase width setting unit 203 subtracts a signal indicating a desired chopping phase width θw _ON ^* according to a preset relationship from the actual current value Iac detected by the current detector 103 which is a current detection unit. Output to

Here, FIG. 3A shows the desired chopping phase width θw _ON ^* output from the target phase width setter 203 and the actual current value Iac detected by the current detector 103 input to the target phase width setter 203. And an example of the relationship with

As shown in FIG. 3A, the desired chopping phase width θw _ON ^* increases as the actual current value Iac increases. With such characteristics, it is possible to give a characteristic that emphasizes reduction of the harmonic current at high input while emphasizing loss reduction since the magnitude of the harmonic current itself is small at low input. As a result, it is possible to provide characteristics aiming for loss reduction and suppression of harmonic current.

In the characteristics shown in FIG. 3A, the front and back are made flat, and between them is assumed to be connected by a smooth straight line, but as characteristics showing the relationship between the chopping phase width θw _ON ^* and the current value Iac, it is shown in FIG. It is not limited to the following characteristics.

Further, in the characteristic diagram of FIG. 3A, the horizontal axis is described as the actual current value Iac, but the input power calculated based on the current value Iac or the current detector 112 for detecting the current flowing to the load 4 Similar results can be obtained using the output and the output power of the rectifier circuit device obtained from the output of the DC voltage detector 110 which is the DC voltage detector.

The subtractor 204 is a so-called phase comparator, which subtracts the desired chopping phase width θw _ON ^* from the actual chopping phase width θw _ON to calculate the deviation of the phase width and phase the signal indicating the deviation It is output to the width compensation computing unit 205. The phase width compensation computing unit 205 generates a command voltage Vdc ^* of the DC voltage to be output by the rectifier circuit device by performing a predetermined compensation operation to keep the phase width of the PWM drive state stable. A signal indicating command voltage Vdc ^* is output to subtractor 206. On the other hand, a signal indicating the actual output DC voltage Vdc detected by the DC voltage detector 110 which is a DC voltage detection unit is input to the subtractor 206.

The subtractor 206 subtracts the actual output DC voltage Vdc from the command voltage Vdc ^* of the DC voltage to calculate a voltage deviation, generates a signal indicating the voltage deviation, and outputs the signal to the Vdc compensation computing unit 207. The Vdc compensation computing unit 207 multiplies the signal indicating the voltage deviation after the compensation operation by executing the compensation operation for the actual DC voltage Vdc to substantially coincide with the command voltage Vdc ^* and become stable. Output to the signal generator 208. The multiplier 208 multiplies the target current waveform from the target current waveform former 202 by the voltage deviation after the compensation operation, forms an instantaneous current command value Iac ^* which is the multiplication result, and outputs the current command value Iac ^* to the subtractor 209 Do. In the operation of the multiplier 208, the amplitude of the target current waveform is increased when the actual voltage Vdc is lower than the command voltage Vdc ^*, while the amplitude of the target current waveform is increased when the actual voltage Vdc is higher than the command voltage Vdc ^*. Reduce

The subtractor 209 subtracts the actual current value Iac detected by the current detector 103 from the instantaneous current command value Iac ^* to output a signal indicating a current deviation as a subtraction result to the Iac compensation computing unit 210. Do. The Iac compensation operation unit 210 performs a predetermined compensation operation so that the current input from the AC power supply 1 stably and promptly substantially matches the current command value Iac ^* , and the current deviation after the compensation operation is calculated. The signal shown is output to the PWM modulator 211 and the chopping phase width detector 212. The PWM modulator 211 generates a chopping drive signal Sch for turning on / off the semiconductor switch 104 by performing PWM modulation on the current deviation after the compensation operation indicated by the input signal, and outputs the chopping drive signal Sch to the semiconductor switch 104. . On the other hand, as described above, the chopping phase width detector 212 generates the AC voltage phase detector 201 based on the original signal of the chopping drive signal Sch for the semiconductor switch 104 output from the Iac compensation operation unit 210 to the PWM modulator 211. The chopping phase width θw _ON is detected on the basis of the phase of the AC voltage indicated by the signal from the signal D.2 and a signal indicating the chopping phase width θw _ON is output to the subtractor 204. This constitutes a control loop of chopping phase width.

In the control circuit 100 configured to chopping drive control of the semiconductor switch 104 configured as described above, the loops (204 to 205, 206, 207, 208, 209, 210, and 212 on the right side of the subtractor 204 in FIG. DC) voltage Vdc so that the chopping phase width detected by the chopping phase width detector 212 substantially matches the target phase width set by the target phase width setter 203). Is controlled. Also, it is detected by the DC voltage detector 110 in a loop on the right side of the subtractor 206 in FIG. 2A (that is, a loop that returns to 206 via 206 to 207, 208, 209, 210, 211, 104, 110). The amplitude of the target current is controlled to perform chopping drive control so that the DC voltage Vdc substantially matches the desired DC voltage Vdc ^* indicated by the phase width compensation computing unit 205. Furthermore, in the loop on the right side of the subtractor 209 in FIG. 2A (the loop from 209 to 210, 211, 104, and 103 to return to 209), the current Iac detected by the current detector 103 is the target current waveform The chopping drive is controlled so as to substantially match the target current Iac ^* generated based on the target current waveform formed by the former 202.

FIG. 4A is a diagram for explaining a control operation according to a first operation example of the control device in the embodiment 1, wherein (a) relationship between AC voltage and DC voltage after rectification; (b) It is a signal waveform diagram which shows the target current waveform which should be controlled, and (c) AC current after actually controlling. FIG. 4B is a diagram for explaining the control operation according to the second operation example of the control device in the first embodiment, and (a) relationship between AC voltage and DC voltage after rectification; b) A signal waveform diagram showing a target current waveform to be controlled and (c) an AC current after actual control.

In the first operation example of FIG. 4A, the DC voltage to be output is relatively low, and the chopping phase width (for example, the minimum phase width) θw _ON for the semiconductor switch 104 is smaller than the desired phase width θw _ON ^* It is the case. At this time, since the phase period in which the AC voltage is higher than the DC voltage increases, the current flowing from the AC power supply 1 to the DC side via the reactor 102 and the diode bridge circuit 105 increases. Therefore, the waveform of the AC current is sharpened, and the harmonic component of the AC current is increased.

On the other hand, in the second operation example of FIG. 4B, the output DC voltage is relatively high, and the chopping phase width (for example, maximum phase width) θw _ON for the semiconductor switch 104 is larger than the desired phase width θw _ON ^* This is the case. At this time, since the phase period in which the AC voltage is higher than the DC voltage decreases in comparison with the first operation example, the current flowing from the AC power supply 1 to the DC side via the reactor 102 and the diode bridge circuit 105 also decreases. , The harmonic component of the AC current is reduced. However, in the second operation example of FIG. 4B, the period during which the semiconductor switch 104 is chopping is increased as compared to the waveform in the first operation example of FIG. Resulting in.

Here, if distortion is included in the AC voltage from the AC power supply 1, a section in which chopping is performed may appear a plurality of times during a half cycle of the AC voltage. In that case, the chopping phase width detector 212 may select the chopping phase width close to 0 degree or 180 degrees of the phase of the AC voltage as the control chopping phase width to perform the chopping control. Also, the chopping phase width detector 212 controls the phase width closer to the reference phase for determining the polarity of the AC current or the AC voltage instead of 0 degree or 180 degrees of the phase of the AC voltage. May be selected to perform the chopping control. Furthermore, the chopping phase width detector 212 may perform the chopping control by adding the plurality of obtained chopping phase widths and using the phase width of the addition result as the control chopping phase width.

In the configuration of the first embodiment according to the present invention, the control device in the rectifier circuit device includes, together with the control circuit 100, a current detector 103 which is an alternating current detection unit, and a current detector 112 which is a direct current detection unit. It includes a DC voltage detector 110 which is a DC voltage detection unit, and a voltage level comparator 109.

Further, the control circuit 100 in the first embodiment is functionally divided into a waveform shaping unit, a first control unit, a second control unit, and a third control unit.

The first control unit controls the chopping operation of the semiconductor switch 104 so that the waveform of the detected alternating current Iac substantially becomes the target current waveform. In the configuration of the first embodiment shown in FIG. 2A, the first control unit is composed of a multiplier 208, a subtractor 209, an Iac compensation operation unit 210, and a PWM modulator 211.

The second control unit controls the amplitude of the target current waveform so that the detected DC voltage Vdc substantially becomes a predetermined target DC voltage Vdc ^* . In the configuration of the first embodiment, the second control unit is configured of a subtractor 206 and a Vdc compensation computing unit 207.

The third control unit sets a predetermined target such that the chopping operation phase width in which the semiconductor switch 104 is in the chopping operation state or the chopping pause phase width in which the semiconductor switch 104 is in the chopping pause state is substantially the predetermined phase width. The DC voltage Vdc ^* is controlled. In the configuration of the first embodiment, the third control unit is configured of the target phase width setting unit 203, the subtractor 204, the phase width compensation computing unit 205, and the chopping phase width detector 212.

In the first embodiment, the target phase width setting unit 203 is configured to obtain a desired chopping phase width θw _ON ^* according to a preset relationship from the actual current value Iac detected by the current detector 103. It is also possible to cope with other configurations. For example, the target phase width setting unit 203 sequentially stores the maximum current (instantaneous value) obtained by the current detector 103 within the period in which the polarity of the AC voltage is fixed, and the most among the preset number. A large current may be extracted and used as the phase width setting current Iacp, and may be used instead of the actual current Iac. Alternatively, in the target phase width setting unit 203, the average value using the maximum current (instantaneous value) stored in the preset number of times may be used as the phase width setting current Iacp and used instead of the actual current Iac. Good.

Alternatively, in the rectifier circuit device, the target phase width setter 203 is calculated based on the input power calculated based on the actual current Iac, not the actual current Iac, or the DC voltage detector 110 and the current detector 112. Output power may be used.

When the load 4 is an inverter including a motor, an instruction signal (not shown) may be given from the outside so that a desired chopping phase width θw _ON ^* is switched by a rotation speed command to the motor. Alternatively, an instruction signal (not shown) is externally provided so that the desired chopping phase width θw _ON ^* is switched from the requirement of the entire system including the rectifier circuit device such as requiring a high power factor or a high DC voltage under a specific condition. It may be a method. In this method, the desired chopping phase width θw _ON ^* may be 180 degrees to perform the entire area switching. Furthermore, a method combining these methods may be used.

In the chopping phase width detector 212 according to the first embodiment, the AC voltage phase detector 201 is used based on the original signal of the chopping drive signal Sch for the semiconductor switch 104 output from the Iac compensation operator 210 to the PWM modulator 211. The chopping operation phase width .theta.w _ON is detected based on the phase of the AC voltage indicated by the signal C. However, as the present invention, for example, FIG. 2B, FIG. 2C, FIG. 2D or FIG. The same effects can be obtained even with the configuration as shown.

In the configuration shown in FIG. 2B, a waveform shaper 111 to which a chopping drive signal Sch is input is provided, and a binary signal of a portion in which the waveform shaper 111 continuously switches the chopping drive signal Sch and a portion in which the switching is stopped. And outputs the binary signal to the chopping phase width detector 212. The chopping phase width detector 212 extracts the chopping phase width from a portion corresponding to a portion in which switching of the binary signal is continuous based on the phase of the AC voltage indicated by the signal from the AC voltage phase detector 201 and extracts the chopping phase width. The chopping phase width is set to the chopping operation phase width θw _ON .

The configuration shown in FIG. 2B as described above also has the same effects as the configuration shown in FIG. 2A described above.

Further, in the configuration shown in FIG. 2C, the chopping phase width detector 212 detects the chopping phase width during the period in which the polarity is fixed and the actual current value Iac output from the current detector 103 during the measurement period. The chopping phase width at which the actual current value Iac is maximum may be extracted from a plurality of continuous measurement results in association with the maximum value, and the extracted chopping phase width may be set as the chopping operation phase width θw _ON .

The reason why the maximum value of the actual current value Iac is linked and stored is that the chopping phase width is controlled focusing on the current waveform where the power supply harmonic level becomes the largest since the power supply harmonic level is proportional to the input current Thus, the power supply harmonics are controlled to the target level or less.

In addition, the reason why the chopping phase width detector 212 extracts from a plurality of continuous measurement results is that the measurement value of the chopping phase width once is different when the load 4 has a characteristic with pulsation.

Furthermore, in the configuration shown in FIG. 2D, the chopping phase width detector 212 detects the chopping phase width during the period in which the polarity is fixed and the DC voltage Vdc output from the DC voltage detector 110 during the measurement period. The chopping phase width having the minimum DC voltage Vdc is extracted from a plurality of continuous measurement results in association with the minimum value, and the extracted chopping phase width is set as the chopping operation phase width θw _ON .

The level of power supply harmonics is proportional to the input current. If this relationship is replaced with the DC voltage Vdc, the voltage drop of the DC voltage Vdc becomes large at the place where the load is the largest. Therefore, in the configuration shown in FIG. 2D, power harmonics are stored by being correlated with the minimum value of DC voltage Vdc, focusing on the current waveform where the power supply harmonic level is maximized, and chopping phase width control. It can be controlled below the target level.

The reason why extraction is performed from a plurality of continuous measurement results is that, in the case where the load 4 has a characteristic with pulsation, the measurement values of the chopping phase width once are different.

When it comprises as mentioned above, also in the characteristic in which the load 4 has a pulsation, it has an effect similar to the structure shown to FIG. 2A.

Alternatively, in the configuration shown in FIG. 2E, the chopping phase width detector 212 measures the number of pulses which is the output of the PWM modulator 211 during the period in which the polarity is fixed, and chopping period is measured The chopping phase width may be calculated by multiplying the chopping phase width by the chopping operation phase width θw _ON . In the configuration shown in FIG. 2E, the power supply harmonic can be controlled to a target level or less by controlling the chopping phase width from the number of pulses actually driving the semiconductor switch.

Second Embodiment
Hereinafter, a rectifier circuit device according to a second embodiment of the present invention and a control device in the rectifier circuit device will be described.

In the rectifier circuit device according to the first embodiment described above, the chopping phase width θw _ON is detected and the DC voltage command Vdc ^* is adjusted using the phase width θw _ON . In the rectifier circuit device of mode 2, the phase width (hereinafter referred to as “chopping pause phase width”) θw _{OFF in} which chopping is in the pause state is detected, and the DC voltage command Vdc is detected using the chopping pause phase width θw _OFF. Similar effects can be obtained by adjusting ^* .

Therefore, the configurations of the rectifier circuit device and the control device of the second embodiment according to the present invention are substantially the same as the configurations of FIG. 1 and FIG. 2A described in the first embodiment, The second embodiment will be described using the same reference numerals as the reference numerals in the first embodiment.

However, the relationship between the desired chopping phase width θw _OFF ^* output from the target phase width setter 203 and the actual current value Iac detected by the current detector 103 input to the target phase width setter 203 is implemented. It is different from Form 1. The figure shows an example of the relationship between the desired chopping phase width θw _OFF ^* output from the target phase width setter 203 and the actual current value Iac detected by the current detector 103 input to the target phase width setter 203. Shown in 3B. FIG. 3B shows the relationship between the desired chopping phase width θw _OFF ^* output from the target phase width setter 203 and the actual current value Iac detected by the current detector 103 input to the target phase width setter 203. An example is shown.

The characteristic shown in FIG. 3B is a characteristic in which the desired chopping phase width θw _OFF ^* decreases as the actual current value Iac detected by the current detector 103 increases. With such characteristics, it is possible to give a characteristic that emphasizes reduction of the harmonic current at high input while emphasizing loss reduction since the magnitude of the harmonic current itself is small at low input. As a result, it is possible to provide characteristics aiming for loss reduction and suppression of harmonic current.

In the characteristic shown in FIG. 3B, the front and back are made flat, and between them is assumed to be connected by a smooth straight line, the characteristic showing the relationship between the chopping phase width θw _OFF ^* and the current value Iac is limited to this shape It is not a thing.

Further, in the characteristic diagram of FIG. 3B, the horizontal axis is described as the actual current value Iac, but the input power calculated based on the current value Iac or the current detector 112 for detecting the current flowing to the load 4 Similar results are obtained using the output and the output power of the rectifier circuit device obtained from the output and the output of the DC voltage detector 110.

FIG. 5A is a diagram for explaining a control operation according to a third operation example of the control device in the rectifier circuit device of the second embodiment of the present invention, and (a) AC voltage and DC voltage after rectification FIG. 7 is a signal waveform diagram showing the relationship of (b) a target current waveform to be controlled, and (c) an AC current after actual control. FIG. 5B is a diagram for explaining a control operation according to a fourth operation example of the control device in the rectifier circuit device of the second embodiment of the present invention, and (a) after the rectification with the AC voltage. It is a signal waveform diagram which shows the relationship with DC voltage, (b) target current waveform to be controlled, and (c) AC current after actual control.

In the third operation example of FIG. 5A, the output DC voltage is relatively low, and the chopping pause phase width (for example, maximum phase width) θw _{OFF in} which the semiconductor switch 104 is not chopping operated is large. On the other hand, in the fourth operation example of FIG. 5B, the chopping pause phase width (for example, minimum phase width) θw _{OFF in} which the output DC voltage is higher than in the third operation example and the semiconductor switch 104 is not chopping This is a case where the size is smaller than that of the third operation example. Since the chopping pause phase width θw _OFF is complementary to the chopping operation phase width θw _ON , the same function and effect can be obtained.

In addition, when distortion is included in the AC voltage from the AC power supply 1, a section in which chopping is performed may appear a plurality of times during a half cycle of the AC voltage. In such a case, the chopping phase width detector 212 selects the chopping pause phase width θw _OFF of the off period close to 90 degrees of the phase of the AC voltage as the chopping phase width for control and performs the chopping control. Good. Furthermore, the chopping phase width detector 212 may perform the chopping control by adding the plurality of chopping pause phase widths obtained above and using the phase width of the addition result as the control chopping phase width.

Although the characteristic diagrams of FIGS. 5A and 5B show waveforms of only half cycles of the AC voltage, as is apparent from FIGS. 4A and 4B and the prior art, the remaining half cycles also have absolute values. The waveform is the same as (instantaneous absolute value), and thus omitted.

In the second embodiment, the desired phase width setting unit 203 obtains the desired chopping pause phase width θw _OFF ^* from the actual current value Iac detected by the current detector 103 according to a preset relationship. However, other configurations are also possible. For example, the target phase width setting unit 203 sequentially stores the maximum current obtained by the current detector 103 within the period in which the polarity of the AC voltage is fixed, and extracts the largest current from the preset number of times. The phase width setting current Iacp may be used instead of the actual current Iac. Alternatively, the target phase width setting unit 203 may use an average value using the stored maximum current as the phase width setting current Iacp instead of the actual current Iac.

When the load 4 is an inverter including a motor, an instruction signal (not shown) may be given from the outside so that the desired chopping pause phase width θw _OFF ^* is switched by a rotation speed command to the motor. Alternatively, an instruction signal (not shown) is externally supplied so that the desired chopping pause phase width θw _OFF ^* is switched from the requirement of the entire system including a rectifier circuit device such as a high power factor or a high DC voltage desired in a specific condition. It may be a method of giving. In this case, the desired chopping pause phase width θw _OFF ^* may be set to 0 degrees to perform the entire region switching. Furthermore, a combined method of these methods may be used.

In the chopping phase width detector 212 according to the second embodiment, the AC voltage phase detector 201 is used based on the original signal of the chopping drive signal Sch for the semiconductor switch 104 output from the Iac compensation operation unit 210 to the PWM modulator 211. The chopping pause phase width θw _OFF is detected on the basis of the phase of the AC voltage indicated by the signal of FIG. 2B, but the present invention is described with reference to FIGS. 2B, 2C, and 2 described in the first embodiment, for example. The same function and effect can be obtained with the configuration as shown in 2D or FIG. 2E.

In the case where the configuration shown in FIG. 2B is applied, a waveform shaper 111 to which the chopping drive signal Sch is input is provided, and a portion where the waveform shaper 111 continuously switches the chopping drive signal Sch and a portion where the switching stops The binary signal is formed into a binary signal, and the binary signal is output to the chopping phase width detector 212. The chopping phase width detector 212 extracts the chopping pause phase width from a portion corresponding to a portion where switching of the binary signal is paused based on the phase of the AC voltage indicated by the signal from the AC voltage phase detector 201, The extracted chopping pause phase width may be set as the chopping pause phase width θw _OFF .

As described above, even when the rectifier circuit device of the second embodiment has the configuration shown in FIG. 2B, it has the same function and effect as the configuration shown in FIG. 2A described above.

Further, when the configuration shown in FIG. 2C described above is applied, the chopping phase width detector 212 is outputted from the current detector 103 during the chopping pause phase width during the period in which the polarity is fixed and during the measurement period. Chopping pause phase width in which the actual current value Iac is maximum is extracted from the continuous plural measurement results in association with the maximum value (instantaneous value) of the actual current value Iac. The width may be a chopping pause phase width θw _OFF .

The maximum value (instantaneous value) of the actual current value Iac is linked and stored for use because the power supply harmonic level is proportional to the input current, and focusing on the current waveform where the power supply harmonic level becomes the largest, the chopping phase width To control the power supply harmonics below the target level.

Further, in the case where the configuration shown in FIG. 2D is applied, the chopping phase width detector 212 is outputted from the DC voltage detector 110 during the chopping pause phase width during the period in which the polarity is fixed and the measurement period. Chopping pause phase width with the minimum DC voltage Vdc is extracted from a plurality of continuous measurement results in association with the minimum value of the DC voltage Vdc, and the extracted chopping pause phase width is the chopping pause phase width θw _OFF And

The level of power supply harmonics is proportional to the input current. If this relationship is replaced with the DC voltage Vdc, the voltage drop of the DC voltage Vdc becomes large at the place where the load is the largest. Therefore, in the configuration shown in FIG. 2D, the power harmonics are targeted by storing them in association with the minimum value of DC voltage Vdc, focusing on the current waveform where the power harmonics level becomes the largest, and controlling the chopping phase width. It can be controlled below the level.

As described above, when the rectifier circuit device according to the second embodiment has the configuration shown in FIGS. 2B to 2D, even if the load 4 has a characteristic with pulsation, it is excellent as in the configuration shown in FIG. 2A. It has an effect.

Third Embodiment
Hereinafter, a rectifier circuit device according to a third embodiment of the present invention and a control device in the rectifier circuit device will be described.

The rectifier circuit device of the third embodiment according to the present invention is a simplification of the control method of the rectifier circuit device of the first embodiment described above. Chopping phase width detector 212 in the rectifier circuit device according to the third embodiment is a section (positive value) in which the polarity (sign) of AC voltage does not change and is fixed from 0 degrees or 180 degrees until chopping is stopped. The phase width θ1w _ON (chopping phase width) of the first half in the section or negative section) is detected, and the chopping control is performed using the phase width θ1w _ON .

Therefore, the configurations of the rectifier circuit device and the control device of the third embodiment according to the present invention are substantially the same as the configurations of FIG. 1 and FIG. 2A described in the first embodiment, The third embodiment will be described using the same reference numerals as in the first embodiment.

FIG. 6A is a diagram for explaining the control operation according to the fifth operation example of the control device in the rectifier circuit device of the embodiment 3 of the present invention, and (a) AC voltage and DC voltage after rectification FIG. 7 is a signal waveform diagram showing the relationship of (b) a target current waveform to be controlled, and (c) an AC current after actual control. FIG. 6B is a diagram for explaining the control operation according to the sixth operation example of the control device in the rectifier circuit device of the third embodiment of the present invention, and (a) after rectification with AC voltage; It is a signal waveform diagram which shows the relationship with DC voltage, (b) target current waveform to be controlled, and (c) AC current after actual control.

In the fifth operation example of FIG. 6A, the output DC voltage is relatively low, and the phase width θ1w _ON at which the semiconductor switch 104 is chopped is relatively small. On the other hand, in the sixth operation example of FIG. 6B, the output DC voltage is higher than that in the fifth operation example, and the phase width θ1w _{ON at} which the semiconductor switch 104 is chopped is higher than that in the fifth operation example. It is the case of getting bigger.

In the rectifier circuit device of the third embodiment, the phase width θ1w _ON where chopping of the first half is performed in the half cycle period of the AC voltage in the operation example shown in FIGS. 6A and 6B corresponds to FIG. 4A and FIG. Since there is a tendency similar to the tendency shown in, it is possible to obtain the same effect as that of the first embodiment.

Embodiment 4
Hereinafter, a rectifier circuit device of a fourth embodiment according to the present invention and a control device in the rectifier circuit device will be described.

The rectifier circuit device of the fourth embodiment according to the present invention is a simplification of the control method in the rectifier circuit device of the first embodiment, similarly to the rectifier circuit device of the third embodiment described above. The chopping phase width detector 212 in the rectifier circuit device according to the fourth embodiment is a section (positive value) in which the polarity (sign) of the AC voltage does not change and is fixed from 0 degrees or 180 degrees until chopping stops. The chopping control is performed by detecting the second half phase width θ2w _ON in the section or the negative section).

Therefore, the configuration of the rectifier circuit device and the control device of the fourth embodiment according to the present invention is substantially the same as the configuration of FIG. 1 and FIG. 2A described in the first embodiment, The fourth embodiment will be described using the same reference numerals as the reference numerals in the first embodiment.

FIG. 7A is a diagram for explaining a control operation according to a seventh operation example of the control device in the rectifier circuit device of the fourth embodiment of the present invention, and (a) AC voltage and DC voltage after rectification FIG. 7 is a signal waveform diagram showing the relationship of (b) a target current waveform to be controlled, and (c) an AC current after actual control. FIG. 7B is a view for explaining the control operation according to the eighth operation example of the control device in the rectifier circuit device of the fourth embodiment of the present invention, and (a) after rectification with AC voltage; It is a signal waveform diagram which shows the relationship with DC voltage, (b) target current waveform to be controlled, and (c) AC current after actual control.

In the seventh operation example of FIG. 7A, the output DC voltage is relatively low, and the phase width θ2w _ON (chopping phase width) at which the semiconductor switch 104 is chopping is relatively small. On the other hand, in the eighth operation example of FIG. 7B, the output DC voltage is higher than that in the seventh operation example, and the phase width θ2w _{ON at} which the semiconductor switch 104 is chopped is higher than that in the seventh operation example. It is the case of getting bigger.

In the rectifier circuit device of the fourth embodiment, the phase width θ2w _{ON in} which chopping in the second half is performed in the half cycle section of the AC power supply 1 in the operation example shown in FIGS. 7A and 7B corresponds to FIG. Since there is a tendency similar to the tendency shown in 4B, the same function and effect as those of Embodiment 1 can be obtained.

Fifth Embodiment
Hereinafter, a rectifier circuit device of a fifth embodiment according to the present invention and a control device in the rectifier circuit device will be described.

Rectifier circuit device of Embodiment 5 according to the present invention, the chopping phase width Shitadaburyu1 _ON in the rectifier circuit device of the third embodiment described above, the sum of the chopping phase width Shitadaburyu2 _ON in the rectifier circuit of the fourth embodiment The phase width (θw1 _ON + θw2 _ON ) is detected by the chopping phase width detector 212, and the DC voltage is controlled so that the total phase width (θw1 _ON + θw2 _ON ) becomes a desired phase width.

FIG. 8A is a diagram for explaining the control operation according to the ninth operation example of the control device in the rectifier circuit device of the fifth embodiment of the present invention, and (a) AC voltage and DC voltage after rectification; FIG. 7 is a signal waveform diagram showing the relationship of (b) a target current waveform to be controlled, and (c) an AC current after actual control. FIG. 8B is a diagram for explaining a control operation according to a tenth operation example of the control device in the rectifier circuit device of the fifth embodiment of the present invention, and (a) after the rectification with the AC voltage; It is a signal waveform diagram which shows the relationship with DC voltage, (b) target current waveform to be controlled, and (c) AC current after actual control.

In a ninth operation example in FIG. 8A, DC voltage output is relatively low, the chopping phase width Shita1w ON of the first half of the semiconductor switch 104 is _chopped, and the second half of the chopping phase width Shita2w _ON is relatively small That's the case. On the other hand, in the tenth operation example of FIG. 8B, the output DC voltage is high compared to the ninth operation example, and the first half chopping phase width θ1w _ON where the semiconductor switch 104 is chopping, and the second half chopping phase width In this case, θ2w _ON is larger than that in the ninth operation example.

The rectifier circuit device of the fifth embodiment, the half cycle of the period of the AC power supply 1 in the operation example shown in FIGS. 8A and 8B, the first half of the chopping phase width Shita1w _ON, and the second half of the chopping phase width Shita2w _ON is above Since there is a tendency similar to the tendency shown in FIGS. 4A and 4B, the same function and effect as those of Embodiment 1 to Embodiment 4 can be obtained.

Sixth Embodiment
Hereinafter, a rectifier circuit device according to a sixth embodiment of the present invention and a control device in the rectifier circuit device will be described.

FIG. 9A is a diagram for explaining a control operation according to an eleventh operation example of the control device in the rectifier circuit device of the sixth embodiment of the present invention, and (a) AC voltage and DC voltage after rectification FIG. 7 is a signal waveform diagram showing the relationship of (b) a target current waveform to be controlled, and (c) an AC current after actual control. FIG. 9B is a diagram for explaining the control operation according to a twelfth operation example of the control device in the rectifier circuit device of the sixth embodiment of the present invention, and (a) after rectification with AC voltage; It is a signal waveform diagram which shows the relationship with DC voltage, (b) target current waveform to be controlled, and (c) AC current after actual control.

The control device in the rectifier circuit device of the sixth embodiment is characterized in that the circuit loss can be further reduced by setting the target current waveform to a waveform other than a sine wave, for example, a triangular wave. In particular, when the load is light, even if the waveform distortion increases, the harmonic current itself is small, so it is possible to further reduce the circuit loss.

The eleventh operation example of FIG. 9A is a case where the output DC voltage is relatively low, and the phase width θw _ON at which the semiconductor switch 104 is chopped is smaller than the desired phase width θw _ON ^* . Also at this time, since the phase period in which the AC voltage is higher than the DC voltage increases, the current flowing from the AC power supply 1 to the DC side via the reactor 102 and the diode bridge circuit 105 increases. Therefore, the waveform of the AC current is sharpened, and the harmonic component of the AC current is increased.

On the other hand, in the twelfth operation example of FIG. 9B, the output DC voltage is higher than in the eleventh operation example, and the phase width θw _ON at which the semiconductor switch 104 is chopped is higher than the desired phase width θw _ON ^* It is the case of getting bigger. At this time, since the phase period in which the AC voltage is higher than the DC voltage decreases, the AC current flowing from the AC power supply 1 to the DC side via the reactor 102 and the diode bridge circuit 105 decreases, and harmonic components of the AC current Decrease. However, in the twelfth operation example of FIG. 9B, as in FIGS. 4A and 4B, a period (phase width) in which the chopping of the semiconductor switch 104 is performed as compared with the waveform of the eleventh operation example of FIG. The loss of the circuit will increase because

In Embodiment 6, preferably, as shown in FIGS. 9A and 9B, the absolute value of the instantaneous value of the target current waveform is 0 degrees (start point) to 180 degrees (end point) of the AC voltage with the passage of time. In the first half of the period up to the end of the period, after a monotonously increasing with a constant slope, it is monotonically decreasing with a constant slope from a predetermined midpoint (an angle smaller than 90 degrees) Use a waveform.

9A and 9B, since one chopping phase width θw _ON is illustrated in a half cycle of the AC voltage, two chopping pause phase widths are illustrated in one cycle of the AC voltage. Therefore, as described above, chopping control may be performed based on the phase width of any of the two chopping pause phase widths, or the total phase width. Alternatively, as described in the second embodiment, the chopping phase width θw _ON is subtracted from the half cycle of the AC voltage to obtain the chopping pause phase width θw _OFF . Alternatively, control may be performed based on the obtained chopping pause phase width θw _OFF by directly obtaining the chopping pause phase width θw _OFF .

(Modification of Embodiment 6)
Hereinafter, modifications of the rectifier circuit device and the control device according to the sixth embodiment of the present invention will be described with reference to FIGS. 10A to 10D. The modification of the sixth embodiment according to the present invention has another shape different from the target current waveform shown in FIGS. 9A and 9B.

FIG. 10A is a diagram for illustrating a control operation according to a thirteenth operation example of the control device in the rectifier circuit device of the sixth embodiment of the present invention, and (a) AC voltage and DC voltage after rectification FIG. 7 is a signal waveform diagram showing the relationship of (b) a target current waveform to be controlled, and (c) an AC current after actual control. FIG. 10B is a diagram for explaining the control operation according to the fourteenth operation example of the control device in the rectifier circuit device of the sixth embodiment of the present invention, It is a signal waveform diagram which shows the relationship with DC voltage, (b) target current waveform to be controlled, and (c) AC current after actual control. Furthermore, FIG. 10C is a diagram for explaining a control operation according to a fifteenth operation example of the control device in the rectifier circuit device of the sixth embodiment of the present invention, and (a) after rectification with AC voltage. It is a signal waveform diagram which shows the relationship with DC voltage, (b) target current waveform to be controlled, and (c) AC current after actual control. Further, FIG. 10D is a diagram for explaining a control operation according to a sixteenth operation example of the control device in the rectifier circuit device of the sixth embodiment of the present invention, and (a) after the rectification with the AC voltage. It is a signal waveform diagram which shows the relationship with DC voltage, (b) target current waveform to be controlled, and (c) AC current after actual control.

As compared with the target current waveform in the eleventh operation example of FIG. 9A, the target current waveform in the thirteenth operation example of FIG. 10A is a predetermined value exceeding 90 degrees in the latter half, instead of a monotonically decreasing section with time. It is a triangular waveform configured to have a section (zero and constant section) which is instantaneously zeroed at the midpoint Tm of the phase (for example, 110 degrees).

Further, the target current waveform in the fourteenth operation example of FIG. 10B is sinusoidally increased in a monotonously increasing section with time as compared with the target current waveform in the thirteenth operation example of FIG. The waveform has a section (zero and constant section) which is instantaneously zero at a midpoint Tm of a predetermined phase (for example, 110 degrees) exceeding 90 degrees.

Furthermore, the target current waveform in the fifteenth operation example of FIG. 10C provides a constraint condition in the target current waveform in the fourteenth operation example of FIG. 10B, and the midpoint Tm before 90 degrees in the first half sine wave waveform. The waveform is instantaneously zeroed at a phase of (for example, 70 degrees).

Further, the target current waveform in the sixteenth operation example of FIG. 10D is zero (zero) for a predetermined period from 0 degrees to the first midpoint Tm1 over time in the target current waveform in the fifteenth operation example of FIG. And a constant interval), and thereafter, it is a waveform configured to monotonously increase up to the second midpoint Tm2.

In the operation example of FIG. 10C and FIG. 10D, the target current is set to zero before 90 degrees, but the chopping operation of the semiconductor switch 104 is before chopping operation before the phase to be zeroed. You can use it with a heavy load. Moreover, in this operation example, since the DC voltage is lower than the maximum instantaneous voltage of the AC voltage, current flows from the AC power supply 1 via the reactor 102 and the diode bridge circuit 105 in the vicinity of 90 degrees. Therefore, even if the target current is zero, the AC current continues to flow for a while, and a current with few harmonic components can be realized with high efficiency.

In each of the above embodiments, the monotonous increase or decrease of the target current waveform may include a fixed period, that is, it may be substantially monotonically increased or substantially monotonically decreased. Here, “substantially monotonically increasing” refers to a monotonous increase in a broad sense having a relationship of f (θ1) ≦ f (θ2) when the phase θ1 <θ2 of the target current waveform. Over time, substantially monotonically increasing so as to at least increase or at least increase and be constant over a period. Also, “substantially monotonically decreasing” refers to a monotonous decrease in a broad sense in which f (θ1) ≧ f (θ2) when the phase θ1 <θ2 of the target current waveform. And substantially monotonically decreasing so as to at least decrease or at least decrease and be constant over a period of time.

Seventh Embodiment
Hereinafter, a rectifier circuit device according to a seventh embodiment of the present invention and a control device in the rectifier circuit device will be described.

FIG. 11 is a circuit diagram showing a configuration of a rectifier circuit device according to a seventh embodiment of the present invention. In the rectifier circuit device of the seventh embodiment, the AC voltage from AC power supply 1 is rectified by a bridge circuit constituted of

semiconductor switches

604a and 604b and

diodes

605a, 605b, 605c and 605d via reactor 602, The load 4 is driven via the smoothing capacitor 106.

The chopping control method in the rectifier circuit device of the seventh embodiment is the same as that of the control device in the rectifier circuit device of the first embodiment shown in FIG. 1 described above, and chopping drive signals for two

semiconductor switches

604a and 604b. It drives simultaneously using Sch.

The chopping drive signal Sch in the rectifier circuit device of the seventh embodiment can be formed with the same configuration as that described with reference to FIGS. 2A to 2E in the first embodiment. Also in the rectifier circuit device of the seventh embodiment, similar effects can be obtained by performing the chopping control described in each of the above-described embodiments.

Eighth Embodiment
Hereinafter, a rectifier circuit device according to an eighth embodiment of the present invention and a control device in the rectifier circuit device will be described.

FIG. 12 is a circuit diagram showing a configuration of a rectifier circuit device according to an eighth embodiment of the present invention. The rectifier circuit device according to the eighth embodiment rectifies AC voltage from AC power supply 1 with a bridge circuit configured of

semiconductor switches

704a and 704b and

diodes

705a, 705b, 705c and 705d via reactor 702. , Drive the load 4 via the smoothing capacitor 106.

According to the chopping control method in the rectifier circuit device of the eighth embodiment, only one of the

semiconductor switches

704a or 704b is selected using two chopping drive signals Sch1 and Sch2 according to the polarity of the AC voltage from AC power supply 1. It is what makes chopping work. For example, if the period in which the polarity of the AC voltage is connected to the reactor 702 is high, the chopping drive signal Sch2 is used to chopping the semiconductor switch 704b and the polarity of the AC voltage is connected to the reactor 702 is low If it is a period, the chopping drive signal Sch1 is used to chopping the semiconductor switch 704a.

In the rectifier circuit device according to the eighth embodiment, when the semiconductor switches 704 a and 704 b are simultaneously turned on, the DC output voltage to the load 4 is short-circuited. It may be necessary to set so that neither switch 704a nor 704b will be in an ON state. When set in this manner, in FIGS. 4A and 4B described above, the phase in which the chopping operation changes to the pause state can occur even near 0 degrees and 180 degrees. However, in this case, the chopping operation is intentionally stopped to prevent a short circuit of the DC output voltage, so in the rectifier circuit device according to the eighth embodiment of the present invention, the chopping operation is performed near 0 degrees and 180 degrees. This can be easily realized by not handling the phase changed to the resting state.

The chopping drive signals Sch1 and Sch2 in the rectifier circuit device of the eighth embodiment can be formed with the same configuration as that described with reference to FIGS. 2A to 2E in the first embodiment described above. Also in the rectifier circuit device of the eighth embodiment, the same operation and effect can be achieved by performing the chopping control described in each of the above-described embodiments for each semiconductor switch.

(Embodiment 9)
Hereinafter, a rectifier circuit device according to a ninth embodiment of the present invention and a control device in the rectifier circuit device will be described.

FIG. 13 is a circuit diagram showing a configuration of a rectifier circuit device according to a ninth embodiment of the present invention. In the rectifier circuit device according to the ninth embodiment, when the semiconductor switch 104 is on via the rectifier bridge 105 and the reactor 102 at both output terminals of the AC power supply 1, the reactor 102 is charged with current, and the semiconductor switch 104 is off. When it becomes, the smoothing capacitor 106 and the load 4 are driven by the diode 304.

The chopping drive signal Sch in the rectifier circuit device of the ninth embodiment can be formed with the same configuration as the configuration described using FIG. 2A to FIG. 2E in the first embodiment described above. Also in the rectifier circuit device of the ninth embodiment, similar effects can be obtained by performing the chopping control described in each of the above-described embodiments for each semiconductor switch.

The binarization processing of the voltage level comparator 109 used in the rectifier circuit device according to the first to ninth embodiments of the present invention will be described below with reference to FIGS. 14A and 14B.

FIG. 14A is a waveform diagram for describing a first operation example of the binarization processing of the voltage level comparator 109 in the rectifier circuit device according to the first to ninth embodiments of the present invention. The waveform diagram of FIG. 14A shows (a) the relationship between the AC voltage and the threshold voltage Vth and (b) the binary signal from the voltage level comparator 109. FIG. 14B is a waveform diagram for describing a second operation example of the binarization processing of the voltage level comparator 109 in the rectifier circuit device according to the first to ninth embodiments of the present invention. The waveform chart of FIG. 14B shows (a) the relationship between the AC voltage and the threshold voltage Vth and (b) the binary signal from the voltage level comparator 109.

FIGS. 14A and 14B show a method of detecting a voltage phase from information on whether the AC voltage is equal to or higher than a certain level. This information is used to obtain, as a binary signal, whether the instantaneous voltage of the AC voltage exceeds a threshold. That is, the voltage level comparator 109 compares the AC voltage with the threshold voltage Vth, and outputs a high level signal when the AC voltage is higher than the threshold voltage Vth, while the AC voltage is lower than the threshold voltage Vth. When low level signal is output.

Here, even if the threshold voltage Vth fluctuates, the cycle of the binary signal is the same as the power supply frequency, and if the middle point of the high level side or the low level side of the binary signal is determined, the AC voltage phase is 90 degrees. Or you can know the time of 270 degrees. Also, the midpoint of the AC voltage phase of 90 degrees and 270 degrees is 180 degrees and 0 degrees of phase. If the information obtained in this manner is multiplied using a PLL or the like, it is possible to accurately know the instantaneous phase.

For example, if it is multiplied by 360, one pulse corresponds to one degree, and if this pulse is counted, phase information whose unit is degree can be obtained. Then, based on the obtained phase information, the instantaneous target current waveform may be recalled. About the method of detecting a phase using the binary information obtained from other level comparisons, for example, it is proposed also to patent documents 4 which the present inventor indicated, and it is not limited in particular.

As described above, in the rectifier circuit devices according to the first to ninth embodiments of the present invention, even if there is an error in the DC voltage detection accuracy, the phase width during chopping operation becomes a desired phase width. To adjust the DC voltage relatively. Therefore, in the rectifier circuit devices of Embodiments 1 to 9 according to the present invention, the same current waveform is obtained, and it is possible to realize the rectification operation with less circuit loss and less harmonic current.

Tenth Embodiment
The rectifier circuit device according to the tenth embodiment of the present invention and the control circuit for the rectifier circuit device will be described below.

FIG. 15 is a block diagram showing a detailed configuration of the control circuit 100 in the rectifier circuit device of the tenth embodiment according to the present invention. The control circuit 100 in the rectifier circuit device of the tenth embodiment is between the DC voltage detector 110 and the subtractor 206 in comparison with the control circuit 100 in the rectifier circuit device of the first embodiment shown in FIG. 2A described above. , And an AD converter 230 which is an AD conversion unit, and a low pass filter operation unit (hereinafter referred to as “LPF operation unit”) 231 which is an operation unit. The rectifier circuit device of the tenth embodiment provides an embodiment that is particularly effective when implemented by digital operation. Hereinafter, differences from the control circuit 100 shown in FIG. 2A will be described.

In FIG. 15, an analog signal indicating the DC voltage Vdc detected by the DC voltage detector 110 indicates an AD conversion value Vad by the AD converter 230 that AD converts at a sampling frequency sufficiently higher than the frequency of the AC power supply 1. It is converted to a digital signal. The AD conversion value Vad from the AD converter 230 is input to the LPF computing unit 231 that performs computation (details will be described later) having low-pass filter characteristics, and is subjected to LPF computation. A signal (LPF calculation value Vdca) indicating the calculation result in the LPF calculator 231 is output to the subtractor 206. In the rectifier circuit device of the tenth embodiment, for example, the frequency of the AC power supply 1 is 60 Hz, and the sampling frequency is 600 kHz.

FIG. 16 is a block diagram showing a detailed configuration of the LPF computing unit 231 in the control circuit 100 shown in FIG. In FIG. 16, the signal indicating the AD conversion value Vad from the AD converter 230 is input to the adder 253 in the LPF computing unit 231. The adder 253 adds the signal indicating the AD conversion value Vad to be input and the signal from the constant multiplier 251, and outputs a signal indicating the LPF operation value Vdca which is the addition result to the subtractor 206. The signal is output to the constant multiplier 251 via the delay unit 252 delayed by one clock time. The constant multiplier 251 multiplies the input signal by a predetermined constant (2 ⁿ -1) / (2 ⁿ ), and outputs a signal indicating the multiplication result to the adder 253.

Assuming that the operation by the LPF computing unit 231 shown in FIG. 16 is X (j) as an input and Y (j) as an output, and expressed as a time-series recurrence formula, the following equation (1) is obtained.

Y (j + 1) ← [(2 ⁿ -1) / (2 ⁿ )] × Y (j) + X (j) (1)

This LPF calculation processing is a linear low-pass filter having a time constant of “2 ⁿ ” times the calculation cycle, and the amplitude is “2 ⁿ ” times. Therefore, by executing this LPF calculation process, n bits of information after the decimal point are added to the AD conversion value Vad.

FIG. 17 is a signal waveform diagram representing an operation of control circuit 100 in the rectifier circuit device shown in FIG. In the signal waveform diagram of FIG. 17, (a) AC current Iac from AC power supply 1, (b) DC voltage Vdc, and (c) AD conversion value Vad of AD converter 230 are shown. In (c) of FIG. 17, the DC voltage Vdc is indicated by a dotted line. That is, FIG. 17 shows an operation principle capable of improving voltage detection accuracy by performing low-pass filter processing with a single-phase AC rectifier circuit.

Since the AC voltage from single-phase AC power supply 1 has a section of zero and the instantaneous power is not constant, DC voltage still has a fluctuation having a frequency twice the power supply frequency even if smoothing capacitor 106 is used. . In order to reduce this fluctuation, the capacity of the smoothing capacitor 106 needs to be increased infinitely, which is practically impossible.

(C) in FIG. 17 shows a DC voltage Vdc indicated by a dotted line and an AD conversion value Vad when the DC voltage Vdc is AD converted at a sampling frequency sufficiently higher than the frequency of the AC power supply 1. Here, a sufficiently high sampling frequency means a frequency twice or more that of the AC power supply 1. According to the instantaneous DC voltage Vdc, the obtained AD conversion value Vad (digital value) takes values of K, K + 1, K + 2, K + 3,. Here, when the low-pass filter calculation is performed on the AD conversion value Vad, in the case of FIG. 17, the value converges to a value between (K + 1) and (K + 2). Furthermore, as shown in FIG. 16, since it includes a function of multiplying by 2 ⁿ as a low-pass filter operation, a value between {(K + 1) × 2 ⁿ } and {(K + 2) × 2 ⁿ } Integer value is obtained. That is, n bits of information after the decimal point is added to the resolution of the AD converter 230 to improve the resolution. In the case where there is no fluctuation in the DC voltage Vdc having a frequency twice as high as the power supply frequency, such as the average value of (c) in FIG. 17, the AD conversion value Vad always becomes (K + 1) However, the resolution can not be improved. That is, the method (low-pass filter processing) of the LPF calculation can exhibit its effect by the single-phase AC rectifier circuit device.

(Modified example and supplementary description of the tenth embodiment)
In the subtractor 206 in the rectifier circuit device of the first embodiment shown in FIG. 2A described above, the command voltage Vdc ^* also needs to have the same resolution as that of the AD converter 230. Since command voltage Vdc ^* is only information, it is possible to easily realize an increase in resolution as in the above-described tenth embodiment.

Also, although the LPF operation has been described as an example using a power of 2, if the constant of the constant multiplier 251 is set to a value between 0 and 1, the LPF operation can be realized similarly. Further, as is clear from the operation principle of FIG. 17, similar effects can be obtained by methods other than the configuration shown in FIG.

In the configuration of the rectifier circuit device of the tenth embodiment, fine voltage information can be obtained even when the resolution of AD converter 230 is coarse, so that DC voltage Vdc can be adjusted with high precision, and circuit loss can always be achieved. Can realize a rectification operation with a small number of harmonic currents and a small number of harmonic currents.

Further, the method for improving the voltage detection accuracy in the rectifier circuit device of the tenth embodiment can be implemented in combination with the first to ninth embodiments described above.

In each of the embodiments according to the present invention, the term "substantially" is used to mean approximately or on average.

In the control circuit and the rectifier circuit device of the rectifier circuit device according to the present invention, as apparent from the above embodiments, even if there is an error in the detection accuracy of the DC voltage, the DC voltage is adjusted to a relatively appropriate value. Thus, the same current waveform can be obtained, and the desired phase width can be changed in accordance with the load condition or an external command. Further, according to the present invention, circuit loss is always reduced and harmonic current is constantly measured by accurately measuring the chopping operation phase width or chopping pause phase width to be compared with the desired phase width regardless of the load fluctuation state. Can realize a rectification operation with less

Further, in the present invention, the DC voltage is converted into a digital signal by the A / D conversion unit and detected at a sampling frequency sufficiently higher than the frequency of the AC power supply, and the obtained digital signal is subjected to LPF calculation for each cycle. Then, it is added to the digital signal so as to interpolate minute information below the resolution. Furthermore, in the present invention, a digital signal obtained by interpolating minute information is used as DC voltage information, and the digital signal obtained by interpolating the minute information is adjusted so that the phase width actually being chopping becomes a desired value. . According to the present invention, according to the present invention, the power supply frequency component contained in the smoothed voltage of the DC voltage has fluctuations, and even if the resolution of the digital information is coarse, the digital signals are dispersed by the fluctuations. It is possible to obtain a digital signal equivalent to By this, in the present invention, even if coarse resolution AD conversion means are used, the average value of DC voltage can be adjusted with high accuracy, and a rectification operation with less loss and less harmonic current is always realized. can do. Therefore, the rectifier circuit device according to the present invention can realize the rectification operation with less loss and less harmonic current by changing the desired phase width according to the state of the connected load.

As common to all the embodiments in the present invention, when chopping changes from the paused state to the chopping state, it may change to the paused state only for a moment due to the fluctuation or noise of the circuit. In such a case, the configuration of the rectifier circuit device and the control circuit of the present invention can be easily realized by not treating the chopping in the present invention as a phase changed to the inactive state.

Furthermore, in the embodiment according to the present invention, the AC voltage phase detector 201 detects the phase of the AC voltage, and the chopping phase width is detected based on the detected phase. It is not limited to such a configuration. For example, as the configuration in the present invention, when the frequency of the AC power supply is fixed, the chopping phase width may be detected based on information such as the zero cross of the AC power supply. In addition, when detecting the chopping phase width, the time of the chopping phase width may be measured by counting by the number of pulses of the carrier signal for realizing the PWM control which is an example of the chopping method.

Although the present invention has been described in the embodiments with a certain degree of detail, the disclosed contents of these embodiments should be changed in the details of the configuration, and the combination and order of the elements in the embodiments can be appropriately changed. Changes can be made without departing from the scope and spirit of the claimed invention.

The rectifier circuit device according to the present invention can achieve both suppression of harmonic current and reduction of circuit loss. Therefore, a heat pump is configured by compressing a refrigerant with a compressor, and cooling, heating, food, etc. It can be widely applied to various applications such as those that perform refrigeration.

Reference Signs List 1 AC power supply 4 load 100

control circuit

102, 602, 702

reactor

103, 112

current detector

104, 604a, 604b, 704a, 704b semiconductor switch 105 diode bridge circuit 106 smoothing capacitor 109 voltage level comparator 110 DC voltage detector 111 waveform Shaper 201 AC voltage phase detector 202 Target current waveform shaper 203 Target

phase width setter

204, 206, 209 Subtractor 205 Phase width compensation computing unit 207 Vdc compensation computing unit 208 Multiplier 210 Iac compensation computing unit 211 PWM modulator 212 Chopping phase width detector 230 AD converter 231 low pass filter calculator (LPF calculator)
251 constant multiplier 252 delay device 253 adder 605a to 605d, 705a to 705d diode

Claims

The chopping operation of the semiconductor switch shorts or opens the alternating voltage from the single phase alternating current power supply or the pulsating voltage obtained by rectifying the alternating current voltage through the reactor to rectify the single phase alternating current power supply into the direct current voltage. Control device of the rectifier circuit device for supplying power to the load,
The controller is
A waveform forming unit that forms a target current waveform having the same frequency as the waveform of the AC voltage;
An alternating current detection unit that detects an alternating current flowing from the single-phase alternating current power supply;
A DC voltage detection unit that detects the DC voltage;
A first control unit configured to control a chopping operation of the semiconductor switch such that a waveform of the detected alternating current substantially becomes the target current waveform;
A second control unit configured to control an amplitude of the target current waveform such that the detected DC voltage substantially becomes a predetermined target DC voltage;
The predetermined target DC voltage is controlled such that a chopping operation phase width in which the semiconductor switch is in a chopping operation state or a chopping pause phase width in which the semiconductor switch is in a chopping pause state is substantially a predetermined phase width. 3 controls,
A control device for a rectifier circuit device, comprising:
The rectifier according to claim 1, wherein the predetermined phase width is changed and set in a range of 0 degree to 180 degrees with respect to a power supply half cycle according to a load condition or an external command. Control device of circuit device.
The control device for a rectifier circuit device according to claim 2, wherein the status of the load is configured to be indicated by the value of the AC current, the input power calculated based on the AC current, or the output power of the rectifier circuit device. .
In the third control unit, an instantaneous value of the chopping pause phase width or chopping operation phase width detected within a period in which the polarity of the alternating voltage is fixed, or an average value by a preset number of times is substantially The control device of the rectifier circuit device according to any one of claims 1 to 3, configured to control the predetermined target DC voltage so that the predetermined phase width is achieved.
In the third control unit, the chopping pause phase width or chopping operation phase width detected in a period in which the polarity of the AC voltage is fixed, including the lowest DC voltage in a predetermined period, is substantially The control device of the rectifier circuit device according to any one of claims 1 to 3, configured to control the predetermined target DC voltage so that the predetermined phase width is achieved.
The third control unit is configured such that a chopping pause phase width or chopping operation phase width detected within a period in which the polarity of the AC voltage is fixed, including the largest AC current in a predetermined period, is substantially The control device for a rectifier circuit device according to any one of claims 1 to 3, configured to control the predetermined target DC voltage so as to have a predetermined phase width.
When a plurality of the chopping operation phase widths or a plurality of the chopping pause phase widths exist in a period in which the polarity of the alternating voltage is fixed, the third control unit is in any of the periods. The rectifier circuit device according to any one of claims 1 to 6, which is configured to control the predetermined target DC voltage so that the phase width of or the total phase width is substantially equal to the predetermined phase width. Control device.
In the target current waveform, in the period in which the instantaneous absolute value of the target current waveform is fixed in the polarity of the AC voltage, (a) time elapses from the start point of the period to the predetermined middle point And at least increase, or at least increase, and substantially monotonously increase so as to be constant over a period, and (b) at least decrease from the midpoint to the end over time, or The rectifier circuit device according to any one of claims 1 to 7, wherein it is set to have a period which becomes at least decreasing and then substantially monotonically decreasing so as to be constant for part of the period and then becomes zero. Control device.
The target current waveform is (a) from the start point of the period to a predetermined first intermediate point within a period in which the absolute value of the instantaneous value of the target current waveform is fixed in polarity of the AC voltage. (B) at least increasing or at least increasing from the first intermediate point to a predetermined second intermediate point, and constant over a period of time, (C) substantially substantially monotonically increasing, and (c) at least decreasing or at least decreasing with the passage of time from the second intermediate point to the end point, and being constant for a part period The control device of the rectifier circuit device according to any one of claims 1 to 7, wherein the control device is set to have a period which becomes zero after being monotonically decreased.
It further comprises a phase detection unit that generates a binary signal by comparing the AC voltage with a predetermined threshold voltage,
The waveform forming unit detects a cycle and a phase of the AC voltage based on the binary signal, and a target current waveform having the same frequency as the waveform of the AC voltage based on the cycle and the phase of the detected AC voltage. Form
The third control unit is configured to detect a chopping operation phase width in which the semiconductor switch is in the chopping operation state or a chopping pause phase width in which the semiconductor switch is in the chopping suspension state based on the binary signal. A control device of a rectifier circuit device according to any one of claims 1 to 9.
The control device is further provided between the direct current voltage detection unit and the second control unit, and includes an AD conversion unit that AD-converts the detected direct current voltage into a digital voltage, the AD conversion unit, and An arithmetic unit which is provided between the second control unit and the second control unit, and after performing low-pass filter operation on the digital voltage, outputs the voltage of the operation result to the second control unit as the detected DC voltage The control apparatus of the rectifier circuit apparatus as described in any one of the Claims 1 thru | or 10 provided with these.
The control device of a rectifier circuit device according to claim 11, wherein a sampling frequency of the AD conversion unit is set to be sufficiently higher than a frequency of the single phase AC power supply.
The low-pass filter calculation multiplies the immediately preceding calculation result by a coefficient (“ n ” is an integer) “(2 n −1) / (2 n )”, and then adds the result to the input digital voltage The control device of the rectifier circuit device according to claim 11 or 12, configured to be executed using the value of the addition result as the next calculation result.
A rectifier circuit device comprising the control device of the rectifier circuit device according to any one of claims 1 to 13.