JPH0888972A - Power supply - Google Patents

Abstract

PURPOSE: To provide a power supply whose stability at start of operation or stoppage is enough, and which has a high accuracy and besides a high-speed controllability at stationary time, though this is equipped with an active filter. CONSTITUTION: In a power supply, which is equipped with an active filter 10 for removing the AC component between a thyristor converter 1 and an electromagnet 3 to serve as load, a detector 12, which detects the state of the active filter 10, and a selector 13, which controls the gain of a feedback system, by the detection result of this detector 12, are provided. Accordingly, the gain of the whole control system is controlled, according to the state of the active filter 10, and at start of operation or at stoppage or when the output of the active filter 10 becomes excessive, it operates stably under low gain, and at stationary operation, high accuracy and high controllability can be given with high gain.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a direct-current power supply device, and more particularly to a power supply device suitable for exciting a main electromagnet of a particle accelerator that needs to be controlled with high accuracy and high response.

[0002]

2. Description of the Related Art As is well known, in particle accelerators such as synchrotrons, the orbit of elementary particles is controlled by the strength of a magnetic field, and therefore a strong electromagnet is used. Then, a power supply device for exciting such an electromagnet is required to rapidly change the load current in a predetermined pattern under high power and repeatedly control the load current.
Therefore, high precision and high speed control response are required.

Therefore, conventionally, for example, Japanese Unexamined Patent Publication No. 4-355 has been proposed.
As disclosed in Japanese Patent No. 667, a deviation between a current setting value (current command value) and a load current detection value is set as a voltage setting value,
A current control system that controls so that the deviation between this voltage setting value and the detected value of the DC output voltage of the AC / DC converter converges to zero,
Power supplies with active filters have been used.

According to this conventional technique, the current control system also includes the characteristics of the load, and the sufficiently smoothed direct current is supplied to the load, so that the gain of the current control system is sufficiently increased. As a result, the response to the current command value is speeded up, and high control accuracy can be easily obtained.

[0005]

The above-mentioned prior art does not consider the operation of the control system due to the use of the active filter, and has a problem in stability as described below. .

First, in the prior art, the response to the command value can be speeded up by increasing the gain of the current control system, but on the other hand, at the start and stop of the operation in which the current is intermittent, the active filter Since the output may exceed a predetermined value, it is necessary to put the active filter in the inactive state (OFF) at this time.

However, if an attempt is made to increase the gain of the control system while keeping the active filter inoperative, the control becomes unstable due to the delay of the phase characteristic of the entire control system.

Immediately after the active filter is changed from the inactive state to the active state, the operation of the control system is not stabilized, so that the controllable range of the active filter may be exceeded. At this time, if the control gain is increased, this also becomes a destabilizing factor. Furthermore, even when the active filter has an excessive output due to a sudden change in the power supply voltage, etc., even when the operation is not started or stopped, the operation of the active filter is hindered. It becomes unstable. Therefore, the conventional technique still has a problem in terms of stabilizing the operation.

According to the present invention, in a power supply device equipped with an active filter, the gain of the control system needs to be increased in order to obtain a high-precision and high-speed control response when a steady operation command is issued, whereas the operation start, This is done in view of the fact that it is necessary to reduce the gain of the control system when an operation command such as stop is issued or when the active filter is in an excessive output state, and conflicting conditions are required. An object of the invention is to provide a power supply device which can always obtain a highly accurate and stable high-speed control responsiveness in any operating condition.

[0010]

The above object is to provide an AC / DC converting means for converting AC into DC and outputting the same, a current control means for generating and outputting an output voltage command of the AC / DC converting means, and the AC / DC converting means. Voltage control means for generating and outputting the ignition phase angle command, control means for controlling the output of the AC / DC converting means based on the ignition phase angle command, and the output voltage command from the output voltage of the AC / DC converting means. And an active filter for detecting a pulsating component of the output voltage of the AC / DC converting means, generating a voltage having a phase opposite to the pulsating component and superimposing it on the signal on the output side of the AC / DC converting means, Detecting means for detecting an operating state of the active filter in a DC power supply configured to supply a current from the AC / DC converting means to the load via the active filter, and the current according to the detection result of the detecting means. A gain selecting means for selecting the gain of the control system by control means provided, the gain of the control system in accordance with the operating state of the active filter is achieved as controlled.

[0011]

According to the present invention, the control gain of the entire power supply device is
Control is performed according to the state of the active filter, and at the time of operation command such as operation start, stop, etc. and in unstable state such as excessive output of the active filter, it is operated with low control gain, and high speed controllability is required. It operates with a high control gain at the time of steady operation command such as repetitive operation and changes the control gain so as to satisfy the high speed controllability, so the power supply device has high stability and high precision and high speed controllability. Can be realized.

Further, since it is possible to provide a function of comparing the operating state detected by the detecting means with the current command of the current command generating means and a protective interlock function, it is possible to make a finer control gain selection and also to perform the interlocking. Since the lock can be simplified, more stable operation can be obtained,
A power supply device with high accuracy and high speed controllability can be realized.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The power supply device according to the present invention will be described below in detail with reference to the illustrated embodiments. FIG. 1 shows an embodiment in which the present invention is applied to a DC power supply device for supplying an exciting current to an electromagnet of a particle accelerator such as a synchrotron.
In the figure, 1 is a thyristor converter, 2 is a DC filter, 3 is an electromagnet (load), 4 is a current detector, 5 is a current control circuit (ACR), 6 is a voltage control circuit (AVR), and 7 is an automatic pulse transfer. Phaser, 8 and 9 adders, 10 active filters,
Reference numeral 11 is a set value generator, 12 is a detector, and 13 is a selector.

The thyristor converter 1 constitutes an AC / DC converter and functions to convert AC power supplied from a predetermined power system such as a commercial AC power system into DC power. The DC filter 2 is a low-pass filter including a reactor and a capacitor, and functions to smooth the output voltage of the thyristor converter 1. The electromagnet 3 is for generating the magnetic field of the particle accelerator, as described above. The current detector 4 detects the current (load current) i flowing through the electromagnet 3 and supplies it to the subtraction input of the adder 9.

The current control circuit 5 constitutes a current control means,
It functions to generate a voltage setting value u according to a current deviation signal supplied via a selector 13 described later.

The voltage control circuit 6 constitutes a voltage control means,
It functions to generate a voltage control signal according to the voltage deviation signal supplied from the adder 8. The automatic pulse phase shifter 7 operates based on the signal of the voltage control circuit 6 and has a function of generating a pulse for controlling the control angle of each thyristor constituting the thyristor conversion device 1.

The active filter 10 takes in the output voltage v _p of the DC filter 2 and the voltage set value u which is the output of the current control circuit 5, and has a polarity opposite to the AC component remaining in the output of the DC filter 2. By adding the AC component of the above to the output voltage v _p , it works to cancel and remove the AC component. The set value generator 11 constitutes a current command generating means, generates a current set value r for determining the magnitude of the current to be supplied to the electromagnet 3, and supplies it to the addition input of the adder 9. . Therefore, the adder 9 generates a current deviation signal obtained by subtracting the detected value of the load current i from the current setting value r, and supplies this to the selector 13.

The detector 12 serves to detect the state of the active filter 10 and generate a predetermined selection signal. The details of the detected content will be described later. The selector 13 functions to switch the gain of the current deviation signal input from the adder 9 according to the selection signal supplied from the detector 12.

Next, the operation of the embodiment shown in FIG. 1 will be described. The current set value r is added from the set value generator 11 to the adder 9
Then, the current deviation signal is input to the selector 13. The selector 13 is selected by the selection signal supplied from the detector 12 to have an optimum gain corresponding to the state of the active filter 10, and after giving this optimum gain to the input current deviation signal. Input to the current control circuit 5.

In the current control circuit 5, the output voltage of the thyristor converter 1 required to make the deviation between the current setting value r and the load current i zero based on the current deviation signal given the predetermined gain. The command is calculated and output to the adder 8 as the voltage set value u. The adder 8 calculates the deviation between the voltage setting value u and the output voltage v _t of the thyristor converter 1, and the deviation is input to the voltage control circuit 6. Therefore, the voltage control circuit 6 calculates the final firing phase angle command based on the voltage setting value u, and the calculation result is output to the automatic pulse phase shifter 7.

As a result, the automatic pulse phase shifter 7 operates according to the output voltage command of the voltage control circuit 6 and the thyristor converter 1.
Of the output voltage v _t is controlled, and the DC power having the output voltage v _t is input to the DC filter 2, where the pulsating component of the output voltage v _t is reduced and input to the active filter 10.

Therefore, the active filter 10 inputs the output voltage v _p of the DC filter 2 and the voltage setting value u, and has an opposite phase to the AC component contained in the output voltage v _p of the DC filter 2 due to the deviation thereof. Of the direct current filter 2 is operated so as to be superposed on the output voltage v _p of the direct current filter 2, whereby the alternating current component contained in the output voltage v _p of the direct current filter 2 is canceled and output to the electromagnet 3. As a result, a sufficiently smoothed DC voltage is applied to the electromagnet 3.

Next, when a DC voltage is applied to the electromagnet 3 in this way, a current i flows in the exciting coil. Then, this current i is detected by the current detector 4, and its detection output is input to the adder 9. In the adder 9, as described above, the deviation between the current set value r and the detection output of the current detector 4 is calculated. As a result, the exciting current i of the electromagnet 3 is feedback-controlled, and the current i that accurately follows the current set value r supplied from the set value generator 11 can be supplied to the electromagnet 3 in a pattern required for the particle accelerator. The magnetic field can be precisely generated.

At this time, as the gain in the control system is increased, the control response of the load current i with respect to the current setting value r can be increased, but the control gain is increased as described above. If the operation is started by instructing operations such as starting and stopping the operation, the operation becomes unstable.

Therefore, in this embodiment, as described above, the detector 12 and the selector 13 are provided, whereby the state of the active filter 10 is detected, that is, the active filter 10 is operating. Whether or not it is within the controllable range is detected by the detector 12, and when it is in an unstable state such as at the time of operation command for start and stop of operation, this detector 12 is used to select the selector 13. At the time of a normal operation command such as a repetitive operation in which a response is required, the detector 12 to the selector 13
In addition, a signal for increasing the gain is provided.

Even during operation, if the output of the active filter 10 becomes excessive, the operation becomes unstable. Therefore, the detector 12 takes in the output of the active filter 10 and compares it with a preset output upper limit value of the active filter 10, and when the upper limit value is exceeded, the gain is similarly fed to the selector 13. Is configured to provide a signal that lowers.

As described above, the selector 13 determines the gain of the current deviation signal input from the adder 9. Therefore, if the gain of the selector 13 is increased, the control gain of the current control system is increased and the control response is increased. On the contrary, if the gain of the selector 13 is decreased, the control gain is reduced but stability is improved. Will increase.

Therefore, according to this embodiment, in an unstable state that occurs when an operation command is issued such as when the operation is started or stopped, or in an unstable operation state that occurs when the output of the active filter 10 becomes excessive. Thus, it is possible to surely realize a stable power supply device having a control performance capable of lowering and stabilizing the control gain and making a high control gain at the time of a steady operation command such as repetitive operation and capable of high-speed response with high accuracy.

As a result of this, the active filter 1 is further added.
When the output of 0 becomes less than or equal to the upper limit value, this is detected by the detector 12 and a signal for increasing the gain of the selector 13 is provided to configure the active filter 1
It is possible to obtain a power supply device that protects when 0 becomes an excessive output, and can be restarted when it returns to a normal state.

Next, another embodiment of the present invention will be described. FIG. 2 shows another embodiment of the present invention. In FIG.
The same elements as those in the embodiment of FIG. 1 are designated by the same reference numerals, and duplicated description will be omitted. The configuration of the embodiment of FIG. 2 differs from that of the embodiment shown in FIG. 1 in that the active filter 10 includes an adder 100, a high-pass filter 101, an amplifier 102, and a reactor transformer 103.
And the detector 12 includes a high-pass filter 10
1 is output, a signal indicating the on / off state of the amplifier 102, an output current i _A of the amplifier 102, and an output voltage v _A of the amplifier 102 are taken in.

Next, the operation of the embodiment shown in FIG. 2 will be described. Similar to the embodiment of FIG. 1, the thyristor converter 1
The output voltage v _t is input to the active filter 10 after the pulsating component is reduced by the DC filter 2. In the active filter 10, the output voltage v _p of the DC filter 2 and the voltage setting value u are input to the adder 100, and the adder 100 calculates the deviation thereof. An AC component is extracted from the output voltage of the adder 100 by the high-pass filter 101,
This AC component is amplified to a predetermined level by the amplifier 102 and then output to the reactor transformer 103.

The secondary side of the reactor transformer 103 is connected in series with a path having a polarity opposite to that of the primary side, whereby the output voltage of the amplifier 102 is inverted and added to the current i. Therefore, on the secondary side of the reactor transformer 103, an alternating-current component having a phase opposite to the alternating-current component contained in the output voltage v _p of the direct-current filter 2 is induced, and this is the current i. Will be added to.

As a result, the output voltage v _{p of the} DC filter 2
The AC component contained in is canceled and removed by the AC component of the reverse polarity appearing on the secondary side of the reactor transformer 103, and therefore, the electromagnet 3 is supplied with a sufficiently smoothed DC current. Will be supplied.

For this reason, the reactor transformer 103
Is the same as an ordinary transformer, but here, in particular, it is a wideband transformer whose operating frequency ranges from several hertz to several kilohertz, and magnetic saturation does not occur even when a direct current flows through the secondary side. Made in.

In the elementary particle accelerator, the pattern waveform is given as the set value r in a steady operation state such as repetitive operation. At this time, it is desirable to increase the control gain from the viewpoint of high speed control response performance.

Therefore, in this embodiment, the detector 12 detects that the amplifier 102 in the active filter 10 is operating (turned on) when the high speed control response is required. , Next high-pass filter 10
It is detected that the deviation occurring at 1 is within the controllable range of the amplifier 102, and at this time, a signal for selecting the gain increase is provided to the selector 13 so as to increase the gain of the control system. is there.

On the other hand, in the operation command state such as operation start and stop, the active filter 10 is not operated due to the intermittent current as described above. Therefore, the detector 12 detects that the active filter 10 is not operating by utilizing the inactive (off) state of the amplifier 102, and sends a signal for selecting the control gain reduction to the selector 13. It is configured to give.

Therefore, according to this embodiment, in the steady operation state, the gain of the entire control system is sufficiently increased, and as a result, the high speed control response is provided, so that the current control with high accuracy can be surely obtained. At the same time, the overall control gain is reduced at the time of operation commands such as operation start and stop.
It is possible to reliably prevent an unstable operation state.

The detection process by the detector 12 is specifically as follows. That is, first, the on / off state of the amplifier 102 can be easily detected by checking the energized state of the amplifier 102 from the contact signal controlling it.

For detection of excessive output of the active filter 10, the output current i _A of the amplifier 102 and the output voltage v _A are input to the detector 12, and the output current i _A preset by the detector 12 is input. And the output voltage v _A are compared with respective upper limit values, it is possible to detect that each output exceeds the upper limit value, and to provide a signal for selecting the gain reduction to the selector 13.

In this case, as a result, the control gain as a whole is lowered, and the excessive output of the active filter 10 is suppressed. Further, by comparing the output current i _A and the output voltage v _A , the detector 12 can also detect that the excessive output has disappeared. At this time, therefore, by giving a signal for selecting gain increase, the high speed control is performed again. It is possible to return to the operation state having the property.

The detector 12 having such a detection function
Can be easily configured by combining a comparator using an operational amplifier and a reference voltage source. Next, selector 1
As No. 3, it can be easily realized by using a non-inverting operational amplifier and switching a resistor for determining its gain with a switch or the like.

Therefore, according to this embodiment, it is possible to construct a power supply device capable of immediately restarting the operation of the active filter 10 when it returns to its original state, as well as protection of the active filter 10 at the time of excessive output.

Next, as in the above embodiment, when the power supply device according to the present invention is applied to the excitation power supply of the main electromagnet of the elementary particle accelerator, for example, it is input via the adder 9 of FIG. The current setting value (current pattern) r is as shown in FIG. In FIG. 3, the period T _a the incident period for incident particles into the accelerator, T _b is the period of acceleration for accelerating the particles in the accelerator, the period T _c is taken out period of particle, the period T _d Is a reset period for returning the current to the value at the time of incidence.

With respect to such a current set value r, when the period to which the control according to the present invention is applied is divided and shown, the current set value r is set during the period when an operation command such as operation start and stop is issued.
Is a low portion r _t, and a period in which high-speed control is performed by a steady operation command such as repetitive operation is a period in which the current setting value r is a portion r _s . In addition,
Even during a period in which the output of the active filter 10 is excessive due to a sudden change in the power supply voltage or the like, it occurs within the range of this portion r _s .

Next, another embodiment of the present invention will be described. FIG. 4 is also an embodiment of the present invention, in which FIG.
The same elements as those of 1 are denoted by the same reference numerals, and overlapping description will be omitted. This embodiment differs from the embodiment of FIG. 1 in that a detector 1 for detecting the state of the active filter 10 is used.
Only the point to which the detection output of No. 2 is supplied is not the selector 13 but the set value generator 11, and the gain switching signal is supplied from this setting generator 11 to the selector 13.

Therefore, the set value generator 11 in the embodiment of FIG. 4 has a function of inputting a signal from the detector 12 and a function of inputting a signal to the selector 13 in addition to the function of outputting the current set value r. The output function, the function of comparing the input signal from the detector 12 with the current setting value r, and the operation state of the equipment related to this power supply device are taken in and interlocked with them, and as a result, It has a protection interlock function for controlling the signal to be output to the selector 13. The set value generator having such a function can be easily configured by using a computer.

The set value generator 11 inputs the state of the active filter 10 detected by the detector 12,
This signal is compared with the current setting value r, a signal for selecting the optimum gain is generated, and further protection interlock is performed,
A signal for selecting the gain is sent to the selector 13 to determine the gain of the control system.

Therefore, according to this embodiment, by comparing the current set value r with the output of the detector 12, the gain can be set more finely, and at the same time, it can be used with other devices other than the power supply device. Active filter 1 with interlock
It is possible to optimize the output value of 0, and as a result, it is possible to obtain a power supply device having high accuracy and high-speed responsiveness with higher stability.

FIG. 5 shows another embodiment of the present invention.
In the embodiment of FIG. 5, the same elements as those of the embodiment of FIG. 2 are designated by the same reference numerals, and duplicated description will be omitted. The embodiment of FIG. 5 differs from the embodiment shown in FIG. 2 in structure, in that the detection result of the detector 12 for detecting the state of the active filter 10 is directly supplied to the selector 1.
Instead of 3, the set value generator 11 is provided, and the configuration generator 11 supplies a signal to the selector 13.

In the case of the embodiment of FIG. 5, again,
The set value generator 11 has a function of outputting the current set value r, an input function of a detection result from the detector 12, an output function to the selector 13, and a detection result of the input detector 12. It is configured to have a function of comparing the current value i _A with the current setting value r and a protection interlock function. Note that such a function can be easily configured by using a computer as described above.

Therefore, according to this embodiment as well, by comparing the current set value r with the output of the detector 12, the gain can be set more finely, and at the same time, the interface with other devices other than the power supply device can be obtained. The lock allows the output value of the active filter 10 to be optimized, and as a result, a power supply device having high accuracy and high-speed response can be obtained with higher stability.

In the above embodiments, the power supply device according to the present invention is applied to the excitation of the electromagnet of the elementary particle accelerator, but the present invention is applicable to the power storage, superconducting coil, etc. in addition to the elementary particle accelerator. Needless to say, the power supply device can be widely used.

[0054]

According to the present invention, the state of the active filter is detected, and the control gain is always set to the optimum state in accordance with the detected state. It is possible to easily provide a power supply device having sufficiently high accuracy and high-speed controllability at the time of steady operation command such as repeated operation without fear of unstable operation even when the type filter has excessive output. it can.

Further, according to the present invention, the gain selection function for detecting the state of the active filter and always providing the optimum control gain can be controlled externally, so that the comparison with the current command and the protection interlock can be performed. Enabled, start operation,
It is possible to eliminate the factors that make the active filter unstable when an operation command such as stop is issued and when the active filter has an excessive output, and to easily provide a power supply device with high accuracy and high-speed controllability when a steady operation command such as repeated operation is issued. Therefore, the active filter can always be optimally driven.

[Brief description of drawings]

FIG. 1 is a block diagram showing an embodiment of a power supply device according to the present invention.

FIG. 2 is a block diagram showing another embodiment of the power supply device according to the present invention.

FIG. 3 is a waveform diagram showing an example of a current pattern given to a current control system of the power supply device according to the present invention.

FIG. 4 is a block diagram showing another embodiment of the power supply device according to the present invention.

FIG. 5 is a block diagram showing still another embodiment of the power supply device according to the present invention.

[Explanation of symbols]

 1 Thyristor converter 2 DC filter 3 Electromagnet 4 Current detector 5 Constant current control circuit 6 Constant voltage control circuit 7 Automatic pulse phase shifter 8, 9 Adder 10 Active filter 11 Set value generator 12 Detector 13 Selector 100 Adder 101 High-pass filter 102 Amplifier 103 Reactor transformer

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Shoichiro Furuseki 3-1-1, Saiwaicho, Hitachi-shi, Ibaraki Hitachi Ltd. Hitachi factory (72) Inventor Satoshi Hirakawa 3-chome, Saiwaicho, Hitachi, Ibaraki No. 1 within Hitachi Engineering Co., Ltd.

Claims (2)

[Claims] 1. An AC / DC converting means having a switching element for converting AC into DC and outputting the converted DC, current command generating means for generating a current command based on a current pattern flowing through the load, and the current command and the load. A current control means for inputting a deviation from the detected value of the flowing current and generating and outputting an output voltage command of the AC / DC converting means necessary for removing the deviation, and the output voltage command and the AC / DC converting means. A voltage control means for inputting a deviation from the detected output voltage value, generating and outputting a firing phase angle command of the AC / DC converting means necessary for removing the deviation, and the voltage control means based on the firing phase angle command. Control means for controlling the output of the AC / DC converter by controlling the switching element of the AC / DC converter, and pulsating the output voltage of the AC / DC converter by subtracting the output voltage command from the output voltage of the AC / DC converter. And an active type filter for generating a voltage having a phase opposite to that of the pulsating component and superimposing it on the signal on the output side of the AC / DC converting means, and connecting the AC / DC converting means to the load via the active filter. A direct current power supply adapted to supply a current is provided with a detecting means for detecting an operating state of the active filter and a gain selecting means for selecting a gain of a control system by the current controlling means according to a detection result of the detecting means. A power supply device characterized in that the gain of the control system is controlled in accordance with the operating state of the active filter. 2. The invention according to claim 1, wherein the current command generating means compares the current command generated by itself with the detection result of the detecting means, and the comparison result is interlocked with the operating state of the external device. A power supply device having a function of generating a gain control signal, wherein the gain selection means is configured to perform gain selection by the gain control signal.