JP2007157626A - High-frequency control device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a high-frequency control device capable of accurately and stably controlling the phase of a high-frequency voltage without using an analog element such as a phase shifter. <P>SOLUTION: This high-frequency control device comprises: a digital direct synthesizer 1; a sine-wave converter 2 for converting a digital phase signal output from the digital direct synthesizer 1 to a sine-wave amplitude digital signal; a DA converter 3 for converting the sine-wave amplitude digital signal from the sine-wave converter 2 to a high-frequency analog signal; a high-frequency amplifier 4 for amplifying the high-frequency analog signal being the output of the DA converter 3; and a high-frequency acceleration cavity 5 for converting the output from the high-frequency amplifier 4 to a high-frequency voltage to accelerate charged particles. The high-frequency control device is provided, between the output part of the digital direct synthesizer 1 and the sine-wave converter 2, with a digital adder 11 for adding a phase control amount for controlling the phase of the high-frequency voltage generated in the high-frequency acceleration cavity 5 to the digital phase signal output from the digital direct synthesizer 1. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a particle accelerator such as a synchrotron or a linac for accelerating charged particles using a high-frequency voltage, and in particular, a high-frequency that controls the phase of a high-frequency voltage generated in a high-frequency acceleration cavity in order to appropriately accelerate charged particles. The present invention relates to a control device.

  In recent years, in the field of elementary particle physics, engineering application, and medical use, the application field of particle accelerators that accelerate charged particles using a high-frequency voltage such as a synchrotron or a linac is expanding.

  In such a high-frequency particle accelerator, it is necessary to control the phase of the acceleration voltage with high accuracy and high stability in order to accelerate the particles appropriately.

  For this reason, digital direct synthesizers that generate sine waves using digital technology have been applied to high-frequency signal generation sources.

FIG. 9 shows an example of the device configuration of a synchrotron particle accelerator having a high-frequency control device using a conventional digital direct synthesizer. In the figure, a high frequency control device includes a digital direct synthesizer (DDS) 1, a sine wave converter 2 for converting a digital phase signal θ _D output from the digital direct synthesizer 1 into a sinusoidal amplitude digital signal V _RFD, and the sine wave. DA converter 3 for converting the amplitude digital signal into a high-frequency analog signal V _RFA , a phase shifter 21 for controlling the phase of the high-frequency analog signal in accordance with the analog phase control amount θ _A, and a high-frequency power P _in output from the phase shifter 21 And a high frequency acceleration cavity 5 for accelerating charged particles by converting the output P _out of the high frequency amplifier 4 into a high frequency voltage Vc.

Here, the analog phase control amount θ _A of the phase shifter 21 includes the high-frequency voltage Vc generated in the high-frequency acceleration cavity 5 and the current I _B detected by using the CT 6 the current of the charged particles accelerated by the high-frequency voltage Vc. The phase difference between the high-frequency voltage Vc generated in the high-frequency acceleration cavity 5 by the analog controller 22 and the phase difference between the charged particles accelerated by the high-frequency voltage is constant. And

  Next, FIG. 10 shows a method of generating an arbitrary high-frequency signal using the conventional analog adder 42. As an example, a method for obtaining a high-frequency signal in which a frequency twice as high as the basic frequency is superimposed on a high frequency of the basic frequency will be described.

Frequency fc from digital direct synthesizer (DDS1) 1 ₁ In a digital direct synthesizer 1 ₁ for outputting a digital phase signal theta _D1, digital phase signal theta _D1 sine wave transducer 2 ₁ for converting the amplitude digital signal V _RFD1 sine wave, the sine wave amplitude digital signal V _RFD1 DA converter 3 ₁ for converting the signal into a high-frequency analog signal V _RFA1 ,
A digital direct synthesizer (DDS2) 1 ₂ that outputs a digital phase signal θ _D2 at a frequency 2fc that is twice the frequency of the digital direct synthesizer 1 ₁ , and a sine wave converter that converts the digital phase signal θ _D2 into a sinusoidal amplitude digital signal V _RFD2 2 ₂ , a DA converter 3 ₂ that converts the amplitude digital signal V _RFD2 of the sine wave into a high-frequency analog signal V _RFA2 , an analog adder 42 that adds a high-frequency analog signal that is the output of the DA converter, and a high-frequency output from the analog adder high-frequency amplifier 4 for amplifying the power P _in, converts the output P _out of the RF amplifier 4 to a high frequency voltage Vc to accelerate charged particles, it is formed of a high-frequency acceleration cavity 5.

  In order to obtain an arbitrary high-frequency waveform, a digital direct synthesizer, a sine wave converter, and a DA converter are connected in multiple stages, and the frequency of the digital direct synthesizer is increased by 2 to n times to obtain an arbitrary high-frequency waveform. Can do.

  By the way, in the high frequency control apparatus as described above, when controlling the phase of the high frequency signal, the high frequency analog signal converted by the DA converter is controlled using an analog element such as a phase shifter. For this reason, it has been difficult to control with high accuracy and high stability due to temperature characteristics and frequency characteristics of analog elements.

  The present invention has been made in order to solve the above-described problems. For example, the phase can be controlled by adding a phase control amount to a digital phase signal output from a digital direct synthesizer using a digital adder. It is possible to control the phase of a high-frequency signal with high accuracy and high stability without using an analog element such as a detector.

  Further, in the prior art, when generating an arbitrary high-frequency signal, a desired waveform is obtained by adding the high-frequency analog signal converted by the DA converter using an analog adder or the like. However, the above method often has a problem that the desired waveform cannot be obtained unless the frequency of the high-frequency analog signal to be added is increased, and the number of digital direct synthesizers, phase amplitude converters, and DA converters increases. In addition, it is difficult to obtain a desired high-frequency signal with high accuracy and high stability due to the temperature characteristics and frequency characteristics of the analog adder.

  The present invention has been made in order to solve the above-described problems. An arbitrary waveform is applied to a digital phase signal in a phase amplitude converter that converts a digital phase signal output from a digital direct synthesizer into a digital amplitude signal. An object of the present invention is to provide a high-frequency control device that can easily generate an arbitrary waveform by including a phase-amplitude converter that generates the phase-amplitude converter.

  In order to achieve the above object, an invention corresponding to claim 1 includes a digital direct synthesizer, a sine wave converter for converting a digital phase signal output from the digital direct synthesizer into a sinusoidal amplitude digital signal, and A DA converter that converts the sine wave amplitude digital signal converted by the sine wave converter into a high-frequency analog signal, a high-frequency amplifier that amplifies the high-frequency analog signal that is the output of the DA converter, and an output from the high-frequency amplifier is a high-frequency signal A digital phase signal output from the digital direct synthesizer between the output unit of the digital direct synthesizer and the sine wave converter in a high-frequency control device configured by a high-frequency accelerating cavity for converting charged voltage and accelerating charged particles And the high-frequency acceleration cavity It is a high-frequency control apparatus characterized by comprising a digital adder for adding the phase control amount for controlling the phase of the generated high-frequency voltage.

  In order to achieve the above object, an invention corresponding to claim 2 includes a digital direct synthesizer, a sine wave converter for converting a digital phase signal output from the digital direct synthesizer into a sinusoidal amplitude digital signal, and A DA converter that converts the sine wave amplitude digital signal converted by the sine wave converter into a high-frequency analog signal, a high-frequency amplifier that amplifies the high-frequency analog signal that is the output of the DA converter, and an output from the high-frequency amplifier is a high-frequency signal A phase difference detecting a phase difference between a high-frequency voltage generated in the high-frequency acceleration cavity and a charged particle accelerated by the high-frequency voltage in a high-frequency control device composed of a high-frequency acceleration cavity that converts the voltage into a voltage and accelerates the charged particles The detector and the output signal of the phase difference detector are converted to digital signals. An A / D converter that controls the phase difference between a high-frequency voltage generated in the high-frequency acceleration cavity and a charged particle accelerated by the high-frequency acceleration cavity, and the controller The output signal is a phase control amount for controlling the phase of the high-frequency voltage generated in the high-frequency accelerating cavity.

  In order to achieve the above object, an invention corresponding to claim 3 includes a digital direct synthesizer, a sine wave converter for converting a digital phase signal output from the digital direct synthesizer into a sinusoidal amplitude digital signal, and A DA converter that converts the sine wave amplitude digital signal converted by the sine wave converter into a high-frequency analog signal, a high-frequency amplifier that amplifies the high-frequency analog signal that is the output of the DA converter, and an output from the high-frequency amplifier is a high-frequency signal A high-frequency control device configured by a high-frequency accelerating cavity for converting charged voltage and accelerating charged particles, comprising a storage device that stores a pattern signal of a phase difference of charged particles with respect to a high-frequency voltage, and stored in the storage device. A phase difference pattern signal is generated in the high-frequency acceleration cavity. Is a high-frequency acceleration control apparatus characterized by the set to the phase control amount for controlling the phase.

  In order to achieve the above object, an invention corresponding to claim 4 includes a digital direct synthesizer, a sine wave converter for converting a digital phase signal output from the digital direct synthesizer into a sinusoidal amplitude digital signal, and A DA converter that converts the sine wave amplitude digital signal converted by the sine wave converter into a high-frequency analog signal, a high-frequency amplifier that amplifies the high-frequency analog signal that is the output of the DA converter, and an output from the high-frequency amplifier is a high-frequency signal In a high-frequency control device comprising a high-frequency accelerating cavity for converting charged voltage and accelerating charged particles, a power detector for detecting the output power of the high-frequency amplifier, and an AD for converting the detection signal of the power detector into a digital signal Converter and output signal of the AD converter with a high frequency amplifier A power phase converter that converts the phase change amount with respect to the output power, and a value that inverts the output of the power phase from the power phase converter and cancels the phase change amount of the high-frequency voltage generated in the high-frequency acceleration cavity. A high-frequency control device characterized in that a phase control amount for controlling the phase is used.

  In order to achieve the above object, the invention corresponding to claim 5 is a digital direct synthesizer, a phase amplitude converter for converting a digital phase signal output from the digital direct synthesizer into a digital amplitude signal, and the digital amplitude signal. In a high frequency control device comprising: a DA converter that converts an analog high frequency signal; a high frequency amplifier that amplifies a high frequency analog signal that is an output of the DA converter; and an acceleration cavity that converts an output from the high frequency amplifier into a high frequency voltage A high-frequency device for converting a digital phase signal output from the digital direct synthesizer into a digital amplitude signal, comprising a phase amplitude converter for generating an arbitrary waveform with the digital phase signal as an input. Control device

  In order to achieve the above object, an invention corresponding to claim 6 includes a digital direct synthesizer, a phase amplitude converter for converting a digital phase signal output from the digital direct synthesizer into a digital amplitude signal, and a digital amplitude signal. In a high-frequency control device including a DA converter that converts an analog high-frequency signal, a high-frequency amplifier that amplifies a high-frequency analog signal that is an output of the DA converter, and an acceleration cavity that converts an output from the high-frequency amplifier into a high-frequency voltage. A high-frequency device for converting a digital phase signal output from the digital direct synthesizer into a digital amplitude signal, and comprising a storage device for storing the digital amplitude signal corresponding to the digital phase signal on a one-to-one basis. In the control unit That.

  In order to achieve the above object, an invention corresponding to claim 7 includes a digital direct synthesizer, a phase amplitude converter that converts a digital phase signal output from the digital direct synthesizer into a digital amplitude signal, and a digital amplitude signal. In a high-frequency control device comprising a DA converter that converts an analog high-frequency signal, a high-frequency amplifier that amplifies a high-frequency analog signal that is an output of the DA converter, and an acceleration cavity that converts an output from the high-frequency amplifier into a high-frequency voltage. A digital phase signal output from the digital direct synthesizer is converted into a digital amplitude signal, and includes a digital arithmetic unit that receives the digital phase signal and outputs a digital amplitude signal. High frequency A control device.

  According to the first aspect of the present invention, the digital phase signal output from the digital direct synthesizer and the phase control amount for controlling the phase of the high frequency voltage generated in the high frequency acceleration cavity are added using the digital adder. Thus, since the phase of the high frequency voltage can be controlled without using an analog element such as a phase shifter, the phase of the high frequency voltage can be controlled with high accuracy and high stability.

  According to the second aspect of the invention, the phase difference between the high-frequency voltage generated in the high-frequency acceleration cavity and the charged particles accelerated by the high-frequency voltage is detected by the phase difference detector and converted into a digital signal by the AD converter. The digital signal output from the AD converter is input to the controller, and the controller outputs a value that makes the phase difference between the high-frequency voltage generated in the high-frequency acceleration cavity and the charged particles accelerated by the high-frequency acceleration cavity constant. By using a phase control amount that controls the phase of the high-frequency voltage generated in the high-frequency acceleration cavity, it is possible to control the phase difference between the voltage generated in the high-frequency acceleration cavity and the charged particles with high accuracy and high stability. .

  According to a third aspect of the present invention, the apparatus includes a storage device that stores a high-frequency voltage generated in the high-frequency acceleration cavity and a pattern signal of a phase difference of charged particles accelerated by the high-frequency acceleration cavity, and the phase control amount is By using the phase pattern signal, the phase difference between the high-frequency voltage generated in the high-frequency acceleration cavity and the charged particles can be controlled with high accuracy and high stability according to the pattern signal.

  According to the invention described in claim 4, the power detector for detecting the output power of the high frequency amplifier, the AD converter for converting the detection signal of the power detector into a digital signal, and the output signal of the AD converter as an output of the high frequency amplifier A phase / amplitude converter for converting into a phase change amount with respect to power is provided, and a value for inverting the output of the power phase converter and canceling the phase change amount is set as a phase control amount for controlling the phase of the high frequency voltage generated in the high frequency acceleration cavity. This makes it possible to correct the phase change with respect to the output power of the high-frequency amplifier with high accuracy and high stability.

  According to the fifth, sixth, and seventh aspects of the invention, the phase amplitude converter that converts the digital phase signal output from the digital direct synthesizer into a digital amplitude signal generates an arbitrary waveform with respect to the digital phase signal. By adopting a phase / amplitude converter, it is possible not only to obtain an arbitrary waveform without increasing the number of stages of the digital direct synthesizer, the phase / amplitude converter, and the DA converter, but also because no analog adder is used. It is possible to obtain an arbitrary high-frequency waveform with high accuracy and high stability.

  According to the present invention, a phase control amount is added to a digital phase signal output from a digital direct synthesizer using a digital adder, so that the phase of a high-frequency voltage can be adjusted with high accuracy without using an analog element such as a phase shifter. It can be controlled stably.

  Furthermore, according to the present invention, a digital direct synthesizer, a sine wave converter, and a DA converter are provided in multiple stages by using a phase / amplitude converter that outputs an arbitrary waveform with a digital phase signal output from a digital direct synthesizer as an input. Arbitrary high frequency output can be obtained with high accuracy and high stability without connection.

  Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a diagram showing a first embodiment of the present invention. In FIG. 1, the same elements as those in FIG. 9 showing the conventional apparatus are denoted by the same reference numerals, and the description thereof is omitted. The feature of FIG. 1 is that the digital phase signal θ _D output from the digital direct synthesizer 1 and the phase control amount θ _C for controlling the phase of the high-frequency voltage Vc generated in the high-frequency acceleration cavity 5 are added using a digital adder 11. Thus, the phase of the high frequency voltage Vc is controlled.

FIG. 2 is a diagram showing a second embodiment of the present invention, in which a high-frequency voltage Vc generated in the high-frequency acceleration cavity 5 and a current I _B detected by using CT 6 to detect the current of charged particles accelerated by the high-frequency voltage Vc. Is detected using a detector 31, the detected phase difference signal Δφ is converted into a digital signal by an AD converter 32, and θ _C is controlled by a controller 33 so that the phase difference becomes a constant value. Thus, the phase difference between the high-frequency voltage Vc generated in the high-frequency acceleration cavity 5 and the charged particles can be controlled to be constant.

FIG. 3 is a diagram showing a third embodiment of the present invention. A pattern signal of a phase difference between the high-frequency voltage Vc generated in the high-frequency acceleration cavity and the charged particles accelerated by the high-frequency voltage Vc is stored in the storage device 34, and this phase pattern signal is used as the phase control amount θ _C. Thus, it becomes possible to control according to the phase difference pattern between the high-frequency voltage Vc generated in the high-frequency acceleration cavity and the charged particles. FIG. 4 shows a diagram illustrating an example of a phase difference pattern.

FIG. 5 is a diagram showing a fourth embodiment of the present invention. It produces a phase shift with respect to the output power P _out of the RF amplifier, as shown in FIG. To correct this deviation, the output power P _out of the RF amplifier is detected by the power detector 51, and converted into a digital signal using an AD converter 52, the value of the phase shift to the power measured by the power phase converter 53 The phase shift amount with respect to the output power of the high-frequency amplifier can be made zero by setting the phase control amount θ _C to the signal obtained by converting the output signal of the power phase converter 53 by the sign inverter 54. It becomes possible.

FIG. 7 is a diagram for explaining fifth, sixth, and seventh embodiments of the present invention. Fifth Embodiment The phase / amplitude converter 12 receives the digital phase signal θ _D output from the digital direct synthesizer 1 and outputs an arbitrary waveform V _ab .

Sixth Embodiment In a sixth embodiment of the present invention, a storage device is used as the phase / amplitude converter 12. FIG. 8 shows the waveform of the digital amplitude signal V _ab with respect to the inside of the storage device and the digital phase signal. Storage device as shown in figure for the digital phase signal theta _D, stores the digital amplitude signal in a one-to-one, it is possible to output any of the output waveform V _ab.

In the seventh embodiment, a digital arithmetic unit is used as the phase / amplitude converter 12. Digital calculator receives the a digital phase signal theta _D, the output can be output to any output waveform V _ab By providing an arithmetic unit represented by theta _D function f (θ _D).

The block diagram for demonstrating the 1st Embodiment of this invention. The block diagram for demonstrating the 2nd Embodiment of this invention. The block diagram for demonstrating the 3rd Embodiment of this invention. The figure which shows an example of the phase difference pattern of embodiment shown in FIG. The block diagram for demonstrating the 4th Embodiment of this invention. The figure showing the phase change with respect to the high frequency amplifier output electric power of FIG. The block diagram for demonstrating 5th, 6th, 7th embodiment of this invention. The figure which shows the digital amplitude signal with respect to the inside of the memory | storage device of 6th Embodiment of FIG. 7, and a digital phase signal. The block diagram which shows the example of the conventional phase control system. The block diagram for demonstrating the example which produces | generates the conventional arbitrary waveform.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Digital direct synthesizer, 2 ... Sine wave converter, 3 ... DA converter, 4 ... High frequency amplifier, 5 ... High frequency acceleration cavity, 6 ... CT, 11 ... Digital adder, 12 ... Phase amplitude converter, 21 ... Phase shift 22 ... Analog controller 31 ... Phase difference detector 32 ... AD converter 33 ... Controller 34 ... Storage device 51 ... Power detector 52 ... AD converter 53 ... Power phase converter 54 ... Sign inversion vessel.

Claims (7)

A digital direct synthesizer, a sine wave converter that converts a digital phase signal output from the digital direct synthesizer into a sine wave amplitude digital signal, and a sine wave amplitude digital signal converted by the sine wave converter A DA converter that converts the signal into a signal, a high-frequency amplifier that amplifies the high-frequency analog signal that is the output of the DA converter, and a high-frequency acceleration cavity that converts the output from the high-frequency amplifier into a high-frequency voltage and accelerates charged particles. In the high frequency control device,
A phase control amount for controlling the phase of the high-frequency voltage generated in the high-frequency acceleration cavity and the digital phase signal output from the digital direct synthesizer between the output unit of the digital direct synthesizer and the sine wave converter A high frequency control device comprising a digital adder for adding. A digital direct synthesizer, a sine wave converter that converts a digital phase signal output from the digital direct synthesizer into a sine wave amplitude digital signal, and a sine wave amplitude digital signal converted by the sine wave converter A DA converter that converts the signal into a signal, a high-frequency amplifier that amplifies the high-frequency analog signal that is the output of the DA converter, and a high-frequency acceleration cavity that converts the output from the high-frequency amplifier into a high-frequency voltage and accelerates charged particles. In the high frequency control device,
A phase difference detector that detects a phase difference between a high-frequency voltage generated in the high-frequency acceleration cavity and charged particles accelerated by the high-frequency voltage; an AD converter that converts an output signal of the phase difference detector into a digital signal; A controller that controls the output signal of the AD converter to a value that makes the phase difference between the high-frequency voltage generated in the high-frequency acceleration cavity and the charged particles accelerated by the high-frequency acceleration cavity constant, and the output signal from the controller A high frequency control apparatus characterized in that a phase control amount for controlling a phase of a high frequency voltage generated in the high frequency acceleration cavity is used. A digital direct synthesizer, a sine wave converter that converts a digital phase signal output from the digital direct synthesizer into a sine wave amplitude digital signal, and a sine wave amplitude digital signal converted by the sine wave converter A DA converter that converts the signal into a signal, a high-frequency amplifier that amplifies the high-frequency analog signal that is the output of the DA converter, and a high-frequency acceleration cavity that converts the output from the high-frequency amplifier into a high-frequency voltage and accelerates charged particles. In the high frequency control device,
A storage device storing a pattern signal of a phase difference of charged particles with respect to a high-frequency voltage, and controlling the phase of the high-frequency voltage generated in the high-frequency accelerating cavity using the phase difference pattern signal stored in the storage device A high-frequency acceleration control device characterized by a phase control amount. A digital direct synthesizer, a sine wave converter that converts a digital phase signal output from the digital direct synthesizer into a sine wave amplitude digital signal, and a sine wave amplitude digital signal converted by the sine wave converter A DA converter that converts the signal into a signal, a high-frequency amplifier that amplifies the high-frequency analog signal that is the output of the DA converter, and a high-frequency acceleration cavity that converts the output from the high-frequency amplifier into a high-frequency voltage and accelerates charged particles. In the high frequency control device,
A power detector that detects output power of the high-frequency amplifier, an AD converter that converts a detection signal of the power detector into a digital signal, and an output signal of the AD converter that converts a phase change amount with respect to output power of the high-frequency amplifier A phase control amount for controlling the phase of the high-frequency voltage generated in the high-frequency accelerating cavity with a value that reverses the amount of phase change by inverting the output of the power phase from the power phase converter. A high frequency control device characterized by that. A digital direct synthesizer, a phase / amplitude converter that converts a digital phase signal output from the digital direct synthesizer into a digital amplitude signal, a DA converter that converts the digital amplitude signal into an analog high-frequency signal, and an output of the DA converter In a high-frequency control device configured by a high-frequency amplifier that amplifies a high-frequency analog signal and an acceleration cavity that converts an output from the high-frequency amplifier into a high-frequency voltage,
A high frequency control comprising a phase amplitude converter for converting a digital phase signal output from the digital direct synthesizer into a digital amplitude signal and generating an arbitrary waveform with the digital phase signal as an input. apparatus. A digital direct synthesizer, a phase / amplitude converter that converts a digital phase signal output from the digital direct synthesizer into a digital amplitude signal, a DA converter that converts a digital amplitude signal into an analog high-frequency signal, and an output of the DA converter In a high-frequency control device composed of a high-frequency amplifier that amplifies a high-frequency analog signal and an acceleration cavity that converts the output from the high-frequency amplifier into a high-frequency voltage,
A high-frequency device for converting a digital phase signal output from the digital direct synthesizer into a digital amplitude signal, and comprising a storage device for storing the digital amplitude signal corresponding to the digital phase signal on a one-to-one basis. Control device. A digital direct synthesizer, a phase / amplitude converter that converts a digital phase signal output from the digital direct synthesizer into a digital amplitude signal, a DA converter that converts a digital amplitude signal into an analog high-frequency signal, and an output of the DA converter In a high-frequency control device composed of a high-frequency amplifier that amplifies a high-frequency analog signal and an acceleration cavity that converts the output from the high-frequency amplifier into a high-frequency voltage,
A digital phase signal output from the digital direct synthesizer is converted into a digital amplitude signal, and includes a digital arithmetic unit that receives the digital phase signal and outputs a digital amplitude signal. High-frequency control device.

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