JP2817760B2 - Synchrotron power supply - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a synchrotron power supply for accelerating or accelerating an electron beam or the like at a high speed.

[0002]

2. Description of the Related Art FIG. 5 shows a configuration of a conventional synchrotron power supply device using a series transistor. In the figure, 1 is a power transformer, 2 is a thyristor converter, 3 is a ripple elimination filter, 4 is a series transistor, 5 is a load, 6 is a current reference signal generation circuit that generates a pattern current reference signal _Iref , and 7 is a current sensor. , 8 is a current controller (CC), 9 is a base drive circuit of the series transistor 4, 10 is a voltage reference signal generation circuit for generating a pattern voltage reference signal _Vref , 11 is a voltage sensor, 12 is a voltage controller (VC), 13 Is the thyristor converter 2
Is a phase control circuit (PHC) for controlling the energization of.

Next, the operation of the conventional example will be described. The pattern current reference signal _Iref output from the current reference signal generation circuit 6 is compared with the actual output current flowing through the load 5 detected by the current sensor 7, and the current controller 8 is controlled so that these deviations are minimized. Operates to control the base current of the series transistor 4 through the base drive circuit 9. As a result, the absorption voltage V _CE between the collector and the emitter of the series transistor 4 changes,
The output current flowing through the load 5 is equal to the pattern current reference signal I.
It changes following _ref .

On the other hand, the absorption voltage V _CE between the collector and the emitter of the series transistor 4 is detected by a voltage sensor 11 and applied to a pattern voltage reference signal V _ref (normally a fixed value) output from a voltage reference signal generation circuit 10. The thyristor converter 2 is driven through the voltage controller 12 and the phase control circuit 13 so as to match, and the output voltage is controlled.

As a result of the above-described operation, a high-precision current pattern tracking control utilizing the excellent current control characteristics of the series transistor 4 is performed without applying an excessive voltage to the series transistor 4.

[0006]

The conventional synchrotron power supply device using the series transistor has a problem that the response speed of the voltage control is slow because of the configuration described above. To increase the response speed of the voltage control, a sharp rise of the output current is required. However, since the load of the synchrotron power supply is a reactive load, it is difficult to increase the speed.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problem, and applies a series transistor to a synchrotron power supply device to enable high-precision current control, and to provide high-precision current control even in an acceleration-accumulation mode. An object is to provide a power supply device that can ensure control.

[0008]

SUMMARY OF THE INVENTION The present invention provides a thyristor converter.
Heat exchanger, ripple rejection filter, series transistor
The main circuit is composed of
In a synchrotron power supply that energizes repeatedly,
Provided on the input side of the series transistor,
A voltage detector that detects the output voltage of the iristor converter (voltage
Sensor) and bias the series transistor
Base drive circuit for the thyristor converter
First reference signal generating means for providing a pattern voltage reference signal
(Voltage reference signal generation circuit) and the base drive circuit
Supply the pattern current reference signal to the
Second reference signal generating means for driving the transistor (current reference signal
Generating circuit), an output current flowing through the load coil,
To reduce the current deviation from the pattern current reference signal
The pattern output from the first reference signal generating means.
A self-learning device for sequentially correcting the ground voltage reference signal;
If the current deviation is large by the self-learning device,
When the series transistor is brought into a fully conducting state;
The output of the voltage detector and the first reference signal generating means.
Driving the thyristor converter with force and
If the current deviation is small, the
Driving the series transistor
The output of the voltage detector and the first reference signal generating means.
The thyristor converter by applying a predetermined bias voltage to the force
Switching means for controlling the
It is a crotron power supply device, by the self-learning device,
The pattern voltage reference so that the current deviation is small.
The signal is sequentially corrected, and the current deviation converges within a predetermined range.
After that, the series transistor is connected to the pattern current base.
It is controlled by a quasi-signal.

[0009]

In the synchrotron power supply according to the present invention, the pattern voltage reference signal to the thyristor converter that performs feedforward control is sequentially corrected by self-learning control, and the current deviation between the output current flowing through the load and the pattern current reference signal is reduced. It is reduced sequentially. As a result, even if the control state is switched to the control state based on the pattern current reference signal, high-speed and accurate adjustment can be performed to a state where an excessive voltage is not applied to the series transistor.

[0010]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 shows a first embodiment of a synchrotron power supply according to the present invention. In the figure, the same parts as those of the conventional synchrotron power supply device (FIG. 5) are denoted by the same reference numerals, and description thereof will be omitted.

In FIG. 1, reference numeral 20 denotes a voltage sensor; 21, a self-learning device for detecting a current deviation in one cycle of energization and correcting the pattern voltage reference signal _Vref based on the current deviation; A voltage reference signal generating circuit for generating a pattern voltage reference signal _Vref sequentially corrected by
Reference numerals a and 25b denote control switches for the series transistor 4.

Next, the operation of the first embodiment will be described.
At the beginning of operation, the switches 25a and 25b are turned off.
F, and each contact is set in the state shown in the figure.
Therefore, in this state, a forward bias current sufficient to maintain the series transistor 4 in the saturation region is supplied from the bias power supply 24 through the base drive circuit 9, and the series transistor 4 is in a completely conductive state.

In the above state, the thyristor converter 2 operates according to the pattern voltage reference signal _Vref supplied from the voltage reference signal generator 22. At this time, the output current flowing to the load 5 is detected by the current sensor 7. Then, a current deviation between the detected output current and a target pattern current reference signal _Iref provided from the current reference signal generator 6 is obtained, and the deviation value is sent to the self-learning device 21.

The self-learning device 21 calculates a correction value for making the current deviation value zero according to a preset program, and uses the correction value to calculate a pattern voltage reference output from the voltage reference signal generation circuit 22. Modify the signal _Vref . By repeating such a process of correcting the pattern voltage reference signal _Vref by self-learning for each energization cycle, the current deviation is gradually reduced. When the self-learning device 22 confirms that the current deviation has converged within a predetermined range, the self-learning device 22 executes the switch 2 from the next energizing cycle.
The switches 5a and 25b are turned on, and the switch 25a is connected to the bias power supply 23 side, and the switch 25b is connected to the current controller 8 side.

Thus, the current controller 8 and the base drive circuit 9 are provided at the base of the series transistor 4.
The pattern current reference signal I _ref is supplied from the current reference signal generating circuit 6 through the thyristor converter 2, and a voltage corresponding to the target absorption voltage V _CE of the series transistor 4 is added to the thyristor converter 2 from the bias power supply 23. A pattern voltage reference signal is provided. As a result, current control can be accurately performed without causing disturbance in the control system.

FIG. 2 shows a second embodiment of the present invention. In the figure, 101 and 102 are power transformers, 121 and 12
2 is a voltage controller, 201 and 203 are voltage sensors,
211 is a self-learning device, 221 and 222 are reference voltage signal generation circuits, 261 is a forcing thyristor, and 262 is a regulator thyristor.

In the second embodiment, the thyristor converter 2 in the first embodiment is equivalent to a forcing thyristor 261 for generating a voltage corresponding to a reactance drop of the load 5 and a resistance drop of the load 5. A voltage thyristor 262 for generating a voltage is divided into two parts, and a pattern voltage reference signal applied to each is corrected based on a gradient of a current deviation and an instantaneous value of the current deviation at a certain time interval. is there.

With this configuration, the accuracy and efficiency of self-learning can be increased, and the current control at the time of transition to the accumulation mode in the acceleration-accumulation mode operation can be maintained with high accuracy. FIG. 6 shows an output waveform example of each unit.

FIG. 3 shows a third embodiment of the present invention. This third embodiment has the same configuration as the second embodiment,
A bypass switch 26 is provided in parallel with the forcing thyristor 261, and when the storage mode is reached, the bypass switch 26 is turned on.
1 is configured to bypass. With this configuration, the reactive power can be reduced, and the power factor can be improved.

FIG. 4 shows a fourth embodiment of the present invention. This fourth embodiment has the same configuration as the second embodiment,
Between the collector and the emitter of the series transistor 4, a voltage reference signal generating circuit 10 for controlling the absorption voltage V _CE of the series transistor 4 to be constant and a voltage sensor 11 _, similar to the conventional synchrotron power supply device (FIG. 5). It is provided with a voltage controller 12. If the switch 27 is turned on after shifting to the accumulation mode, the load on the series transistor 4 can be reduced, and the device can be economically constructed without impairing the control performance.

[0021]

As is apparent from the above description,
According to the present invention, voltage control of the thyristor converter is performed using self-learning control, and the current deviation is made to converge within a predetermined range in advance, so that the present invention can be applied to a circuit that operates the series transistor at high speed, In the continuous acceleration mode and the acceleration-accumulation mode, a highly accurate synchrotron power supply utilizing the excellent current control characteristics of the transistor can be obtained.

[Brief description of the drawings]

FIG. 1 is a circuit diagram showing a first embodiment of the present invention.

FIG. 2 is a circuit diagram showing a second embodiment of the present invention.

FIG. 3 is a circuit diagram showing a third embodiment of the present invention.

FIG. 4 is a circuit diagram showing a fourth embodiment of the present invention.

FIG. 5 is a circuit diagram showing a conventional example.

FIG. 6 is a diagram illustrating an example of an output waveform of a synchrotron power supply device.

[Explanation of symbols]

 2 Thyristor converter 3 Ripple elimination filter 4 Series transistor 5 Load 6 Current reference signal generation circuit 21 Self-learning device 22 Voltage reference signal generation circuit 25a, 25b Control switch

Claims (1)

(57) [Claims] A thyristor converter and a ripple rejection filter.
The main circuit is composed of a filter and a series transistor
The pattern current to the load coil repeatedly.
In the cyclotron power supply device, the power supply is provided on the input side of the series transistor,
A voltage detector for detecting an output voltage of the iristor converter, and a base for biasing the series transistor
A drive circuit and a pattern voltage reference signal to the thyristor converter
A first reference signal generating means for supplying a pattern current reference signal to the base drive circuit;
A second reference signal for driving the series transistor
Generating means, an output current flowing through the load coil, and the pattern current base.
In order to reduce the current deviation from the reference signal, the first reference
The pattern voltage reference signal output from the signal generating means;
Self-learning device that sequentially corrects, and the current deviation is large by the self-learning device.
When the series transistor is brought into a fully conducting state,
Both, the voltage detector and the first reference signal generating means
Drives the thyristor converter with the output of
If the current deviation is small, the pattern current reference signal
Driving the series transistor based on
In addition, the voltage detector and the first reference signal generating means
The thyristor conversion is performed by applying a predetermined bias voltage to the output.
Switching means for controlling the heater.
Synchrotron power supply.