Current charge converter and accelerator beam diagnosis system

Abstract

The invention provides a current charge converter and an accelerator beam diagnosis system, and relates to the technical field of beam diagnosis, the converter comprises a conversion circuit and a self-checking logic module, the conversion circuit comprises a signal conversion circuit and an analog bandwidth selection circuit, the signal conversion circuit is used for receiving a current charge signal and a target gain gear signal, and the analog bandwidth selection circuit is used for selecting the current charge signal and the target gain gear signal; converting the current charge signal into a target voltage signal under the corresponding gain based on the target gain gear signal; the target gain gear signal is determined from a preset gain range corresponding to the signal conversion circuit, and the preset gain range is 103-1010; the analog bandwidth selection circuit is used for performing noise control on the target voltage signal based on the analog bandwidth selection signal to obtain a filtering signal; the output end of the self-checking logic module is connected with the input end of the conversion circuit, and the self-checking logic module is used for generating a self-checking current signal with a fixed frequency in a self-checking mode. The dynamic range is ultra-wide, and real-time self-checking and self-testing can be achieved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of beam diagnosis, in particular to a current-charge converter and an accelerator beam diagnosis system. BACKGROUND

[0002] With the progress of accelerator technology, especially the development of high-energy accelerators, higher requirements are put forward for the accuracy and real-time performance of beam diagnosis. With the further enhancement of beam power and the development of terminal experimental physics, the requirements for beam quality are also becoming higher and higher. Beam diagnosis systems are also developing towards high precision and multi-function, and new beam measurements require accurate measurement of weak signals in the order of pA and pC to meet the increasingly high measurement requirements for beam quality. At the same time, the development of real-time two-dimensional measurement of beam requires increasing channel and position accuracy. The acquisition of current or charge signals is a very important link in the accelerator beam diagnosis system. Through the current or charge signals and various types of front-end probes, the beam intensity, beam loss, beam position and other information of the accelerator can be accurately obtained. Taking a single wire as an example, in the process of measuring the beam profile and emittance, the beam signal will directly hit the gold-coated tungsten wire or carbon wire with a diameter of tens to hundreds of microns. The charge of the charged particles in the beam will accumulate on the wire. By measuring the size of the charge signal accumulated on the wire at different positions and the real-time wire position, the beam profile or emittance and other beam information can be obtained. As a very important link in the entire system, the performance of the charge signal acquisition and converter directly affects the function and accuracy of the entire beam measurement system.

[0003] Limited to the actual needs of accelerators, especially heavy ion accelerators, the accelerator field requires the measurement of charge and current to cover primary particle beams and secondary particle beams, with a large dynamic range. In addition, considering the influence of radiation dose, it is also required to be self-checking and self-testing, and to monitor the working state of the system in real time. At present, the development of such converters in the field of accelerators is relatively lagging behind, and they cannot meet the requirements of the accelerator field for beam measurement systems. SUMMARY

[0004] The present application provides a current-charge converter and an accelerator beam diagnosis system to solve the defects that the beam measurement system in the prior art has a small dynamic range and cannot be self-checking and self-testing when measuring charge and current.

[0005] The present application provides a current-charge converter, comprising a conversion circuit and a self-checking logic module, wherein: The conversion circuit comprises a signal conversion circuit and an analog bandwidth selection circuit, the signal conversion circuit is used for receiving a current charge signal and a target gain position signal, and converting the current charge signal into a target voltage signal under a corresponding gain based on the target gain position signal; the target gain position signal is determined from a preset gain range corresponding to the signal conversion circuit, and the preset gain range is 10 3 to 10 10 ; the analog bandwidth selection circuit is used for performing noise control on the target voltage signal based on an analog bandwidth selection signal to obtain a filtered signal; An output end of the self-checking logic module is connected to an input end of the conversion circuit, and the self-checking logic module is used for generating a self-checking current signal with a fixed frequency in a self-checking mode and outputting the self-checking current signal to the conversion circuit for self-checking.

[0006] According to the current charge converter provided in the application, the signal conversion circuit comprises a plurality of gain position circuits connected in parallel and a feedback amplifier; The plurality of gain position circuits connected in parallel are connected in parallel between the inverting input end and the output end of the feedback amplifier; In a case where a target gain position signal is received at a control end of a target gain position circuit, the feedback amplifier is used for converting a received current charge signal into a target voltage signal under a gain corresponding to the target gain position circuit; and the target gain position circuit is any one of the plurality of gain position circuits.

[0007] According to the current charge converter provided in the application, the analog bandwidth selection signal comprises a bandwidth selection sub-signal and an output control sub-signal; The analog bandwidth selection circuit comprises a first relay, a second relay, a first bandwidth branch and a second bandwidth branch, wherein: The first bandwidth branch and the second bandwidth branch are connected in parallel, and the first relay and the second relay are respectively arranged at two ends of a parallel circuit corresponding to the first bandwidth branch and the second bandwidth branch; The bandwidth selection sub-signal is used for switching a conduction path of the first relay to determine a target bandwidth branch from the first bandwidth branch and the second bandwidth branch; the target bandwidth branch is used for filtering a target voltage signal received by the first relay to obtain a filtered signal; and the output control sub-signal is used for switching an output path of the filtered signal, and the conduction paths of the first relay and the second relay are the same.

[0008] According to the current charge converter provided in the application, the conversion circuit further comprises a coupling selection circuit, the coupling selection circuit comprises a third relay, an amplification circuit and an integration circuit, wherein: The amplification circuit is configured to amplify the received target voltage signal to obtain a voltage amplified signal. The integration circuit is configured to integrate the voltage amplified signal to obtain a direct current signal. The control end of the third relay is configured to receive a coupling selection signal, and a level state of the coupling selection signal is configured to control a conduction path of the third relay to control whether the direct current signal is fed back to an input end of the amplification circuit to obtain an amplified target voltage signal and send the amplified target voltage signal to an input end of the analog bandwidth selection circuit.

[0009] According to the current charge converter provided by the application, the output driving circuit is connected to the output end of the analog bandwidth selection circuit, and the output end of the output driving circuit is connected to a collection device.

[0010] According to the current charge converter provided by the application, the self-checking logic module comprises a self-excited oscillator, a voltage-current conversion unit and an output interface, wherein: The self-excited oscillator is configured to generate a self-checking pulse signal with a fixed frequency in a self-checking mode. The voltage-current conversion unit is configured to convert the self-checking pulse signal into a self-checking current signal. The output interface is configured to send the self-checking current signal to the input end of the signal conversion circuit.

[0011] According to the current charge converter provided by the application, the control logic module comprises a local control unit, a remote control unit and a multiplexer, wherein: The local control unit or the remote control unit is configured to determine a target relay operation signal in response to user operation, and the target relay operation signal comprises a target gain gear signal, an analog bandwidth selection signal or a coupling selection signal. The multiplexer is configured to send the target relay operation signal to a corresponding target relay based on a signal source of the target relay operation signal to drive the target relay to act.

[0012] According to the current charge converter provided by the application, the protection logic module comprises a signal coupling unit, an absolute value calculation unit and a threshold comparison unit, wherein: The signal coupling unit is configured to receive the amplified target voltage signal output by the coupling selection circuit. The absolute value calculation unit is configured to flip the negative signal in the amplified target voltage signal to obtain a flipped voltage signal. The threshold comparison unit is configured to compare the flipped voltage signal with a voltage threshold to obtain a voltage comparison result.

[0013] The current charge converter further comprises a power supply module configured to supply power to devices in the current charge converter.

[0014] The application further provides an accelerator beam diagnosis system comprising an acquisition device and the current charge converter according to any one of the above. The output end of the current charge converter is connected to the input end of the acquisition device, and the current charge converter is configured to send a target output signal to the acquisition device for visualization.

[0015] The current charge converter and the accelerator beam diagnosis system provided by the application can convert a current charge signal into a target voltage signal under a corresponding gain through a signal conversion circuit in a conversion circuit according to a received target gain position signal, and can control noise of the target voltage signal through an analog bandwidth selection circuit according to a received analog bandwidth selection signal to obtain a filtered signal. Meanwhile, the self-checking logic module can also generate a fixed-frequency self-checking current signal in a self-checking mode and output the self-checking current signal to the input end of the signal conversion circuit for self-checking. In the application, the current charge signal has a preset gain range of 10 3 to 10 10 pA, the dynamic range is wide, and the signal conversion of the current charge signal of 10 mA to 10 pA can be realized. The noise of the converted target voltage signal is controlled through the analog bandwidth selection circuit, the filtered signal has a wide analog bandwidth and a low noise level, and the distortion-free conversion of the signal is ensured. In addition, the working state of the entire converter can be detected in real time through the self-checking of the self-checking logic module. BRIEF DESCRIPTION OF DRAWINGS

[0016] In order to more clearly illustrate the technical solutions in the application or the prior art, the following will briefly introduce the drawings needed to be used in the embodiments or the prior art description. Obviously, the drawings in the following description are some embodiments of the application, and other drawings can also be obtained by those skilled in the art without any creative effort.

[0017] Figure 1 is a structural schematic diagram of the current charge converter provided by the embodiments of the application.

[0018] Figure 2 is a structural schematic diagram of the signal conversion circuit provided by the embodiments of the application.

[0019] Figure 3 is a structural schematic diagram of a coupling selection circuit provided by an embodiment of the present application.

[0020] Figure 4 is a structural schematic diagram of an analog bandwidth selection circuit provided by an embodiment of the present application.

[0021] Figure 5 is a structural schematic diagram of an output driving circuit provided by an embodiment of the present application.

[0022] Figure 6 is a structural schematic diagram of a self-checking logic module provided by an embodiment of the present application.

[0023] Figure 7 is a structural schematic diagram of a control logic module provided by an embodiment of the present application.

[0024] Figure 8 is a structural schematic diagram of a protection logic module provided by an embodiment of the present application.

[0025] Figure 9 is a structural schematic diagram of a power supply module provided by an embodiment of the present application.

[0026] Figure 10 is a test result schematic diagram of electronic dynamic range and linearity error provided by an embodiment of the present application.

[0027] Figure 11 is a test result schematic diagram of bandwidth test provided by an embodiment of the present application.

[0028] Reference signs: 100: conversion circuit; 110: signal conversion circuit; 111: gain step circuit; 112: feedback amplifier; 113: gas discharge tube; 120: coupling selection circuit; 121: third relay; 122: amplification circuit; 123: integration circuit; 130: analog bandwidth selection circuit; 131: first relay; 132: second relay; 133: first bandwidth branch; 134: second bandwidth branch; 140: output driving circuit; 200: self-checking logic module; 210: self-excited oscillator; 220: voltage-current conversion unit; 230: output interface; 300: control logic module; 310: local control unit; 320: remote control unit; 330: multiplexer; 400: protection logic module; 410: signal coupling unit; 420: absolute value calculation unit; 430: threshold comparison unit; 500: power supply module; 510: analog power conversion unit; 520: digital power conversion unit. DETAILED DESCRIPTION

[0029] In order to make the objects, technical solutions and advantages of the present application clearer, the technical solutions in the present application will be clearly and completely described below with reference to the drawings in the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative work fall within the protection scope of the present application.

[0030] In order to solve the problems of small dynamic range and inability to self-test in the charge and current measurement of the beam measurement system in the prior art, the embodiment of the present application provides a current-charge converter, Figure 1 which is a structural schematic diagram of the current-charge converter provided by the embodiment of the present application, as shown in the figure, Figure 1 the current-charge converter comprises a conversion circuit 100 and a self-test logic module 200.

[0031] The conversion circuit 100 comprises a signal conversion circuit 110 and an analog bandwidth selection circuit 130. The signal conversion circuit 110 is used to receive a current signal and a target gain position signal, and convert the current signal into a target voltage signal under a corresponding gain based on the target gain position signal. The target gain position signal is determined from a preset gain range corresponding to the signal conversion circuit 110, and the preset gain range is 10 3 to 10 10 ; and the analog bandwidth selection circuit 130 is used to perform noise control on the target voltage signal based on an analog bandwidth selection signal to obtain a filtered signal.

[0032] Specifically, in the conversion circuit 100, the input end of the signal conversion circuit 110 is connected to a detector. After detecting a current signal, the detector can send the current signal to the input end of the signal conversion circuit 110. A feedback-type resistance network is arranged in the signal conversion circuit 110. The feedback-type resistance network can receive a target gain position signal determined in response to user operation. Different gain positions correspond to different target gain position signals, and the target gain position signal can control the on-off state of the corresponding relay switch in the feedback-type resistance network to obtain the corresponding gain. Then, the input current signal can be amplified by the feedback-type resistance network by a corresponding gain multiple, and then converted into a target voltage signal.

[0033] It should be noted that, due to the adoption of the feedback-type conversion in the current-charge converter, the input impedance of the current-charge converter is 0Ω, and the equivalent output voltage of the detector is 0V. The feedback-type resistance network effectively reduces the influence of the source impedance. In actual accelerator applications, the detection efficiency of the detector with low insulation resistance can be well guaranteed.

[0034] It should be noted that the impedance of the current charge converter is characterized as the voltage gain of the feedback resistance network or the conversion coefficient of the current charge converter. In order to meet the requirement of a large dynamic range of the beam measurement system in the field of accelerators, a plurality of gain positions, such as 10 3 , 10 5 , 10 7 , 10 9 , and 10 10 , are arranged in the feedback resistance network in the embodiment of the present application, so as to ensure that the preset gain range of the signal conversion circuit 110 is 10 3 to 10 10 . The feedback resistance network can amplify the collected current signal by different gain multiples, has a super-wide dynamic range, and can meet the signal collection and conversion of extremely weak current signals in the range of 10 mA to 10 pA.

[0035] Since the total noise level of white noise follows the principle of bandwidth integration, after obtaining the target voltage signal, the analog bandwidth of the target voltage signal is controlled through the analog bandwidth selection circuit 130, so as to control the noise level of the current charge converter, ensure the distortionless conversion of the signal, and further ensure the accuracy of subsequent beam diagnosis.

[0036] In addition, the output end of the self-checking logic module 200 is connected to the input end of the conversion circuit 100, and the self-checking logic module 200 is used to generate a self-checking current signal of a fixed frequency in a self-checking mode, and output the self-checking current signal to the conversion circuit 100 for self-checking.

[0037] Specifically, in order to monitor the running state of the current charge converter in real time and ensure the reliability of signal conversion, the self-checking logic module 200 is further arranged in the embodiment of the present application, which can trigger the self-checking logic module 200 to enter the self-checking mode at a regular time or an irregular time, so as to generate a self-checking current signal of a fixed frequency, and output the self-checking current signal to the input end of the conversion circuit 100, i.e., the input end of the signal conversion circuit 110, for signal conversion, so as to perform self-checking on the current charge converter.

[0038] Further, Figure 2 is a structural schematic diagram of the signal conversion circuit provided by the embodiment of the present application, as shown in Figure 2 , the signal conversion circuit 110 includes a plurality of gain position circuits 111 connected in parallel and a feedback amplifier 112.

[0039] The plurality of gain position circuits 111 connected in parallel are connected in parallel between the inverting input end and the output end of the feedback amplifier 112.

[0040] In the case that the target gain position circuit receives the target gain position signal at the control end, the feedback amplifier 112 is configured to convert the received current signal into a target voltage signal under the gain corresponding to the target gain position circuit; and the target gain position circuit is any one of the plurality of gain position circuits 111.

[0041] Specifically, in the signal conversion circuit 110, the plurality of gain position circuits 111 and the feedback amplifier 112 connected in parallel constitute a feedback resistance network, each gain position circuit 111 includes a conversion resistance and corresponds to a gain position. For example, the gain position corresponding to the gain position circuit 111 with a conversion resistance of 100Ω is 10 3 ; the gain position corresponding to the gain position circuit 111 with a conversion resistance of 10KΩ is 10 5 ; the gain position corresponding to the gain position circuit 111 with a conversion resistance of 1MΩ is 10 7 ; the gain position corresponding to the gain position circuit 111 with a conversion resistance of 100MΩ is 10 9 ; and the gain position corresponding to the gain position circuit 111 with a conversion resistance of 1GΩ is 10 10 . The output voltage range of each gain position circuit 111 is 1V to 10mV. In addition, each gain position circuit 111 further includes two relays, and the switching of the gain position is realized by controlling the two relays. The two relays in each gain position circuit 111 are in an open state by default. If it is necessary to switch to the gain position corresponding to the gain position circuit 111, the two relays in the target gain position circuit can be controlled to switch from the open state to the closed state by the target gain position signal, and then during the signal conversion of the current signal, the target gain position circuit can amplify the current signal by a target gain multiple, and the feedback amplifier 112 can convert the amplified current signal into a target voltage signal and transmit the target voltage signal to the coupling selection circuit 120 of the next stage.

[0042] Optionally, the relays in each gain position circuit 111 can be monostable relays, and the contact resistance of the monostable relays is less than 100mΩ, which can be basically ignored.

[0043] Optionally, in order to further improve the measurement accuracy, the feedback amplifier 112 can be a Jfet type high input impedance low noise wideband amplifier AD637, the input bias current of the feedback amplifier 112 is less than 5pA, and the input current noise is less than 1.6fA√Hz, and a gain bandwidth product (GBW) greater than 11MHz can be required to ensure the bandwidth of the system.

[0044] In addition, a capacitor is arranged in each gain stage circuit 111, which is connected in parallel to the two ends of the conversion resistor, adds a pole in the whole signal chain diagram, and further ensures the stability of the current charge converter.

[0045] In addition, the input end of the signal conversion circuit 110 is further connected with a gas discharge tube 113, which is used to protect the subsequent circuit when a large charge impact exists.

[0046] Further, Figure 3 is a structural schematic diagram of the coupling selection circuit provided by the embodiment of the present application, as Figure 3 As shown in the figure, the conversion circuit 100 further comprises a coupling selection circuit 120, the coupling selection circuit 120 comprises a third relay 121, an amplification circuit 122 and an integration circuit 123, wherein: The amplification circuit 122 is used to amplify the received target voltage signal to obtain a voltage amplified signal; The integration circuit 123 is used to integrate the voltage amplified signal to obtain a direct current signal; The control end of the third relay 121 is used to receive a coupling selection signal, the level state of the coupling selection signal is used to control the conduction path of the third relay 121, so as to control whether the direct current signal is fed back to the input end of the amplification circuit 122 to obtain an amplified target voltage signal, and the amplified target voltage signal is sent to the input end of the analog bandwidth selection circuit 130.

[0047] Specifically, in the coupling selection circuit 120, the first end of the amplification circuit 122 is used to receive a target voltage signal, the second end of the amplification circuit 122 is connected with the third end of the third relay 121, the output end of the amplification circuit 122 is connected with the second end of the integration circuit 123, the third end of the integration circuit 123 is grounded, the first end of the integration circuit 123 is connected with the first end of the third relay 121; and the second end of the third relay 121 is grounded.

[0048] The amplification circuit 122 amplifies the target voltage signal, and the integration circuit 123, as a feedback loop of the amplification circuit 122, integrates the voltage amplified signal in real time to obtain the direct current signal in the voltage amplified signal. Then, the third relay 121 controls whether the direct current signal is fed back to the input end of the amplification circuit 122 by receiving the level state of the coupling selection signal, thereby controlling the target coupling mode corresponding to the target voltage signal, which includes the direct current coupling mode or the alternating current coupling mode, depending on the conduction path of the third relay 121. For example, when the coupling selection signal is a high-level signal, the third end of the third relay 121 is connected to the first end, at this time, the alternating current coupling mode, the second end of the amplification circuit 122 is connected to the first end of the integration circuit 123 through the third relay 121, and the direct current signal output by the integration circuit 123 can be fed back to the second end of the amplification circuit 122 to offset the direct current component in the voltage amplified signal, thereby obtaining the target voltage signal which is an alternating current signal and amplified. When the coupling selection signal is a low-level signal, the third end of the third relay 121 is connected to the second end, at this time, the direct current coupling mode, the second end of the amplification circuit 122 is grounded through the third relay 121, and the direct current component in the voltage amplified signal is not offset, thereby obtaining the target voltage signal which is amplified and has a direct current component, and transmitting the amplified target voltage signal to the input end of the analog bandwidth selection circuit 130 of the next stage.

[0049] Optionally, the analog bandwidth of the integration circuit 123 is less than 1 Hz, so that the high-pass low-frequency cutoff frequency in the alternating current coupling mode is less than 1 Hz, which can ensure smaller top drop when measuring a wide pulse signal. The amplifier in the coupling selection circuit 120 can be OP275, which has a stable unit gain and a voltage noise density less than 6 nV√Hz.

[0050] Further, the analog bandwidth selection signal includes a bandwidth selection sub-signal and an output control sub-signal. The analog bandwidth selection circuit 130 includes a first relay 131, a second relay 132, a first bandwidth branch 133, and a second bandwidth branch 134, wherein: The first bandwidth branch 133 and the second bandwidth branch 134 are connected in parallel, and the first relay 131 and the second relay 132 are respectively arranged at both ends of the parallel circuit corresponding to the first bandwidth branch 133 and the second bandwidth branch 134; The bandwidth selection sub-signal is used to switch the conduction path of the first relay 131 to determine a target bandwidth branch from the first bandwidth branch 133 and the second bandwidth branch 134; the target bandwidth branch is used to filter a target voltage signal received by the first relay 131 to obtain a filtered signal; and the output control sub-signal is used to switch the output path of the filtered signal, and the conduction paths of the first relay 131 and the second relay 132 are the same.

[0051] Specifically, Figure 4 is a structural schematic diagram of an analog bandwidth selection circuit provided by an embodiment of the present application, as Figure 4 indicated, the analog bandwidth selection circuit 130 includes a first bandwidth branch 133 and a second bandwidth branch 134 which have the same structure but different parameters, the bandwidth of the first bandwidth branch 133 is 35 Hz of low noise and high signal-to-noise ratio, and the second bandwidth branch 134 is 700 KHz of full bandwidth. Both bandwidth branches are four-order Bessel low-pass filters, although the frequency response is slow and the decay edge is not steep enough, but has very excellent phase response, and the group delay time of the entire same frequency band is also constant, which can well control the dispersion distortion of the current charge converter and ensure the distortionless conversion of the signal. By controlling the conduction paths of the first relay 131 and the second relay 132, the corresponding target bandwidth branch can be selected. After obtaining the filtered signal, the filtered signal can be output to the output driving circuit 140 in the rear stage.

[0052] Alternatively, the first bandwidth branch 133 can be a four-order Bessel filter, the cutoff frequency of which is 35 Hz, the stop band is 180 Hz@-40dB, the in-band group delay time is 9.6ms, the active amplifier can be ADA4511, and the total noise of the entire amplifier is less than 12μVrms. The second bandwidth branch 134 can be a four-order Bessel filter, the cutoff frequency of which is 750 KHz, the stop band is 4MHz@-40dB, the in-band group delay time is 448ns, the step response rising edge is less than 470ns (10%-90%), and the active amplifier can be AD8022, which can achieve an output noise coefficient of <5nV / √Hz.

[0053] Alternatively, the first relay 131 and the second relay 132 can both be AGN20006, the on-off states of the first relay 131 and the second relay 132 are the same, and the first relay 131 can control whether the amplified target voltage signal is input to the first bandwidth branch 133 or the second bandwidth branch 134 to control the noise control effect in the filtered signal. The second relay 132 is used to ensure the normal output of the filtered signal.

[0054] Further, Figure 5 is a structural schematic diagram of an output driving circuit provided by an embodiment of the present application, asFigure 5 As shown, the conversion circuit 100 further comprises an output driving circuit 140, an input end of the output driving circuit 140 is connected with an output end of the analog bandwidth selection circuit 130, and an output end of the output driving circuit 140 is connected with a collection device, and the output driving circuit 140 is used for power amplification of the filtered signal to obtain a target output signal.

[0055] Specifically, the current charge converter is generally operated in a radiation dose area for a long time, and the current charge converter and the backend electronics are connected through a long distance radio frequency cable, and generally, the length of the radio frequency cable reaches tens of meters to hundreds of meters, therefore, the output driving circuit 140 is further arranged at the rear stage of the analog bandwidth selection circuit 130. The gain of the output driving circuit 140 is 1, the filtered signal is power amplified through the output driving circuit 140 to obtain a target output signal, and the target output signal is sent to the collection device at the backend for visualization, so as to facilitate intuitive observation.

[0056] Optionally, the output driving circuit 140 can be a voltage follower or a large current output amplifier, the large current output amplifier can realize a maximum output current of 380 mA, a GBW of 12 MHz and a voltage rate of change of 24V / μs, and can guarantee output driving of a radio frequency cable of hundreds of meters.

[0057] Further, Figure 6 is a structural schematic diagram of a self-checking logic module provided by an embodiment of the present application, the self-checking logic module 200 comprises a self-excited oscillator 210, a voltage-current conversion unit 220 and an output interface 230, wherein: The self-excited oscillator 210 is used for generating a self-checking pulse signal with a fixed frequency in a self-checking mode; The voltage-current conversion unit 220 is used for converting the self-checking pulse signal into a self-checking current signal; The output interface 230 is used for sending the self-checking current signal to an input end of the signal conversion circuit 110.

[0058] Specifically, the self-checking logic module 200 includes a monostable self-oscillator 210, which can output a self-checking pulse signal in the range of 0-10V voltage, with a fixed frequency of 10Hz and a pulse width of 100us, which can be a square wave pulse signal, after a timed or untimed trigger self-checking mode. Then, the voltage-to-current conversion unit 220 can be a structure based on the Howland circuit, which can convert the self-checking pulse signal into a self-checking current signal, and the conversion coefficient can be realized by feedback proportion and output sampling resistance. In the embodiment of the present application, the conversion coefficient of the voltage-to-current conversion unit 220 is 100k, that is, a self-checking current signal in the range of 0-100uA current and with a fixed frequency of 10Hz is obtained. Then, the self-checking current signal can be output to the input end of the signal conversion circuit 110 by the output interface 230, and then sequentially pass through the signal conversion circuit 110, the coupling selection circuit 120, the analog bandwidth selection circuit 130 and the output driving circuit 140 for signal conversion, and output the converted signal to the acquisition device to determine whether the working state of the current charge converter is abnormal.

[0059] Further, Figure 7 is a structural schematic diagram of the control logic module provided by the embodiment of the present application, as Figure 7 shown, the current charge converter further includes a control logic module 300, the control logic module 300 includes a local control unit 310, a remote control unit 320 and a multiplexer 330, wherein: The local control unit 310 or the remote control unit 320 is used to determine a target relay operating signal in response to user operation; the target relay operating signal includes: a target gain gear signal, an analog bandwidth selection signal or a coupling selection signal; The multiplexer 330 is used to send the target relay operating signal to the corresponding target relay to drive the target relay to act based on the signal source of the target relay operating signal.

[0060] Specifically, the control of each relay in the embodiment of the present application has two independent control modes, which are local control mode and remote control mode. When the current charge converter is arranged in an area with a large radiation dose, the remote control mode can be used. When the current charge converter is arranged in an area with a small radiation dose, the local control mode can be used.

[0061] In the control logic module 300, local control can be performed through the local control unit 310. The local control unit 310 is provided with a 6-segment rotary switch corresponding to the signal conversion circuit 110, and a toggle switch corresponding to the coupling selection circuit 120 and the analog bandwidth selection circuit 130. The 6-segment rotary switch includes five gain gears and a gain (RM) key. In the default state, the 6-segment rotary switch points to the gain key. Different positions of the toggle switch correspond to different level states of the signal. After the user operates the 6-segment rotary switch or any toggle switch, a control signal of the corresponding relay can be generated to control the action of the relay. For example, when the user rotates the 6-segment rotary switch to 10 3 When the gain gear is set, the target gain can be generated to 10 3 The target gain gear signal can be output through the corresponding output line in the multiplexer 330 to the open-drain drive circuit of the relay in the gain gear circuit 111 with a conversion resistance of 100Ω in the signal conversion circuit 110 to drive the relay to operate and control the relay to switch from the open state to the closed state.

[0062] In the control logic module 300, remote control can be performed through the remote control unit 320. The remote control unit 320 is provided with a remote control interface, which can be an 8-core Lemo interface. After the user generates a remote signal in the remote device, the remote signal can be sent to the remote control interface through the remote controller in the remote device, enter the current-to-charge converter, undergo magnetic coupling isolation to reduce coupling noise, and then connect to the conversion circuit 100.

[0063] Optionally, the multiplexer 330 may be a 2-input multiplexer 74HC157 for selecting a source of a control signal.

[0064] Furthermore, the current-to-charge converter further includes a protection logic module 400. Figure 8 FIG. 1 is a schematic diagram of the structure of the protection logic module provided by an embodiment of the present invention. Figure 8 As shown, the protection logic module 400 includes a signal coupling unit 410, an absolute value calculation unit 420 and a threshold comparison unit 430, wherein: The signal coupling unit 410 is configured to receive the amplified target voltage signal output by the coupling selection circuit 120; The absolute value calculation unit 420 is used to invert the negative signal in the amplified target voltage signal to obtain an inverted voltage signal; The threshold comparison unit 430 is used to compare the inversion voltage signal with the voltage threshold to obtain a voltage comparison result.

[0065] Specifically, after the amplified target voltage signal is output by the coupling selection circuit 120, the signal coupling unit 410, which is a high input impedance unit gain in-phase amplifier, is further sent to the signal coupling unit 410 to pick up the amplified target voltage signal. The absolute value calculation unit 420 can be an active precision rectifier. Through the absolute value calculation unit 420, the negative signal in the amplified target voltage signal can be flipped to obtain a flipped voltage signal. The threshold comparison unit 430 can be a comparator, and the flipped voltage signal can be output to one of the input terminals of the threshold comparison unit 430, and the flipped voltage signal is compared with the voltage threshold of the other input terminal to obtain a voltage comparison result. The voltage threshold can be set to 120% of the maximum output voltage, for example, the voltage threshold can be set to 12V. If the voltage comparison result is that the flipped voltage signal is greater than the voltage threshold, an alarm signal can be generated. The alarm signal can be output to the indicator light, remote control device or acquisition device for alarm to remind the operator to check.

[0066] Further, the current charge converter further comprises a power module 500, Figure 9 is a structural schematic diagram of the power module provided by the embodiment of the application, as Figure 9 indicated, the power module 500 is used to supply power to the devices in the current charge converter.

[0067] Specifically, the input of the power module 500 is a 5-core Lehner interface, and the voltage specification is ±18V and 8V. The input end of the power module 500 can be connected to a level converter, and the level converter can convert the mains 220V into ±18V and 8V. The power module 500 comprises an analog power conversion unit 510 and a digital power conversion unit 520. The analog power conversion unit 510 can adopt a TPS7A4700 converter and a TPS7A3301 converter. The TPS7A4700 converter can convert +18V into +15V and +5V, and the TPS7A3301 converter can convert -18V into -15V and -5V, and the voltage conversion process power noise is as small as possible, realizing the supply of the supply rail ±15V and the supply of the amplifier in the signal conversion circuit 110. The supply voltage of the logic device and the relay device in the digital part is 5V, therefore, the digital power conversion unit 520 can adopt an LT1083 converter to realize the voltage conversion from 8V to 5V.

[0068] In addition, a low-noise current signal source is used as an input source, and an oscilloscope is used as an output end acquisition device to test the bandwidth and dynamic range of the current charge converter in the embodiment. That is, the output mode of the low-noise current signal source is set to 5Hz sinusoidal alternating current, the current source output value is increased point by point from 10pA to 10mA, and the corresponding gain position of electronics is selected. The oscilloscope is used to measure the effective value of the alternating voltage output by the current charge converter, and the dynamic range and linearity error of the electronics are obtained according to the point scanning results. The test results are shown in FIG. 5. Figure 10 In addition, the output mode of the low-noise current signal source is set to 2mA sinusoidal mode, the minimum gain of the measured converter is set to 10^3 mode, the initial frequency of the current source is set to 10Hz, the output amplitude of the current source is fixed, and the output frequency of the signal source is increased point by point. When the converter output amplitude is 0.707 times the passband voltage, it is the -3dB frequency point, that is, the system bandwidth. The test results are shown in FIG. 6. Figure 11

[0069] The current charge converter provided by the embodiment has a preset gain range of 10 3 to 10 10 , a super-wide dynamic range, and can realize signal conversion of extremely weak current charge signals in the range of 10mA to 10pA. In combination with the noise control of the analog bandwidth selection circuit on the converted target voltage signal, the obtained filtered signal has a wide analog bandwidth and a low noise level, ensuring distortionless conversion of the signal. In addition, the self-checking logic module is used for self-checking and self-testing, and the working state of the entire converter is detected in real time.

[0070] The embodiment further provides an accelerator beam diagnosis system, which comprises an acquisition device and the current charge converter according to any one of the above. The output end of the current charge converter is connected to the input end of the acquisition device, and the current charge converter is used to send a target output signal to the acquisition device for visualization.

[0071] ​It should be pointed out finally that the above embodiments are only used to illustrate the technical solutions of the present application, but not to limit the same; and although the present application has been described in detail with reference to the foregoing embodiments, it should be appreciated by those skilled in the art that the technical solutions recorded in the foregoing embodiments can be modified, or some technical features thereof can be replaced equivalently; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present application.

Claims

1. A current-to-charge converter, characterized in that: include: Conversion circuit and self-test logic module, including: The conversion circuit includes a signal conversion circuit and an analog bandwidth selection circuit. The signal conversion circuit is used to receive a current charge signal and a target gain gear signal, and based on the target gain gear signal, convert the current charge signal into a target voltage signal under a corresponding gain; the target gain gear signal is determined from a preset gain range corresponding to the signal conversion circuit, and the preset gain range is 10 3 to 10 10 The analog bandwidth selection circuit is used to perform noise control on the target voltage signal based on the analog bandwidth selection signal to obtain a filtered signal; The output end of the self-test logic module is connected to the input end of the conversion circuit. The self-test logic module is used to generate a self-test current signal with a fixed frequency in a self-test mode, and output the self-test current signal to the conversion circuit for self-test.

2. The current-to-charge converter according to claim 1, wherein: The signal conversion circuit includes a plurality of gain gear circuits and feedback amplifiers connected in parallel; A plurality of gain level circuits connected in parallel are connected in parallel between the inverting input terminal and the output terminal of the feedback amplifier; When the control end of the target gain gear circuit receives a target gain gear signal, the feedback amplifier is used to convert the received current charge signal into a target voltage signal under the gain corresponding to the target gain gear circuit; the target gain gear circuit is any one of multiple gain gear circuits.

3. The current-to-charge converter according to claim 1, wherein: The analog bandwidth selection signal includes a bandwidth selection sub-signal and an output control sub-signal; The analog bandwidth selection circuit includes a first relay, a second relay, a first bandwidth branch and a second bandwidth branch, wherein: The first bandwidth branch and the second bandwidth branch are connected in parallel, and the first relay and the second relay are respectively provided at two ends of the parallel circuit corresponding to the first bandwidth branch and the second bandwidth branch; The bandwidth selection sub-signal is used to switch the conduction path of the first relay to determine a target bandwidth branch from the first bandwidth branch and the second bandwidth branch; the target bandwidth branch is used to filter the target voltage signal received by the first relay to obtain a filtered signal; the output control sub-signal is used to switch the output path of the filtered signal, and the conduction paths of the first relay and the second relay are the same.

4. The current-to-charge converter according to any one of claims 1 to 3, wherein: The conversion circuit further includes a coupling selection circuit, which includes a third relay, an amplifying circuit, and an integrating circuit, wherein: The amplifier circuit is used to amplify the received target voltage signal to obtain a voltage amplification signal; The integration circuit is used to integrate the voltage amplification signal to obtain a DC signal; The control end of the third relay is used to receive a coupling selection signal, and the level state of the coupling selection signal is used to control the conduction path of the third relay to control whether the DC signal is fed back to the input end of the amplifier circuit to obtain an amplified target voltage signal, and send the amplified target voltage signal to the input end of the analog bandwidth selection circuit.

5. The current-to-charge converter according to claim 4, wherein: The conversion circuit also includes an output drive circuit, the input end of the output drive circuit is connected to the output end of the analog bandwidth selection circuit, and the output end of the output drive circuit is connected to the acquisition device. The output drive circuit is used to power amplify the filtered signal to obtain a target output signal.

6. The current-to-charge converter according to any one of claims 1 to 3, characterized in that: The self-test logic module includes a self-excited oscillator, a voltage-current conversion unit and an output interface, wherein: The self-excited oscillator is used to generate a self-test pulse signal with a fixed frequency in a self-test mode; The voltage-current conversion unit is used to convert the self-test pulse signal into a self-test current signal; The output interface is used to send the self-test current signal to the input end of the signal conversion circuit.

7. The current-to-charge converter according to claim 4, wherein: The system further comprises a control logic module, wherein the control logic module comprises a local control unit, a remote control unit and a multiplexer, wherein: The local control unit or the remote control unit is used to respond to user operations and determine a target relay operation signal; the target relay operation signal includes: a target gain gear signal, an analog bandwidth selection signal or a coupling selection signal; The multiplexer is configured to send the target relay operation signal to the corresponding target relay based on a signal source of the target relay operation signal, so as to drive the target relay to operate.

8. The current-to-charge converter according to claim 4, wherein: It also includes a protection logic module, which includes a signal coupling unit, an absolute value calculation unit and a threshold comparison unit, wherein: The signal coupling unit is used to receive the amplified target voltage signal output by the coupling selection circuit; The absolute value calculation unit is used to invert the negative signal in the amplified target voltage signal to obtain an inverted voltage signal; The threshold comparison unit is used to compare the inversion voltage signal with the voltage threshold to obtain a voltage comparison result.

9. The current-to-charge converter according to claim 4, wherein: A power supply module is also included, for supplying power to the devices in the current-to-charge converter.

10. An accelerator beam diagnosis system, characterized in that: The device comprises an acquisition device and a current-to-charge converter according to any one of claims 1 to 9, wherein: The output end of the current-to-charge converter is connected to the input end of the acquisition device, and the current-to-charge converter is used to send the target output signal to the acquisition device for visualization.

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