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In Tokamak device, many larger capacity pulsed power supplies have been installed to provide high-energy magnetic field to control plasma. In this article, a new digital control system for satisfying larger capacity pulse power supply is introduced. This control scheme uses programmable automation controller (PAC) architecture, which consists of software platform and hardware platform to design a new digital control system, and in this system, real-time operation system (OS) and real-time communication network can provide much more precise and predictable timing characteristics to fulfill the requirements of the real-time control for pulse power supply in Tokamak device. Its hardware architecture based on integration and modularization can provide reliability, stability, and flexibility for digital control application; meanwhile, its software platform is used to handle data communication, close-looping control, protection strategy execution, and trigger output. After the digital control system of the large-capacity pulse power supply is built, its performance is verified through the HL-2A experiments. The result shows that the digital control system achieves the design goals and has high reliability and stability.

The power supply control system is one of the most important local control systems of HL-2M tokamak. The power supply system of HL-2M is composed of four flywheel generator sets with total capacity of 600 MVA, all the magnetic field coil power supplies and high voltage power supplies of auxiliary heating system. The control system of power supply should make sure the large amount of on-site equipment and facilities to operate steadily and reliably. This paper presents the architecture of HL-2M control system and four kinds of established control networks. It describes how the power supply control system is built by using the established hardware structures and software agreements. Specially, it is focused on introducing an application of real-time technology based on the reflective shared memory and the fully digital compact solution for controlling the high power converters. Otherwise, a scheme which adopts PROFINET and Sequence of Events technology to carry out the intellect interlock control system is given.

The high voltage power supply (HVPS) based on pulse step modulation (PSM) has already been developed for the auxiliary heating system on HL-2A. This power supply consists of many switch power supplies, and its output voltage can be obtained by modulating their delay time and pulse widths. The PSM topology and control principle are presented in this paper. The simple algorithms for the control system are explained clearly. The switch power supply (SPS) module has been built and the test results show it can meet the requirements of the auxiliary heating system. Now, 112 SPS modules and the whole system have already been developed. Its maximum output is about 72 kV/93 A. The protection time is less than 5 μs. The different outputs of this power supply are used for the electron cyclotron resonant heating (ECRH) system with different duty ratios. The experimental results of the entire system are presented. The results indicate that the whole system can meet the requirements of the auxiliary heating system on HL-2A.

The load of the 125 MVA motor generator on the HL-2A tokamak is introduced. The frequency of harmonics on the output current is analyzed, and the analysis result is verified by Fourier decomposition of the measured signal. The variable harmonic and reactive currents through the power lines of the generator are figured out using its phase voltage and currents. The simulation results are helpful to the R&D of the active power filter for the 125 MVA generator.

The highpower pulsed power supply system for the magnetic field of the HL-2A Tokamak is described in this paper. The total output power of its eight magnetic field power supply units of nearly 250 MW. Their highest DC output voltage and current are 3510 V and 45 kA, respectively. All the units are operated in a pulsed mode. The pulse duration is 5 s, and the cyclic period is 15 min. The power supply system consists mainly of pulsed flywheel motor generators, rectifying transformers, thyristor converters, diode rectifiers and switches. The system incorporates many key technologies?supply equalization with two generators and four diode bridges, constant-angle phase triggers with a wide frequency range, current equalization, a status detector for the high current 6-phase converter, and advanced monitoring based on a programmable logic computer and engineering parameter measurement. The experimental results show that the performance of the power supply system satisfies the requirements of HL-2A experiments very well.

Each magnetic field power supply is consists of three-phase full bridge thyristor converters on HL-2A Tokamak. To enhance and improve the performance of the control system of power supply system, a varying frequency three phase signal circuit has been design based on digital signal processor, which was used to control power supply on HL-2A Tokamak. This synchronous system has many advantages and is successfully applied to the operation of the power supply system in plasma discharge.

HL-2A tokamak operation needs several pulse DC power supplies with peak power of 300 MVA and the energy content of 1200 MJ per shot. To meet this requirement, three flywheel motor-generators (MG) are used, and the diode and thyristor AC/DC converters are developed to power the HL-2A toroidal and poloidal field coils. A new control system of the power supply is implemented. The power supply system is put into operation. The design and development of this power supply system are presented.

in the large fusion devices HL-2A, HVPS based on pulse step modulation (PSM) technique and IGBT has many advantages, but it has the characteristics of poor electromagnetic environment, fast rise time and high-frequency components. According to the power characteristics, the measurement systems need to not only monitor the system power supply waveform, but also provide real-time data which is used to the detection system and the control system. In order to meet the requirement, the measurement system must have fast response and good anti-interference ability. In the measurement system, voltage divider is a crucial portion which contributes to measurement performance. A kind of proper divider parameter is designed. The divider has high fidelity by contrast and calibration test. For the divider, the bandwidth is about 500 kHz. The response time is less than 2µs. Meanwhile signal isolation transmission is adopted for high voltage signal. The transmission of analog signal adopts the technology of Voltage control oscillator (VCO) which shows better linearity, wide bandwidth(500KHz), fast response(less than 2µs), temperature insensitive, anti-interference ability and response time. This measurement system is proved effective by experiments. Meanwhile, the practical value is extensive.

The load of 125MVA motor generator on HL-2A is introduced. The frequency of harmonics on the output current is analyzed and it is verified by Fourier decomposition to measured signal. The harmonic current and reactive current on power line of generator are calculated from its phase voltages and currents. The simulation results are helpful for the study of active power filter for 125MVA generator.

A high-voltage power supply with an output of 80 kV/200 A has been built with pulse step modulation (PSM) technology to energize the gyrotrons of the electron cyclotron resonance heating (ECRH) system on HL-2A Tokamak. To improve the performance of the control system of the PSM system, a fully digital controller based on digital signal processor and field-programmable gate arrays has been developed. This controller has many advantages and is successfully applied to the operation of the PSM system in ECRH experiment.