Applicability of Rapid Control Prototype (RCP) Products
In the development and production of controllers, conventional development methods for independently manufacturing PCB control boards that are based on DSP chips have many problems, such as long cycles and the poor reliability of the independently produced hardware. As a highly efficient R&D tool, an RCP can be used to reduce the time users spend in code translation, hardware customization, debugging during the development or learning stage. The joint debugging and testing of the actual object can be controlled after the rapid download of the algorithm through the rapid control prototype simulator.
Compared with the traditional method of downloading the algorithm to the control board through C language after offline digital simulation, the RCP method has the following advantages:
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Easy deployment: Users can deploy the control algorithm directly, reducing the burden of low-level development.
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Easy joint-debugging: Through real-time monitoring and online parameter adjustment, the problems existing in the control algorithm can quickly be identified.
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High flexibility: With strong platform performance and rich resources, the research and development needs of multiple projects can be met.
Core Metrics of RCP Products
At present, there are many rapid control prototype (RCP) products on the market, from both domestic and foreign brands. There are RCP controllers based on CPU+FPGA architecture, and also RCP controllers based on DSP, with characteristics and methods of use varying from manufacturer to manufacturer. How can users choose the right RCP product? What are the key metrics of HIL products that users need to pay attention to? The following is a brief overview of key points that users need to pay attention to when evaluating RCP products.
Functional Metric 1: the number of IO ports
RCP products are primarily used as controllers, so a rather important metric is the number of data acquisition interfaces (AD) and digital outputs (PWM). When evaluating products for purchase, users must consider the number of interfaces needed in relation to the system they need to control and allowances. Some RCP products support interface expansion or cascading, which allows for improved scalability.
Indicator |
Evaluation criteria |
Number of IO |
IO quantity meets control requirements |
Scalability of IO |
We recommend selecting products with IO scalability to provide possibilities for complex applications and future upgrades. |
IO expansion based on DSP or PCI bus |
High latency, weak synchronization performance, not suitable for control above 10K. |
IO expansion based on fiber optic synchronization |
Delay at the nanosecond level, excellent synchronization performance, suitable for high-speed power electronics control. |
Functional Metric 2: the operating speed of the algorithm
Another important metric for evaluating RCP products is how fast the algorithm can run after loading. In terms of method of use, most RCP products run the users' algorithm codes on the CPU cores of RCP products after generating them. Therefore, the operating speed of the algorithm reflects the CPU capacity of RCP products and the level of product software optimization. At the same time, overly complex algorithms may not run as fast as expected on RCP products, which is also a matter that users need to pay attention to during evaluation.
Indicator |
Evaluation criteria |
CPU clock frequency of the product |
It is not recommended to evaluate the computational capability solely based on the CPU clock frequency of RCP products. The computational capability is also related to the hardware capability of the CPU and system optimization ability. |
"Rate (step size) of algorithm execution |
It is meaningless to solely rely on the minimum step size claimed by the product. It is recommended to evaluate the computational rate of RCP products based on the complexity level of algorithms required by the user. |
Stability of computations |
Only controllers that can run stably can ensure good control effects. It is recommended to use products that can display algorithm execution delays, which can help users monitor the running status in real time. |
Functional Metric 3: control program compatibility
Since RCP products are mostly designed to reduce the time spent by users on low-level programming and are tools to improve efficiency, users need to consider the algorithm writing environment supported by RCP products according to their actual development conditions when evaluating RCP products. Mainstream RCP products support users in writing freely based on Simulink, and some do not support users in writing freely, but need to use the library model provided by the product to complete code generation; Moreover, some products only support environments other than Simulink, such as PSIM, LabVIEW, etc.
Indicator |
Evaluation criteria |
Support free coding based on Simulink |
Simulink is a mainstream environment for building control algorithms, so it is recommended to use RCP products that support users to freely build control algorithms. |
Don't support free coding based on Simulink |
Some RCP products that claim to support Simulink do not support commonly used Simulink modules. They require the installation of specific function libraries, which comes with significant limitations. Therefore, it is not recommended. |
Don't support Simulink environment |
Some RCP products only support their own algorithm development environments, such as PSIM, LabVIEW, etc. If users are not familiar with these environments, the learning curve and transition cost can be high. Therefore, it is not recommended. |
Functional Metric 4: PWM and other functional modules
In addition to running the core algorithm, some functional modules require high-speed and high-precision operation in the implementation of RCP products; such as PWM generation and position signal decoding. If these functional modules are weak, the results under high-speed control will be impacted. Mainstream RCP products employ CPU + FPGA operation architecture, and will implement modules with high computing requirements on FPGAs. However, due to the particularity of some controls, these functional modules may not be implemented in RCP products, such as the functions of dynamic adjustment of carrier phase and frequency in phase-shifting controls, the function of position signal decoding in special motors, unique PWM wave generation methods, etc. Users, in accordance with their actual needs, must evaluate whether corresponding RCP products have such functional modules, and whether support is available for customization or secondary development for special requirements.
Indicator |
Evaluation criteria |
Module support capability (based on DSP architecture) |
This type of RCP product has relatively weak performance and is slower in waveform generation and signal analysis. It is not suitable for control applications above 10k. |
Module support capability (based on CPU+FPGA architecture) |
This type of RCP product implements carrier generation, signal modulation, and position signal analysis functions on FPGA. It has fast speed and high accuracy, making it the mainstream product architecture currently. |
Module support capability (openness of functional modules) |
The dynamic adjustment of carrier phase and frequency for certain special control requirements, as well as special PWM generation functions, are not included in the standard RCP product modules. It is recommended to use products that support customized module development or secondary development to enhance scalability. |
ModelingTech's RCP Products
ModelingTech's independently developed StarSim RCP products enable users to complete the rapid deployment of control algorithms. With simple configuration through StarSim RCP software, users can download the control algorithm models written in Simulink or LabVIEW and run them on real-time hardware devices, and then debug them through customized operation monitoring interfaces, thus helping users quickly verify the effectiveness of the control algorithm.
ModelingTech can provide domestic leading and international advanced RCP products that are highly cost-competitive, and can also provide physical hardware-platform integrated RCP package solutions. Compared with HIL products, RCP products have higher requirements for support services and rapid response in use. In this respect, ModelingTech has always been at the forefront of the industry and garnered praise from users.
Indicator |
ModelingTech's StarSim RCP Platform |
Number of IO ports |
Supports interface expansion based on fibei-optic synchronization, in addtion to standard IO interface configurations |
Algorithm operating speed |
Maximum algorithm operating speed for the entire product series is not less than 20kHz |
Control program compatibility |
Supports the Simulink algorithm writing environment and requires no additional software installation |
PWM and other functional modules |
Supports the adjustment of carrier phase and frequency and the decoding of multiple position signals, and supports customized development |
Summary
Hardware-in-the-loop (HIL) and rapid control prototype (RCP) products are utilized in the R&D of power electronic system products. They can effectively optimize the system design and accelerate the development of controllers, and are powerful tools for modern enterprises to improve efficiency and promote production. With the continuous development of power and power electronics technology, as well as the continuous progress of computer software and hardware technology, it is believed that real-time simulation tools such as HIL and RCP will have more powerful functions and easier methods of use, and will also play a greater role in the R&D and testing of power electronics products.
