The increasing complexity of embedded systems within battery management necessitates robust testing methodologies that accurately reflect real-world operating conditions. Mike Sandoval, vice president business development at Maccor, elucidates the fundamental principles of hardware- in-the-loop (HiL) testing and explores its practical applications in the development and rigorous validation of advanced battery management systems.
The continuous pursuit of safer, more cost-effective, and accelerated testing methodologies remains a primary driver for laboratory investments in cutting-edge testing technologies. Traditionally, the cornerstone of minimising total cost of ownership and operational downtime has been the deployment of robust and reliable test equipment.
However, as battery technology advances and applications become more demanding, hardware-in-the- loop (HiL) testing has evolved into an indispensable tool for comprehensively evaluating the performance of intricate systems, especially in scenarios where real-world testing presents inherent risks, prohibitive costs, or practical limitations.
HiL testing proves invaluable for systems that intricately integrate both hardware and software components. This methodology involves establishing a dynamic connection between physical hardware and a meticulously crafted simulated environment.
Within this environment, the hardware interacts in real-time with a virtual model representing the broader system. This sophisticated approach empowers engineers to rigorously evaluate performance characteristics, control algorithms, and overall system behaviour within a controlled yet remarkably realistic framework.
In the specific context of battery technology, HiL testing offers profound analytical and validation advantages. It enables the rigorous assessment of both the physical hardware and the embedded software components within battery management systems (BMS).
As embedded systems in contemporary battery-powered devices achieve increasing levels of sophistication, their validation under conditions that closely mirror real-world usage patterns becomes paramount. HiL achieves this by establishing a closed-loop environment where the physical battery– whether a single cell, module, or complete pack– interacts dynamically with a real-time simulation serving as its operational context, often referred to as a ‘digital twin’. This integration facilitates comprehensive verification of control algorithms, system responses, and the fundamental functionality of the hardware itself.
Key applications of HiL testing in the realm of battery systems include:
- Functionality and safety testing: HiL enables the thorough evaluation of core battery management system functions, encompassing voltage and current monitoring, precise temperature control, accurate state-of-charge and state-of- health estimation, and effective cell balancing strategies. By simulating a diverse range of electrical and thermal conditions, engineers can ensure that the battery management system responds appropriately and reliably engages critical safety mechanisms (e.g., over-voltage, under-voltage, over-current, over-temperature protections) as meticulously designed.
- Fault condition simulation: Engineers can strategically simulate various fault scenarios – such as short circuits, open circuits, and sensor failures – to rigorously assess the BMS’s inherent ability to promptly detect and safely manage these abnormal conditions, a critical aspect of ensuring overall system integrity and safety.
- Thermal management system evaluation: By seamlessly integrating a detailed thermal model of the battery pack into the simulation environment, HiL testing can effectively verify the performance of BMS-controlled cooling and heating systems across a wide spectrum of operational demands and ambient temperature variations.
- Charge/discharge control verification: HiL facilitates the comprehensive testing of charging and discharging control strategies under dynamically varying grid demands and the intermittent availability of renewable energy sources, ensuring efficient energy management and grid stability.
- Integration with power electronics: Simulating the intricate interaction between the battery system and power converters (inverters, rectifiers) under diverse grid conditions – including voltage and frequency fluctuations – helps to meticulously validate the seamless integration performance of the entire battery system within its intended application.
- Battery cell characterisation and modelling: HiL can also be strategically employed to validate the accuracy and fidelity of battery cell models by directly comparing simulated results with meticulously collected real- world performance data obtained under identical test conditions, thereby refining the predictive capabilities of the digital twin.
A typical HiL setup involves establishing a precise interface between the battery under test and a sophisticated real-time simulator that accurately emulates the external system environment it would encounter in practical applications. The simulator dynamically provides a stream of input signals to the BMS, meticulously processes its corresponding responses, and seamlessly feeds back outputs to close the control loop. This sophisticated configuration enables thorough and repeatable testing across a broad spectrum of operating conditions, far exceeding the limitations of traditional static testing.
Maccor’s MacNet platform is specifically engineered to empower advanced HiL testing methodologies. Its inherent architecture allows for the dynamic and granular manipulation of test parameters in real-time, enabling the highly accurate emulation of complex and time-varying operational scenarios.
MacNet’s extensive and integrated feature set significantly simplifies the creation and efficient execution of intricate dynamic test protocols, providing engineers with unprecedented precise control and profound insights into the nuanced behaviour of battery systems.
System overview: the evolution of MacNet for HiL testing
Maccor first introduced the MacNet interface in 2015 with the primary objective of providing users with remote access to comprehensive status information emanating from its sophisticated battery test systems. The platform’s core strength lies in its inherent ability to dynamically alter crucial test parameters in real-time based on a diverse range of external inputs or meticulously calculated values. This functionality is paramount for effective HiL testing, enabling the seamless and accurate integration of simulated environmental factors and complex operational profiles directly into the physical battery testing process.
By allowing external parameters to instantaneously dictate new test parameters, MacNet provides the essential agility required to accurately emulate the intricate nuances of real-world applications.
Features and capabilities
MacNet offers a comprehensive and tightly integrated suite of features and capabilities that collectively establish it as an ideal platform for conducting advanced HiL testing of sophisticated battery management systems:
- Real-time monitoring: A comprehensive and granular live monitoring of all active test channels, offering real- time visualisation of critical test parameters.
- Networking and remote access: The network-centric design significantly enhances collaboration and accessibility for distributed teams.
Application scenarios
MacNet’s extensive capabilities within a HiL framework enable a diverse and critical range of testing and development scenarios specifically tailored for advanced battery management systems:
- Monitoring driven by external events: In a typical monitoring- driven scenario, critical battery parameters such as voltage and temperature are continuously observed and analysed by the client software. These monitored values can then be intelligently configured to trigger specific actions or modifications within the active test protocol, effectively mimicking how a sophisticated battery management system would react to dynamic environmental changes or fluctuating operational demands encountered in real-world deployments.
- Developing advanced dynamic charging algorithms: The optimisation of battery charging algorithms represents a pivotal challenge in the ongoing advancement of both portable and stationary energy storage solutions. Intelligent charging algorithms offer a more sophisticated and sustainable solution by dynamically adjusting crucial charging parameters in real-time to achieve rapid charging while simultaneously minimising stress on the battery’s internal components.
- Real-time, real-world applications: It is practically impossible to perfectly replicate the infinite variations of real-world usage profiles within a controlled laboratory setting using traditional static test procedures. While meticulously defined fixed test profiles provide valuable and essential data for largescale, side-by-side comparisons of battery performance under standardised conditions, they often fail to capture the nuanced and dynamic interactions that occur during actual real-world use.
MacNet’s robust architecture allows for the controlled and precise injection of faults or extreme edge-case values directly into the simulation environment, enabling engineers to thoroughly evaluate the robustness and responsiveness of both the battery management system and the overall battery system to unexpected anomalies, ultimately enhancing both the reliability and the inherent safety of the final product.
By effectively leveraging the advanced capabilities of the MacNet platform, developers can significantly accelerate the development of intelligent and adaptive charging algorithms, gain deeper and more nuanced insights into battery performance under dynamic and unpredictable usage profiles, and rigorously evaluate the overall robustness and inherent safety of their battery systems.
As battery technology continues its rapid evolution, MacNet stands as a critical enabler for ensuring the long-term reliability, optimal efficiency, and enhanced safety of next- generation energy storage solutions across a wide range of applications.
