Fuel Cell Cooling Water Flow Control for PEM Hydrogen Fuel Cell Systems

Quick summary This application uses an MVM-020-QA electromagnetic flow meter, an IMI Buschjost 82880 motorized valve and a PID controller to maintain stable cooling water flow in a PEM fuel cell system. The solution compensates for fluctuations in pump pressure and cooling demand, helping improve thermal management and system reliability.

PEM fuel cells operate within a narrow temperature window. If the cooling water flow is too low, excessive heat can reduce efficiency, accelerate membrane degradation and shorten stack lifetime. If the flow is too high, unnecessary pumping power is consumed and overall system efficiency decreases. 

In a real fuel cell cooling loop, flow conditions are constantly changing. Variations in pump pressure, cooling demand and hydraulic resistance can all affect the cooling water flow rate. To maintain a stable flow through the fuel cell stack, active flow control is often required.

In this application example, Bronkhorst High-Tech combined a MAG-VIEW MVM-020-QA electromagnetic flow meter, an IMI Buschjost 82880 motorized control valve and a PID controller to create a closed-loop cooling water flow control system for a fuel cell application.

Understanding PEM fuel cell cooling water flow control

The customer was developing a PEM fuel cell cooling circuit that required stable water flow with minimal pressure loss. The fuel cell requires a constant flow of cooling water to maintain stable operating conditions. In addition, minimizing pressure drop throughout the cooling circuit was critical, requiring a flow control solution with minimal flow resistance.

Application requirements

Flow range	0–12 l/min H₂O at 50–70 °C
Pressure	P1 ≈ 2.5 barg, pressure loss across the cooling circuit must be kept to a minimum.
Water reservoir	Integrated tank with built-in pump

Selected solution

Flow meter	MAG-VIEW MVM-020-QA
Control valve	IMI Buschjost 82880 motorized valve
Controller	PID controller
Feedback signal	4-20 mA feedback loop

The flow meter provides accurate flow measurement and transmits a 4-20 mA (frequency also possible) signal to the controller. This real-time feedback is crucial for maintaining the desired flow setpoint.

Flow valve

The IMI Buschjost 82880 motorized valve acts as the final control element in the cooling loop. Valve position is automatically adjusted by the PID controller based on the flow signal received from the MAG-VIEW flow meter.

Closed-loop cooling water flow control

Unlike a fixed pump configuration, this solution continuously measures actual cooling water flow using the MVM-020-QA electromagnetic flow meter.

The measured flow signal is transmitted to the PID controller via a 4-20 mA signal. The controller compares the measured value with the desired flow setpoint and automatically adjusts the IMI Buschjost motorized valve.

This closed-loop approach compensates for changes in pump pressure, flow resistance and varying cooling demand from the fuel cell stack.

Why precise flow control is critical

Fuel cells operate within tight thermal limits. Effective thermal management and cooling water flow control are essential for maintaining stable stack temperatures, maximizing efficiency and extending fuel cell lifetime. Without accurate control, this leads to:

• Reduced efficiency
• Accelerated membrane degradation
• Lower stack lifetime

Benefits for fuel cell OEMs and system integrators

• Accurate cooling water flow measurement
• Stable thermal management of PEM fuel cells
• Compensation for fluctuating pump pressure
• Fast response to changing operating conditions
• Reduced engineering effort through a proven control architecture
• Scalable solution for test benches and production systems

Bronkhorst High-Tech: building the solution

Bronkhorst High-Tech specializes in combining flow measurement, control technology and communication interfaces into integrated customer-specific solutions. By combining proven components such as electromagnetic flow meters, motorized control valves and PID control electronics, complex thermal management challenges can be solved using a single integrated architecture.

Conclusion: your path to reliable fuel cell cooling

Fuel cells are increasingly used in clean energy and hydrogen applications. By combining flow meters, control valves and intelligent controllers, engineers can ensure optimal performance and long-term reliability.

Looking for a reliable cooling water flow control solution for your fuel cell application?
Explore solutions such as the Bronkhorst flow controller, MVM-020-QA flow meter and IMI Buschjost control valve for precise fuel cell cooling applications.

Need help with fuel cell cooling water flow control? Are you developing a PEM fuel cell system, hydrogen test bench or cooling skid and looking for a reliable flow control solution? Our engineers can help you select the right electromagnetic flow meter, control valve and controller configuration for your application. Discuss your fuel cell cooling application with our engineers.

Key takeaways • Fuel cell cooling is critical for efficiency and durability. • Precise flow control prevents overheating and performance loss. • Closed-loop control improves thermal stability. • Integrating flow meters and valves ensures reliable operation. • Accurate thermal management extends fuel cell stack lifetime.