How to select power supplies for peak load applications
CONTENT:
Peak load is an important aspect to consider, as this defines the set period of time when electricity is required to sustain a device on demand. In terms of power consumption, considering the peak load of a device is particularly important for those industries - like manufacturing - with energy-intensive equipment and operations.
Oftentimes, a system or device might need higher power for a very short duration but still be able to operate under a slightly lower power threshold. This way, by using a 200W power supply that can support 300W+ as a peak load, engineers can control the costs associated with investing in more powerful and power-consuming converters.
Considering the particularity of peak load applications, below, we will review more details on a series of aspects to consider for selecting the right power supplies for a similar project.
Dual rated power supplies can offer a smaller, lighter, lower-cost solution without compromising performance, reliability and service life of the end application.
Criteria for Selecting Power Supplies for Peak Load Applications
Selecting a power supply with peak power capability is particularly recommended for inductive loads, where a motor, relay, contractor or other pieces of equipment require high current at start-up. Some examples of similar applications with typically higher peak loads include but are not limited to industrial control cabinets, smart access control systems, and control panels of certain white goods appliances.
In these applications, a piece of equipment or appliance might need to draw short peak currents from the power supply. Under these circumstances, the capacitor basically acts as a short-circuit when faced with the sudden application of voltage at start-up. As a consequence, the risk is to incur the effects of an output voltage drop and other forms of voltage fluctuations that could negatively affect the performance of the power supply.
Besides these risks, system designers are often faced with other challenges, including a limited budget or stringent safety requirements for the intended application. Engineers also have to deal with limitations on the physical space available within the machine.
One possible solution to deal with peak current events is to add current-limiting resistors in series with the capacitive load to set a limit to the output current. Another more viable option is to select power supplies with special overload protection.
Power supplies with enhanced peak power capabilities can not only prevent transient overpower scenarios, especially in inductive load applications. Power supplies for peak load applications can also prevent load spikes from damaging the supply, while also ensuring higher savings without having to compromise the reliability of the system. The reason is that the average power will be lower than the peak demand. For this reason, by using a power supply that can handle peak loads but with a lower power rating, engineers can employ a smaller power supply while also reducing the weight, cost, and system size of their circuits.
Below are some of the other aspects that electrical designers should consider before selecting peak load application power supplies:
● The duty cycle
Before selecting a power supply, engineers can first calculate the approximate on/off time of the machine or equipment to be powered. The on-time will be considered as a proportion of the total cycle time. The duty cycle of a peak load is an important factor that can impact the thermal response of the power supply.
● The average power requirements
The average power requirements of a machine or equipment is another important factor to consider for selecting a cost-effective power supply. When it comes to these criteria, engineers are faced with at least two options. They can either look for power supplies with separate ratings for convention cooling and forced air cooling. The other option is to look for power supplies that are designed specifically to cater to applications with high peak loads. The peak power rating of a power supply is typically 100% more than the average power rating. For this reason, the second option is definitively to be preferred, as power supplies designed for peak load applications have adequate thermal design and overload protection that can anticipate the peak power demand.
● The overcurrent tolerance
Most power supplies are designed with an output overcurrent detection and protection for protecting their internal circuit from damage in the event of excessive load currents. Selecting a power supply that is designed with a high overcurrent tolerance is particularly advantageous when dealing with loads with a crest factor that is greater than 1.8, both in terms of cost and size.
In summary, selecting a peak load power supply rather than one continuously rated for the full peak power results in a smaller, lighter, lower-cost solution without compromising the performance, reliability, and lifetime of the end application. The benefits are clear both in terms of convenience and performance. Some of our power supplies come with a peak power capability that makes them suitable for peak load applications.
MORNSUN's Power Supply Solutions
Engineers need to find ways to optimize the costs and physical size when selecting power supplies for a load with peak demands. Besides the criteria mentioned above, careful component selections is another important stage in electric circuit design for peak load applications.
Engineers should select power solution providers with a wide experience and power module portfolio. MORNSUN can meet both requirements with its wide selection of power supplies that have already been used in all environments across the world for more than 23 years. The MORNSUN power supply solutions include several power module series designed precisely for meeting peak load demands and certified in accordance with the industry standards for most applications.
From AC/DC and DC/DC converters to IGBT drivers and other electrical components, MORNSUN has most of your needs covered with a wide collection of reliable, high-performing, secure power modules. Contact us to ask us any questions or to request a sample of our power supplies for peak load applications.
