Well, as I don’t have an in-depth manual, here is what I am going with in terms of required heat dissipation in figuring out how much cooling I need to cool my electric motor controller.
When it comes to cooling an electric motor controller in a marine environment, a marine heat exchanger is a commonly used solution. Marine heat exchangers are designed to transfer heat from a fluid (usually water) to the surrounding environment, providing efficient cooling for various marine applications.
To identify the best marine heat exchanger for your specific needs, consider the following factors:
- Heat Load: Determine the amount of heat that needs to be dissipated from the electric motor controller. This information can usually be found in the controller’s technical specifications or user manual.
- Cooling Capacity: Look for a marine heat exchanger that can handle the heat load of your electric motor controller. The cooling capacity of a heat exchanger is typically specified in terms of BTU (British Thermal Units) or kilowatts.
- Flow Rate: Consider the required flow rate of the cooling water to effectively remove heat from the heat exchanger. The flow rate is usually measured in gallons per minute (GPM) or liters per minute (LPM).
- Space and Installation Constraints: Evaluate the available space and mounting options on your marine vessel to determine the appropriate size and configuration of the heat exchanger.
- Corrosion Resistance: Since marine environments are prone to corrosion, it is crucial to choose a heat exchanger that is resistant to saltwater and other corrosive elements commonly found at sea.
It is recommended to consult with a marine engineer or a knowledgeable professional in the field of marine cooling systems. They can assess your specific requirements, vessel setup, and provide expert advice on selecting the most suitable marine heat exchanger for cooling your electric motor controller.
Northern Comfort’s Vector VEC-500 estimation
While it may not provide precise values, you can estimate the heat dissipation requirements based on the power rating of the motor controller. Electric motor controllers typically have a rated power, given in kilowatts (kW) or horsepower (HP). As a rough approximation, assume that a certain percentage of the rated power is converted into heat. For example, you might estimate that 80% of the rated power is dissipated as heat. From there, you can calculate the approximate heat load that needs to be managed.
To estimate the heat load of your 10 kW BLDC (Brushless DC) electric motor controller, we can make some assumptions based on typical motor controller efficiency and heat dissipation patterns. Keep in mind that these are rough estimations and follow your manufacturer’s advice.
Efficiency: Electric motor controllers generally have efficiency ratings that indicate the percentage of electrical power converted into mechanical power. For estimation purposes, let’s assume an efficiency of around 90%. This means that 10% (1 kW) of the electrical power would be converted into heat.
Heat Dissipation: Typically, a significant portion of the heat generated in an electric motor controller is dissipated through conduction and convection. However, we’ll assume that approximately 70-80% of the heat generated requires active cooling as I don’t have specific manufacturer instructions.
With these assumptions in mind, we can estimate the heat load and size of the heat exchanger:
Heat Load: 10 kW × 0.1 (heat generation factor) × 0.7 to 0.8 (heat requiring active cooling) = 0.7 kW to 0.8 kW of heat load.
Size of Heat Exchanger: The sizing of the heat exchanger depends on factors such as the desired temperature difference, the cooling medium (e.g., water), flow rate, and the specific design of the heat exchanger. As an estimation, a heat exchanger with a cooling capacity of around 1 kW to 1.2 kW should be suitable for dissipating the heat generated by the electric motor controller.
Converting to BTU
To convert the heat load from kilowatts (kW) to British Thermal Units (BTU), we can use the following conversion factor:
1 kW = 3,412 BTU/hr
Using this conversion factor, we can calculate the approximate heat load in BTU:
Heat Load: 0.7 kW to 0.8 kW × 3,412 BTU/hr = 2,388 BTU/hr to 2,729 BTU/hr
So, the estimated heat load of Northern Comfort’s 10 kW BLDC electric motor controller would be approximately 2,700 BTU/hr.
Options
Intending to keep the glycol mixture as fluid 1 flowing through the liquid cooling plate and the electric motor itself; this leaves Northern Comfort with a couple of options:
- Sea Water inlet/exit thruhulls
- Closed Loop Water
It seems to me that a more efficient way to use this heat is to try and heat up something useful like water for the shower. Although a finite amount of water, this seems to be a useful end result. I am currently evaluating a way to reconstruct the head to include a shower system and hot water would be nice. This might include an electric hot water tank with 2.5 to 4 gallon capacity. A navy shower is estimated to use 3 gallons over 10 minutes as opposed to the 60 gallons typically used in a house. It won’t be a rain head but it will be fresh water which will be a welcome relief to the salt water environment we may sail in.
Perhaps there should be a closed loop redirect flow valve that can alternatively use the water under the boat and/or the water in the boat. Because of the particles in the lake or sea water including dead biological matter, heat exchangers often build up debris and calcium buildups over time which can lead to plugging, flow restriction or outright failure. As an initial test I will be building a closed loop system to try and heat up water for the shower.
Stay tuned for further updates on this topic.
Recent Comments