Heat Pump Startup Sequencing for Limited Generator Power
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Heat pump systems face difficulties in starting up from auxiliary power sources like generators due to high momentary currents required by inductive electrical components, exceeding the power capacity of the generator.
Innovation Solution
An HVAC system with a controller that selectively provides startup power to components, starting a first component with a lower power requirement before a second component, ensuring the total power requirement does not exceed the auxiliary power source's capacity, using a generator and battery for stable power supply.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Speed
If multiple components of the heat pump system are started simultaneously from an auxiliary power source, then the system can achieve faster startup, but the high momentary currents required by inductive electrical components will exceed the power capacity of the generator
Solution Approach 1:
The patent divides the startup process into sequential stages, starting with the compressor first, then followed by the condenser fan motor, and finally the evaporator fan motor. This segmentation of simultaneous startup into sequential startup reduces the peak power demand at any given moment while still achieving complete system startup.
Solution Approach 2:
The controller is configured to perform preliminary actions by starting the compressor first before activating other high-power components. This preliminary action ensures that the most critical component (compressor) is running before other components are started, reducing the risk of damage and optimizing system performance.
2Productivity
If the auxiliary power source is sized to meet the total startup power requirement, then all components can be started simultaneously, but the cost and complexity of the power source increases significantly
Solution Approach 1:
By segmenting the startup sequence and controlling components to start sequentially rather than simultaneously, the patent enables the use of a smaller, less expensive auxiliary power source that would be insufficient for simultaneous startup of all components.
Solution Approach 2:
The patent changes the temporal parameter of power delivery by spreading out the startup events over time rather than delivering all power simultaneously. This parameter change allows a smaller power source to meet the cumulative power requirements without being oversized.
3Reliability
If a larger generator is used to provide sufficient startup power, then all components can be started simultaneously, but the cost of the auxiliary power source increases
Solution Approach 1:
The sequential startup sequence segments the power demand into manageable portions, allowing a smaller generator to provide reliable startup power for each component in turn rather than requiring excessive capacity for simultaneous startup of all components.
Data Source
AI summary
Systems and methods are disclosed that may include providing an auxiliary power source in an HVAC system, establishing a stable, uninterrupted power source to at least one system controller, starting a first component of the HVAC system prior to starting a second component of the HVAC system. The total power requirement necessary to simultaneously start the first component and the second component may generally exceed the power output capacity of the auxiliary power source.