Electrical Load Emulator Using Segmented Control Modes
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing electrical load emulators for inverters are complex, costly, and heavy due to their complex control strategies and hardware topology, making them less portable and more expensive, especially when emulating dynamical load transients.
Innovation Solution
A low-cost electrical load emulator with a reduced number of components, utilizing a current sensor, coupling filter, and voltage sensing unit, along with a control unit that synchronizes or delays output voltage edges based on measured currents and voltages to emulate load transients, using a shared DC power source and programmable hardware like FPGA or microcontroller.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If complex control strategies and hardware topology are used in ELE, then emulation accuracy for dynamical load transients is improved, but device complexity, cost, and weight increase
Solution Approach 1:
The patent segments the control task into two distinct modes: voltage following mode for steady-state operation and current control mode for transient operation. This segmentation allows the system to use simple voltage following control during normal operation, reserving complex current control only when needed during transients, thereby reducing overall system complexity while maintaining emulation accuracy.
Solution Approach 2:
The patent implements dynamic switching between control modes based on operating conditions. The control unit automatically transitions between voltage following mode and current control mode depending on whether the system is in steady-state or experiencing transients. This dynamic adaptation allows the ELE to maintain high emulation accuracy only when necessary, reducing complexity during normal operation.
2Reliability
If complex control strategies and hardware topology are used in ELE, then emulation accuracy for dynamical load transients is improved, but cost increases
Solution Approach 1:
The patent segments the control task into two distinct modes: voltage follower mode for steady-state operation and current control mode for transient operation. This segmentation allows the system to use simple voltage following control during steady-state, reserving complex current control only when needed during transients, thereby reducing overall system complexity and cost while maintaining emulation accuracy.
Solution Approach 2:
The patent implements dynamic switching between control modes based on operating conditions. The control unit automatically transitions between voltage follower mode and current control mode depending on whether the system is in steady-state or experiencing transients. This dynamic adaptation allows the ELE to maintain high emulation accuracy only when necessary, reducing complexity and cost during normal operation.
3Reliability
If complex control strategies and hardware topology are used in ELE, then emulation accuracy for dynamical load transients is improved, but portability is reduced
Solution Approach 1:
The patent segments the control task into two distinct modes: voltage follower mode for steady-state operation and current control mode for transient operation. This segmentation allows the system to use simple voltage following control during steady-state, reserving complex current control only when needed during transients, thereby reducing overall system complexity and weight while maintaining emulation accuracy.
Solution Approach 2:
The patent implements dynamic switching between control modes based on operating conditions. The control unit automatically transitions between voltage follower mode and current control mode depending on whether the system is in steady-state or experiencing transients. This dynamic adaptation allows the ELE to maintain high emulation accuracy only when necessary, reducing complexity and weight during normal operation.
4Device complexity
If voltage follower control is used continuously, then hardware complexity is reduced, but emulation of load transients deteriorates
Solution Approach 1:
The patent implements dynamic switching between control modes based on operating conditions. The control unit automatically transitions between voltage follower mode and current control mode depending on whether the system is in steady-state or experiencing transients. This dynamic adaptation allows the ELE to maintain high emulation accuracy only when necessary, reducing complexity and cost during normal operation.
Solution Approach 2:
The patent prepares the control system to switch to current control mode in advance when transient conditions are detected. By monitoring operating conditions and pre-positioning the control mode, the system ensures that complex current control is already ready when transients occur, maintaining emulation accuracy without requiring continuous complex control.
Data Source
Figure 1
Figure 2~3
Figure 4
AI summary
The invention relates to an electrical load emulator (ELE) for an inverter under test (IUT), wherein an IUT output voltage VIUT at an IUT output terminal is configured to take a plurality of IUT voltage states, separated by rising and falling edges, and wherein an ELE output voltage at an ELE output terminal is configured to take a plurality of ELE voltage states, separated by rising and falling edges, and wherein to each IUT voltage state corresponds at least one ELE voltage state. The ELE comprises a current sensor configured to measure an IUT output current IIUT, a coupling filter for connecting the ELE to the IUT, a voltage sensing unit configured to measure the IUT output voltage VIUT, and a control unit configured to determine a reference current IREF corresponding to an emulated electrical load based on the measured IUT output voltage VIUT, and to compare the reference current IREF to the measured IUT output current IIUT.