Battery Charging Control Methods, Electric Vehicle Charging Methods, Battery Charging Apparatus and Rechargeable Battey Systems
The invention represents an algorithm to provide a form of regulation up and down services to the electric power grid using a plug-in electric hybrid vehicle (PHEV/EV) or electric vehicle (EV). The basis for this regulation will come from frequency measurements of the power grid. The actual charge rate of the PHEV/EV charger will be adjusted using this regulation signal and information about any charging constraints imposed upon the charger (such as a desired finish time).
CURRENT LIMITING CONTROL STRATEGY FOR SINGLE-LOOP DROOP-CONTROLLED-GRID-FORMING INVERTERS (iEdison No. 0685901-22-0109)
Existing studies of current limiting control for grid-forming inverters mostly focus on grid-forming inverters that use the multi-loop control structure. This paper describes a current limiting control for grid-forming inverters that use the single-loop control structure. The proposed current limiting control is implemented at the PWM control layer to guarantee the fast response. Once detecting the overcurrent caused by severe faults, the proposed control strategy immediately blocks relevant IGBTs using a hysteresis loop, ensuring the overcurrent can be limited within a few PWM cycles. After the fault is cleared, the inverter seamlessly transfers back to the droop control mode to maintain the stability. The current limiting control has been tested in a microgrid environment in the OPAL-RT platform. Study results show that the control strategy can effectively limit the overcurrent under both balanced and unbalanced faults, and the system transient stability can be maintained after the fault is cleared.
IN-SITU HEALTH MONITORING SYSTEM FOR REDOX FLOW BATTERIES (iEdison No. 0685901-22-0242)
We designed an acoustic monitoring system to detect hydrogen bubbles in the analyte solution of all-vanadium redox flow batteries (AVFBs). The system has a specially designed ultrasonic probing cell made of borosilicate glass that can be integrated into the flow system on the analyte side (Figure 1). The analyte solution firstly flows through the negative electrode, where the chemical reaction occurs and hydrogen bubbles are generated, and then flows into the ultrasonic probing cell. The ultrasonic transducer transmits signals into the probing cell and collects echoes that propagate through the electrolyte solution in the probing cell. Details about how the signals are transmitted and received are included in Appendix A. The echoes are collected by the ultrasonic receiver and sent to the computer for data analysis. The sound speed and the acoustic attenuation coefficient are calculated from these echoes, with the detailed methods given in Appendix B and C. Bubbles that flow through the acoustic path are reflected as abnormal values in the measurements of the sound speed and the attenuation coefficient. This method not only can detect bubbles in the analyte solution, but also can estimate the bubble flow speed. The monitoring system can continuously monitor bubble amounts in negative electrolytes without interrupting the battery operation, and thus provides a real-time noninvasive surveillance of the health status of flow battery systems. Figure 1. Schematic of the in-situ battery health monitoring system for hydrogen detection in an all-vanadium redox flow battery.
DIRECT SYNTHESIS OF NICKEL-RICH MONOCRYSTALLINE NMC FROM A TRANSITION METAL HYDROXIDE PRECURSOR AND A LITHIUM COMPOUND (iEdison No. 0685901-24-0165)
This invention is a follow-up work of our precious patents: US11862794B2 and US20220112094A1. Both titled 'Cost effective synthesis of oxide materials for lithium-ion batteries". Based on previous work, in this invention, one-step method to synthesize Ni-rich monocrystalline NMC is developed. The one-step method is: heat a solid hydroxide precursor comprising NixMnyMzCo1-x-y-z(OH)2 with Li2O to produce monocrystalline lithium nickel manganese cobalt oxide having a formula LiNiXMnyMzCo1-x-y-zO2.The time at high temperature annealing is reduced to 1 minute, making the synthesis of Ni-rich monocrystalline more cost effective.
Forward Looking Transactive Pricing Schemes for Use in a Market-Based Resource Allocation System
This is an extension of the Invention Disclosure for the Olympic Peninsula Demonstration Project. In this project, a rolling window of 24 hours was used to determine average price and standard deviations. The new method uses day ahead pricing to calculate similar values.
COORDINATION OF THERMOSTATICALLY CONTROLLED LOADS WITH UNKNOWN PARAMETERS
Apparatus and methods are disclosed for coordination of a population of Thermostatically Controlled Loads (TCLs) with unknown parameters to achieve group objectives including bidding and market clearing strategies designed to motivate self-interested users to realize efficient energy allocation subject to a peak power constraint. In one examples of the disclosed technology, a method of operating a load includes estimating a set of values for unmeasured parameters of the load's thermal environment based on output measurements of the thermal environment, determining an energy response based on the estimated set of values for the unmeasured parameters, and transmitting a bid for power for a finite time period based on the determined energy response to the coordinator. A clearing price is received from the coordinator responsive to the transmitted bid and power is sent to the load responsive to the received clearing price.
All-vanadium sulfate acid redox flow battery system
All-vanadium sulfate redox flow battery systems have a catholyte and an anolyte comprising an aqueous supporting solution including chloride ions and phosphate ions. The aqueous supporting solution stabilizes and increases the solubility of vanadium species in the electrolyte, allowing an increased vanadium concentration over a desired operating temperature range. According to one example, the chloride ions are provided by MgCl2, and the phosphate ions are provided by (NH4)2HPO4.
HYDROTHERMAL LIQUEFACTION SYSTEM WITH HEAT EXCHANGER NETWORK (iEdison No. 0685901-22-0139)
This invention segregates the heat integration in a hydrothermal liquefaction (HTL) process to reduce the design pressure and temperature requirements for piping, pumps, and heat exchanger equipment. Reducing the design conditions reduces the equipment cost and size and allows for multiple heat exchange technology options to be simultaneously utilized. The vapor pressure of water sets the system operating pressure. Water is very volatile, so the vapor pressure increases rapidly with operating temperature. Areas of the process that require high temperatures, such as the reactor, must be designed for a high operating pressure. However, areas of the process that do not operate at high temperatures can in principle be designed for lower operating pressure. The HTL process requires heating a slurry feed from ambient temperature to 600-700 degF. The large temperature change requires a significant investment in heat exchangers. Heat exchangers are responsible for > 70% of the capital cost of HTL. The design pressure of the heat exchangers has a major influence on the cost. The thickness of the heat exchanger shell is proportional to the design pressure. Therefore, reducing the design pressure by half will reduce the mass of metal required to make the shell by approximately half. In addition to heat exchangers being cheaper, lowering the design pressure allows additional styles of heat exchangers to be used. For example, spiral heat exchangers have many advantages over shell and tube heat exchangers for slurry service. However, the relatively low design pressure limitations of spiral heat exchangers have prevented their utilization for HTL. This invention separates the feed/product heat exchanger train into multiple sections operating at different pressures. Sections earlier in the heat exchanger train (operating at lower temperature) can operate at lower pressure, allowing them to be manufactured cheaper. Staging pumps are used to increase the pressure between the different heat exchanger sections. This invention allows for different heat exchanger technologies to be used between the multiple sections. One configuration proposed is to use a spiral heat exchanger design in the earlier, low pressure stages and shell and tube in the later, high pressure stages. This configuration could be advantaged because spiral heat exchangers perform very well in the HTL application due to their fouling resistance and reasonably good heat transfer with viscous fluids, but can be expensive to manufacture at high design pressures.