This paper proposes a virtual position-offset injection based permanent magnet temperature estimation approach for permanent magnet synchronous machines(PMSMs). The concept of virtual position-offset injection is math...This paper proposes a virtual position-offset injection based permanent magnet temperature estimation approach for permanent magnet synchronous machines(PMSMs). The concept of virtual position-offset injection is mathematically transforming the machine model to a virtual frame with a position-offset. The virtual frame temperature estimation model is derived to calculate the permanent magnet temperature(PMT) directly from the measurements with computation efficiency. The estimation model involves a combined inductance term, which can simplify the establishment of saturation compensation model with less measurements. Moreover, resistance and inverter distorted terms are cancelled in the estimation model, which can improve the robustness to the winding temperature rise and inverter distortion. The proposed approach can achieve simplified computation in temperature estimation and reduced memory usage in saturation compensation. While existing model-based approaches could be affected by either the need of resistance and inverter information or complex saturation compensation. Experiments are conducted on the test machine to verify the proposed approach under various operating conditions.展开更多
Rechargeable Zinc(Zn)batteries exhibit great potentials as alternative energy storage devices due to their high safety,low cost,and environmental friendliness.However,the long-standing issues of low Coulombic efficien...Rechargeable Zinc(Zn)batteries exhibit great potentials as alternative energy storage devices due to their high safety,low cost,and environmental friendliness.However,the long-standing issues of low Coulombic efficiency(CE)and poor cycle stability of Zn anode,derived from dendrite,H_(2)evolution,and passivation are directly related to their thermodynamic instability in aqueous electrolyte,severely shorten the battery's cycle life.Recently reported electrolyte design strategies,which have made great progress to address Zn metal anode problems,are summarized into two categories,that is,aqueous electrolytes about cation-water interaction controlling and interface adjusting,and novel types of electrolytes towards less water,non-aqueous solvents,even no solvents.The final section shows the brief comparisons,including failure mechanisms of electrolyte exhaustion and short circuit for aqueous and nonaqueous electrolyte based full cells respectively,and possible perspectives for future research.展开更多
Reinforcing electronic and ionic conductivity is very important to realize the high-rate Li_(2)ZnTi_(3)O_(8)(LZTO)anode for Lithium-ion batteries(LIBs).Here,we reported a synthetic strategy toward in situ growth of ho...Reinforcing electronic and ionic conductivity is very important to realize the high-rate Li_(2)ZnTi_(3)O_(8)(LZTO)anode for Lithium-ion batteries(LIBs).Here,we reported a synthetic strategy toward in situ growth of homodispersed Li_(2)ZnTi_(3)O_(8)on ultralight 3D carbon aerogels(CAs)via facile heat treatment and activation process taking LiOH as activating agent.Such an optimized composite obtains a specific surface area of 154.427 m^(2) g^(-1) and a high pore volume.The strong interaction between the LZTO and N-doped CAs,a highly electrical conductivity and multidimensional ion transport channels of the hybrid result in a high capacity,outstanding high-rate performance and long cycle life.As a result,the NPC-LZTO electrode(NPC-LZTO-B)delivers a commendable reversible capacity at high-rate(e.g.162.4 mAh g^(-1) at 5 A g^(-1)(22 C)and 127.3 mAh g^(-1) at 10 A g^(-1))and durable long-term performance(capacity retention of 73% after 4500 cycles at 5 A g^(-1)).Moreover,the kinetic analysis confirms that the feature of pseudocapacitance boosts lithium-ion storage performance at high rate.Porous carbon aerogels frame constructed LZTO nanocomposite electrodes provide a facile way to design high durable LIBs anode.展开更多
基金supported in part by the National Natural Science Foundation of China under Grant 52105079 and 62103455。
文摘This paper proposes a virtual position-offset injection based permanent magnet temperature estimation approach for permanent magnet synchronous machines(PMSMs). The concept of virtual position-offset injection is mathematically transforming the machine model to a virtual frame with a position-offset. The virtual frame temperature estimation model is derived to calculate the permanent magnet temperature(PMT) directly from the measurements with computation efficiency. The estimation model involves a combined inductance term, which can simplify the establishment of saturation compensation model with less measurements. Moreover, resistance and inverter distorted terms are cancelled in the estimation model, which can improve the robustness to the winding temperature rise and inverter distortion. The proposed approach can achieve simplified computation in temperature estimation and reduced memory usage in saturation compensation. While existing model-based approaches could be affected by either the need of resistance and inverter information or complex saturation compensation. Experiments are conducted on the test machine to verify the proposed approach under various operating conditions.
基金financially supported by the National Natural Science Foundation of China(22179083)the Program of Shanghai Academic Research Leader(20XD1401900)the National Key R&D Program of China(2021YFB2400300)。
文摘Rechargeable Zinc(Zn)batteries exhibit great potentials as alternative energy storage devices due to their high safety,low cost,and environmental friendliness.However,the long-standing issues of low Coulombic efficiency(CE)and poor cycle stability of Zn anode,derived from dendrite,H_(2)evolution,and passivation are directly related to their thermodynamic instability in aqueous electrolyte,severely shorten the battery's cycle life.Recently reported electrolyte design strategies,which have made great progress to address Zn metal anode problems,are summarized into two categories,that is,aqueous electrolytes about cation-water interaction controlling and interface adjusting,and novel types of electrolytes towards less water,non-aqueous solvents,even no solvents.The final section shows the brief comparisons,including failure mechanisms of electrolyte exhaustion and short circuit for aqueous and nonaqueous electrolyte based full cells respectively,and possible perspectives for future research.
基金This work was financially supported by Science and Technology Commission of Shanghai Municipality(19DZ2271100).
文摘Reinforcing electronic and ionic conductivity is very important to realize the high-rate Li_(2)ZnTi_(3)O_(8)(LZTO)anode for Lithium-ion batteries(LIBs).Here,we reported a synthetic strategy toward in situ growth of homodispersed Li_(2)ZnTi_(3)O_(8)on ultralight 3D carbon aerogels(CAs)via facile heat treatment and activation process taking LiOH as activating agent.Such an optimized composite obtains a specific surface area of 154.427 m^(2) g^(-1) and a high pore volume.The strong interaction between the LZTO and N-doped CAs,a highly electrical conductivity and multidimensional ion transport channels of the hybrid result in a high capacity,outstanding high-rate performance and long cycle life.As a result,the NPC-LZTO electrode(NPC-LZTO-B)delivers a commendable reversible capacity at high-rate(e.g.162.4 mAh g^(-1) at 5 A g^(-1)(22 C)and 127.3 mAh g^(-1) at 10 A g^(-1))and durable long-term performance(capacity retention of 73% after 4500 cycles at 5 A g^(-1)).Moreover,the kinetic analysis confirms that the feature of pseudocapacitance boosts lithium-ion storage performance at high rate.Porous carbon aerogels frame constructed LZTO nanocomposite electrodes provide a facile way to design high durable LIBs anode.
