Abstract: When the ultra-high voltage direct current converter station is blocked,the cost of emergency load control of the receiving-end power system should be reduced as much as possible on the premise of security.Meanwhile,the receiving-end should also have sufficient reactive power support for the recovery of the inverter.An optimization method for emergency load control with economy and voltage stability coordinated is proposed.Firstly,the dynamic responses of the receiving-end system are analyzed when blocking accidents occur.The voltage vulnerability index can be used to identify the most vulnerable load nodes.The sum of squares of voltage dips of these nodes is taken as an index of voltage stability.Then,the cost of lost loads and penalties made are calculated.The total cost of emergency control is taken as the economy index.The piecewise linear penalty curves are approximated with polynomials to facilitate the optimization of sectional problems.Secondly,the emergency load control optimization problem is modeled under the constraints on frequency,voltage,maximum transmission power,etc.The objective is to minimize the weighted sum of economical and voltage stability indexes.The primal-dual interior point method is chosen to solve this problem for its fast speed.Finally,the algorithm is applied in the modified IEEE 10-generator39-bus system with two high voltage direct current transmission lines to verify its effectiveness.Simulation results show that the voltage stability is improved while the cost of control remains unchanged.And the coordinated optimal load control is beneficial to inverter recovery.