DSSim-XX communication library for MATLAB

Transcription

1 DSSim-XX communication library for MATLAB INTRODUCTION The DSSim-XX system is a graphic Distribution network Simulator for PC and Real Time (RT) systems [ 1-3 ]. This software is based in the EPRI s OpenDSS software to solve the electrical system and includes almost all the functionalities [4-7]. There are different versions of the DSSim-XX where the characters XX defines the functionality (it can be RT, PC, MT and OP). But all of them include a TCP communications server to allow the communication from an external client, this way the user can interact with this simulator no matter the programming language that he is used to use as shown in Figure 1. Figure 1. General functional schema of the DSSim-XX series

2 This manual presents the use of the MATLAB library developed to communicate the DSSim with and custom external application coded in this language. SET OF INSTRUCTIONS For each instruction, the library will deliver a 1 dimension array of strings with the answer for the query, so if the data that you are expecting is a number, you have to make the conversion of the data. For each instruction it is necessary to respect the use of capital and minuscule letters. Function Init This function is used to initialize the communication between the external client and the DSSim; it has to be used at the beginning of your application. DSSim_TCP('Init'); If the connection is successful, the algorithm returns an OK string. Function seconds This function will return the current number of seconds of the simulation. DSSim_TCP('seconds'); Function Close This function will close the communication link between the DSSim and the external application, it is necessary to include it in your when it finishes. DSSim_TCP('Close'); Function days This function will return the current number of days of the simulation (in seconds). DSSim_TCP('days');

3 Function Vpu This function will return the voltages p.u. of all the buses present in the circuit DSSim_TCP('Vpu'); Function V This function will return the voltages in magnitude of all the buses present in the circuit DSSim_TCP('V'); Function CapC This function will return the currents of all the capacitors present in the circuit DSSim_TCP('CapC'); Function CapV This function will return the voltages of all the capacitors present in the circuit DSSim_TCP('CapV');

4 Function CapL This function will return the losses of all the capacitors present in the circuit DSSim_TCP('CapL'); magnitude in kw and the magnitude in kvar, the magnitudes are total. Function CapP This function will return the powers of all the capacitors present in the circuit DSSim_TCP('CapP'); magnitude for each phase in kw and in kvar. Function XfrtC This function will return the currents of all the transformers present in the circuit DSSim_TCP('XfrtC'); Function XfrtV This function will return the voltages of all the transformers present in the circuit (terminal 1) DSSim_TCP('XfrtV');

5 Function XfrtL This function will return the losses of all the transformers present in the circuit DSSim_TCP('XfrtL'); magnitude in kw and the magnitude in kvar, the magnitudes are total. Function XfrtP This function will return the powers of all the transformers present in the circuit DSSim_TCP('XfrtP'); magnitude for each phase in kw and in kvar. Function LoadC This function will return the currents of all the Loads present in the circuit DSSim_TCP('LoadC'); Function LoadP This function will return the powers of all the Loads present in the circuit DSSim_TCP('LoadP'); magnitude for each phase in kw and in kvar.

6 Function LineC This function will return the currents of all the Lines present in the circuit DSSim_TCP('LineC'); Function LineP This function will return the powers of all the Lines present in the circuit DSSim_TCP('LineP'); magnitude for each phase in kw and in kvar. Function LineL This function will return the losses of all the Lines present in the circuit DSSim_TCP('LineL'); magnitude in kw and the magnitude in kvar, the magnitudes are total. Function SwitchC This function can be used to modify the current status of a specific switch, at difference of the others functions, this one requires additional arguments. DSSim_TCP('SwitchC','name of the switch','status'); The first argument is the name of the function and it is constant, the second argument is the name of the switch in the circuit (p. e. SW_1 ) and the third argument is the new status of the switch, if you want to open the switch it has to be a character 0, and for close the switch you will have to send a character 1. The next example it is to open the switch SW_1 in the circuit.

7 DSSim_TCP('SwitchC','SW_1','0'); If the operation is successful, the algorithm returns an OK string. Function Switch This function delivers the name and current status of all the switches present in the circuit. DSSim_TCP('Switch'); The information is delivered in pairs, where the first data is the current status and the second is the name of the switch. Function FixPower This function allows to the user to modify the current power of a load present in the circuit. It requires additional arguments DSSim_TCP('FixPower','Load name','multiplier'); The first argument is the name of the function and is a constant, the second argument is the name of the load to be modified (p.e. Load_1), and the last argument is to specify the multiplier to affect the nominal power consumed (or delivered) by the load. Use the character point (.) as decimal separator. The following example shows how to fix the power of the Load_1 to consume the half of his nominal power (programmed in DSSim). DSSim_TCP('FixPower','Load_1','0.5'); Function FixElement This function allows to the user to modify the current property of an element present in the circuit. It requires additional arguments DSSim_TCP('FixElement','full element name','property','value'); The first argument is the name of the function and is a constant, the second argument is the name of the element to be modified (the name must be a full name, this is, describing the type of element also p.e. Load.Load_1), the third argument is the property to modify (refer to the OpenDSS manual, p. e. QMult),and the last argument is to specify the value to affect the specified property. Use the character point (.) as decimal separator. The following example shows how to fix

8 the reactive power of the Load_1 to consume the half of his nominal reactive power (programmed in DSSim). DSSim_TCP('FixElement','Load.Load_1','QMult','0.5'); With this function the user can modify any property of any object in the system (refer to the OpenDSS manual). Function EnergyM This function delivers the name and current values of all the energy meters present in the circuit. DSSim_TCP('EnergyM'); The information is delivered as follows: first the name of the element for which the meter is connected, second the total active power measured (kwh), third the total active power measured (kvar) and finally the time (hours:minutes:seconds,miliseconds) of the sample. Function Inc_Mat This function delivers the branch-node incidence matrix of the compiled system. DSSim_TCP('Inc_Mat'); Remember that if you want to obtain the adjacency matrix, you must multiply the transpose of this incidence matrix by the non-transposed matrix. The first row of the matrix corresponds to the names of the columns of the matrix (names of the nodes), and the first column of the matrix is the name of the lines or elements that interconnect the nodes. Function EV&Storage_List This function delivers the server the list of the electric vehicles and storage elements within the current circuit.. DSSim_TCP('EV&Storage_List'); The sent message corresponds to a matrix of two columns with a number of rows equal to the number of elements (EV and storage elements) present within the circuit. The first column is the name of the element and the second one is the description of the element.

9 Function EV&Storage_Status This function delivers the electric vehicles and storage element status, with this instruction the remote user can read the charging status of the battery of each storage element within the circuit and his status (Charging, discharging or idling). DSSim_TCP('EV&Storage_Status'); The sent message corresponds to a matrix of Four columns with a number of rows equal to the number of elements (EV and storage elements) present within the circuit. The first column is the name of the element and the second one is the amount of energy stored (%), the third one is the amount of energy stored in kwh and the last one is the state of the charger (Charging, discharging or idling). Function SW_Currents. With this function, the remote client demands to the TCP server the currents of all switches placed in the circuit. Function SW_Losses. DSSim_TCP('SW_Currents'); With this function, the remote client demands to the TCP server the losses of all switches placed in the circuit. Function SW_Powers. DSSim_TCP('SW_Losses'); With this function, the remote client demands to the TCP server the powers of all switches placed in the circuit. Function Step_in. DSSim_TCP('SW_Powers'); With this function, the remote client forces the simulation to step in when it is in the Remote controlled simulation mode. It gives the control of the simulation progress to the user. Function Syntax: DSSim_TCP('Step_in'); The answer sent by the TCP server it is just a confirmation of the command, but if there is something wrong with the message received by the server, it will return an Error Message.

10 Function End_Sim. With this function, the remote client forces the simulation to terminate when it is in the Remote controlled simulation mode. DSSim_TCP('End_Sim'); The answer sent by the TCP server it is just a confirmation of the command, but if there is something wrong with the message received by the server, it will return an Error Message. Function Command. With this function, the remote client can interact directly with the OpenDSSEngine, it does not matter in which mode the simulation is running. DSSim_TCP('Command','select line '); The second argument is the OpenDSS command. In case that the command delivers a result, it will be contained in the first element (row 1, column 1) of the returned matrix. In the syntax example, the command select is applied to the line Function Monitors. With this function, the remote client demands to the TCP server the names of all harmonic or THD meters placed in the circuit. Function Mon_data. DSSim_TCP('Monitors'); With this function, the remote client request to the TCP server the data gathered by a specific harmonic or THD meter. DSSim_TCP('Mon_data','Mon_1234_m'); The second argument is the name of the meter to be consulted. In the syntax example, the meter that's going to be queried is the one named Mon_1234_m (to request the names of the placed monitors you can use the command Monitors.

11 REFERENCES [1] D. Montenegro, M. Hernandez, and G. A. Ramos, "Real time OpenDSS framework for distribution systems simulation and analysis," in Transmission and Distribution: Latin America Conference and Exposition (T&D-LA), 2012 Sixth IEEE/PES, 2012, pp [2] D. Montenegro, A. Ovalle, and G. A. Ramos, "Real Time distribution system simulator Based on OpenDSS," in Grid of the Future Symposium, Kansas City, MO, [3] D. Montenegro. (2013, 01, 07). DSSim-PC, Electrical Distribution Network simulator for PC. Available: [4] R. A. Walling, R. Saint, R. C. Dugan, J. Burke, and L. A. Kojovic, "Summary of Distributed Resources Impact on Power Delivery Systems," IEEE Transactions on Power Delivery, vol. 23, pp , [5] R. C. Dugan and T. E. McDermott, "An open source platform for collaborating on smart grid research," in 2011 IEEE Power and Energy Society General Meeting,, 2011, pp [6] R. C. Dugan, R. F. Arritt, T. E. McDermott, S. M. Brahma, and K. Schneider, "Distribution System Analysis to support the Smart Grid," in Power and Energy Society General Meeting, 2010 IEEE, 2010, pp [7] R. F. Arritt and R. C. Dugan, "Distribution System Analysis and the Future Smart Grid," IEEE Transactions on Industry Applications, vol. 47, pp , 2011.