Continuous-Time Approach to Discrete-Time PID Control for UPS Inverters - A Case Study

Błachuta, Marian; Rymarski, Zbigniew; Bieda, Robert; Bernacki, Krzysztof; Grygiel, Rafal

doi:10.1007/978-3-030-41964-6_15

Cited by 5 publications

(14 citation statements)

References 9 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Similar results of the discrete-time model for a VSI can be achieved using the c2d MATLAB function with the simplest ZOH discretization [30] or the discretization in the analytic way [8,9].…”

Section: Discrete-time Modeling Of the Voltage Source Invertermentioning

confidence: 73%

“…The second approach is based on solving the state-space equations (the discrete plant) and linearizing the control function [1,21,30]. The third approach is based on the continuous model of a VSI, adjusting the quasi-continuous-time counterpart of the discrete-time controller, and finally, using a discrete-time controller (the discretized controller) [8,9]. The first and third solutions are based on the averaged models.…”

Section: Discrete-time Modeling Of the Voltage Source Invertermentioning

confidence: 99%

“…The first presented example of an SISO control is a modern discretized PID controller (presented in detail in [8,9]), which uses the simplest SISO model from Figure 2 but includes an R LOAD . The quasi-continuous transfer function [8,9] of the plant K p (s) (including R LOAD ), considering a further ZOH discretization and one T s delay of the modulator, is shown in Equation (20),…”

Section: Siso Control Of a Vsimentioning

confidence: 99%

“…These coefficients were analyzed based on the root locus [8]. In Reference [9], these coefficients were slightly adjusted: b 0 = 18.381, b 1 = 34.179, b 2 = 16.423.…”

Section: Siso Control Of a Vsimentioning

confidence: 99%

“…The main advantage of an SISO solution is its simplicity and low cost because only one trace measuring output voltage with galvanic isolation is required. There have been some improvements to SISO using double control loops-a fast inner loop, e.g., a proportional-integral-derivative controller PID [8,9] or the coefficient diagram method (CDM) [10][11][12], and an outer loop that is only used to damp harmonic distortions, e.g., a repetitive controller (RPC) [13][14][15][16][17][18]. A repetitive controller is a discrete-time harmonic generator [14] that is plugged into the outer feedback loop, which works perfectly in the steady state The assignment of a linear or nonlinear plant model is the basic problem in control loop design.…”

Section: Introductionmentioning

confidence: 99%

See 4 more Smart Citations

Different Features of Control Systems for Single-Phase Voltage Source Inverters

Rymarski

Bernacki

2020

Energies

Self Cite

View full text Add to dashboard Cite

The aim of this paper is to determine which type of control loop is better for each particular type of standard voltage source inverter (VSI) load (static, dynamic, nonlinear rectifier resistive-capacitive RC load). A comparison of three different types of controllers for single-phase VSIs is presented. The first two are of the single input single output (SISO)/proportional-integral-derivative controller (PID) and coefficient diagram method (CDM) types, and the third is of the multi-input single output (MISO)/passivity-based control (PBC) type. The selections of the gains for SISO and MISO controllers are presented, including the problem in the choice of PBC controller gains caused by the imperfection of the pulse width modulation (PWM) modulator. For a standard nonlinear rectifier RC load, the new control quality factor (CQF) is defined to distinguish the properties of the controllers. The results show the superiority of the MISO-PBC controller for the RC load; however, for a linear dynamic load, the MISO-PBC performed worse than the SISO-PID or CDM. Therefore, the choice between either a simple and inexpensive SISO with one measurement trace or an expensive MISO with three measurement traces depends on the purpose of the VSI. The initial simulations and measurements of the experimental models are presented and discussed.

show abstract

Section: Discrete-time Modeling Of the Voltage Source Invertermentioning

confidence: 73%

Section: Discrete-time Modeling Of the Voltage Source Invertermentioning

confidence: 99%

Section: Siso Control Of a Vsimentioning

confidence: 99%

“…These coefficients were analyzed based on the root locus [8]. In Reference [9], these coefficients were slightly adjusted: b 0 = 18.381, b 1 = 34.179, b 2 = 16.423.…”

Section: Siso Control Of a Vsimentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 3 more Smart Citations

Different Features of Control Systems for Single-Phase Voltage Source Inverters

Rymarski

Bernacki

2020

Energies

Self Cite

View full text Add to dashboard Cite

show abstract

Improving Low-Frequency Digital Control in the Voltage Source Inverter for the UPS System

Rymarski

2024

Electronics

Self Cite

View full text Add to dashboard Cite

Today voltage source inverters (VSIs) operate with high switching frequencies (let us assume higher than 50 kHz) owing to the fast Si (Silicon) or SiC (Silicon Carbide) switching transistors. However, there are some applications, e.g., with slower switches (e.g., IGBT—Isolated Gate Bipolar Transistor) or when lower dynamic power losses are required when the switching frequency is low (let us assume about 10 kHz). The resonant frequency of the output filter is usually below 1 kHz. The measurements of Bode plots of the measurement traces of various microprocessor-controlled VSIs show that in this frequency range, the characteristics of these channels can be simply approximated through two or three switching periods delay. For the high switching frequency, it is not noticeable, but for the low frequency it can cause some oscillations in the output voltage. One of the solutions can be to use the predictor of the measured state variables based on the full-state Luenberger observer or the linear Kalman filter. Both solutions will be simulated in MATLAB/Simulink and the chosen one will be tested in the experimental VSI. The research aims to omit delays in the measurement channels for the low switching frequency by using the predictions for the measured state variables and finally increasing the gains of the controller to decrease the output voltage distortions.

show abstract

Sampling Rate and Performance of DC/AC Inverters with Digital PID Control—A Case Study

2021

View full text Add to dashboard Cite

The huge influence of the sampling rate on the performance of the digital PID control of a voltage source inverter (VSI) is revealed. It is shown that an appropriately chosen continuous-time model of a digital controller with the PWM power converter behaves like the actual discrete-time system, which allows for a simple controller analysis and design. The variable structure nature of the inverter with both the RC rectifier and an abruptly changing resistive load with two modes of operation within the sampling period is directly taken into account. Two simulation models, a discrete-time PWM and a continuous-time, of an inverter are presented, which are used to tune the PID controller and to evaluate the control performance. The behavior of the system in both modes is explained on the basis of the root loci and frequency characteristics. The results obtained for three sampling rates: 12.8, 25.6, and 51.2 kHz, are presented and compared with an actual VSI experiment. A comparison with other results obtained for this VSI shows that properly tuned PID control outperforms the more sophisticated solutions based on the coefficient diagram method (CDM) and the passivity based control (PBC).

show abstract

Continuous-Time Approach to Discrete-Time PID Control for UPS Inverters - A Case Study

Cited by 5 publications

References 9 publications

Different Features of Control Systems for Single-Phase Voltage Source Inverters

Different Features of Control Systems for Single-Phase Voltage Source Inverters

Improving Low-Frequency Digital Control in the Voltage Source Inverter for the UPS System

Sampling Rate and Performance of DC/AC Inverters with Digital PID Control—A Case Study

Contact Info

Product

Resources

About