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High Speed Counter and PWM Macros
Published in Murat Uzam, PIC16F1847 Microcontroller-Based Programmable Logic Controller, 2020
Table 2.11 summarizes operation of the H-bridge shown in Figure 2.25. When switches S1 and S4 are closed (while S2 and S3 are open) a positive voltage will be applied across the motor as shown in Figure 2.26(a). When switches S2 and S3 are closed (while S1 and S4 are open), this voltage is reversed, allowing reverse operation of the motor as shown in Figure 2.26(b). Switches S1 and S3 (or S2 and S4, respectively) should never be closed at the same time, as this would cause a short circuit on the input voltage source VMotor. The short circuit current on one side of the bridge could cause serious damage to the bridge itself or to the supply circuit. The H-bridge is generally used to reverse the polarity/direction of the motor, but can also be used to brake the motor.
Internet of Things-Based Speed and Direction Control of Four-Quadrant DC Motor
Published in Lavanya Sharma, Pradeep K Garg, From Visual Surveillance to Internet of Things, 2019
Bhupesh Kumar Singh, Vijay Kumar Tayal
In general, an H-bridge is a simple circuit consisting of four switching elements, i.e., transistors with the load at the center. The whole configuration depicts an H-like structure. The switching elements (Q1–Q4) are generally bipolar transistors, and diodes (D1–D4) are the Schottky type. The operation of an H-bridge is fairly simple. If Q1–Q4 are being turned on, the motor is going to move forward, and if Q2–Q3 are being turned on, the motor is going to reverse its direction. This is how the direction in the proposed model is controlled. However, to avoid a short circuit, care should be taken so that Q1–Q2 or Q3–Q4 are not closed simultaneously.
Mechatronics in Landmine Detection and Removal
Published in C.W. de Silva, Mechatronic Systems, 2007
T. Nanayakkara, L. Piyathilaka, A. Subasinghe
A circuit known as the H-bridge (named for its topological similarity to the letter H) is commonly used to drive motors. In the circuit shown in Figure 28.11, two of the four transistors are selectively enabled to control the current flow through a motor at a given time.
A three-phase transformer based T-type topology for DSTATCOM application
Published in International Journal of Electronics, 2021
Hari Priya Vemuganti, Dharmavarapu Sreenivasarao, Ganjikunta Siva Kumar
The Structural arrangement of five-level T-type configuration is shown in Figure 1(a). Depending on the way dc-link is connected, there are two possible configurations of three-phase T-type (full-bridge topology). The structural arrangement of these five-level T-type configurations is shown in Figure 1(a) and (b). This T-type topology is the congregation of bidirectional and uni-directional switches. Four unidirectional switches S1, S2, S3, and S4 are connected to form an H-bridge as shown in Figure 1(a) & 1(b). The dc supply is connected to H-bridge through the bidirectional switches. Equivalent of bidirectional switch (BS) is shown in Figure 1(c). Increase in the number of dc source and bi-directional switches increases the voltage levels, but the switches in H-bridge remain unaltered. However, the performance of both the configurations remains same, but the selection of the configuration should be wisely made depending on the application.
Designing MPC algorithms for velocity control of brushed DC motor and verification with SIL tests
Published in Automatika, 2023
BDC motor equations are based on armature current and angular velocity variables [17]. indicates armature resistance, is armature inductance, and are armature current and voltage, and is the back emf voltage. The back emf voltage depends on the motor velocity () and the back emf constant () [17]: The electric torque () generated by the motor depends on the armature current and torque constant () and is found in the following equation [17]. The velocity of the motor () depends on the resistance of the electrical torque against external and internal factors. In the velocity equation given below, represents external load, friction coefficient, and motor inertia [17]. The parameters of the motor are given in the Appendix. BDC motors are generally driven by H-Bridges. H-Bridge is an electronic circuit that allows voltage to be applied to a BDC motor in both directions. A primary H-Bridge circuit has four switching components (Transistor, Mosfet, etc.). Usually, there are 16 different switching possibilities if there are four switches. But due to the nature of the H-Bridge circuit, short circuits occur in 7 of these possibilities. For example, If S1 and S2 are open at the same time, it is seen that there will be a short circuit, and this situation will damage the circuit. This condition also occurs when S3 and S4 are open. In 5 switching combinations, the current will not flow from the circuit and turn OFF. For example, the state that all switches are OFF or only one of the switches is ON. Setting the S1 and S4 switches ON will cause the motor to turn in the forward direction while setting S2 and S3 ON will cause the motor to turn in the reverse direction. If only S1 and S3 are ON or only S2 and S4 are ON, the motor terminals will be short-circuited, causing a brake [18]. The H-Bridge circuit and BDC motor driving method are shown in Figure 1.
A New Reduced Number of Components-Based Voltage Boosting Multilevel Inverter
Published in Electric Power Components and Systems, 2023
Ashutosh Kumar Singh, Rajib Kumar Mandal, Ravi Anand
In recent times, many multilevel inverter (MLI) topologies and their applications have been deeply studied by researchers. These inverters are used in high voltage direct current (HVDC), electrical vehicles, and in renewable applications. Primarily, two-level and three-level inverters were presented and, due to their high voltage stresses on switches and high total harmonic distortion, they are not suitable for industrial applications. Nowadays, multilevel inverters are used, which have low total harmonic distortion, low stress on switches, and can produce any level of output voltage. Initially, the conventional MLI topologies were discussed, which are: Neutral Point Clamped (NPC) inverter, Flying Capacitor (FC) inverter, and Cascade H-Bridge (CHB) inverter. The NPC inverter consists of several switches, diodes, capacitors, and one power supply. As the number of levels increases, the NPC and FC inverters experience the voltage imbalance of capacitors. To resolve this issue, many modulation schemes and external circuits have been discussed in Refs. [1–3]. Additionally, NPC and FC require many capacitors and diodes, which makes them uneconomical [4]. Several circuits have been introduced in Refs. [5, 6], to improve the structure of conventional NPC and FC topologies. These structures cannot boost the input voltage. In high-voltage applications, cascade MLI is used, which is another kind of conventional inverter. This configuration includes cascading connections of H-bridges. An H-bridge consists of four unidirectional switches and one DC voltage source. It can be designed as asymmetrical or symmetrical. The magnitude of DC supplies is equal but uses many supplies and switches for producing higher levels in the case of a symmetric arrangement. Additionally, it uses a high number of switches in the current path, which yields higher conduction losses [7]. In the case of an asymmetrical CHB configuration, the magnitude of supply voltage is controlled by a mathematical algorithm. For both symmetric and asymmetric arrangements of CHB inverters, various topologies have been discussed in Refs. [8, 9] that need fewer components as contrasted to the traditional CHB configuration. The inverter discussed in Ref. [8] can be used to generate high-level voltage as the system can be cascaded, but the problem is that the switches have higher blocking voltage which increases the cost. To overcome this problem, the topology presented in Ref. [9] have a character of the previous one and also lowers the blocking voltage, but the problem is that both of these topologies do not have voltage-boosting capabilities. In Ref. [10], topology have the voltage-boosting capability but utilize 10 switches to generate 7-level. The structure discussed in Ref. [11] requires low-value voltage switches that make it appropriate for high-voltage applications. But, it requires many diodes, IGBTs, input sources, and capacitors.