Torque converter operation

Thermal considerations are paramount for ATFs. A great deal of friction is produced, which generates heat and high-temperature spikes at the torque converter this will damage the fluid. ATF is designed to operate at temperatures around 95°C. At the torque converter, under extreme conditions, temperatures can reach 120°C. A transmission fluid should be designed to handle these temperature extremes. The transmission fluid will quickly break down above 120°C. Temperature spikes in the torque converter have been known to go above 120°C. 

M88 4-speed automatie transmission is equipped with the hydraulie torque converter and electric control system with locking. When keep the stable forward status, the hydraulic torque converter can be locked automatically when the engine operates in low speed, then reduce the unnecessary slide. 

TCU controls the hydraulic control system and the control is realized through the valve and pump assembly. The system includes 7 solenoid valves, in which 6 valves are used to control the line pressure, operate the shift valve and hydraulic torque converter lock clutch and switch on and off two regulating valves (Two regulating valves control the shift feel). The seventh solenoid valve is the pressure regulating solenoid valve (VPS) which controls the shift feel with other three regulating valves. Figure 3.1 is the typical TCU... 

For operation of specified vehicle refer to user operation manual. LU hydraulic torque converter lock clutch ... 

Most hydraulic machinery such as hydraulic turbines, pumps, fans, compressors, propellers, torque converters, fluid couplings, etc., operate at such high values of Reynolds Number that viscous forces are small compared with inertia forces. It is, therefore, eustomary and satisfactory to ignore Reynolds Number effects in the treatment of such problems. Hydraulie turbines are representative of this elass of equipment and will be briefly diseussed. 

It is important to note that the small-scale agitator operations may be described in terms of impeller diameter and agitator speed, while manufacturing process equipment is more conveniently specified by horsepower and fluid velocity. For most standard turbine configurations, power number correlations are available to convert impeller diameter and agitator speed into a horsepower value for given fluid properties. Most laboratory bench equipment is designed to provide a torque measurement that can be readily converted to horsepower directly from the conditions of the pilot batches. 

Despite the present-day dominance of ICE vehicles, recent environmental initiatives have revived interest in electric drives. The interest started with California, New York, and other states and regions with urban centres greatly affected by automotive emissions. Despite a recent survey s findings that expressed the view that there will be a sizable market in the next several years for EVs, the recent sales trend for EVs has not supported this without further qualification. It is now clear that a successful EV must match the ICE vehicle, not only in terms of performance (except some concession to range), but also at no additional cost [11]. This is not to say that there have not been some niche successes drivers and fleet owners of EVs are rediscovering some unexpected benefits of EVs with some sense of exploration collateral attributes such as lower maintenance, near-silent operation, and high torque starts are all benefits that have surprised many converts to the technology. One example in particular is instant cabin heat in winter, which is a current reality in pure EVs but still a number of years in the future for ICE-based vehicles. 

DC motor drives have always offered high torque at all speeds and exact control of motion speed. AC induction motors have reliably converted electricity into rotary power for many years, and recently adjustable-frequency controls add variable-speed capability. While AC motors were originally relegated to relatively simple tasks, such as varying the flow rates of fans or pumps, advances in both motor and control technologies have allowed their use in higher performance operations. They are reliable sources of fixed-speed and variable-speed rotating power. Electric drives with appropriate closed-loop control operate only when required. However, to avoid unsuccessful apphca-tions, it is important to properly match the load, motor, and controller. 

Principle Is the fundamental law that allows the development of a quantitative relation of the state variables. It governs behavior as the relationships among a set of state variables. For example, in Fig. 1, two possible principles are electromagnetism raling the operation of the electric motor and solid mechanics ruling the function of the crank mechanism. Behavior Represents the response of the structure when it receives stimuU. Since the structure is represented by state and structure variables, behaviors are quantified by the values of these variables. In the case presented in Fig. 1, the two behaviors are Generate torque and Convert torque into force. Function It is about the usefulness of a system. For example, in Fig. 1, one possible function of this system is to compress gas. 

In the case of constantly fluxed synchronous motors, the stator cmrent will follow the motor torque more closely. After adding excitation losses, the synchronous motor efficiency is still shghtly better than the induction motor. The drive inverter for a synchronous motor supplies the armature or torque producing current, compared to the induction motor apph-cation where the inverter must supply torque producing current and magnetising current In the synchronous motor application, the motor operates at unity power factor, which reduces current demand in the inverter section. As a result, there are fewer losses in the inverter and motor, and to a lesser extent fewer losses in the converter. 

Converter 2. The stator winding are connected in parallel so the motor current demanded at the starting process is around 570Arms (285 x 2) including the overload. The converter 2 is able to provide 600A at OHz and even more as the frequency increases so the full power (full speed-full torque) operation including the overload of 150% is ensured. This mode is selected when a failure occurs in the Converter 1. The CPU-1 controls the converter 2, the motor, its field excitation as well as the water cooling unit. 

The solution (based on two MV 100 frequency converters) allows a full redundancy operation with no hoist performance limitations. Thus, in case of a converter fails the drive system works in single mode (with one converter) but the full speed, full torque, and overload requirements are maintained, in such a way that service continuity is guaranteed without any performance limitation. 

The spindle viscometer (ASTMD2393) is one of the simplest instruments to operate. It measures torque required to rotate an immersed element (the spindle) in a fluid. The spindle is driven by a motor through a calibrated spring the deflection of the spring is measured and mathematically converted into a viscosity value in units of centipoise. By utilizing multiple rotational speeds and interchangeable spindles, a variety of viscosity ranges can be measured. 

This manipulated 4-20 mA current output is used to drive control status and deviation indicator for manual operation, or IP transducer of pneumatic valve for high torque operations or stepper motor drive for low torque operations. The current converter provides 1500V DC input to output isolation in interfacing the standard process signals. 

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